Evaporation Control 

Research, 1959-60

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1692

Prepared in cooperation with the Texas 

Department of Agriculture, and in 

collaboration with Southwest Research 

Institute and Southwest Agricultural 

Institute
Evaporation Control 

Research, 1959-60

By GORDON E. KOBERG, ROBERT R. CRUSE, and CHARLES L. SHREWSBURY 

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1692

Prepared in cooperation with the Texas 

Department of Agriculture, and in 

collaboration with Southwest Research 

Institute and Southwest Agricultural 

Institute

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1963
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEWART L. UDALL, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

The U.S. Geological Survey Library has cataloged this publication as follows:

U.S. Geological Survey.

Evaporation control research, 1955/58- 

Washington, U.S. Govt. Print. Off., 1960-

v. illus., diagrs., tables. 24 cm. (Its Water-supply paper 1480,1692 

Prepared in cooperation with the Southwest Research Institute and 

other agencies.

1. Evaporation control. I. Title. (Series)

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington 25, D.C.
CONTENTS

Page

Abstract_______________________________________________________ 1

Introduction._____________________________________________________ 2

Theoretical considerations __________________________________________ 3

Film resistance to evaporation.-________________________________ 3

Theory of spreading___________________________________________ 5

Laboratory studies______________________________________________ 5

Experimental _________________________________________________ 6

Laboratory conclusions.._______________________________________ 13

Field studies._____________________________________________________ 14

Description of test sites.-____________-__-___-_-_-___--_-_--_--- 14

Evaluation method ____________________________________________ 15

Field tests__________ ____ ____ _ ____ __ _________ 17

Conclusions on field tests.______________________________________ 37

Suggesti6ns for future work_________________________________________ 39

Laboratory studies___-_-_____________-___--_-_-__-_-___----- 39

Field studies._________________________________________________ 40

References cited.__________________________________________________ 42

Index.___________________________________________________________ 55

ILLUSTRATIONS

FIGURE 1. The orientation of alkanols on the surface of the water.___-_ 4

2. A comparison of oil-in-water and water-in-oil dispersions

and the orientation of the emulsifying agent molecules.-.-- 7

3. A comparison of photomicrographs of O/W and W/O type

dispersions______________________-__--_------------- 11

4. A schematic diagram for the process of coacervation________ 13

5. Instrumentation raft showing anemometer and shelter fcr

thermograph_ ______________--______-------__------- 16

6. Relation between reservoir change in stage (AH) and th^

product uAe for Pinta Valle stock tank__________________ 17

7. Location of eight dispensers at Briones stock tank_____-__-_ 18

8. Anaerosol-type fielddispenser-__-____-___-_-_------------ 19

9. Diagram of electrical circuit used to control the aerosol-type

dispenser at Briones stock tank.___________-_-_____----- 19

10. Agravity-type dispenser-__---___----____--------_----_-- 21

11. Diagram of electrical circuit used to control the gravity-typ°.

dispenser at Briones stock tank_______________---------- 21

12. Drip dispenser at Zimmerman stock tank.___-___-__-__---_ 23 

13. Location of drip dispensers around Zimmerman stock tank- _ _ _ 24

in
IV CONTENTS

Page 

FIGURE 14. Sketch of wind-controlled dispenser.______________________ 25

15. Location of wind-controlled dispensers of Pinta Valle stock

tank______________________________________ 26

16. Floating barrier._____________________________________ 28

17. Wind-controlled dispensers at Carlos stock tank_ ___________ 29

18. Location of seven dispensers at Essar Ranch Lake__________ 34

19. A band of film across lake_----_--------------__-_------- 35

TABLES

TABLE 1. Emulsifiers available for evaluation with water evaporation

retardants ________________-_____--__------___-_----_- 45

2. Water-in-oil emulsions using 250 grams of dodecanol as the

oil___________________________-__________ 46

3. Oil-in-water dispersions of alkanols______________________ 46

4. Water-in-oil dispersions of hexadecanol and octadecanol-___ 52

5. Dispersions containing 11 to 20 percent octadecanol (Lorol 

28) based on water, and using glyceryl monostearate 

(self-emulsifying) as the dispersing agent______________ 53

6. Dispersions of octadecanol containing varying amounts of 

glyceryl monostearate (self-emulsifying) as the dispersing 

agent._______________________ ________---___-----__- 53
EVAPORATION CONTROL RESEARCH, 1959-60

By GORDON E. KOBERG/ ROBERT R. CRUSE,* and CHARLES L.

SHREWSBURY 3

ABSTRACT

Two hundred and forty-five dispersions of long-chain alkanols were formulated 

by using various emulsifiers and alkanols. The dispensing and spreading ability 

of each of these formulations was tested. The most promising emulsifier that 

could be used with any of the alkanols was glyceryl monostearate (self-emulsifying). However, the concentration of the alkanol in the dispersion fora: varied 

somewhat with the length of the carbon chain. A maximum concentration of 16 

percent was obtained using the longer chain alkanols in the dispersion form without losing any of the properties of a fluid.

Nine field tests were undertaken on small stock tanks. The retardant materials used in these tests were dodecanol, hexadecanol, and octadecanol. These 

materials were applied in either liquid or dispersion form. Four types of dispensing equipment were tested. The first type used a pressure system which 

sprayed a liquid onto the surface of the water. An anemometer and w'nd-controlled vane, operated by an electrical system, determined the length rnd frequency of application. The second type was similar to the first except that 

gravity was utilized to force the liquid onto the surface. The third type used a 

drip system with rates of about 10 drops per minute. The fourth type used a 

gravity feed and a wind-controlled valve which allowed the dispersion material 

to flow onto the surface of the water when the wind was in the proper direction.

In the field tests, the best reduction in evaporation was obtained using octadecanol in dispersion form and dispensed with the wind-controlled valve and 

gravity feed system. The maximum reduction in evaporation for a 2-week 

period was 27 percent. However, the economics of suppressing evaporation 

from stock tanks is questionable because of the short travel time across the tank 

by the film.

There are still many problems unsolved. Some of these can be resolved in 

the laboratory whereas others can be resolved only in the field. Some of the 

more serious problems are the effect of impurities in the alkanols; the rate of 

cooling of the alkanol from a liquid to a solid state; the effect of the film on the 

exchange of water molecules between the air and water; whether the film remains effective in suppressing evaporation for any rate of movement downwind; 

and the possible use of dodecanol and eicosanol as suppressants.

1 U.S. Geol. Survey.

2 Southwest Research Institute. 

8 Southwest Agricultural Institute.
2 EVAPORATION CONTROL RESEARCH, 1959-60

INTRODUCTION

The purpose of this investigation was to develop a practical, safe, 

and effective method of treating the surface of a water reservoir with 

a monomolecular chemical film to reduce loss of water by evaporation.

These objectives are the same as those of an earlier investigation 

reported by Cruse and Harbeck (1960).

This report describes the laboratory and field investigations during 

the period 1959-60. The emphasis in the laboratory investigations 

was to formulate and test various dispersions of alkanol for their 

spreading ability and ease of dispensing. The field investigations 

were made to evaluate the success of the various formulations in reducing evaporation in which the formulations were dispensed from 

several types of dispersions. These investigations were made in cooperation with the Texas Department of Agriculture, and in collaboration with the Southwest Research Institute and Southwest Agricultural Institute, both at San Antonio, Tex.

The loss of water by evaporation from lakes and reservoirs is a serious problem in areas where the limited water supply cannot meet the 

demands of the users. A possible method of increasing this supply is 

by conserving the water that would normally be lost by evaporation. 

Rideal (1925) demonstrated in the laboratory that water surfaces 

covered with monolayers of fatty acid had slower evaporation rates 

than those without the fatty acid. Since then, other workers have 

confirmed his work, but have indicated that greater reductions can be 

obtained from monolayers of the longer chain alkanols.

The first application of monolayers to open surfaces of water was 

made in the early 1940's but the results were inconclusive. In 1952, 

Mansfield (1955) began field testing monolayers in Australia and reported that evaporation rates were reduced by as much as 30 percent. 

Thus encouraged, investigators in this country began field studies in 

1955. Results to date have not been very encouraging because reliable 

methods for applying and maintaining a monolayer on r,n open surface of water have not been developed. The greatest difficulty is that 

the problems in field application are not always clearly understood. 

Most investigators therefore have used trial and error methods in an 

attempt to develop satisfactory techniques.

Some investigators have considered the possible use of monolayers 

to reduce losses from plant transpiration and evaporation from soils. 

Preliminary reports have indicated that this may be feasible. Such 

studies, however, are not within the scope of this report which deals 

only with the application of monolayers to open surfaces of water.
EVAPORATION CONTROL RESEARCH, 1959-60 3 

THEORETICAL. CONSIDERATIONS 

FILM RESISTANCE TO EVAPORATION

It has been demonstrated through laboratory experiments that when 

a monomolecular film is formed on the surface of the water from 

alkanols, evaporation is thereby reduced. However, the conditions 

under which these experiments are conducted never simulate field conditions completely. Even if actual field conditions were simulated, 

the results may be questionable as each experiment would be very 

difficult to reproduce because of the many meteorological variables.

According to Kosano and La Mer (1956), three sets of conditions 

have been employed in the laboratory to measure the rate of evaporation of water through films. The conditions are: (1) A current of 

air is passed over the surface; (2) the air above the surface is free of 

convection currents; (3) a partial vacuum is created above the surface. Condition 1 will generally approximate field conditions but 

does not take into account the continual movement of the film downwind. Condition 2 will only approximate field conditions for special 

periods when the atmosphere is stable and wind speeds are very low. 

Condition 3 will never exist. Therefore, the laboratory results of 

determining the effectiveness of the film in suppressing evaporation 

are not applicable for general field conditions, but are applicable only 

for specific conditions. However, these results serve a useful purpose 

when comparing one type of film with another. Also, laboratory tests 

define the effectiveness of the film in relation to temperature and film 

pressure.

The laboratory results from condition 3, according to Harkins 

(1952), should give the best results for retarding evaporation. He 

reasoned that when air is present over the surface nearly every water 

molecule which succeeds in moving out of the surface moves Hck in 

again. But this is not true when the evaporation into a vacuum takes 

place a vacuum eliminates or minimizes the effect of the filrr in retarding the return movement of molecules from the air to the water.

The effect of the film in retarding the movement of water molecules 

from the air through the film lias never been considered. It is possible 

that the film may have more retarding effect to the movement of molecules from the air to the water than from the reverse direction Hcause 

of the orientation of the alkanol molecules. The alkanol molecules 

are oriented, according to the theory of spreading (Harkins, 1952), 

with the polar end toward the water and the nonpolar end toward the 

air as shown in figure 1. The nonpolar end would repel water molecules from the air while the polar end would attract water molecules. 

For this reason the resistance of the film should be more effective to
EVAPORATION CONTROL RESEARCH, 1959-60

Air

Water

FIGURE 1. The orientation of 

alkanols on the surface of the 

water with the polar end in the 

water and the nonpolar end extending into the air.

the movement of water molecules from the air to the water, especially 

at low film compression where the resistance of the film is not very 

effective in retarding the movement of molecules from the water to 

the air. Laboratory experiments are needed to determine whether 

the film retards the movement of water molecules from the air to the 

water under different conditions of humidity and surface compression.

If this theory is correct, the effect of the film in the field under low 

film pressures and high humidities would be to increase the evaporation rate. Some field tests have indicated this to be true, but the 

data were not conclusive enough to confirm the theory. Of course, 

under high film pressures the film would be effective in retarding 

evaporation under most humidity conditions.

McArthur and Durham (1957) in their laboratory worh have indicated that the most effective film should be at least 5 molecules thick. 

The measurement of the thickness is based on the amount of dosage 

applied to the surface of the water. As the measurement of thickness 

is based on theoretical considerations and is not substantiated by direct 

measurements, the work may be somewhat questionable.

In the field there is no way, as yet, of determining the thickness of 

the film. It is believed by some investigators that the film thickness 

is 1 molecule thick while others believe it to be 1 or severrl molecules 

thick. Photographs of the film in the field have indicated that the reflection of light from the film for some areas seems to be different 

from others. This change in light reflection could be caused by the
LABORATORY STUDIES 5

variation in thickness of the film. However, it is also possible that 

surface pressure may have some effect on the reflected light.

THEORY OE SPREADING

According to Harkins (1952), films may form upon the surface 

of a liquid or a solid either by condensation from a vapor (adsorption) or by the liquid of a solid body, which floats upon ov is in 

contact with the surface. Film formation, then, will occur only at 

the surface of the water and around the perimeter of the solid material forming the film. For rapid film formation, the alkano.1 when 

placed on the surface of the water should remain and spread out 

over the water surface, creating a large perimeter.

In order to maintain film coverage in the field, where the film material is applied at a point source, film formation should be as rr.pid as 

possible in order to replenish the loss of film by the wind. According 

to McArthur and Durham (1957), a moderate wind moves tl °, film 

in a downward direction at a rate of 14 fpm (feet per minute). At 

this rate 14 square feet of film would be removed from the water surface for every lineal foot along the upwind shoreline. Therefore, 

when a film-forming material is placed on the surface of the water at 

a point source it must remain and break up rapidly to form many small 

air-water perimeters for film generation; consequently, the laboratory 

work in this investigation has been devoted to finding the smallest 

particle size of the solid material that can be preserved and easily 

dispensed from an unattended point source.

LABORATORY STUDIES

The field application, there are three possible methods of ap flying 

the alkanols in a small particle size: (1) Use of a dry powder, (2) use 

of the powder dispersed in a liquid and applied as a fluid, and (3) use 

of a solvent that will dissolve the alkanol. Since methods 1 and 3 

were being tried by other investigators, method 2 was selected for 

testing. Furthermore, it was considered to be the most economical 

method of application.

If an alkanol is ground to a fine powder and mixed with water, the 

powder will remain dispersed as long as mixing occurs; however, 

the powder and water will begin to separate when mixing stops. This 

is not desirable for field use when the force of gravity is used to move 

the liquid. In this case, continual mixing would be required to keep 

the powder dispersed so that a uniform mixture could be dispensed 

when needed.
6 EVAPORATION CONTROL RESEARCH, 1959-60

The use of dispersions or emulsions seem to be the most, promising 

to overcome the problem of separation, and the emphasis has been on 

finding a dispersion that will not separate, that will flow as a liquid 

and that will break up immediately when placed 011 the water surface.

