*)TH CONGRESS, } HOUSE OF REPRESENTATIVES. ( DOCUMENT

2d Session. \ j No. 74.

Water-Supply and Irrigation Paper No. 189 Series L, Quality of Water, 17 

DEPAETMENT OF THE INTERIOR

UNITED STATES GEOLOGICAL SURVEY

CHARLES IX WALCOTT, DIRECTOR

THE PREVENTION OF STREAM POLLUTION 

^ BY STRAWBOARD WASTE

U, S. GEOLOGICAL SURVEY, 

BOX 138, 

ROLLA, MO.

EARLE BERNARD PHELPS

IN COOPERATION WITH THE SANITARY RESEARCH LABOR >TORY AND SEWAGE

EXPERIMENT STATION OF THE MASSACHUSETTS

INSTITUTE OF TECHNOLOGY

WASHINGTON

GOVERNMENT PRINTING OFFICE

1906

CONTENTS.

Page.

Introduction............................................................. 5

The manufacture of strawboard .----.....__..___.__..._..........---.-..-. 6

Steaming in rotaries ....-....-.......___.............................- 6

Washing........................................ .................... 7

Drying ............................................................. 7

The disposal of waste liquor.-.............................................. 8

Method in use... ........--....'--........___,.._........-.......-...- 8

Proposed methods.................................................... 9

Centrifugal separation ............................................ 9

Precipitation with carbon dioxide ................................. 9

Laboratory investigations ................................................. 10

Chemical stud}' of the soluble matter .................................. 10

Precipitation experiments............................................. 10

Sedimentation experiments ........................................... 12

Summary ............................................................. 12

Field investigations-....................................................... 13

Acknowledgments.................................................... 13

Amount of water used ................................................ 13

Raw material and finished product .................................... 15

Character of the machine water ....................................... 16

Mechanical filtration ................................................. 16

Description of the filter........................................... 16

Preliminary sedimentation........................................ 19

Amount of wash water............................................ ' 20

Disposal of wash water............................................. 21

Character of effluent............ .................................. 21

The sludge....................................................... 24

Amount and composition ..................................... 24

Properties and uses........................................... 25

Resume of method of treatment................... ............... 26

Character of waste water after treatment........................... 27

Cost of the process ............................................... 28

Summary................................................................ 29

Index ................................................................... 31

ILLUSTRATIONS.

Page. 

PLATE I. A, View of strawboard mill; B, Piles of baled straw .............. 6

II. A, Sedimentation tanks and float regulator; B, Experimental filter,

sedimentation tanks, and measuring tank ...................... 18

FIG. 1. Details of experimental filter....................................... 17

2. Sectional view of standard orifice................................... 18
r
THE PREVENTION OF STREAM POLLUTION BY 

STRAWBOARD WASTE."

By EARLE BERNARD PHELPS.

INTRODUCTION.

The disposal of the waste liquors resulting from the manufacture of 

strawboard forms one of the most important problems connected with 

the prevention of stream pollution. In 1900 the total production of 

strawboard in the United States was 157,534 tons at 59 factories. 

For each ton of strawboard manufactured there were discharged into 

the streams about 65,000 gallons of waste liquor that contained 1,173 

pounds of straw and mineral matter and 490 pounds of lime. The total 

waste discharged into the streams in 1900 amounted to 10,239,710,000 

gallons of liquor, containing 184,777,382 pounds of straw and mineral 

matter and 77,191.660 pounds of lime. This enormous waste was 

discharged by 59 plants of various sizes, but as most of these mills are 

along small streams the resulting pollution is very apparent. Some 

idea of the amount of this pollution may be obtained from PI. I, B, 

The baled straw shown is a three months' supply for a mill having an 

output of 30 tons a day. In three months one third of this straw will 

be discharged into the stream as waste matter.

The problem of the disposal of the waste water has been studied by 

Prof. R. L. Sackett, of Earlham College, 6 and the present investigation is a continuation of the work of Sackett along new lines. In 

approaching the problem it is necessary to keep constantly in mind 

the economic conditions affecting the industry. The low selling price 

of the product, the immense volume of waste water necessary, and the 

fact that competition between strawboard and other forms of cheap 

board is active, make it quite impracticable for the manufacturers to

"This investigation was made in cooperation with the Sanitary Research Laboratory and Sewage 

Experiment Station of the Massachusetts Institute of Technology. 

6 Water-Sup, and Irr. Paper No. 113, U. S. Geol. Survey, 1905, pp. »-35.

5
6 STREAM POLLUTION BY STRAWBOARD WASTE.

adopt any process involving serious expenditures. The solution of the 

problem must be sought in a process which will show an actual saving. 

Aside from the matter of the recovery of by-products of commercial 

value, this means that the process must compete in cost with the 

present unsatisfactory sedimentation methods employed at many of the 

mills, to the cost of which may reasonably be added the almost constant 

expense of lawsuits and injunction proceedings, the latter in some 

cases causing the closing of the mill.

As a result of this study it has been found that sedimentation of the 

waste water for a short period, followed by filtration thru sand at 

high rates the so-called mechanical filtration, but without coagulants will produce an effluent from which more than 90 per cent of 

the suspended organic matter has been removed. This effluent, while 

not ideal, is probably purified to such an extent that, allowing a factor 

of safety of 2 for impurities in the stream, it may be discharged into 

streams having a minimum flow of twice the discharge of the mill 

without producing a nuisance. The cost of filtration by this process, 

after the initial cost of installation, is practically reduced to the 

cost of pumping the wash water. The final result is a heav}7 sludge, 

whose volume is less than 5 per cent of the initial volume of the waste. 

Ultimate disposal of this sludge could be made either by discharge 

over land for spontaneous evaporation, by evaporation by means of 

artificial heat, or by filter pressing. The sludge has some value as a 

fertilizer, and there are also certain commercial uses to which it seems 

to be adapted.

THE MANUFACTURE OF STRAWBOARD.

The following description of the manufacture of strawboard is taken 

from Professor Sackett's paper : a

STEAMING IN EOTAEJES.

The straw is first subjected to a cooking process by steam and lime. A-large 

ellipsoidal rotating steel boiler called a '' rotary" * * * is filled with straw, 

which is then cooked down with steam, then again filled and cooked down until the 

rotary boiler has been completely filled. The process of filling a rotary occupies 

from six to twelve hours. The final charge consists of about 6 tons of straw and 30 

bushels, or 2,100 pounds, of lime in the form of milk. This mixture is then rotated 

and cooked under 40 pounds of steam pressure for twelve hours. * * * This 

apparently severe chemical and mechanical action results in a rapid softening of the 

woody fiber and in the reduction of the straw to a dark-yellow, pulpy mass. This 

"stock," as it is called, is stacked in piles 10 to 15 feet high to drain. Concerning 

the action which takes place in the rotaries, the Journal of the Society of Chemical 

Industry says: &

"The chemical action of the milk of lime on the incrusting materials surrounding 

the straw fiber is not a vigorous one. These incrusting materials are not completely,

a Water-Sup, and Irr. Paper No. 113, U. S. Geol. Survey, 1905, pp. 13-15. 

b For February 28, 1894, p. 101.
U. S. GEOLOGIi XL SURVEY WATER-SUPPLY PAPER NO. 189 PL.

A. VIEW OF STRAWBOARD MILL.

B. PILES OF BALED HAY. 

One-third, by weight, will be wasted in three months.

THE MANUFACTURE OF STRAWBOARD. 7

nor, indeed, to a great extent, separated from the cellulose. The mineral matter 

remains in the .product.practically untouched, and if any less quantity than that 

corresponding to the percentage in the original straw operated upon exists in the 

prepared pulp, it is due rather to the washing after digestion than to any solvent 

action of the milk of lime. Milk of lime under certain conditions has a bleaching 

action upon the straw. It neutralizes the organic acids usually found when fibrous 

plants are heated for any length of time in the presence of water."

The yield of pulp at this point will be from 75 to 80 per cent of the weight of the 

original material. * * *

The material is allowed to stand in these piles for twenty-four hours or more to 

drain. After it is thus drained it contains about 50 per cent of water and from 6 to 

7 per cent of lime. This is equivalent to from 12 to 14 per cent of lime in the dry 

straw. Since the original charge of lime and straw was in the proportion of 2,100 

pounds of lime to 14,100 pounds of straw and lime, or about 14 per cent lime, practically none of the latter has drained out with the condensed steam. This drainage 

from the stock piles forms but a small part of the waste sewage. It is straw colored 

and very turbid, carrying a small quantity of fiber broken fine in the rotaries.

WASHING.

This process is much more drastic, and it is here that the great volume of waste is 

produced.

The stock is run thru washing machines for the purpose of removing the lime. 

* * * The washing machine consists of an oval channel about 3 feet wide, around 

which the stock travels, being supplied with copious volumes of water. Across this 

channel is 'placed a cylinder, 42 inches in diameter and 42 inches long, having longitudinal ribs or flanges about three-fourths of an inch 'square in section and threefourths of an inch apart. Meshing with this, like the teeth of geared wheels, is an 

idler, below, of similar size and form. These wheels, revolving, lift the water and 

straw to a level several inches higher than that in the oval channel, whence it flows 

by gravity halfway around its course to a point where it meets a revolving brass 

screen of fine mesh, thru which a part of the water escapes, carrying with it the finer 

particles of fiber and free lime. The remaining straw, with additional volumes of 

fresh water, now passes many times thru the rolls, which further mash and break the 

fiber, and around to the screen, where more straw, lime, and water escape. * * *

After the washing process the straw, with a considerable volume of water, is led to 

a train of rolls, consisting of three parts first, the wet end; second, the hot rolls; 

third, the trimming and cutting machine. As it comes from the washers the material is run into vats, where it is mixt with large quantities of water and past over 

hollow cylinders having fine wire-cloth faces, which allow the water to escape, leaving the fiber on the surface of the cylinder. The fiber is then taken by woolen felts, 

which are prest down on the surface of the cylinder. This makes a web of paper 

on the felt. The pulp, which is now about one-third straw and two-thirds water, 

travels up and down, over and under a double train of hot rolls, heated by steam 

that is carried in thru hollow bearings. As the pulp passes on thru the train it is 

constantly prest and dried, until finally it is separated from its cloth support and 

goes to the trimming machine, where it is cut into sheets of proper size. It now 

contains about 10 per cent of water and a small quantity of lime. The board is 

manufactured in many thicknesses and weights. Just before it is trimmed it may be 

coated on one or both sides with a thin paper facing or finish.
8 STREAM POLLUTION BY STEAWBOAED WASTE.