Two general types of dispersions are described in the literature 

(Becher, 1955, 1957). These are oil-in-water (O/W) and water-inoil (W/O). Both types of dispersion were studied in th°, course of 

this work. As an evaporation retardant, the water-in-oil dispersions 

should be superior to the oil-in-water dispersions. Because the formation of a monomolecular evaporation-retardant film takes place only 

at the surface of the reservoir, the water-iii-oil dispersion, having the 

oil as the continuous, or external, phase would expose the evaporation 

retardant (the oil phase in this case) to the surface of the reservoir 

immediately. When an oil-in-water dispersion is used, the water, 

which is the continuous phase, must be dispersed before the surface 

phenomenon of spreadiiig-the-oil phase can occur. This is illustrated 

in figure 2.

A secondary, but nonetheless important criterion in selecting the 

dispersing agents for any recommended formulation, is the toxicity 

of the dispersing agent itself. The U.S. Public Health Service 

(Cincinnati, Ohio) has granted unqualified clearance to the use of 

1-hexadecaiiol and 1-octadecanol as evaporation retardants. No such 

clearance has been granted any of the dispersing agents when formulated with the evaporation retardants. Therefore, although all types 

of dispersing agents were considered, attempts were mad^ to choose 

a dispersing agent for the final formulation that would not be considered toxic by either the U.S. Public Health Service or the U.S. 

Food and Drug Administration on the basis of prior food use or other 

criteria. The dispersing agents that were considered and are available for experimentation are listed in table 1.

EXPERIMENTAL

The first of several dispersion and emulsion formulatiors prepared 

in the laboratory were the W/O type. These dispersionr were prepared by heating 250 grams of dodecanol (Lorol 7) to about 80°C 

in a 2-liter beaker. In a separate beaker, 250 ml of water was heated 

to 80°C. The emulsifying agent was added to the oil phase, or in 

this case to the dodecanol. The water was added to the oil while still 

hot, and stirred vigorously until cool. W/O dispersion^ prepared 

using dodecanol are summarized in table 2. All these dispersions 

separated or formed pastes which are not desirable for field use.
LABORATORY STUDIES

Water phase

Emulsifying agent

OIL-IN-WATER

Oil phase

Emulsifying agent

WATER-IN-OIL

FIGURE 2. A comparison of the oil-in-water and the waterin-oil dispersions and the orientation of the emulsifying 

agent molecules.
8 EVAPORATION CONTROL RESEARCH, 1959-60

In view of the high viscosity of the dispersions produced by the 

procedure using dodecanol, emphasis was placed for a time on the 

preparation of O/W type dispersions. These were prepared by 

heating the water (500 ml to 1 liter) to 80°C, adding the emulsifying 

agent, and then adding the molten alkanol. Vigorous stirring was 

maintained until the mixture was cold. An alternative procedure, 

with which it was somewhat easier to work, involved Hating the 

water and the alkanol together until the alkanol had melted. The 

mixture was placed under a high-speed stirrer and the emulsifying 

agent was added. Stirring was continued until the mixture was cold. 

The procedures proved to be interchangeable. Data on preparation 

of O/W type dispersions are summarized in table 3, with remarks 

concerning separation and whether the dispersions were liquid, paste, 

or gelatinous. The W/O type dispersions in table 3 were ir ostly pasty 

or gelatinous. When the paste or gelatinous material ie placed on 

the surface of the water, it does not break up rapidly; consequently, 

water-in-oil dispersions were again investigated. Becher (1955) indicates that W/O type dispersions are best prepared using greater than 

50 percent oil in their formulation. A previous experiment in this 

study, using the self-emulsifying glyceryl monostearate as the dispersing agent and equal amounts of dodecanol and water, yielded a W/O 

type dispersion with a pasty consistency similar to that of mayonnaise. 

Becher (1957) also indicated, contrary to the above statement, that 

under some circumstances it was possible to prepare W/O type dispersions containing greater than 50 percent water by giving careful 

attention to the following details: (1) Adding the water to the oil 

phase with agitation, and (2) making sure that the sides of the reaction vessel were coated with the continuous phase (in this case the oil 

phase would be alcohol). It seemed likely, then, that W/O type 

dispersions would be possible if hot water were added to an agitated 

oil and dispersant mixture with the oil phase being on the rides of the 

reaction vessel as the water is being added. The procedure involved 

melting the desired amount of alcohol together with the dispersing 

agent in the amount of 10 percent by weight of the alcohol. The 

mixture of the two was heated above the melting point of the alcohol 

and stirred vigorously. Next, the desired amount of hot wp,ter (about 

70° to 80°C) was added, and stirring was continued until the mixture 

cooled.

Data on W/O type dispersions prepared by this procedure are presented in table 4. Because of the pasty appearance of the first four 

dispersions (255-258) as well as the emulsions of dodecanol previously 

prepared, a series of dispersions using hexadecanol with glyceryl monostearate (self-emulsifying) as the dispersing agent was prepared,
LABORATORY STUDIES 9

and larger amounts of water were used in order to ascertain whether 

the use of more water would cause an inversion to an O/W type dispersion. Inversion did not seem to occur. Dispersions 261 through 

264 were those prepared in this particular series. Dispersion 264 

proved to be very promising, from the standpoint of breakup, spreading rate, and viscosity characteristics. Both the quantities of materials and the order and method of mixing employed in this improved 

procedure were used in subsequent preparations of W/O type dispersions. By this procedure, W/O type dispersions containing concentrations of up to 16 percent by weight of solid octadecanol, as 

shown in table 5, can be obtained without sacrificing the viscosity of 

the liquid dispersion. With O/W type dispersions, 2.5 percent by 

weight of octadecanol appears to be a desirable average, with 4 percent a maximum in hot weather. Greater than 4 percent hexadecaiiol 

or octadecanol renders the dispersion too viscous for easy handling.

To determine the percentages of hexadecanol that can be used in 

W/O type dispersions, a series of three dispersions was prepared. 

Each of these utilized 1 liter of water; 100, 150, and 170 grams of 

hexadecanol (Lorol 24) respectively; and 10 percent by weight of 

glyceryl monostearate (self-emulsifying), based on the amount of 

hexadecanol. All three dispersions proved undesirably thick for field 

use. To get some idea of the numerical value of the viscosity, the dispersions were placed at room temperature (about 82° F) on a Fann 

V-G viscosimeter. The 10 and 15 percent hexadecanol dispersions 

prepared as described above were used. Results were as f ollov's: 10- 

percent dispersion, viscosity 110 centipoises; and 15-percent dispersion, viscosity 93.5 centipoises.

The dispersions are obviously non-Newtonian fluids, and hence the 

value of the viscosity in centipoises may not be significant in terms of 

the ability of the dispersion to flow through the dispensers.

The use of W/O type dispersions of hexadecanol in the field is 

limited to 8-percent concentrations of hexadecanol as compared with 

16-percent concentrations of octadecanol. The reason for this is unknown. The only apparent difference between the two alkanols is 

that octadecanol has a longer chain than hexadecanol, but this does 

not seem to be a likely reason for using different amounts of concentrates. In view of this uncertainty, a short set of experimerts were 

conducted to ascertain whether an eicosanol or a docosanol, both of 

which have longer carbon chains than octadecanol, would be unable in 

a dispersion. Previous work had indicated that eicosanol and docosanol would not spread adequately. However, it was felt that a W/Odispersion might add enough spreading ability to the material, owing 

to the surfactant (dispersant) present, to cause a change in the per-
10 EVAPORATION CONTROL RESEARCH, 1959-60

f ormance of these alkanols and thus produce a thicker monomolecular 

layer. Using the same mixing procedure that previously used for the 

W/O type dispersions, the following dispersions were prepared with 

these materials:

Alkanol A

(Adol 60 80 percent 1-docosanol, 12 percent

1-eicosanol, and 8 percent 1-octadecanol) 97 grams 

Glyceryl monostearate 9.7 grams 

Water 970 grams 

Alkanol B

(Adol 67 25 percent 1-docosanol, 30 percent 

1-eicosanol, 30 percent 1-octadecanol, 15 percent 

1-hexadecanol) 93 grams 

Glyceryl monostearate 9.3 grams 

Water 930 grams

Both the A and the B dispersions were stable and quite fluid. A 

field test of the spreading rate indicated that both dispersions were 

comparable to that of octadecanol.

In making up these dispersions for test purposes, the questions arose 

as to the amount of dispersing agent needed to disperse the water or 

alkanol in the dispersed phase and whether the amount of dispersing 

agent had any effect on the viscosity of the dispersion. As a result, 

several sets of dispersions were prepared to resolve these questions. 

The first set (test No. 286-291) utilized 100 grams of octadecanol 

(Lorol 28) and amounts of glyceryl monostearate (self-emulsifying) 

varying from 10 to 15 percent of the amount of octadecanol used. 

The results are presented in table 6. No significant differences in 

viscosity were roted amoung the varying concentrations of glyceryl 

monostearate.

A second set of tests (test No. 292-294) utilized 10 grams of glyceryl 

monostearate to 110, 120 and 130 grams, respectively, of octadecanol 

(Lorol 28) in 1 liter of water. All separated after 48 hours of standing, indicating that the proportionate amount of emulsifier with respect to the alkanol should be 10 percent.

At first the method of cooling was to place the mixing vessel in the 

air at room temperature and stir the mixture until it cooled. If a 

jacket of cold water is placed around the vessel and stirring is continued, the mixture, of course, is cooled at a faster rate. This increased rate of cooling seems to lower the viscosity of the- dispersion 

material and also improve the spreading characteristics. When some 

of these rapidly cooled dispersions were examined under the microscope, a crystallinelike structure was observed on the solidif Qd alkanol. 

There was no indication of such a structure when dispersion material 

cooled at a slower rate was examined. However, time did not permit
LABORATORY STUDIES 11

FIGURE 3. A comparison of photomicrographs of 2.5-percent O/W, above ; and 10-percent 

W/O type dispersions, below. X 430. Photomicrographs by Southwest Research 

Institute.
12 EVAPORATION CONTROL RESEARCH, 1959-60

further work on this phenomenon, although it is apparent that more 

laboratory work is needed.

The W/O dispersions prepared by the Becher (1957) procedure, 

which requires the use of only a small amount of oil, have been quite 

fluid in nature and opaque and milky white in appearance. The O/W 

type dispersions on the other hand, have been somewhat gelatinous 

and translucent. Also, there is a distinct difference in the viscosity of 

the two types of materials. These differences between the O/W and 

the W/O dispersions were generally accepted during the course of 

this investigation as adequate evidence of the true nature of- the 

dispersions. In an attempt to confirm this, photomicrographs of 

the various dispersions were made. Several 2.5-percent O/W type 

dispersions and 10-percent W/O type dispersions were prepared and 

photographed on microscope slides at X 100 and X 430. Representative photomicrographs are shown in figure 3. Because the appearance 

of the particles under the microscope are not significantly different, 

there is some doubt as to whether the W/O type dispersion has the 

alcohol as the continuous phase. However, a dispersion using an oilsoluble blue dye, which was incorporated into the melted hexadecanol, 

was prepared. Observation of this dispersion under the microscope 

indicated the presence of some discreet particles of hexadecanol surrounding an aqueous nucleus. The contrast did not show up on the 

black and white photograph.

Although the photomicrographs of the two types of dispersions do 

not indicate that there is a difference in the viscosity of the two materials, a possible explanation of this difference based on microsopic 

observations, is that the molten alkanol first encapsulates a small 

amount of water, thereby forming a small spherical particle, perhaps 0.1 micron in diameter. On rapid cooling, these discreet particles are solidified and, because of their small size, become suspended 

in the excess water which is undoubtedly present. The fact that the 

particles are discreet and that they have the alkanol as the outer walls 

would account for the rapid spreading rate of the W/O type dispersions. In the case of the O/W type dispersions it would be necessary for the water that formed the outer walls of the capsule to be 

dispersed in the reservoir before the surface of the hexadecanol particle would be available at the reservoir surface to spread and form 

a film.

Another possible explanation for the difference in viscosities of the 

two dispersions is the phenomenon of coacervation, as described by 

DeJong (1949). In coacervation, individual solvated particles collect and form a larger particle with several individual nuclei. One 

form of coacervation is illustrated in figure 4. The makeup of the
LABORATORY STUDIES 13

a b c

FIGURE 4. A schematic diagram for the process of coacervation. (a), The alkanol 

as a loosely built macromolecular particle in the original sol. (b). The macromolecular particles have become dense and tend to associate together, (c), In 

the coacervate there are mutually associated macromolecules that penetrate each 

other at least with their peripheral loops. The particles will form polygons with 

the strongest penetration at the sides of the polygon.

boundaries for the individual nuclei or the larger particles, which 

is a collection of the smaller nuclei, is not thoroughly understood. 

The authors are not familiar enough with the theory of coacervation 

to discuss it, but have presented it only as a possible source for further 

study.

It is apparent that the W/O type dispersion borders between one 

that has a high degree of fluidity and one that is like a gelatinous 

paste. The type of dispersion formed and its stability will depend 

on the method of preparation, temperature, rate of cooling from a 

liquid to a solid, and possibly the addition of other chemicals. Before any wide use of the dispersion can be made, its form and stability in relation to these factors will certainly need further study.

As there is some doubt whether the O/W type dispersion has the 

oil as the continuous phase, the W/O type terminology has be?,n used 

for this investigation because of the significant differences described 

in the preceding paragraph.

LABORATORY CONCLUSIONS

The selection of emulsifying agents or surfactants utilized in this 

investigation was based principally on their differences in molecular 

structure. Final evaluation was made by actually preparing dispersions using various alkanols. Several empirical systems, of which 

the Hydrophile-Lipophile Balance (HLB) (table 1) is the one most 

widely used, are available to facilitate the preliminary selection of 

emulsifying agents for certain uses, such as W/O or O/W type dispersions. The HLB system has been developed chiefly by th«. Atlas

649816 O 63 2
14 EVAPORATION CONTROL RESEARCH, 1959-60

Powder Company (Griffin, 1949, 1954) for application primarily to 

their products. Some expansion of the system was possible on the 

basis of the similarity of molecular structure of Atlas emulsifying 

agents with those of various competitors. As a result of this system, 

the choice of emulsifying agents was narrowed appreciably.

It is believed that the preferred emulsifying agent, glyceryl monostearate (self-emulsifying), is sufficiently nontoxic so that its use in 

evaporation suppression will be approved by the U.S. Public Health 

Service. However, specific clearance for the material has not been 

obtained. Adequate toxicity clearance should be obtained, of course, 

before the material can be used extensively. If proper clearance 

cannot be granted for the particular composition of glyceryl monostearate, other emulsifying agents that are nontoxic possibly could 

be used.

The development of the dispersion technique has led to the possible 

use of docosanol and eicosanol as evaporation retardants, but the 

toxicity of these alkanols is uncertain. In previous studies, these 

alkanols had very poor spreading rates, but when they were in the 

dispersed form, the spreading rate was as good as octadecanol or hexadecanol. The ability of docosanol and eicosanol to resist evaporation 

is uncertain, but it is believed that they may be superior to Hxadecanol 

and octadecanol because of their longer chain.

In the laboratory experiments, the percentage of alkanols that can 

be dispersed in water or vice versa is equal to or greater than the 

amount that can be dissolved in a suitable solvent. Also, the material 

breaks up immediately upon being placed on the water surface, and 

its spreading characteristics are believed to be as good as those of 

solvents. The preparation of the dispersion is believed to be less 

costly than that of the solvent, and it also is considered to be much 

safer than solvents that are very volatile.

FIELD STUDIES

DESCRIPTION OF TEST SITES

Field studies were conducted on two 1-acre stock tanks 15 miles 

southeast of Laredo and two 1-acre stock tanks 12 miles northwest of 

Laredo, Tex. For reference purposes, the two tanks soutHast of Laredo are called Briones and Zimmerman and the two northwest of 

Laredo are called Carlos and Pinta Valle. In addition to the tank 

tests, Essar Ranch Lake, a small 10-acre lake 10 miles west of San 

Antonio, Tex., was used in the studies.

Rainfall and intermittent runoff from the small drainage basin above 

the tanks and lake contribute all of the water stored. There is 110 

provision for releasing water in storage. Therefore, tin only out-
FIELD STUDIES 15

flow from the tanks and lake are seepage and evaporation, plus the 

water consumed by the cattle and wildlife.

The material for constructing the dam for each tank is a gravelly 

clay that had been removed from the tank area. When the dam is 

completed, an excavated rectangular area, i/2 to 1 acre in size and approximately 15 feet deep, is left. The slope of the sides of this area 

are generally steep. During most of the year, all of the water stored 

in the tank is in the excavated area. Occasionally storage exceeds 

that which can be stored in the pit area, but only for short periods.

The dam for the Essar Ranch Lake is constructed with a heavy clay 

from the lake area. During the studies the level of the lake remained 

above that of the excavated area.

EVALUATION METHOD

In the field tests, the Harbeck and Koberg (1959) method was used 

to determine the effectiveness of the film in reducing evaporation. 

This method uses a combination of the energy-budget and masstransfer evaporation measurement techniques. For a specified period, 

the data that are needed to use this method consist of a measurement 

of the actual evaporation, the average wind speed, the average temperature of the water surface, and the average vapor pressure of the 

air. On the basis of these data, the savings in evaporation can be computed by substituting in the evaluation equation developed by Harbeck and Koberg (1959, p. 92). However, before the film is applied, 

a calibration period is needed to determine the coefficient for the masstransfer and conduction equations. The coefficient for the conduction 

equation is determined indirectly by the BowT en ratio. In this evaluation technique, it is assumed that for areas covered by film, a reduction in evaporation is offset by an immediate rise in temperature 

on the water surface, thus dissipating by radiation and conduction 

to the air the energy that would have been used by the evaporation. 

Later, it will be shown that the rise in temperature on the water surface takes place slowly and, as a result, energy is stored in the reservoir owing to the film.

The wind and temperature data needed for the evaluation technique 

are recorded in the following manner: The temperature of the surface 

of the water is recorded on a thermograph mounted on a raft which 

is located in the center of the tank or lake. Wind speeds are measured 

by an anemometer on the same raft on which the thermograph is 

mounted. After 10 miles of wind have moved past the anemometer, 

a tick is recorded on the margin of the thermograph chart. This is 

done by use of an electrical circuit and a solenoid. Figure 5 shows 

the raft with the instruments needed for the evaluation technique.
16 EVAPORATION CONTROL RESEARCH, 1959-60

FIGURE 5. Instrument raft showing anemometer and shelter for thermograph.

The vapor pressure of the air is determined from data furnished 

by the U.S. Weather bureau. At the tanks near Laredo, the vapor 

pressure of the air is assumed to be the same as that observed by the 

Weather Bureau at the Laredo Air Force Base. At the lake near 

San Antonio, the vapor pressure of the air is the same as that observed 

by the Weather Bureau at the San Antonio International Airport.

The actual evaporation could not be measured directly; so it was 

determined by the following method: Each tank and lake was 

equipped with a continuous water-stage recorder. For a selected period when no surface inflow, outflow or rainfall occurred, a fall in 

stage was determined. This fall in stage resulted from seepage and 

evaporation and possibly some transpiration from vegetation which, 

in this study, would be included with seepage. The theory of the 

relation between fall in stage and certain meteorological parameters 

was first presented by Langbein and others (1951). For each selected 

period, average vapor pressure difference between the air at the surface of the water and the ambient air was computed (u&e). The 

vapor pressure of the air at the water surface was considered to be that 

of saturated air and at the temperature of the surface of the water. 

For each of these same selected periods, a corresponding change in 

stage of the tank or lake (&H) was determined.

With the computed products of u&e and the respective change in 

stage, a plot of these terms can be made on graph paper with u.Ae as 

the abscissa and AH as the ordinate. After a number of points are 

plotted, a straight line can be drawn through them as illustrated in
FIELD STUDIES. 17

figure 6. If this line is extended to the ordinate axis where u&e is 

zero, the intercept on the ordinate axis is the net seepage rate. When 

the product u&e is zero, evaporation is negligible as shown in an analysis by Marciano and Harbeck (1954). The slope of the line is the 

coefficient for the mass-transfer equation.

Once the net seepage rate is defined, the evaporation rate is easily 

determined by subtracting seepage from the change in stage. For 

small stock tanks, however, the seepage rate varies with season and 

stage so that frequent calibrations are needed to define this term. For 

these studies, the wind was measured approximately 2 meters above 

the water surface and, at this height, the mass-transfer coefficient generally remains constant for all seasons and stages (Harbeck, 1958).

In the field studies, the extent of film coverage has been determined 

mostly by visual observation. These observations are based on the 

fact that whenever the wind is blowing, the surface of the water will 

ripple. If a film is present, however, the ripples are suppressed, and 

the area covered by the film can be identified. If no wind is present, 

an oil or dispersion test can be made. In this test a drop of oil or dispersion material is placed on the surface of the water, and if spreading takes place a film does not exist.

FIELD TESTS

The first field test for this report was made on the Briones stock 

pond in the spring of 1959. For this test, hexadecanol (20 percent 

by weight) dissolved in ethanol was used instead of the dispersion,

0.04 

0.03 

0.02 

0.01 

0

1

-

-

-

0.006 ft pt

y 1

1

^

r day seepag

i

 /

^'

^

^

.S^ 

DATA \ 

JULY 

E-

^"'

^LOTTED ARI 

AND AUGUS1 

-.00025 uAe

E=ft per day 

u= miles per ho 

A e= millibars

1

^>

-

-

: FROM -

f I960

ur

20 60 80 100 

PRODUCT uAe

120 160

FIGURE 6. Relation between reservoir change In stage

Pinta Valle stock tank.

and the product i*Ae for
18 EVAPORATION CONTROL RESEARCH, 1959-60

To dispense this liquid onto the surface of the water, a pressurized 

container, such as the commercial aerosol package, was used. Each 

container was filled with 75 percent by weight of the solution and 25 

percent by weight of freon (F12), which was used as the propellant to 

force the solution out of the container through the valve. Each container, when filled, contained 4 pounds of material.

Eight aerosol-type dispensers were installed around the perimeter 

of the tank as shown in figure 7. These dispensers were about 75 feet 

apart. The valve on each container was opened and closed by an electrical solenoid. The valves, which were opened intermittently for 

about 1-second duration, were controlled by an anemometer and wind 

direction vane. Depending on the direction of the wind, 1 to 4 dispensers were activated by an anemometer switch after approximately 

5/12 miles of wind had moved past the anemometer. A field investigation of the dispenser is shown in figure 8, and a schematic diagram 

of the electrical circuit which controlled the valve openings is shown 

in figure 9.

The field test of the dispenser started in February 1959 and continued through May 1959. During most of the time a considerable 

amount of electrical trouble was experienced by this system of dispensing. Some of the troubles were broken leads, poor electrical conPrevailing wind 

direction

APPROXIMATE SCALE

FIGURE 7. A sketch map of the Briones stock tank showing the location of eight

dispensers.
FIELD STUDIES 19

FIGUEB 8. An aerosol-type field dispenser which sprays the liquid material onto the surface of the water whenever the valve is opened.

9 volts -=

FIGURE 9. Diagram of the electrical circuit used to control the aerosol-type dispenser at 

Briones stock tank near Laredo, Tex.

tacts due to corrosion, and solenoids freezing due to corrosion and 

solidified hexadecanol.

Most of the liquid material, when sprayed on the surface of the 

water, solidified into a thin lens of white material. The rate of 

spreading from this lens was not as rapid as that of the subsequent 

dispersion material. Consequently, the amount of film covered by 

each dispenser was limited to small circular areas about 20 feet in 

diameter, which remained constant as it moved downwind at approximately 10 feet per minute for wind speeds of 6 miles per hour. When 

the film reached the downwind shoreline, it generally moved onto the 

shore. During very light winds, however, the film remained on the 

surface and covered the entire area of the stock tanks.
20 EVAPORATION CONTROL RESEARCH, 1959-60

During most of the test, the savings in evaporation were negligible. 

However, one period of 18 days gave a computed saving of 5 percent. 

The amount of hexadecanol applied during this period was approximately one-half pound per day per acre. The average wind speed 

was 6.8 miles per hour, the average temperature of the surface of the 

water was 81 °F, and the evaporation was 4.2 inches.

Results of this test indicate that the method of controlling the dispensers was not reliable and that the method of application by use of 

aerosol dispensers did not lend itself to rapid film formation. Consequently, some of the solid hexadecanol was deposited on the downwind shoreline because the travel time across the tank was insufficient 

for all of the hexadecanol to be used for film formation.

It was noted at the termination of the test that a large amount of 

algae and aquatic plants were growing around most of the perimeter 

of the tank. This growth extended out from the shoreline about 6 

feet. No other biological effects were observed.

Shortly after the termination of the first field test, the second test 

was started on the same tank. The number and location (fig. 7) of 

the dispensers and the electrical control system were the same as those 

of the previous test. In this test, dodecanol (Ci2 ), which is a liquid 

above temperatures of 70 °F, was used as the film-forming material. 

The minimum temperature for the test period, June through August 

1959, was never below 70°F so that solidification did not occur.

The dispensers were modified so that the liquid could move from 

the container by force of gravity rather than by a propellant. A 

field installation of this dispenser (fig. 10) consists of a gallon can 

with a copper tube running from the bottom of the can to a small 

solenoid valve. When the solenoid is energized, the value opens'and 

the dodecanol flows onto the surface of the water. The valve is controlled in the same manner as the aerosol-type dispensers with certain 

modifications in the electrical circuit as shown in figure 11. The 

modifications did not eliminate any of the previous electrical malfunctions which continued through this test.

The dodecanol spread very well when applied to the surface of the 

water. The amount of surface area covered by the film varied with 

wind speed. Generally, with winds less than 7 miles per hour, about 

three-fourths of the surface area of the tank was covered. As the 

wind speed increased to 10 miles per hour, the film area decreased to 

about one-fourth.

The results of this test were not encouraging. Most of the time 

the savings were negligible. During one 24-day period, film reduced 

evaporation by 7 percent. The actual evaporation for this period was 

5.7 inches, wind speed was 6.3 miles per hour, and the average tempera-
FIELD STUDIES 21

I'm.

EIGURB 10. A gravity-type dispenser showing the 1-gallon container at the top of the 

steel post and the solenoid valve at the bottom.

 Vane controlled

45 volts j:

150 K<J

£ |J

J200 microfarad

 0 |

b

j

 o 

°°\ "^Line

Slow release

Solenoid 

controlled

valve

relay . Line |

FIGURE 11. Diagram of the electrical circuit used to control the gravity-type dispenser 

at Briones stock tank near Laredo, Tex.

ture of the surface of the water was 85 °F. Dodecanol was applied at 

the rate of 16 pounds per day per acre.

Although dodecanol spreads very well at temperatures above 70 °F, 

the test indicates that it has very little value as an evaporation retardant. The results of the earlier screening test (Cruse and Harbeck, 

1960) had indicated that dodecanol containing significant amounts 

of hexadecanol and (or) octadecanol, was as good as hexadecanol. The 

reason for the low saving with good coverage is not known.

The large amount of aquatic growth that was present at the end of 

the first test remained through this test. The area covered by the
22 EVAPORATION CONTROL RESEARCH, 1959-60

growth did not change appreciably. No other biological effects were 

noticed even though a large amount of dodecanol was applied.

The third field test was made on the Zimmerman stock tank. This 

is the first test which utilized the dispersion as a method of applying 

the solid alkanol in a small partical size to the surface of the water. 

In this test, octadecanol was dispersed in water and stearic acid, and 

monoethanolamine was used as the emulsifier. The quantities of the 

various materials were as follows: 459 pounds of distilled water, 11.6 

pounds of octadecanol, 1.15 pounds of stearic acid, and 0.26 pound of 

monoethanolamine. The method of mixing was the same as that of 

O/W type dispersions described in the section on "Laboratory 

Studies."

To dispense the mixture, a simple equipment was used which continually dripped the dispersion material onto the surface of the water. 

The dispenser consisted of a gallon jug with a rubber stopper which 

had two holes through it. In these holes were inserted two capillary 

glass tubes having an inside diameter of 4 millimeters. One glass 

tube extended to the bottom of the jug so that when it was in an inverted position, air would be free to enter. The other glass tube was 

long enough to extend just through the rubber stopper. To regulate the rate of drip, a small wire was inserted in the short glass 

tube. The wire reduced the area of opening which in turn slowed 

down the drip rate. A field installation of the dripper is shown in 

figure 12. For this test, a drip rate of 10 drops per minute was assumed satisfactory. Because of the heterogeneity of the dispersion 

material, however, the drip rate varied considerably.

Twenty-eight dispensers were installed 20 feet apart around the 

perimeter of the Zimmerman stock tank as shown in figure 13. Each 

dispenser was installed about 8 feet from the shoreline and 2 feet 

above the surface of the water. Each drop of material would fall 

approximately 2 feet before impact with the surface of the water. 