THE DISPOSAL OF WASTE LIQUOR. 

METHOD IN USE.

At present, so far as can be learned, the only method of treating the 

waste liquor in actual use by the manufacturers is that of prolonged 

sedimentation in open fields. The overflow water from these fields is 

not satisfactorily clarified at all times of the year. During cold 

weather it is fairly clear and can be discharged without serious harm. 

During the summer, however, a very offensive fermentation takes 

place in the accumulated sludge, giving rise to objectionable odors and 

blackening the water. At such times the aim is to hold all the waste 

water in the ponds, trusting to evaporation and to the storage capacity of 

the ponds until cold weather again relieves the situation and the increased 

flow of the stream permits a discharge of the surplus water stored. 

The most serious objection to this process, which seems to be satisfactory to riparian owners below, is the fact that these ponds are continually filling up with a soft mud, which destroys their function as sedimentation basins and renders them useless for other purposes. The 

time must come, even in the most favorable situation, when additional 

land can not be afforded for this purpose. A second objection is that 

the accumulated sludge is held for years and slowly putrefies. The 

organic matter of the waste is but slightly nitrogenous and is fairly 

stable. It probably contains some reducing sugars capable of rapid 

fermentation if kept in concentrated form and if given at the same 

time some nitrogenous matter. The slow decomposition of the stable 

straw material supplies the necessary nitrogen, and the result is a very 

rapid multiplication of the putrefactive organisms and an accompanying offensive putrefaction. Laboratory experiments have shown that 

the soluble sugars by themselves, as found in a filtered sample of the 

waste water, do not ferment or decompose, and that even the unfiltered 

waste is not subject to a quick putrefaction such as characterizes sewage matter. In fact, bottles have been stored for over a year without 

any evidence of fermentation, and it may very reasonably be held that 

the necessary nitrogen comes largely from the bottom of the ponds, 

rather than from the sludge itself. Inspection of the stream below 

one of these ponds showed that, while putrefaction was barely noticeable and not at all offensive in the pond itself, the admixture of some 

of this water with that of a small brook, highly polluted with the refuse of a slaughterhouse, had immediately a very offensive result. 

Investigation of the condition of the streams below these mills reveals 

the fact that the most serious nuisance generally occurs at a point very 

remote from the mill itself. It is directly caused by the slow decomposition of material deposited in the bed of the stream. The conditions are doubtless aggravated by the simultaneous precipitation of
THE DISPOSAL OP WASTE LIQUOE. 9

other polluting substances, notably sewage, brought about by the free 

lime of the strawboard waste.

The effective solution of the problem lies in the rapid separation of 

the solid matter from the dissolved sugars and lime and a subsequent 

dilution of the latter so that they shall be innocuous. The insoluble 

material when dry is entirely stable. The present system, therefore, 

is not onty unsatisfactory from the economic side, but it works on 

a wrong principle for satisfactory purification in that it encourages 

putrefaction.

The cost of these ponds at four of the larger mills of the United 

Box-board and Paper Company, as stated by an official of that company, has been, in round numbers, to date, $10,000, $15,000, $18,000, 

and $8,000. In the last case the results were still unsatisfactory, and 

after a considerable expenditure on other experiments the company 

has been obliged, to close this mill.

PROPOSED METHODS.

CENTRIFUGAL SEPARATION.

Centrifugal separation of the solid matter from the liquor was tried 

at Tiffin, Ohio, in 1904. It has not been possible to obtain more definite information concerning those experiments than ia'contained in the 

trade papers of that time. It is understood, however, that the results 

were quite satisfactory, but that the cost of operation was prohibitive. 

The account referred to (see Paper Trade Journal, February 2, 1905) 

states that the effluent was clear and colorless and that the residue was 

found by analysis to be valuable as a fertilizer.

PRECIPITATION WITH CARBON DIOXIDE.

As a result of his investigations Sackett concluded that plain sedimentation would remove about 10 per cent of the suspended solids in 

twenty-four hours and that during the ensuing twenty-four hours 'the 

additional removal was very slight; that good purification could be 

effected by chemical precipitation only by using sulfate of aluminum 

in excessive amounts and at an entirely prohibitive cost; that sulfate 

of iron gave inferior and unsatisfactory results, and, finally, that by a 

process of precipitation with carbon dioxide and lime an average 

removal of 85 per cent of the suspended matter could be effected.

The process recommended by Sackett consists in (a) saturation of 

the waste water with carbon dioxide to form bicarbonate with all the 

lime present; (£) addition of lime equal to that already present to form 

a normal carbonate; (c) sedimentation of the precipitated carbonate 

and consequent dragging down of some of the organic matter, and (d) 

filtration of the resulting clarified liquor thru sand at rates of 500,000 

to 2,000,000 gallons per acre per day. This process has never been used 

by manufacturers so far as the writer is aware.
10 STREAM POLLUTION BY STRAWBOAKD WASTE.