After impact, the material remained as a drop and continued downward into the water for several inches, after which it would move back 

to the surface. What appeared on the surface, however, was only a 

small portion of the drop material, as most of it remained under the 

water surface. For spreading purposes this material is very poor 

as it remains in a drop and film formation is only along the perimeted 

of the air-water interface. If the material would break upon impact 

with the surface, the perimeter at the air-water interface would be 

increased considerably and this in turn would increase the spreading 

rate.

The field test was started near the end of June and continued 

through August 1959. During most of the time, the heterogeneity
FIELD STUDIES 23

FIGURE 12. A continuous drip dispenser installed at the Zimmerman stock tank near

I/aredo, Tex.

of the dispersion material gave considerable trouble in maintaining 

a constant drip rate. The dispensing usually started out at a fairly 

high rate of drip, but it would gradually decrease and then stop, 

though some of the dispersion material still remained in the jug.

In this test the reduction in evaporation was slightly better than 

the previous tests. For a period of 29 days, during which time very 

little rainfall occurred, the saving amounted to 12 percent. For this 

period, the wind speed averaged 4.4 miles per hour, the average temperature of the surface of the water was 87°F, and the evaporation 

was 6.5 inches. The amount of material applied was 2 pounds per 

acre per day.

The results of this test indicated that considerable improvement 

was needed in the dispersion material to increase its spreading ability. 

To obtain a good spreading rate, the drop of dispersion material must 

break up immediately upon impact with the surface of the water and 

must remain on the surface. The area covered by the film averaged 

about one-third of the surface area of the water and occasionally the 

film area would increase to about one-half.
24 EVAPORATION CONTROL RESEARCH, 1959-60

:-.-. . . -.-. .: : : : : : : : : -- ,

o o o o o

.Raft

«<^PUJ sWater-stage' r-£ta0e'

gage

O O O O O Q

Dispenser Ws*fe

Prevailing winddirection

50 50 FEET

APPROXIMATE SCALE

FIGURE 13. Location of the drip dispensers around the perimeter of the Zimmerman

stock tank.

During this test period there were no noticeable biological effects. 

The aquatic growths that were observed in the Briones tank did not 

appear in the Zimmerman tank.

The fourth field test was made on the Pinta Valle stock tank from 

October 1959 through April 1960. The use of the O/W type dispersion was continued, but hexadecanol was used instead of 

octadecanol.

The method of dispensing was changed from the continuous drip to 

a flow system which utilizes a needle valve to control the rate and time 

of flow. A sketch of this system is shown in figure 14. This sketch 

shows that the direction of the wind controls the flow of material from 

the container to the water surface and that the amount of flow is 

dependent on the opening of the needle valve. If no wind is present, 

the valve is closed by the spring. This is an improvement over the 

continuous drip system in that only the upwind dispensers allow the
FIELD STUDIES

Wind

Wind opens valve

Spring keeps valve 

closed when there 

is no wind

Needle valve

Copper tube

FIGURE 14. Sketch of wind-controlled dispenser which shows how the fluid is controlled 

from the reservoir to the surface of the water.

dispersion material to flow onto the surface of the water and move 

downwind.

The location of the 16 dispensers around the perimeter of the tank 

is shown in figure 15. The dispensers were spaced about 35 feet apart 

and each dispenser was located about 6 feet from the shoreline.
26 EVAPORATION CONTROL RESEARCH, 1959-60

Prevailing wind 

direction

50 50 FEET

FIGURE 15.-

APPROXIMATE SCALE

-A sketch of the Pinta Valle stock tank showing the 

location of wind-controlled dispensers.

During this test no significant saving in evaporation was observed, 

because the dispersion material could not flow through the dispenser. 

Either the material was too thick or the valves were continually 

clogged by small pieces of solid hexadecanol. The thickening of the 

dispersion is believed to have been caused by storing the material in 

the sunlight. Daily heating and cooling would cause some separation 

between water and hexadecanol and the separated hexadecanol would 

become very thick. Whenever the dispersion did flow through the 

dispenser, the film formation from the despersion was very slow and 

much of the material was deposited on the downwind shore without 

film formation.
FIELD STUDIES 27

No biological effects were observed, probably because of the poor 

film coverage.

The fifth field test was conducted on Pinta Valle stock tank from 

June 11 to June 30, 1960. In this test, octadecanol was applied as a 

W/O type dispersion. The quantities of material used in each sample 

prepared for field use were 50 pounds of octadecanol, 500 pounds of 

distilled water, and 5 pounds of glyceryl monostearate (self-emulsifying) . The method of mixing was the same as that of W/O type dispersions in the laboratory.

The method of dispensing was the same as that used in the previous 

test, but the container for the dispersion material was replaced by a 

5-gallon can.

In the previous test, 16 dispensers were utilized. In this test, however, only eight dispensers were necessary, because the spreading 

characteristics of the dispersion material had improved considerably 

with the change in formulation. Using the same numbering system 

as in the previous test, a dispenser was installed at each odd-numbered 

location. The even-numbered locations were not used.

The dispersion material broke up rapidly when placed on the surface of the water and formed a film much faster than the materials 

used in the previous tests. The amount of octadecanol applied was 

6 pounds per day per acre. For wind speeds of less than 5 miles per 

hour, almost complete film coverage was obtained, and at speeds of 

more than 5 miles, bands of film extended from the dispenser to the 

downwind shore. These bands varied from 10 to 50 feet in width. 

The reason for the variation in width is believed to be a function of 

wind velocity and the amount of lateral spreading before movement 

downwind began. If the material is dispensed in areas sheltered from 

the wind, a considerable amount of lateral spreading has been observed 

which in turn increases the width of the band.

The results of this test indicated a saving in evaporation of 12 percent for the complete test period of 20 days. During this time, the 

average wind speed was 7.0 miles per hour, the average temperature 

of the surface of the water was 83° F, and the evaporation was 4.3 

inches.

In addition to the film test just described, a test was made of a floating barrier to retard the loss of film to the shoreline. The barrier was 

made of plastic tubing which had an outside diameter of five-eights 

inch. In order for the tubing to hold its shape and maintain buoyancy, it was inflated with air and placed around the tank about 6 feet 

from the shoreline. Part of the floating barrier is shown in figure 16.
28 EVAPORATION CONTROL RESEARCH, 1959-60

FIGURE 16. Floating barrier installed on the Pinta Valle stock tank.

The effect of the barrier in retarding the movement of the film was 

negligible, because the film would slip underneath the barrier with 

very little loss of velocity. Thus, the use of floating barriers would 

not appreciably increase the life of the film, which is considered to 

be the time of travel of the film between the upwind and downwind 

shores.

For the fifth test, the biological effects were certainly noticeable. 

At the start of the test, very little aquatic plants and algae were observed growing in the tank. At the end of 3 weeks of treatment, however, a considerable amount of algae and aquatic plants, such as chara, 

spirogyra, and najas, were observed in the tank. Some of this growth 

is shown at the surface of the water in figure 16, which was taken at 

the end of the test. As the dispensers were between the shore and 

aquatic vegetation on the surface, the movement of the film downwind 

through the vegetation on the surface was impeded considerably.

The sixth field test was made on the Carlos stock tank. A dispersion 

of octadecanol was applied in the same manner as the fifth test. The 

quantities of material used for each sample were changed as follows: 

500 pounds of distilled water, 80 pounds of octadecanol, and 8 pounds 

of glyceryl monostearate (self-emulsifying). The method of mixing was the same as that used in the fifth test.

In this test, nine wind-controlled dispensers were installed about 50 

feet apart and about 8 feet from the shoreline (fig. 17). The test began 

on July 10, 1960, upon completion of the installation, and ended on 

July 31, 1960, when the supply of octadecanol was exhausted. The
FIELD STUDIES 29

application rate was the same as that of the previous test 6 pounds 

of octadecanol per day per acre.

The results of this test for the 22 days shows a saving of 12 percent 

in evaporation. For the test period, the evaporation was 4.8 inches, 

the average wind speed was 5.9 miles per hour, and the average temperature of the water surface was 84°F.

Prevailing wind 

direction

Water-stage^ 

gage

50 0

I i i i i i i i i i I

50 FEET

APPROXIMATE SCALE

FIGUEE 17. Sketch of Carlos stock tank showing the location of the wind-controlled

dispensers.

649816 O 63 3
30 EVAPORATION CONTROL RESEARCH, 1959-60

Film coverage was about the same as that of the other tests. The 

most significant observation of this test wT as that the w^ater in the 

tank was very turbid at the start of the test and was almost clear at 

the end. This reduction in turbidity is believed to have been caused 

by the film. However, no reasonable explanation can be offered at 

this time. The only observed biological effect was that spirogyra 

was beginning to growT in the tank.

The seventh field test wT as made on the Carlos stock tank from 

August 16 to August 27, 1960. In this test a W/O type dispersion of 

hexadecanol was applied and the nine wind-controlled dispensers wTere 

continued in use at the same locations (fig. 17). The quantities of the 

material for each sample w^ere as follows: 500 pounds of distilled 

w^ater, 45 pounds of hexadecanol, and 4.5 pounds of glyceryl monostearate (self-emulsifying). The method of mixing was the same as 

that used in the laboratory for the W/O type dispersions.

The rate of application wTas 5 pounds per day per acre and film 

coverage wTas about the same as that of the octadecanol test. However, 

it was noted that light winds collapsed the film over most of the surface area of the tank. The collapsed film wTould form small streaks of 

solid material wThich wTould tend to sink. Very little of the collapsed 

film was in evidence during the previous octadecanol test.

The results of this test wTere not as good as those of the octadecanol 

test and a reduction in evaporation of only 7 percent wTas obtained for 

a 12-day period. The poor results are believed to have been caused 

by the collapse of the hexodecanol film. During the test period, the 

average wind speed was 6.4 miles per hour, the average temperature 

of the surface of the water wT as 84°F, and the evaporation for the 

period was 2.4 inches.

A considerable amount of spirogyra wTas growing in the tank at the 

end of the test. The rapid growth of vegetation is attributed to that 

effect of the film which decreases the turbidity of the w^ater, thereby 

allowing greater penetration of sunlight for photosynthesis. The 

film also tends to increase the w^ater temperature, thus creating a more 

favorable environment for vegetal growth.

The eighth field test was made on the Carlos stock tank from September 10 to September 23, 1960. Octadecanol wT as applied as a 

W/O type dispersion and in the same quantities of material as the 

sixth test. The nine wind-controlled dispensers w^ere continued in 

use at the same locations (fig. 17) and the rate of application of 

octadecanol was 5 pounds per day per acre.

Near the end of this test the dispersion thickened to the point 

where it no longer had any fluidity. The loss of fluidity prevented 

the dispersion from flowing through the valve. Previous to this 

time the dispersion did not change its characteristics appreciably.
FIELD STUDIES 31

In field tests five through seven, the skies were generally partly 

cloudy and air temperature ranged from 80°F to 100°F. Thus the 

temperature of the dispersion material did not change appreciably. 

At the end of this test period, however, the skies were generally clear 

and the air temperature ranged from 60°F to 95°F. The material is 

believed to have thickened because the radiation from the sun was 

more intense when the sky was clear than when the sky was cloudy; 

thus, the material was heated to a higher temperature. As a result of 

the increased heating, some or all of the alkanol would be melted, 

after which it would solidify during the cool nights. The rate at 

which solidification occurs determines the fluidity characteristics of 

the material, as previously noted in the laboratory studies.

During the test, the average temperature of the water surface at 

Carlos tank was 84°F, while that at Pinta Valle tank it was 80°F a 

difference of 4°F. Also, it was observed at the end of the test that at 

9 feet below the water surface a temperature difference of 4.5°F existed between the tanks. This observation was unusual because the 

temperature difference at the surface was to be expected while that 

below the surface was expected to remain at the 0.5°F difference observed at the beginning of the test. The difference in temperature at 

the surface of the tank is believed to have been caused by the film, as 

the tanks are only 2 miles apart, and measured meteorological parameters indicate that the evaporation rate would have been nearly the 

same if no film had been applied to the Carlos tank. The difference 

in temperature below the surface was also attributed to the film.

The heating of water below the surface as a result of the film was 

never considered important until this test. To determine the magnitude of this heating in terms of energy, a computation was made to 

determine the amount of energy necessary to raise the temperature of 

the water 4°F in 14 days, assuming that the average depth of water 

in the tank is 9 feet. The computation for the test period ind; cated 

600 cal cm'2 would be necessary to raise the temperature of the water 

in the tank.

For the test period, it is of interest to determine the disposition of 

the energy which became available as a result of the reduction in 

evaporation. It has previously been computed that 600 cal cm'2 was 

used to increase the temperature of the water or increase the energy 

storage. It was also noted that the film had increased the temperature of the water surface by 4°F. From the increase in temperature, 

the amount of energy lost by back radiation and conduction to the 

atmosphere is computed to be 700 cal cm-2. The sum of these two 

items is 1300 cal cm-2 , which is the energy that would have been used 

for evaporation but was partly dissipated to the atmosphere and partly 

went into storage.
32 EVAPORATION CONTROL RESEARCH, 1959-6C

During the test period, the amount of energy utilized by evaporation at Pinta Valle was -1150 cal cm~2 . If it is assumed that this would 

have been the energy utilized by evaporation at Carlos, the reduction 

in evaporation can be determined from the above total. The percentage reduction is then computed to be 31 percent, of which almost 

half the reduction was being used to increase the amount of energy in 

storage. Another method of computing the actual evaporation reduction is by determining the evaporation difference between the 

Pinta Valle and Carlos stock tanks. The reduction in evaporation, 

based on this difference, was computed to be 27 percent, which is 

fairly close to the 31 percent reduction. The difference results from 

the uncertainty as to the exact amount of energy that went into 

storage. The method of determining the evaporation reduction based 

on the evaporation rates from the two tanks does not take into account 

the amount of energy going into storage. Upon completion of the 

test, much of the additional energy in storage is available for increasing the evaporation rate over that which would normally occur. The 

increased rate of evaporation will continue until the additional energy 

is reduced to zero. However, another important consideration should 

be given the 27 percent reduction figure. If the test had continued 

under the same meteorological conditions, then it would be logical to 

expect that energy going into storage as a result of the film would become negligible. At this point, the same percentage reduction in 

evaporation would continue, with the exception that the energy previously stored in the reservoir would now be dissipated to the atmosphere by condition and radiation.