It does not appear from SackettV report that he tried the simpler 

but equivalent process of saturating one-half the total volume with 

carbon dioxide and then mixing with the other half. Such treatment 

would doubtless have precipitated the calcium fully as well, with a 

saving of one-half the carbon dioxide and all the lime required by the 

process recommended. An examination of the analytical data shows 

that the removal of suspended organic matter accomplished by the 

precipitation and sedimentation processes varied from zero to 75 per 

cent, with a mean value of 37 per cent. Experiments on plain sedimentation, made by the writer both in the laboratory and on a large 

scale in the field, show it to be equally efficient for the removal of suspended organic matter. The fact is that the precipitated carbonate of 

calcium is very finely divided and has no value as a coagulant. The 

process is valuable to remove the lime, if that be desirable. It 

hardly seems, however, that the value of discharging a lime-free 

effluent into the hard waters of the Middle West is at all commensurate 

with the cost of treatment.

LABORATORY INVESTIGATIONS. 

CHEMICAL STUDT OF THE SOLUBLE MATTER.

Several barrels of the strawboard waste liquor were shipped to Boston from one of the mills of the United Box-board and Paper Company, 

and on this material a series of investigations was carried out. Sackett's experiments with various coagulants were repeated and his results 

confirmed. It was found that the poor results obtained with any but 

excessive amounts of iron or aluminum sulfate were due to the presence of a substance in solution which forms soluble combinations with 

those metals. This substance was isolated by precipitation with hydrochloric acid, and after repeated purification was found to have the 

following properties: It is an organic acid, probably related to the 

humic or ulmic acids of the soil and peaty waters. It exists in the 

waste water as a calcium salt, having partially neutralized the free 

lime used in the digestion. It is precipitated by strong acids, coming 

out as a dark-red substance which turns brown on slow oxidation in 

the air. It can be redissolved in a solution of sodium carbonate, 

giving a garnet-red solution. It dissolves in alcohol, giving a deepred color, but oxidizes to a brown insoluble substance. Its calcium 

and aluminum salts are not soluble when prepared from the insoluble 

acid, but the acid can not be precipitated from its solutions by these 

metals. It appears that there are formed colloidal suspensions of the 

calcium and aluminum salts. The solutions have a bright-yellow color 

and colloidal appearance. The iron compound is similar but of a green 

color. The sodium salt appears to be soluble and to dissociate into 

deeply colored acid ions.
LABOEATOEY INVESTIGATIONS. 11

A second substance isolated from the waste has the following properties: It is soluble in water and not precipitated by any of the 

common precipitants, including alum, ferrous sulfate, lead acetate 

(normal or basic), carbonates, hydrates, or acids. It is responsible 

for a large part of the color of the water and can not be removed by 

any practical method.

These two substances with the lime make up the greater part of the 

dissolved material. They are entirely stable and do not undergo putrefactive change when stored in the incubator, either alone or mixt with 

varying proportions of tap water. In addition to these substances 

small amounts of reducible sugars are present. The amount is so 

small that in any material dilution of the liquor the dilution of these 

sugars will prevent their manifesting themselves as putrefactive agents. 

These sugars are probably responsible for the slow fermentation in 

the sedimentation fields after the lime has been sufficiently removed 

to allow the action to proceed.

PRECIPITATION EXPERIMENTS.

Substances in suspension may be removed by filtration or by sedimentation. When the material is finely divided or of low specific 

gravity, either process may sometimes be assisted by the application 

of suitable coagulants. These tend to clot the small particles into 

larger flakes, and by their own greater density carry the clotted 

material to the bottom. Two chemical substances are required, as a 

rule, to produce the necessary precipitation, one of which is generally 

the calcium bicarbonate found normally in the water. This calcium 

salt reacts with the sulfates of certain metals, notably iron or aluminum, to produce the sulfate of calcium and the hydrates of the corresponding metals. In the present case there is a large amount of free 

lime in solution. It would seem, therefore, that precipitation might 

be brought about by the addition of either copperas or alum. Experiments showed that copperas failed to react at all and that fair results 

could be obtained with alum, but only at a prohibitive cost. As will 

be seen in the accompanying tables of results, the removal of organic 

matter by alum was much better than that obtained by plain sedimentation.

Results of precipitation experiment on strawboard waste.

Sample.

Waste after 2 hours' i-enitnentation:

Suspended solids.

Present.

Parts per 

million. 

1,350

120 

560

Removed.

Per cent.

91 

59

« The coagulant used was alum in the proportion of 10 grains of sulfate of aluminum per gallon.
12 . STEEAM POLLUTION BY STKAWBOAED WASTE.

Increasing the amount of aluminum sulfate gave practically the 

same result. Smaller amounts gave indeiinite and at times negative 

results. The use of 10 grains per gallon of sulfate of aluminum at 1 

cent a pound would represent a cost of about 43 cents per ton of finished product of the mill. The studies on the nature of the dissolved 

material already referred to explain these poor precipitation results 

with alum. Soluble compounds are formed with the organic acid, 

instead of aluminum hydrate, the desired coagulant.

Experiments were made with carbon dioxide according to Sackett's 

procedure, and his results were confirmed. There was but a slight 

removal of suspended organic matter about 30 percent which could 

be produced equally well by plain sedimentatiqn. In fact, under 

actual working conditions sedimentation was found to be even more 

effective.

SEDIMENTATION EXPERIMENTS.

In a study of plain sedimentation it is important to know the rate 

of sedimentation and how this varies with the time. With satisfactory data on this point it is possible to estimate the amount of clarification which may be expected to result from any given period of 

sedimentation and to establish the most suitable period for the case in 

hand. It was observed early in this work that apparently a large 

portion of the suspended solids settled out in a very short time, and 

that to all appearances further improvement was extremely slow. 

The determinations of the total solids given in the following table 

show that there is no practical advantage in sedimentation for a period 

of much over one hour:

Effect of sedimentation on strawboard waste.

Suspended solids.

Present.

Parts per 

million. 

..................... 1,344

..................... 548

..................... 494

Removed.

Per cent.

59

63

SUMMARY.

As a summary of the laboratory investigations, it may be said that 

the removal of the dissolved coloring and other organic matter and 

the lime in an economical way is impractical; that by plain sedimentation a removal of suspended material practically as good as the best 

removal observed with the use of a coagulant can be accomplished; 

and that a sedimentation period of one hour is sufficient for the 

removal of about 60 per cent of the suspended solids, a longer period 

increasing this removal but slightly. For the removal of the remainder of the suspended matter, there remains but one process filtration. 

It was therefore decided to make an actual field test of this method of
FIELD INVESTIGATIONS. 13

purification. The very large amounts of suspended matter to be handled seemed to eliminate at the outset the possible use of slow sand 

filtration, so that it was obvious that mechanical filtration at high rates 

and with some provision for removing the accumulated sludge from 

the surface of the filters was the only system applicable to the problem.

FIELD INVESTIGATIONS. 

ACKNOWLEDGMENTS.

In March and April, 1905, a visit was made to one of the mills of 

the United Box-board and Paper Company, at Urbana, Ohio. Every 

opportunity was given the writer to make a thoro study of the processes of manufacture, and it is here desired to make suitable 

acknowledgments to Mr. Rush E. Evans, division manager, and to 

Mr. D. C. Amerine, superintendent, for the many courtesies extended, 

both on that occasion and during the subsequent visit for the installation of an experimental plant.

AMOUNT OF WATER USED.

It was found that conditions were favorable for measuring the 

entire volume of waste water, as it left the mill in a waste flume. As 

a cheek on these measurements, observations of the rate of operation 

of the pump were made, all the water used being pumped from a large 

well under the mill.

A rectangular flume, whose mean width was 1.96 feet, was used for 

these measurements. A distance of 100 feet was measured off in a 

portion where the slope was practically constant. To determine the 

velocity of flow at various elevations in the flume, a float was used 

which was nearly as long as the width of the flume and way provided 

with vanes underneath, so that it always floated squarely across the 

flume. The following observations are the mean of a large number 

made at various elevations of water in the flume:

Mean depth, velocity, and flow of waste water in flume of mill of United Box-board and 

Paper Company, Urbana, Ohio.

Depth of 

water.

Foot.

0.19

.25

.29

.31

.33

.37

Velocity 

of flow.

Feet per

second.

3.1

3.8

4.0

4.2

4.3

4.5

Area of 

cross section.

Square foot.

0.37

.49

.57

.61

.65

.72

Flow.

Cubicfeet

per second.

1.1

1.9

2.3

2.6

2.8 .

3.2

These values of the depth arid the corresponding flow were then 

plotted. The most probable line was drawn thru them, and that curve 

was used as the true rating curve of the flume in the subsequent 

calculations.
14 STREAM POLLUTION BY STRAWBOARD WASTE.

During the two hours from 10.45 a. m. to 12.45 p. m., March 30, a 

test run was made to determine the total flow. The following readings 

of the elevation of the water in the waste flume were made, and from 

these readings has been calculated the total flow for the two hours:

Flow of waste ivater in flume of mill of United Box-board and Paper Company, Urbana,

Ohio, March 30, 1905.

Time.

1 1 ^n « m

12.30p.m...............................................

Total. .............................................

Depth.

Foot. 

0.29 

.29 

.33 

.33 

.33 

.33 

.38 

36

.33

Plow.

Cubic feet 

per second. 

2.3 

2.3 

2.8 

2.8 

2.8 

2.8 

3.4 

3.1 

2.8

Flow for 15-minute 

period.

Mean rate 

of flow.

Cubicfeet 

per second.

2.3 

2.6 

'2.8 

2.8 

2.8 

3.1 

3.2 

3.0

Total flow.

CiMcfeet.

2,100 

2,300 

2,500 

2,500 

2,500 

2,800 

3,000 

2,700

20,400

This total flow of 20,400 cubic feet in two hours represents an 

average flow of 2.69 cubic feet per second.

A few measurements were made of the water running in the waste 

flume when the beaters were not running and again when the paper 

machine was stopt. The flow from the machine was found to be 

fairly constant at 1.4 cubic feet per second, and the beaters were 

found to discharge amounts of 1.2 to 1.8 cubic feet per second, 

depending on the number of beaters in operation at the time.