The energy contributed to storage, as a result.o-f the film, complicates 

the problem of evaluating the reduction in evaporation by the Harbeck and Koberg (1959) technique. If a film could be applied in 

such a manner so that it would continually cover the entire water 

surface for an indefinite time, a period could be selected, for the above 

mentioned evaluation technique, that would start and end at any time 

after the temperature of the water surface had completed its rise as a 

result of the film. However, present methods of applying and maintaining the film for most reservoirs have never been completely successful in obtaining complete coverage and, even if complete film 

coverage is obtained, it can be maintained only for a short, duration 

of time. Therefore, in using the Harbeck and Koberg (1959) evaluation technique to determine the reduction in evaporation, periods 

should be selected, if possible, when the energy stored in the reservoir 

as a result of the film is not significant.

To avoid errors due to the film's storing energy in the reservoir, it 

is possible to determine reduction in evaporation by evaluating the
FIELD STUDIES 33

complete film test plus the time necessary to dissipate the energy 

stored in the reservoir by the film. The length of time for the energy 

to be dissipated after treatment is stopped should not require more 

than 2 wT eeks. Of course, when such a period is chosen, the potential 

reduction in evaporation, that is if the test had continued for an indefinite time under the same meteorological conditions, is not knowT ii, 

but it does give the actual reduction in evaporation.

In the earlier tests made near Laredo, the results obtained in 

evaporation reduction did not consider that the increase in energy 

storage, resulting from application of the film, was a significant item. 

Because the analyses did not take into account the utilization of stored 

energy in increasing evaporation as the film deteriorated, the computed 

reduction figures are probably in error; but they do serve a useful 

purpose in determining the relative effectiveness of each test.

The results of this test based 011 the difference in evaporation rates 

for the Carlos and Pinta Valle tanks indicated that a reduction in 

evaporation of 27 percent could be obtained if the conditions of the 

test prevailed indefinitely; but this does not appear practicable. For 

the test period of 14 days, the average wT iiid speed wT as 4.1 miles per 

hour and the evaporation wT as 2.1 inches.

The biological growth observed in the previous test continued 

through this test. HowT ever, this growth did not reach the surface 

of the wT ater.

The ninth field test was made 011 the Essar Ranch Lake from 

August 31 to September 22,1960. In this test, octadecaiiol was applied 

as a W/O type dispersion in the same proportions of material as in 

the sixth field test, and only seven wT iiid-controlled dispensers were 

installed instead of nine. The dispensers wT ere located about 100 feet 

apart and along one side of the lake as shown in figure 18. The rate 

of application of octadecaiiol wT as approximately 1 pound per day 

per acre.

It should be noted that the dispensers wrere twT ice as far apart and 

each band of film formed dowT iiwind wT as twT ice as wT ide as those in the 

previous tests. This difference wT as created by the position of the 

earthfill dam 011 the upwT iiid shoreline which sheltered the surface of 

the water along that shore from the wind. The sheltering effects 

allow more time for the film to move laterally from the dispenser 

before beginning its movement dowTiiwT iiid. Once this dowT iiwT iiid 

movement begins, very little lateral movement is obtained as illustrated in figure 19, which showT s a band of film extending downwind 

with a fairly constant wT idth. In this test the average wT iiid speed 

was about 5 miles per hour.
34 EVAPORATION CONTROL RESEARCH, 1959-60

|Prevailing wind 

m direction

APPROXIMATE SCALE

FIGURE 18. A sketch of the Essar Ranch Lake near San Antonio, Tex., showing the 

location of the seven dispensers.
FIELD STUDIES 35

The movement of the film was always from the upwind to the 

downwind shoreline. After reaching the shoreline, the film would 

form a white material, similar to that of the dispersion. If the white 

material was on the upwind shoreline, owing to a reversal of the wind, 

all the material would move downwind at the same time. Therefore, 

the film coverage from this material was of little value in reducing 

evaporation.

One observation noted for the first time at the Essar Ranch Lake test 

was the increase in temperature of the surface of the water as it moved 

downwind with the film. In order to obtain data on this observation 

a temperature recorder was installed 2 weeks before treatment at the 

water-stage gage (fig. 18). For this untreated period, the watersurface temperature at the raft averaged 0.6°F higher than at the 

water-stage gage. After treatment began on August 31 and until 

September 6, 1960, the average difference in temperature was 1.8°F. 

The increase in temperature between the two points of measurement 

is considered to have been caused by the film. In both periods of

FIGDKE 19. iA band of film approximately 100 feet in width extending from the upwind 

shore to the downwind shore, a distance of about 700 feet.
36 EVAPORATION CONTROL RESEARCH, 1959-60

comparison, the wind velocity and air temperature were not greatly 

different.

One possible explanation of the increase in temperature at the water 

surface as it moves downwind is the effect of ripples. In the absence 

of a film, the water at the surface is moved by the wind in the downwind direction. As the water moves downwind it is heated by incoming radiation. However, ripples and small waves tend to mix the 

water at the surface with water below the surface, so that the difference in temperature at the surface between the upwind and downwind 

shores is not greatly different. In the presence of a film, the ripples 

become suppressed; this reduces the mixing of water at the surface 

with that below. Consequently the water at the surface increases in 

temperature as it moves downwind. During the day at the Essar 

Ranch Lake, differences in temperature of 6°F have been observed 

between the upwind and downwind shores. It should be pointed out 

that the film may be multilayer downwind and a broken monolayer 

upwind, resulting in a greater temperature rise.

Another possible explanation of the increase in temperature downwind is that the wind induces circulation in the pond. The surface 

water moves downwind, causing cooler bottom water to be brought to 

the surface at the upwind shore.

For the ninth field test, results are given for the 6-day period of 

August 31 to September 6,1960, because this was the longest period in 

which rainfall did not occur. Also, the direction of wind remained 

favorable for operating the dispensers. For this period the computed 

reduction in evaporation, that is, the reduction obtained if the test 

conditions exist for an indefinite time, was 25 percent. The average 

wind speed was 4.5 miles per hour, the average temperature of the 

surface of the water was 87°F, and the evaporation was 0.9 inches.

In the ninth field test, the application rate of octadecanol per acre 

was much lower than that of the eighth test, and yet the reduction in 

the evaporation was almost the same. The reason for this was that the 

average distance of travel for the film at Essar Ranch Lake was about 

600 feet as compared with 100 feet for the Carlos stock tank, and in 

this case the ratio of distance is about the same as the ratio of the 

application rates.

No significant observations were made regarding biological changes. 

The aquatic growths that were observed in the stock tanks were also 

observed in the lake; however, these growths were believed to be present before film application started. Also, during this test, about 100 

head of prize cattle used this lake for drinking purposes but they were 

not adversely affected by the film.
FIELD STUDIES 37 

CONCLUSIONS ON FIELD TESTS

The results of the field tests indicate that some success was obtained 

in applying a monolayer to the surface of the water to reduce evaporation. The main consideration in the effectiveness of the monolayer 

was the percent reduction in evaporation. Generally, the percent 

reduction in evaporation refers to that which can be expected if the 

test conditions remain the same for an indefinite time. The economics 

of such an application have not been considered, mainly because they 

are dependent on the application rate, which in turn is dependent on 

the distance the film travels downwind. The most successful test was 

the eighth, where a reduction of 27 percent was obtained. There is no 

apparent reason why this test should be more successful than tests five 

and six, where the method and form of application were the same. 

Of course, tests five and six were not corrected for energy storage, 

but available data do not indicate any appreciable change in the energy 

storage as a result of the film.

The difference in degree of success may be attributed partly to wind 

speed. The average wind speed was 4.1 miles per hour for the eighth 

test as compared with 7.0 and 5.9 miles per hour for tests five and six, 

respectively. This would indicate that the effectiveness of tre film 

may be dependent on the speed of the wind. The relative humidity 

of the air and the temperature of the water surface may also affect the 

efficiency of the film. However, for these tests there was no appreciable difference either in the temperature of the water surface or in 

the relative humidity of the air.

The alkanols that were used to form films for these field tests were 

dodecanol, hexadecanol, and octadecanol. Of the three, octadecanol 

was the most successful in reducing evaporation. This supports the 

general belief that the longer the alkanol chain, the more efficient it is 

in retarding evaporation. The only significant difference in the alkanols observed in the field was that the film from hexadecanol collapsed 

at a lower wind speed than the film from octadecanol. The water 

temperature was 81° F during this test. It is believed that as tH temperature of the water approaches the melting point of the alkarol, the 

surface pressure at which the film will collapse decreases. However, 

there is very little laboratory data to support this theory.

Before any film can be successful, it must be applied as rapidly as it 

is lost from the surface of the water. Of the various methods of applying the film tested in the field, the wind-controlled gravity-type 

dispenser was considered better than any other method. Some of the 

desirable features of this dispenser are that the force of gravity moves 

the material from the container to the surface of the water, the direction of the wind determines when the material is to be applied to the
38 EVAPORATION CONTROL RESEARCH, 1959-60

surface, and the simplicity and low cost of construction makes it 

practical for field use. Improvements probably can be made in this 

dispenser to obtain more efficient film coverage; one such improvement 

would be to make the rate of application dependent on wind speed 

as well as wind direction. No specific rule can be recommended at 

this time concerning the interval at which dispensers should be located. 

Tests eight and nine have indicated that the exposure of the water 

surface to the wind at the point of application determines the distance 

of lateral spreading. Until more information is available on the spacing, only a trial method can be recommended to determine the distance 

of lateral spreading with respect to wind speed.

Alkanols have been applied in the field tests, as a liquid dissolved 

in ethanol, as an O/W type dispersion, and as a W/O type dispersion. Of the three forms tested, the W/O type dispersion is considered to be the most promising because of its rapid spreading rate. 

If safety and economics are also considered, it will most likely compare equally well with any other form of application. However, 

there is still a need for improving the dispersion material, especially 

in regard to viscosity and separation. The field tests have indicated 

this to be the most serious problem.

The field tests did not indicate the distance, downwind a film will 

travel and still remain effective in reducing evaporation. Test nine 

indicated the film to be still effective after traveling 600 feet. However, its effectiveness any distance beyond this point is uncertain. 

More studies are certainly needed to define the effectiveness of the film 

as it moves downwind because most reservoirs have a downwind distance that far exceeds 600 feet.

In connection with the studies on the movement of film downwind, 

the increase in temperatures of the surface of the water should also 

be studied. Test nine indicated that the increase in temperature can 

be significant. Possibly this test might be used as a method to determine the effectiveness of the film as it moves downwind.

The field tests have indicated that certain biological changes can 

be expected as a result of the film. The most noteworthy of these 

changes is the increase in growth of aquatic plants around the perimeter of the stock tank. The increase in growth is attributed to the 

rise in temperature of the water and to the decrease in turbidity which 

allows greater penetration of sunlight. No harmful effects on wildlife and cattle were observed. This does not necessarily mean that 

no harmful effects will ever arise from the presence of a film, but it 

does seem to indicate that very little, if any, harmful effect can be 

expected.
SUGGESTIONS FOR FUTURE WORK 39

In the previous study by Cruse and Harbeck (1960), it was believed 

that some destruction of the film was being caused by bacteria. In the 

present studies, the travel time of the film across the stock tanks and 

the small lake was only a matter of minutes, so the effect of the bacteria 

on the film was negligible.

The feasibility of applying monolayers to small stock tanks to 

reduce evaporation is very questionable at this time. The stock tanks 

used in the field were less than 1 acre in surface area with one exception. The amount of retardant material needed per acre to obtain 

a reduction in evaporation over a small area is much greater than 

that needed for a larger reservoir because of the shorter travel distance 

of the former. For the small stock tanks, there may be a more efficient 

and economical method of reducing evaporation. One such method is 

to place a floating cover over part of the surface of the water. The 

surface of the water would thus be open around the perimeter of the 

tank so that cattle would have access to the water. The cover could be 

constructed so that most of the solar radiation would be reflected. 

With less penetration of heat, the water in the tank presumably could 

be kept at a lower temperature. There are possibly other methods, 

but this one seems to be the most practical at this time. There may 

be some objection to a cover because it limits the use of water by wildlife, but when the total value of the water is considered, all the detrimental effects will be outweighed.

SUGGESTIONS FOR FUTURE WORK

The results of the laboratory and field work have indicated that 

more studies are needed to define or improve certain aspects in the 

use of monomolecular films in suppressing evaporation.

LABORATORY STUDIES

The effect of impurities. In the previous investigation (Cruse 

and Harbeck, 1960), it was suggested that impurities in the retardant 

materials may decrease the film's capacity to reduce evaporation. This 

problem has not been resolved, and a fundamental laboratory st'idy on 

this aspect is still needed.

In addition, it has been noted in the course of this investigation 

that hexadecanol gives dispersions having somewhat different viscosity 

properties from the octadecanol or eicosanol. Some preliminary work 

by Arista Industries (written communication, 1960) utilizing gasphase chromotography indicates the presence of undetermined impurities in various hexadecanol compositions sold by this company. 

Even in previous work (Cruse and Harbeck, 1960) hexadecanol
40 EVAPORATION CONTROL RESEARCH, 1959-60

seems to behave somewhat differently from the octadecanol, when 

used as a solid.

These phenomenon suggest that hexadecanol contains impurities 

which are originally formed as a result of the hydrogenation of vegetable oil or animal fat, and which distill, codistill, or azeotropically 

distill in the same range (316° to 336° C) as does the hexadecanol. 

The determination and characterization of these impurities could best 

be clone by vapor phase chromotography, also, comparative determinations could be made for octadecanol and the higher homologs.

Polymorphism of long chain, alkan-ols. Vines and Meakins (1959) 

have described phase transformation in commercial hexadecanols used 

for water conservation. The studies indicated that phase transformation occurs at about 30° to 40°C and that it affects the ability of the 

material to spread. In the course of this investigation, it has been 

noted that when a W/O type dispersion is cooled rapidly, it has better 

spreading properties than a similar dispersion which is not cooled 

rapidly. Further, if the material had been allowed to stand at 

temperatures about 90°F, thickening of the dispersion would haveoccurred with attendant difficulties in the application procedure. 

These observations indicate that both hexadecanol and perhaps the 

homologous series from Ci2 or Cu to C22 possess polymorphic properties. Fundamental laboratory studies of the problems of the rate 

of cooling and the effect of storage are needed for a better understanding of this phenomenon.

The effect of relative humidity. In the theoretical discussions it 

was pointed out that the film retards the movement of water molecules 

from the water as well as from the atmosphere above the film to the 

water. Laboratory studies are needed to define this aspect with regard to the relative humidity of the air and the surface pressure of 

the film.

FIELD STUDIES

The effect of the wind. In the course of this investigation it has 

been demonstrated that the rate and direction of movement of the film 

are dependent on the wind. Studies are needed to define the distance 

downwind the film remains effective and also whether the f 1m remains 

effective regardless of the rate of movement. In addition, the lateral 

movement of the film should be defined with respect to wind speed.

Use of docosanol and eicosanol. Laboratory studies have indicated 

that docosanol and eicosanol have the same spreading characteristics, 

when they are in the W/O type dispersion form, as hexadecanol and 

octadecanol. Field studies are needed to determine whether higher 

reduction in evaporation can be obtained with the longer chain 

alkanols.
SUGGESTIONS FOR FUTURE WORK 41

Increase in temperature of the surface of trader, Further studies 

are needed to determine whether the rate of increase in the temperature of water at the surface is an index of the effectiveness of the 

film in reducing evaporation.

Other possible methods to reduce evaporation, An investigation 

is considered warranted in the use of reflective solar cover as a method 

of reducing evaporation from small stock tanks. Preliminary studies 

indicate that the percent of water-surface area coverage is an indication of the reduction in evaporation.

Other possible uses of alkanoh. In Japan, dispersions of alkanols 

are being used to increase the temperature of water in the rice paddies 

to mature the crop at an earlier date. This dispersion mateiial has 

also been applied to irrigation water. By this application, r monomolecular film is left on the soil which presumably reduces the evaporation loss from the soil.
42 EVAPORATION CONTROL RESEARCH, 1959-60 

REFERENCES CITED

Becher, P., 1955, Principles of emulsion technology: New York, Beinhold Publishing Corp., 149 p.

 1957, Emulsions: Theory and practice: New York, Reinhold Publishing

Corp., 382 p. 

Cruse, R. R., and Harbeck, G. E., 1960, Evaporation control research 1955-58:

U.S. Geol. Survey Water-Supply Paper 1480, 45 p., 1 pi., 14 figs. 

DeJong, H. G. B., 1949, Crystallization-coacervation-flocculation, chap. 8 in

Kruyt, H. R., ed., Reversible systems, v. 2 of Colloid- science: New York,

Reinhold Publishing Co., Inc., p. 243-248. 

Griffin, W. C., 1949, Calculations of "HLB" values of nonionic surfactants:

Cosmetic Chemists Soc., v. 1, p. 311.

 1954, Calculations of "HLB" values of nonionic surfactants: Cosmetic 

Chemists Soc. Jour., p. 249-256.

Harbeck, G. E., 1958, Mass-transfer studies in Water-loss investigations: Lake 

Mead studies: U.S. Geol. Survey Prof. Paper 298, p. 29-35.

Harbeck, G. E., and Koberg, G. E., 1959, A method of evaluating the effect of a 

monomolecular film in suppressing reservoir evaporation: Jour. Geophysical 

Research, v. 64, no. 1, p. 89-93.

Harkins, W. D., 1952, The physical chemistry of surface films: New York, Reinhold Publishing Corp., 413 p.

Langbein, W. B., Hains, C. H., and Culler, R. C., 1951, Hydrology of stockwater reservoirs in Arizona: U.S. Geol. Survey Circ. 110, 18 p., 12 figs.

McArthur, I. K. H., and Durham, K., 1957, The influence of dosage on the 

efficiency of films of fatty alcohols for water conservation: Research, v. 10, 

p. 291-292.

Mansfield, W. W., 1955, Summary of field trials on the use of cetyl alcohol to 

restrict evaporation from open storage during the season 1954-55: Commonwealth Scientific and Industrial Research Organization, Div. of Indus. 

Chemistry, serial 74, 8 p., Melbourne, Australia.

Marciano, J. J., and Harbeck, G. E., 1954, Mass-transfer studies in Water-loss 

investigations: Lake Hefner studies, technical report: U.S. Geol. Survey 

Prof. Paper 269, p. 46-70.

Rideal, E. K., 1925, The influence of thin surface films on the evaporation of 

water : Jour. Phys. Chemistry, v. 29, p. 1585-1588.

Rosano, H. L., and La Mer, V. K., 1956, The rate of evaporation of water through 

monolayers of esters, acids and alcohols: Jour. Phys. Chemistry, v. 60, p. 

348-353.

Vines, R. G., and Meakins, R. J., 1959, Phase transformation in commercial cetyl 

alcohols for water conservation: Australian Jour. Applied Science, v. 10, 

no. 2, p. 190-200.
TABLES

TABLES 45 

TABLE 1. Emulsifiers available for evaluation with water evaporation retarlants

Type structure or formula Trade name HydrophilvLipophile Ba'ance

Aralkyl sulfonate (90 percent active) __________

Aralkjrl sulfonate (31.5 percent active)_________

Sorbitan monolaurate....- ___________

Sorbitan monostearate__..... ___________

Glyceryl monostearate (self-emulsifying)__------- 

Sorbitan oleate. ______________________

Polyoxyethylene stearate _.... 

stearate_________________

sorbitan monopalmitate_______

sorbitan monostearate................

Polypropylene glycol monostearate___ _______.

Cla-Cl8 Alkanols, with 10 percent lauryl sulfate........

Nonyl phenoxy polyoxyethylene ethanol condensation 

^product.

Nonylphenol-polyoxyethylene condensation product...

Alkyl oxazoline_____ ___ ___________

Alkyl oxazoline_________ _____ _______.

'2-amino-2-methyl-l-Dropanol______________.

Polyoxyethylene-alkylphenol condensation product....

Sodium-N-methyl-N-alkyl taurate.....................

Sodium lauryl sarcosinate..___________....

Oleylsarcosine.-.__________.................

Aralkyl sulfonate-polyoxyethylene condensation product.

Alkyl imidazole-N-carboxymethyl-N-hydroxy-N-hydroxyethyl sodium salt.

Alkyl imidazole-N-carboxymethyl-N-hydroxy-N-hydroxyethyl sodium salt.

Cetyl betaine (Aqueous).___________........

Aralkyl sulfonate________________........

Fatty alkylolamide_________..____........

Fatty alkylolamide....................................

Fatty alkylolamide (modified)______________

Alkyl phenol-polyoxyethylene condensation product 

(5 mo Is).

Alkyl phenol-polyoxyethylene condensation product 

(7 mo Is).

Alkyl phenol-polyoxyethylene condensation product 

(9 mols).

Alkyl phenol-polyoxyethylene condensation product 

(10 mols).

Alkyl phenol-polyoxyethylene condensation product 

(15 mols).

Alkyl phenol-polyoxyethylene condensation product 

(30 mols).

Aralkyl sulfonic acid..._____________.......

Alkyl phenol-polyoxyethylene condensation product...

Alkyl sulfate (modified)-.-__--_---------_--...

Alkyl sulfate (ammonium).._.____________

Alkyl sulfate (sodium)..... - ____________

Stearyldimethylbenzylammonium chloride............

Isooctyl phenol-polyoxyethylene condensation productAlkanolamide.______________________

Alkanolamide.._____________________

Lauryl sulfate+aralkyl sulfonate+amine condensates 

+EDTA.

Modified alkanolamide condensate..._____.......

Alkyl phenol-polyoxyethylene-ammonium sulfate condensation product.

Structure unknown_____________..........

Structure unknown______________..........

Tridecanol polyglycol ether sulfate (Na salt)-.........

Tridecanol polyglycol ether sulfate (NH4 salt).____

Tridecanol polyglycol ether sulfate (Triethanolamine 

salt).

Lauryl diethanolamide_____.......................

Alkyl phenol-polyoxyethylene-iodine complex condensate.

Alkanolamine-fatty acid condensate -__.............

acid condensate-__.............

Nonylphenol Polyoxyethylene condensate-... ...

Triethanolamine lauryl sulfate (40 percent).........

Sodium alkylnaphthalene sulfonate- .............

Dioctyl ester of sulfosuccinic acid__________.

Ultra wet KX-... 

Ultrawet 35KX-. 

Arlacel (Span) 20- 

Arlacel (Span) 60. 

Arlacel 165 

Atpet200--- ... 

O-2151---_......

MYRJ45----.--

Tween40--_._.. 

TweenBO---.__

11.7

8.6

4.7

5.5

4.3

16.0

11.1

15.6

14.9

Deyhydag Wax SXIgepal CO-210. 

Igepal CO-880.. 

Alkaterge C_______. 

Alkaterge T___....--.

2-AMP (with fatty acid). 

Tergitol NP-14 ... 

Tauranol ML_____... 

Sarkosyl NL-30.___... 

SarkosylO .. -........

Nacconal NRSF.........

Miranol CM, Conc. 

Miranol SM, Conc.

Product BCD.__. 

Agrimul 89_____. 

Hyonic FA-20......

Hyonic FA-40..- 

Hyonic FA-75......

Hyonic PE-50...--.

Hyonic PE-70......

Hyonic PE-90... 

Hyonic PE-100.....

Hyonic PE-150...-. 

Hyonic PE-300.....

ABS-99 .....

Kyro EO-.__. 

Orvus ES ...--. 

Orvus K-___.. 

Orvus WA . 

Pendit CA.......

Triton X-100....

Roterge DC-100. 

Roterge 100-M... 

RokylSC.......

12.8 (esti-nated) 

13.1 (esti-nated)

40

Surfact-Co MA. 

Surco 57- _---

Surco HAB__.. 

Surco LD-119..... 

Trepenol S-30-T-. 

Trepenol A-60-T.. 

Trepenol T-100-T.

Trepoline LM-46-. 

Biopal VRO-20...

Onyx-01 9162-_._.....

Onyx-01 336--- ---------

Neutronyx600...__....

Maproflx TLS-500.......

Sorolene G___.........

Aerosol OT (100 percent).

649816 O 63 4
46 EVAPORATION CONTROL RESEARCH, 1959-SO

TABLE 1. Emulsifiers available for evaluation with irater evaporation 

retardants Continued

Type structure or formula

and antioxidant.

Trade name

G-2151 (MYKJ-51).. ....... ..

G-3300.. ___ --.- -. ___ ..--.

Arlacel (Span) 80__-__ ...

Arista No. 6014 

SLS-11 -

TEA-LS _.. --

MEA-LS - ... -----

G-1726 

G-263 

G-271. 

Emulphor UN-430. ......

Hydrophile-Lipophile Balance

16.0

11.7

4.3

15.0

5

3.7

30

25-30

TABLE 2. Water-in-oil emulsions usvng 250 grams of dodeoanol as the oil

Test

1- ......

3 .......

4 ... __

5 .......

6 .......

Emulsifying agent

Amount of 

emulsifying agent 

(grams)

25

oc

25

25

25

25

Remarks

after 24 hr.

cent separated afi*r 24 hr.

stable after 24 hr. Set to paste.

TABLE 3. Oil-in-water dispersions of alkanols

Test

7. ......

8.......

9.......

10......

11------

12__..-

13-.-...

14..-..-

Oil phase

Alkanol

Octadecanol . . 

 -do-. 

- do-.. 

..-..do-..,. 

. --do..-. 

 do... 

----do-- 

... -do-.. 

Amount 

(grams)

25 

25 

25

25

25 

25 

25 

25

Dispersing agent

Type

Glyceryl monostearate, 

self -emulsifying.

 ..do--. 

 do-. 

Aralkyl sulfonate (Ultrawet KX). 

 do.- 

-. do..-- . 

 do..... ......

Amount 

(grams)

2.5 

5.0

7.5

10.0

2.5 

5.0 

7.5 

10.0

Water 

(milliliters)

1,000 

1,000 

1,000

1,000

1,000 

1,000 

1,000 

1,000

Remarks

Separated, 1-in. oil layer.

Separated, IM-in. oil 

Iryer. 

Separated, 1^-in. oil 

Iryer, IJ^-in. foam 

Iryer. 

Separated, lH-in. oil 

Iryer, l}<j-in. foam 

Ipyer. 

Separated, ^i-in. oil layer

Separated, 1^-in. oil 

layer. 

Separated, 2^-in. oil 

layer. 

Separated, IM-in. oil 

layer, 3^-in. foam layer.
TABLES 47

TABLE 3. Oil-in-water dispersions of alkanols Continued

Test

15__ _

16.. 

17 -----

18. 

19- 

20.. 

21..-.-

22.. 

23.- 

24.. 

25.. 

26.. .

27-. -

28.. -

29.. 

30-- 

31.. 

32.. 

33-- 

34 

35 -

36. 

37 -

38 

39 

40 

41 

43 -

44. .

45 

46 

47 

48 

49 -

50 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

Oil phase

Alkanol

OctadecanoL. 

._-do__. ....

....do... _._.

 do... .

 _do.-_._. _.

 .do.. _.

 do.. 

.... do.. 

 do... ....

 do.-- 

 do... .

.-..do.-.. .

 _do_- _

 do... 

 .do.- .. .

... .do.. _

 do... 

- .do.. ......

 do... 

 -do... ... ...

 -do ... ...

... ..do... ......

... ..do .

... ..do .....

 do .....

 - do 

 ..do .

 .do .

 do 

... ..do ...

 ..do 

 do ---

 - do ...

- do . -.

 -do .

 -do 

..... do... 

 do 

 dO 

 dO 

 do... 

 do 

 .do . 

 -do 

 -dO .....

 dO 

.... .do.... .....

Amount 

(grams)

25 

25 

12.5

12.5

12.5

12.5 

25

25 

25

25 

25

25 

25

25 

25

25 

25

25 

50

25

25

25

25

25 

25

25

25 

25

25

25

25 

25

25

25 

25

25

25

25 

25

25

25

25

Dispersing agent

Type

Cetyl betaine, (Aqueous). 

 do.-- . ... 

 do.-.. -

....do.- 

....do.-.. ... 

 do.. 

Polyoxyethylene sorbitan monopalmitate 

(Tween 40). 

 do.. ... 

 do.. .

... do... .... ...

Polyoxyethylene sorbitan monostearate. 

 do.-.. 

 do.. 

 do.-. 

Nonyl phenoxy polyoxyethylene ethanol. 

 do... ... .... _

+ 2-amino-2-methyl1-propanol.

+ monoethanolamine. 

 do.. --- 

Aralkyl sulfonate _ . ... 

 . do.... ....... ........

..... do ..... ........

 -do__... ... ..

Sorbitan monolaurate 

(Arlacel20). 

 do ..... ... 

 do ... ... ... 

 .do... ...... 

Alkyl phenol-polyoxyethylene condensation 

product. 

 do .... .... .... .

- do ... ..... ......

Alkyl pheno-polyoxyethylene condensation 

product. 