During the test run observations of the rate of operation of the 

pump were made at short intervals. The purnp was a double-acting 

duplex Smith-Vaile pump, with water cjdinders 14 inches in diameter 

and with a stroke of 15 inches. Slip being neglected, the capacity of 

the pump is, therefore, 1.335 cubic feet per stroke, or 5.340 cubic feet 

per complete revolution. Following are the observations made on the 

pump and the calculated rate of pumping:

Discharge of pump at mill of United Box-board and Paper Company, Urbana, Ohio,

March SO, 1905.

Time.

Do......................................

12.45 p. m ...................................

Revolutions per 

minute.

31 

30 

30 

30 

30 

30 

a 40 

40 

38

Discharge.

Cubic feet 

per second. 

2.28 

2.67 

2.67 

2.67 

2.67 

2.67 

3.58 

3.58 

3.57

Time between observations.

Seconds. 

0 

900 

900 

900 

900 

600

1,800 

1,200

Discharge of pump between observations.

Mean.

Cubicfeet 

per second.

2.43 

2.67 

2.67 

2.67 

2.67

3.58 

3.48

Total.

Cubicfeet.

2,457 

2,403 

2,403 

2,403 

1,602

6,444 

4.176

21,888

a Changed.
FIELD INVESTIGATIONS. 15

During the test four of the seven rotaries were filled. Two hundred 

and fi'fty cubic feet of water are required for each rotary, or 1,750 

cubic feet for the seven.^ Since all seven are filled only once in twenty - 

four hours the water used in this process amounts to 73 cubic feet per 

hour for the whole day. The water so used during the two hours of 

the test was, however, 750 cubic feet, an excess of 604 cubic feet over 

the normal mean consumption. The amount pumped must, therefore, 

be corrected by this amount. The elevation of the water in the supply 

tank was 1 foot greater at the end of the test than at the start. The 

diameter of the tank is 12 feet. This storage amounts, therefore, to 

113 cubic feet, and must also be applied as a correction. A small 

stream of water was being wasted from the engine condenser. This 

stream was roughly estimated by float measurements to be about 0.3 

cubic foot per second, or 2,160 cubic feet during the two hours of the 

run. These three corrections amount to 2,888 cubic feet, which is to 

be subtracted from the total pumped, 21,888 cubic feet, leaving a net 

pumpage of 19,000 cubic feet for two hours, or 2.64 cubic feet per 

second, a result,in close agreement with the 2.69 cubic feet per second 

measured in the waste flume.

RAW MATERIAL AND FINISHED PRODUCT.

During this test run, careful weighings were made of the amount of 

finished board produced. The figures were as follows: .

Product of mill of United Box-board and Paper Company, Urbana, Ohio, for two hours,

March 30, 1905.

Pounds. 

Gross product................................................ 4,841

Waste and trimmings......................................... 196

Net product............................................ 4,645

Dividing the total amount of waste liquor, 20,400 cubic feet, by the 

amount of net product gives.8.780 cubic feet, or, roughly, 65,000 gallons per ton of product. As the daily product of this mill is about 30 

tons, about 1,900,000 gallons of waste water are discharged each day.

The charge of one rotary was carefully weighed. There were used 

133 bales of straw, of an average weight of 102 pounds, or a total of 

13,600 pounds of straw. The amount of lime was weighed, but the 

weight was somewhat in excess of the average amount used, as determined by the total weekly consumption of lime. The latter figure, 

which is 2,100 pounds per charge, will therefore be used. The total 

amount of straw used in the 7 rotaries is accordingly 95,200 pounds 

per day, and of lime, 14,700 pounds per day. Subtracting from this 

the 60,000 pounds of finished product leaves a waste of 35,200 pounds 

of vegetable and mineral matter from the straw and 14,700 pounds of 

lime, which is carried off each day in the 1.9 million gallons of water.
16 STEEAM POLLUTION BY STKAWBOAKD WASTE.

Calculated into parts per million, these figures give about 2,400 parts 

of straw material and about 1,000 parts of lime. Analyses of average 

samples of the waste water gave about 600 parts of calcium or 840 

parts of lime per million. The difference is due partly to the loss of 

lime during the draining of the digested pulp and largely to impurity 

of the lime.

CHARACTER OF THE MACHINE WATER.

Determinations of the lime were made on the well water and on the 

various waste waters. It was found that the greater part of the lime 

is washt out in the beaters and that the water from the machine contained but little lime in excess of that in the raw water. The actual 

figures were:

Calcium in ivaste water.

[Parts per million.]

Well water .................................................. 238

Beater water................................................. 1,164

Machine water. .......................... .................. 380

A rough determination of the impurities was made by precipitating 

the lime and organic matter, with a large excess of alum. A 6-inch 

column of the beater water gave a layer of precipitate an inch thick, 

while the amount obtained from the machine water was too small to 

be measured.

MECHANICAL FILTRATION.

In May, 1906, a small experimental filter was installed at this mill, 

in order to obtain some practical data on the efficiency of treating the 

waste by mechanical filtration. The filter and accessories were loaned 

by the New York Continental Jewell Filtration Company, of New 

York, thru the courtesy of Mr. E. E. Milligan, assistant general 

manager, and the expenses of shipment and installation were borne by 

the paper company.