Sodium lauryl sarcosinate. 

... ..do 

 do 

 - .dO ... ...... 

Oleyl sarcosine (sarkosvlO). 

 .do . .

 ..dO 

 .dO 

Aralkvl sulfonic acid 

(ABS-99).

 do ..... 

 .dO ..... ..........

 -dO 

Alkyl oxazoline (Alkaterge C). 

__ do _ . ..___..._. 

. dO .

-...do ...... ..... ...

Amount 

(grams)

1.75 

2.5 

3.75

5.0 

1.75

2.5 

2.5

5.0 

7.5

10.0 

2.5

5.0 

7.5

10.0 

2.5

5.0 

2.5 

1.5

2.5 

1.0

5.0 

2.0

2.5 

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0

5.0 

7.5 

10.0

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0

Water (milliliters)

1,000 

1,000 

500

500 

500

500 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000

1,000

1,000 1, 000" 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000

Remarks

Separated, 2-in. oil layer, 

3 4-in. foam layer. 

Separated, 2-in. oil layer, 

'fin. foam layer. 

3 |-in. foam, no other 

separation. 

Separated, 3 layers. 

Separated, 1M-'H- oil 

layer. 

1-in. foam, no other 

separation. 

Separated, J 2-in. oil 

layer.

Separated, 3 layers, 1?2- 

in. oil layer. 

Foamy, but no aoparent 

separation. 

Separated, 3 layers. 

Separated, J-rin. oil 

layer. 

Do. 

Separated, 3 layers, 1^2- 

in. oil layer. 

Do. 

Separated immec1 lately.

Do.

Stable dispersior ; somewhat more viscous 

than desired af.er 24 hr 

standing. 

Excellent stable dispersion; good viscosity 

characteristics. 

An attempt to increase 

the concentration of 

the octadecancl to 50 

g/ per . Diversion 

could be used, but was 

quite viscous. 

Separated. 

Do. 

Do. 

Do. 

Do.

Do.

Separated, some foam. 

Do. 

Separated.

Do. 

Do. 

Do.

Do.

Good, stable dispersion. 

Do. 

Separated. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do.
48 EVAPORATION CONTROL RESEARCH, 1959-fO

TABLE 3. Oil-in-icater dispersions of alkanols Continued

Test

62... _ .

63.......

64.......

65... ...

66.......

67 

68- 

69.......

70 

71-. .

72. 

73 

74 

75 

76 .

77 ... .

78. -.

79 

80 

81 

82 

83. .

84 

85 -

86 

87 

88 

89 

90 

91 -

92 __..

93 

94 

95. 

96 .. 

97. 

98 

99 

100 .

101 

102 

103 ..

104 

105 -. 

106_ ._

107 

108 

109 --

110 -

111 ...

112 ...

113 .

Oil phase

Alkanol

Octadecanol-. 

 ..do ... .

 -do.........

 - do ....

 ..do. .....

..-.do ... ...

 -do ......

 .do ..

-- do ...

 do _. 

- do ....

 do .... ,

---.do.- .

 -do 

- do_____ 

 -do 

 -do .

 .do 

-- do .---

 .do . 

- do 

 -do -

 -do 

- do... ... ...

 -do 

---.do ....

- do ..

- do .-..

--- do ......

 -do... 

 do... ... ...

. .do ...

-- do 

- do -...

...-do ..... . 

- do ...-_

 -do ... ...

 ..do ...

 do .

- .do 

- do .._ 

 -do 

- .do -___

- .-do ..-_-_ 

- do -

----.do... ._...

-....do _--_-

 -do 

--..do ...

 . -do -..-_

 .do 

- do... ... ...

Amount 

(grams)

12.5 

12.5

12.5

12.5

12.5 

12.5

12.5

12.5

25 

25 

25 

25 

12.5

12.5

12.5

12.5

25

25

25 

25

25

25 

25 

25 

12.5

12.5

12.5

12.5

25

25 

25 

25 

12.5

12.5

12.5 

12.5

25 

25 

25 

25 

12.5

12.5

12.5

12.5 

25

25 

25

25 

25

25 

25 

25

Dispersing agent

Type

Polyoxyethylene-alkyl 

phenol condensation 

product. 

 -do ... ... ...

 ..do ..... . ...

.... .do .. ... Sodium-N-methyl-Nalkyl taurate. 

 ..do ... .... ..... ....

-...do ..... ... ... 

- do .-- . 

- do._ .. __ . _ ._ 

 .do... ... 

 -do ... ... ... ... ...

Isoctyl phenol-polyoryethylene condensation product.

- do .. 

. do .. - 

Alkyl imidazole-N-carboxyme th yl-N-h ydroxy-N-h ydroxyethyl sodium salt.

 . .do . -_-.-.--

 .do -.- - 

Imidazole derivative 

(Miranol SM) 

-.-do ...... .... 

- do __ _- 

 do .

Tridecanol polyglycol 

ether sulfate, Na salt. 

... -do ..- . -_

 -do 

- do _. _

Tridecanol polyglycol 

ether sulfate, NHi 

salt, 

-. do ... ... 

 -do ... .

 do -

Alkylphenol-polyory- 

,ethylene condensate; 

iodine complex. 

Alkylphenol-polyoxyethylene iodine complex condensate. 

 -do _. - 

 ..do .. . 

Mixture (Rokyl SC).-_

 -do . . ..

 ..do . -. - 

Alkanolamide (Roterge 

100-M).

.. do ..... ------

.._-_do_ ----------- 

Alkanolamide (Roterge 

DC -100). 

 do ..

 do . -- .

-- do . - -----

Alkanolamide (Hyonic 

FA-20).

 .do . 

 ..do -. - .

Amount 

(grams)

1.75

2.5 

3.75 

5.0 

1.75

2.5 

3.75 

5.0 

2.5 

5.0 

10.0 

10.0 

1.75

2.5 

3.75 

5.0 

2.5

5.0

7.5 

10.0

2.5

5.0

7.5 

10.0 

1.75

2.5 

3.75 

5.0 

2.5

5.0 

7.5 

10.0 

1.75

2.5

3.75 

5.0 

2.5 

5.0 

7.5 

10.0 

1.75

2.5 

3.75 

5.0 

2.5

5.0

7.5

10.0 

2.5

5.0 

7.5 

10.0

Water (milliliters)

500

500 

500 

500 

500

500 

500 

500 

1,000 

1,000 

1,000 

1,000 

500

500 

500 

500 

1,000

1,000

1,000 

1,000

1,000

1,000 

1,000 

1,000 

500

500 

500 

500 

1,000

1,000 

1,000 

1,000 

500

500

500 

500 

1,000 

1,000 

1,000 

1,000 

500

500 

500 

500 

1,000

1,000 

1,000

1,000 

1,000

1,000 

1,000 

1,000

Remarks

Separated.

Do. 

Do. 

Do. 

Good, stable dispersion.

Do. 

Do. 

Do. 

Separated. 

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Fairly good, stable dispersion. 

Qool, stable dispersion. 

Excellent, stable dispersion. 

Separated.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do.

Do. 

Do. 

Do. 

Do. 

Gooi, stable dispersion. 

Do. 

Excellent dispersion.

Do. 

Do. 

Do.

Very good, stable dispersion. 

Do. 

Excellent, stable dispersion. 

Do. 

Separated.

Do. 

Do. 

Do.
TABLES 49

TABLE 3. Oil-in-water dispersions of alJcanols Continued

Test

114 

115 

116 

117 

118 

119......

120 

121 ...

122 

123 

124 

125 

126 -

127 

128 -

129_._.-_

130 -

131 

132 

133 .-

134 

135 

136 

137 .

138 

139 

140 

141 

142 

143 

144 

145 

146 . 

147 

148 

149 

150 .

151 

152 

153 

154 

155 

157. 

158 .-

159 

160 

161 

162 

163 

164 

165 

166 

167 

168 

170 

171 

172 

173 

174 

175 

Oil phase

Alkanol

Octadecanol... 

--.do- .......

. . do --_

-..-do __

. do- .....

 -do ___

 do ...

-- do ..

----.do ..

---do _

- .do,. ... -

---do- .....

 .do ..

- .do _..

. .do. ....

. .do-

 .do 

- do. 

--..do .... ..

-- do ...

-.--.do. .....

-. do-

 .do ...

-- do... ......

 - -do.... ... -

 do....... .

 do.,.. .

 do.. ......

 -do.__ 

 do........

 do... 

- do.. ......

 ..do........

 .do.... 

- do_. ______

 - do... 

 do..-- 

 do..-. .

-__~do_____ 

 .. do.... 

- do.... 

 .do.-.. 

 do........

.---do-... .

 do........

 do.__._ 

- do.---...

 do.,....-.

 -do.... 

 _ do,. ......

 do..... 

 -do... _ 

- do.... 

 .do.,.. 

-_-do.__ 

----do.-.--,..

---do.......

 - do..... 

 -do..... 

 . do.... 

- do-.... 

 do... 

Amount 

(grams)

25

25 

12.5

12.5

12.5

12.5

25 

25 

25 

25

25

25 

25 

25 

25 

25 

25 

25 

25 

25 

25 

25 

25 

25 

25

12.5

12.5

12.5

12.5

25 

25 

25

25

25

25

25 

25

12.5 

12.5

12.5

12.5

12.5

12.5

12.5 

12.5

25 

25

25 

25 

25

25

25

12.5 

12.5

12.5

12.5

Dispersing agent

Type

Alkanolamide (Hyonic 

FA-10). 

 . .do.... . 

- do. 

 _do _. 

-...do ..- -.

__...do _. ------

 do 

 do 

 _do 

Alkyl phenol-polyoxyethylene condensation 

production.

 .do...... .

-..-do - - 

- do --- ..

--.do -- .

 _do 

 .do 

---.do... -------

-. do... . .

 do...... .

.....do ._- .

... ..do 

 .do. 

... -.do - 

..... do....... ... ........

..... do...-. ..... ....

 do.... .... ......

 .do....... .... ... ....

 do.. ....... ......

Alkyl sulfate (modified) . 

 - do........ . ......

 .do..- .... ......

_-_-. do..... ...... ....

 do.... .... .......

 do..-.- .......

 - do.... ........

Alkyl sulfate (ammonium) . 

 .. do.... .... .

..... do.... .... ......

 .do...-. ... ......

 . do... ..... 

 do.. .. -. 

.-..do-.-- ....

Modified alkanolamide. 

 -do.... ...... .....

 ..do---- .... ......

. do..-- ... ....

Alkyl phenol-polyoxyethylene-ammonium 

sulfate condensation 

product. 

 -do-... 

 do.... .... .... 

 do.-...-- .....

Modified alkanolamide. 

 .do.-.-.. .

 do . 

 .do-..-. ... ....

 -do... 

.... . do.... ....... ...

.- do ...... .....

..... do-.. ... ..... ...

Amount 

(grams)

1.75

2.5 

3.75

5.0 

1.25 

2.5 

2.5 

5.0 

7.5 

10.0

2.5

5.0 

7.5 

10.0 

2.5 

5.0 

7.5 

10.0 

2.5 

5.0 

7.5 

10.0 

2.5 

5.0 

7.5 

10.0 

1.75 

2.5 

3.75 

5.0 

2.5 

5.0 

7.5 

10.0

2.5 

5.0 

7.5 

10.0 

2.5

5.0

7.5

10.0

1.25 

2.5 

3.75 

5.0 

1.25 

2.5 

3.75 

5.0 

2.5

5.0 

7.5 

10.0 

2.5 

5.0 

7.5 

10.0 

1.25 

2.5 

3.75 

5.0

Water (milliliters)

500

500 

500

500 

500 

500 

1,000 

1,000 

1,000 

1,000

1,000

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

500 

500 

500 

500 

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000 

1,000

1,000 

1,000

1,000

500 

500 

500 

500 

500 

500 

500 

500 

1,000

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

500 

500 

500 

500

Remarks

Gelled.

Do.

Very good, stable dispersion. 

Do. 

Do. 

Do. 

Separated. 

Do. 

Good, stable dispersion. 

Very good, stable dispersion. 

Separated.

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Good, stable dispersion. 

Do. 

Do. 

Very good, stable dispersion. 

Separated. 

Do. 

Do. 

Do. 

Do.

Do.

Very good, stable dispersion. 

Excellent, stable dispersion. 

Separated. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do.
50 EVAPORATION CONTROL RESEARCH, 1959-60

TABLE 3. Oil-in-water dispersions of alkanols Continued

Test

176 

177 

178 

179 ...

180 

181-. ...

182......

183 

184......

185......

186... ...

187 

188 

189 

190 

191 

192 

193 

194 

195 

196 

197 

198 -

199 

200 

201 

202 

203 

204 

205 

206 .

207- 

208 

209- _

210. 

211 _

212 ,

213 

214 

215 -

216- -

217_ 

218 

219 -

220 

221 -

222. ...

Oil phase

Alkanol

Octadecanol _ 

. .do........

.... .do.. ......

 -do.. ......

. -.do ...

.... .do ... ...

 .do _. 

 -do ..... .

 do.. .

.... .do 

 do ....

 -do.... ..... 

 .do .....

 . do... ..... . 

 .do. .

 .do.... .....

Dodecanol.. 

.... .do 

 .do. .

Octadecanol ...

.... .do ...

 .do ..... . 

. do ......

 . .do .....

 do.. .

- .do ....

 do 

 -do... 

 -do 

 do ......

 do 

HexadecanoL . 

 _do .

 -do 

 do 

 - do -

 -do -

 -do... 

--..do . 

. .do 

 do 

 -do... 

---do _

 -do ....

 -do 

 .do .....

 do .

Amount 

(grams)

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

50 

100 

25 

25 

25 

25 

25

25 

25 

25 

25

25 

25

 25

25

26

25 

25 

25

25 

25

25

25 

25

25 

25 

25 

25 

25 

25

Dispersing agent

Type

Triethanolamine lauryl 

sulfate. 

. do..... _ 

. do..... ... ..

- do ..

Sodium alkylnaphthasulfonate. 

 do... 

 .do. . ...... 

 .do ......

Alkanols+lauryl sulfate 

...-do . ............ ...

.... .do ... ... ... ......

 do...... .... ...

Dioctyl ester of sulfosuccinic. 

 .do... ....... ... ......

 do .... .... ..... ...

 .. do ... ... ... ...

Monoethanolamine stearate. 

..... do.... ... ... ... ... ...

 .do .... 

Lauryl diethanolamide..

 do ...... ...... ....

 . -do .... ...... 

Aralkyl sulfonate-polyoxyethylene condensation product.

- do .. 

 - do 

Nonylphenol-polyoxyethylene condensation 

product.

 .do 

..-..do . . . . 

Fatty acid derivative of 

polypeptide; Ksalt.

 .do . 

---.. do ..- -------

 .do ..... 

Fatty acid derivative of 

polypeptide; Na salt.

---do . . -

.... .do 

Polyethylene stearate. . .

--.do ----------

--.-do ------------

-.--do .... ... 

 do ..-. 

Amount 

(grams)

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

10.0 

2.5 

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0

7.5

10.0

2.5 

5.0

7.5 

10.0 

2.5 

2.5 

2.5 

2.5

Water 

(miniliters)

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000

1,000

1,000 

1,000

1,000 

1,000 

1,000 

1,000 

1,000 

1,000

Kemarks

Good, stable dispersion.

Do. 

Do. 

Good, stable dispersion. 

Separated. 

Do. 

Do. 

Do.

Separated; material a 

self-dispersing formulation. 

Do. 

Do. 

Do. 

Separated.

Do. 

Do. 

Do. 

Stable emulsion

Do. 

Do. 

Separated. 

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do.

Excellent, stable dispersion.

Excellent, stable dispersion, viscosity 

greater than 203. 

Excellent, stable dispersion, viscosity 

greater than 204. 

Excellent, stable dispersion, viscosity 

greater than 205. 

Quite liquid; some foam 

separated, but otherw'^e appears quite 

stable. 

Good, stable dispersions, 

vhcosity>207. 

Gocd, stable dispersions, 

viseosity>208. 

Good, stable dispersions, 

viscosity>209. 

Separated; quite fluid.

Good, stable dispersion. 

Good, stable dispersion, 

viscosity>212. 

Gocd, stable dispersion, 

viscosity>213. 

Separated. 

Fair dispersion, some 

foim separation. 

Do. 

Separated. 

Do. 

Do. 

Do. 

Do.
TABLES 51

TABLE 3. Oil-in-water dispersions of alkanols Continued

Test

223......

224 

226__.._.

227 

228 

229......

230 _ 

231 

232. 

233 

234 

235 

236 

237 

238 

239......

240 -

241......

242 

243 ....

244 

245 .

246 

247. - ..

248 

249__....

250 

251 

252 

253. 

254 -

259 

260 

Oil phase

Alkanol

Hexadecanol 

 ..do. .....

 .. do 

...-.do........

 ..do .....

~ do..... 

-- do__ -_

- -do .

 do 

 do .. .

 -do- ...

-- do 

 . -do ... .-

-.-do... .... ._

 ..do .... -

.... .do.........

.....do.........

.. do. . .

 ..do ..

- do. .

 -do ....

. do ..

 . .do -

 do. 

 _ do ... ..

 -do 

----do ...

---do 

 do ....

-- do... .... ._

 -. do__. ... ...

 do 

 -do.........

--.do... .... ._

Amount 

(grams)

25

25 

25

25 

25 

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

25

25 

25 

25 

30

35

Dispersing agent

Type

Polyoxyethleue stearate 

(MYRJ45). 

 ..do ... ...... -----

 ..do ...... ... .

 do 

Sorbitan monooleate..-. 

 do 

..... do ... 

..... do .

Polyoxyethylene sorbitan monooleate 

(Tween 80). 

__ do. ____ . ___

 do . -. 

..-.-do .. 

Polypropylene glycol 

monostearate.

 .do ... ... ... ..-- 

.. do .. 

_-__.do ... 

Tridecauol polyglycol 

ether sulfate, triethanolamine salt. 

 ..do .... ....... -

- do.. ......... ...

 do ..... -

Qlyceryl lacto-oleate 

(No. 6014).

.....do ..... .

 doSodium lauryl sulfate- . . 

----- do... ...... -

- do ... _

__ do .

Triethanolaminelauryl 

sulfate. 

.....do..... . 

 .do - .

 ..do..-. 

Monoethanolamine 

stearate.

 do ... _

Amount 

(grams)

2.5

5.0 

7.5

10.0 

2.5 

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0

2.5

5.0 

7.5 

10.0 

2.5

5.0 

7.5 

10.0 

4.2

5.0

Water 

(milliliters)

1,000

1,000 

1,000

1,000 

1,000 

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000 

1,000 

1,000 

1,000

1,000

Rennrks

Separated.

Do. 

Fair dispersion, some 

foam. 

Do. 

Separated. 

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do.

Excellent, stable dispersion; somewhat viscous 

for the field dispensers. 

Do. 

Do. 

Do. 

Do.

Do. 

Do. 

Do.

Stable dispersion, prepared to evaluate the 

effect of 3 percent hexadecanol on viscosity 

characteristics of the 

product. 

Stable dispersion, prepared to evaluate the 

effect of 3.5 percent 

hexadecanol on viscosity characteristics of 

the product.
52 EVAPORATION CONTROL RESEARCH, 1959-60

TABLE 4. Water-ir^oU dispersions of hexadecanol and octadecanol

Test

255... 

256 

257....

258 

261 

262 

263 

264...

265 

266 

267 

268 

269...

270 

271 

272 

273 

274 

275 

276 

277 

278 

279 

280 

281 

282... 

283. ..

Oil phase

Alkanol

Hexadecanol. 

 do _

 do 

__-_.do .

 do........

 do_ 

 __do __

 ..do -_-_

.-._. do -__

 do ....

- do _

 .do. ._

 .do _

Octadecanol 

..__.do ..-_

 __do __

 ..do 

 do 

-__..do ._..

-.-.do .

 do 

... ..do. .-.__._

_._..do __

 do _

.....do ____

Hexadecanol. 

 do ....

Amount 

(grams)

100 

100

100 

100

100

100 

100

100 

100 

100

100

100 

100 

100

100 

100

100 

100

100

100

100 

100

100 

100 

100 

180

100

Dispersing agent

Type

Sorbitan monostearate.

Sorbitan monolaurate.

Qlyceryl monostearate, selfemulsifying.

 ..do 

- .do... -------

.... .do 

.... .do .... ... 

Nonyl phenoxy polyoxyethylene condensate. 

Nonylphenpl-polyoxyethylene condensate.

Qlyceryl monostearate, selfemulsifying.

Sorbitan sesquioleate.-

Sodium-N-methylN-alkyl taurate. 

Alkyl phenol-polyoxyethylene condensation product. 

Ammonium alkyl 

sulfate.

Mono- and diglycerides of fatty acids 

plus preservative 

and antioxidant. 

N-coco- amino butyric 

acid. 

Qlyceryl lacto-oleate.. 

Polyoxyethylene sorbitan beeswax 

derivative. 

Polyoxyethylene 

stearate. 

Sorbitan monooleate. .

Sorbitan monostearate. 

Qlyceryl monostearate, selfemulsifying. 

Sorbitan sesquioleate 

. plus 10 gm cellulose 

gum.

Amount 

(grams)

10 

10

10 

10

10

10 

10

10 

10 

10

10

10 

10 

10

10 

10

10 

10

10

10

10 

10

10 

10 

10 

18

10

Water 

(milliliters)

100 

100

100 

100

200

300 

500

1,000 

1,000 

1,000

1,000

1,000 

1,000 

1,000

1,000 

1,000

1,000 

1,000

1,000

1,000

1,000 

1,000

1,000 

1,000 

1,000 

1,800

1,000

Spreading rate

Poor... 

-.do 

... do 

... do 

 do .

...doFair 

Good... 

Fair .

Good 

...doFair 

 do 

-_.do 

Fairly 

poor.

Fair . 

...doFair .

 do .

Fair -

Remarks

Stiff, heterogeneous 

pa^te. 

Stiff, heterogeneous 

pa^te, poorer than 

255. 

Past?; better texture 

ani appearance 

than 255 and 256. 

Past?, fairly good 

texture and 

appearance; better 

thin 257. 

Past?; not as stiff 

as 258. 

Pas1°; similar to 261. 

Thin paste; less 

viscous than 262. 

Liquid; similar to 

cream hand lotion. 

Thick, liquid dispersion. 

Separated quickly.

Goo'1 liquid dispersion. Separated somewhat 

afi er 24 hours 

standing. 

A rerun of 264.

Goo'1 dispersion; too 

vinous for current 

field dispensers. 

Good dispersion, but 

so'newaht gelatinous. 

StaT 'e dispersion. 

Thtok, spongy, 

stable dispersion. 

Separated.

Stal T e dispersion; 

soTie separation 

appeared imminent just after 

st'rring was 

stopped. Stable 

af «r 24 hours. 

See remarks, 274 

alove.

Separated.

Do. 

Do.

Do.

Thick, stable dispersion. 

Do.

Special preparation 

for preliminary 

field evaluation. 

Thick, spongy dispersion. Prepared 

to evaluate the 

"sponge" type 

formulation.
TABLES 53

TABLE 4. Water-in-oil dispersions of hexadecanol and octadecanol Continued

Test

284 

285 

305 

306 

307... 

308 

309 

Oil phase

Alkanol

Hexadecanol.

-. do... 

Octadecanol-

..... do. 

 do 

--..doAmount 

(grams)

100

100 

100

100 

100 

100 

100

Dispersing agent

Type

Sodium-N-methyl-Nalkyl plus 10 g 

cellulose gum.

 do .

N-cetyl-N-ethyl morpholinium ethosulfate. 

Polyoxyethylated 

fatty acid. 

Polyoxyethylated 

vegetable oil. 

Polyoxyethyl ated 

vegetable oil. 

Polyoxyethylated 

fatty alkanol.

Amount 

(grams)

10

10 

10

10 

10 

10 

10

Water 

(milliliters)

1,000

1,000 

1,000

1,000 

1,000 

1,000 

1,000

Spreading rate

 doFair.-. 

Fairly 

poor.

Fair 

Renarks

Thick, spongy dispersion. Prepared 

to evaliate the 

"spong?" type 

formulation. 

Do. 

Stable, but nearly 

solid dispersion.

Separated. 

Do. 

Do.

Stable, but very viscous dispersion. 

Would not flow 

througl dispensers.

TABLE 5. Dispersions containing 11 to 20 percent octadecanol (Lorol 28) "based 

on water, and using glyceryl monostearate (self-emulsifying) as the dispersing 

agent

Test

295 --------------

296 

297.. 

298 

299... . --------

300 

301 

302_ .. ._._.___

303_ 

304 

Octadecanol 

(Lorol 28) 

(grams)

110

120

130

140

150

160

170

180

190

200

Glyceryl 

monostearate 

(Arlacel 165) 

(grams)

11

12

13

14

15

16

17

18

19

20

Remarks

tory.

than 300.

TABLE 6. Dispersions of octadecanol containing varying amounts of glyceryl 

monosterate (self-emulsifying) as the dispersing agent

Test No.

286_ ____________________________

287. ____________________________

288_ ____________________________

289_ . _. _

290_ ____________________________

291 ______...._.__._.___.._____._

Glyceryl monostearate (Arlacel 165) 

(grams)

10

11

12

13

14

15

Remark?

Stable, foamy.

Do.

Stable.

Do.

Do.

Do.,
INDEX

Page

Alkanol, coacervation... __ 13

methods of applying...,. __ 5,6

orientation... . __ 4

solid, dispensing- .. 22,23

field tests .. -.._..___ 23,38

mixing method. ....______ 22

spreading characteristics.. ____ 22

spreading characteristics.-.-- ..____ 9-10

suggestions for future work - _______ 41

See also under individual alkanol.

Biological effects of tests ..______.. 20,

21,22,24,27,28,30,33,36,38

Briones stock pond, tests at......______ 17-22

Carlos stock tank, tests at__________ 28-33 

Coacervation__________________ 12,13

Dispensers, aerosol-type.. .________ 18-20 

continuous drip-type... ___ 22-24 

gravity-type.. . 20,21 

wind-controlled. ___ 24,25,26,29,34

Dodecanol, field tests. ...__ 20-21,37 

in water-in-oil emulsions__._____ 46 

spreading characteristics __ 20,21

Emulsiflers, available_____________ 45-46

Energy, contributed to storage________ 32

lost by conduction and radiation...___ 31

utilized by evaporation . ..___ 31-32

Essar Ranch Lake, tests at. ________ 33-36

Evaporation, factor in test evaluation____ 16

film resistance to, theoretical-...____ 3-5

reduction, computation.-________ 32-33

Field studies, methods of evaluation...___ 15-17 

results- .. ...___ 37-39 

sites of tests. _______________ 14-15 

suggestions for future work... ___ 40-41 

tests_________.__________ 17-36

Film, extent of coverage.. -- ____ 17 

field tests.._______.-.._______ 17-36 

resistance to evaporation, theoretical__ 3-5 

theory of spreading. _________ 3,5 

thickness..-_____.._________ 4,5

Floating barrier-..... ... _ _ 27-28

Future work, effect of impurities_ _____ 39-40 

effect of increase in surface temperature_ 41 

effect of relative humidity. _______. 40

Page

Future work, effect of impurities Continued

effect of the wind____-___ 40 

polymorphism of long chain alkano?s..... 40 

reflective solar cover_ .. 41 

use of docosanol and eicosanol . -- 40

Hexadecanol, collapse of film. 30 

field tests.. . 17-20,24-27,30,37 

reaction to heat .- 26 

spreading characteristics 19

Hydrophile-Lipophile Balance .. 13,14,46

Laboratory studies, application to fiell conditions.___ ... - 5-6 

conclusions__.. 13-14 

experimental..____ 6-13 

suggestions for future work.... 39-40 

theoretical considerations 3-5

Octadecanol, field tests. -.. - 22-24,2"-30,33-36,37 

reaction to heat____ 30-31

spreading characteristics 

withglyceryl monostearate .. . 

Oil-in-water dispersion, application to reservoir___ 

orientation of molecules - 

...... 12

 7

photomicrographs- 11 

preparation..______ 8,9,46-51

Pinta stock tank, tests at.. ------- - 24-28

Purpose and scope of investigation 2

Temperature of water surface, factor in test

evaluation- 15 

Theory of spreading.... 3,5 

Toxicity of dispersing agents- 6,14,38 

Trade names of emulsifiers-- - 45-46

Vapor pressure of the air, factor in test evaluation 16

Water-in-oil dispersion, cooling methods.- 10 

orientation of molecules 7 

photomicrographs_... . 11 

preparation... .___. 6,8-10,52-53

Wind speed, factor in test evaluation 15

Zimmerman stock tank, tests at...-. 22-24

55

U. S. GOVERNMENT PRINTING OFFICE : 1963 O - 649816