DESCRIPTION OP THE FILTER.

The filter used is shown in fig. 1. The waste water, after passing 

the regulating butterfly valve, divided into two streams and entered 

the bottoms of the two sedimentation tanks. These tanks were of 

cypress, each having a diameter of 4 feet and a depth to the overflow 

line of 3.2 feet. The capacity of the two was 603 gallons. The 

water was delivered to the tanks thru half-inch holes in the sides of 

risers extending to the surface. The vertical distribution was, therefore, very uniform. Vertical baffles caused the water to flow completely thru the tanks, and a funnel-shaped overflow collected the 

clarified water from the surface of each tank and delivered it to the 

surface of the filter. The filter proper was of galvanized iron, set
MECHANICAL FILTEATION. 17

upon a cast-iron base, provided with a false bottom of fine brass 

screening. The diameter of the filter was 20 inches, and its total 

depth to the false bottom was 5 feet. Suitable connections and valves

FIG. 1. Details of experimental filter.

were provided, as shown in the drawing, so that the influent and the 

effluent water could be cut off, a stream of wash water could be

IRK 189 06 2
18 STREAM POLLUTION BY STRAWBOARD WASTE.

admitted from the bottom, and the dirty wash water, overflowing 

from the top, could either be wasted thru the sewer connection or 

returned to the sedimentation tanks. The device for stirring the 

sand during washing was operated by hand. Wash water was supplied from an elevated tank under such a head that a maximum flow 

of 25 gallons per minute, or 12 gallons per square foot per minute, 

was possible. A flow of about 8 gallons v per square foot per minute 

was generally used. Suitable connections were also made between 

the bottoms of the sedimentation tanks and the sewer. A 50-gallon 

barrel at the end of the sewer line served as a measuring tank for the 

wash water or the sludge. The rate of flow thru the filter was regulated at the outlet by a standard orifice, a sectional view of which is 

shown in fig. 2. The orifice itself wus a trifle over seven-sixteenths

3 inches

FIG. 2. Sectional view of standard orifice.

of an inch in diameter. The brass cap containing the orifice was 

screwed over a nipple of 1-inch pipe, which was in turn connected 

with a 2-inch tee. The opposite side of this tee was connected by a 

short pipe to the valve regulating the outflow, and a glass tube, fitted 

to the upper opening of the tee, permitted the static head on the 

orifice to be read at any time. The large sectional area of the tee as 

compared with that of the orifice reduced the velocity of approach to 

a negligible value. This device was roughly calibrated in the field and 

was subsequently carefully calibrated by discharging into a large 

measuring tank. The rough field values were found to be substantially correct.
U. S. GEOLOGICAL SURVEY

A SEDIMENTATION TANKS AND FLOAT REGULATOR,

WATER-SUPPLY PAPER NO. 189 PL. II

K. EXPERIMENTAL FILTER, SEDIMENTATION TANKS, AND 

MEASURING TANK,

MECHANICAL FILTRATION. 19

The rate of inflow to the tanks was adjusted to the rate of filtration 

by the butterfly valve, actuated by a float in one of the tanks (not 

shown). The filter was filled tp a depth of 3 feet with clean 16-30 

beach sand, i. e., sand which will all pass a screen with 16 meshes to 

the linear inch and be retained on a screen with 30 meshes. The water 

line was 18 inches above the surface of the sand.

The appearance of the filter and sedimentation tanks as they were 

set up is well shown in PL II. PI. II, A, shows the sedimentation 

tanks, the influent pipe and controlling valves, and the lever arm of 

the float operating the butterfly valve. PI. II, B, shows the filter 

itself, the loss-of-head gage, and the connections with the tanks and 

the sewer. To the extreme right is the measuring tank, and passing 

between the two tanks on the ground the wash-water pipe line can be 

seen. The outlet of the filter is hidden from view behind the mound 

of earth in the foreground.

PRELIMINARY SEDIMENTATION.

A number of tests were first made to determine the rate of change 

in the loss of head during filtration with varying periods of preliminary sedimentation. A uniform rate of filtration of 3.25 gallons per 

minute, equivalent to a rate of 100,000,000 gallons per acre per day, 

was maintained. The capacity of each of the sedimentation tanks was 

300 gallons to the overflow line, so that one tank alone gave a mean 

storage capacity of one and one-half hours and the two tanks taken 

together three hours. During the first series of tests both sedimentation tanks were used. The following table shows the relation of loss 

of head to the quantity of water filtered, the run in question being a 

fair average of the five made in this way. The results of all the five 

tests were practically identical.

Relation of loss of head to quantity of water filtered.

Time.

1.40 p. m. ..........................................................

2.30 p. m.............................................. I............

3.30 p. m. ..........................................................

Elapsed 

time.

Minutes. 

0

i ^

30

55

55

75

105

135

165

195

Quantity 

filtered.

Gallons. 

0

49

98

178

178

211

308

406

504

600

Loss of 

head.

Inches. 

4

7

8

12

11

14

20

28

.40

55

Between 10.30 a. m. and 1.40 p. m. test shut down. No liquor.

The maximum loss of head possible was 55 inches. The mean results from the above and four similar tests gave 585 gallons of water 

filtered before the loss of head was total.
20 STREAM POLLUTION BY STRAWBOARD WASTE.

One of the sedimentation tanks was then cut out of service and the 

period of sedimentation correspondingly reduced to one and one-half 

hours. Four runs to determine the maximum amount which could be 

past under the conditions gave a mean result of 575 gallons, in practical agreement with that of the first series. It is apparent that a 

period of one and one-half hours was sufficient for the removal of that 

portion of the suspended matter which can be removed by sedimentation. An examination of the water during sedimentation in a glass 

vessel tended to confirm this conclusion. The suspended matter appears to be of two distinct kinds. One is very finely divided and light 

and does not settle out even on prolonged sedimentation. The other 

is granular and heavy and settles rapidly and completely. It was not 

convenient with the apparatus at hand to reduce further the period of 

sedimentation. The laboratory experiments quoted earlier in this 

paper indicated that a period of one hour would accomplish practically 

the same result as more prolonged sedimentation.

AMOUNT OF WASH WATER.

The pressure on the wash-water pipe line was sufficient to give an 

upward flow thru the filter of 25 gallons per minute, or about 12 gallons per minute per square foot of surface. In practise, flows of 8 to 

10 gallons per square foot per minute were used. After each of the 

test runs just described, the filter was washt with an amount of water 

varying from 50 to 100 gallons for two and one-half to five minutes, 

the wash water being carefully measured. Observations of the surface of the filter showed plainly that the shorter period of washing 

was sufficient and that the longer periods did not in any case increase 

the quantity filtered during the succeeding run. The material 

deposited on the surface was exceedingly light and finely divided and 

required but little water for its removal. The stirring device used 

was not well adapted to the purpose, since there was little penetration 

of the sand by the suspended material. An air blast or some device 

which would thoroly agitate the surface before washing would 

undoubtedly make possible the use of still less wash water. Allowing 

50 gallons for each wash, with an average quantity of 575 gallons per 

run filtered, gives a little less than 9 per cent wash water.

The loss of head in these tests bears out a fact of general observation, that the loss of head increases at a fairly constant rate during 

the run. Such being the case, it is quite evident that with a deeper 

filter the quantity filtered between washings would be proportionately 

increased. The amount of wash water would, on the other hand, 

remain constant or increase but slightly. It is therefore safe to say 

that with a filter having an available loss of head of 9 to 12 feet au
MECHANICAL FILTRATION. 21

average run of six hours or more could be maintained and the amount 

of wash water could be reduced to less than 5 per cent.

DISPOSAL OF WASH WATER.

The process, as thus far described, is merely one of concentration 

of the suspended matter. If the above estimate of 5 per cent of wash 

water be correct and the filtered water be used for washing, the net 

result of the process would be the separation of 95 per cent of the 

water in comparatively clean form, leaving the total suspended 

impurity in the remaining 5 per cent of the water. This water might 

be spread upon a small area of land to evaporate, it might be evaporated by artificial means, or, if preferable, it might be filter prest; 

but the most economical way to dispose of it is to return it directly 

to the sedimentation tanks. The material on,the filter is so.prest 

together into small lumps that it settles rapidly. The problem of the 

ultimate disposal of the sludge from the tanks will be taken up in 

another place.

CHARACTER OF EFFLUENT.

Complete chemical analyses of 'the waters before and after treatment during these experiments were neither desirable nor feasible. 

The determination of the total organic solids contained in the waters 

is the only analytical determination which would be of service in estimating the efficiency of the process. This determination might have 

been made by the usual indirect method, i. e., by the difference 

between the total and the fixt or mineral solids. That determination 

is, however, not well adapted to field conditions, and small changes 

in the organic content would be entirely masked by the relatively 

large amount of mineral residue present. It was found in the laboratory studies on the waste liquor that estimating the efficiency of the 

various precipitation methods on the basis of this organic-solids determination and also on the basis of the oxygen-consumed method gave 

practically the same results. In other words, the organic matter 

present is fairly homogeneous in character, as might well be expected, 

and the oxygen-consumed figures, altho purely relative, are therefore 

a reliable measure of the amount of organic matter present. This 

test, therefore, and the determination of the turbidity, or suspended 

solids, by the well-known Jackson turbidimeter method, were used 

in this work to determine the quantity of the organic and the suspended matter, respectively.

During the two three-hour runs samples for analysis were collected 

every ten minutes from the raw liquor, sedimented liquor, and final 

effluent, the small samples being mixt together to obtain an average
STKEAM POLLUTION BY STKAWBOARD WASTE.

sample for the run. In both cases the rate was maintained at 3.25 

gallons per minute. The following data of the test were obtained:

Data from test run of filter.

Test No.

7.............................................................

8.............................................................

Duration.

Hours. 

2.9 

3

Loss of head.

Initial. .

Inches. 

4 

3

Final.

Inches.

55 

55

Quantity 

filtered'

Gallons. 

566

585

The chemical analyses for the two sets were very similar, 

lowing table shows the mean values obtained:

Analyses of raiv liquor, settled liquor, and effluent.

The fol-

-Raw liquor. 

Oxygen consumed: 

Total ...........................................................................

Settled liquor. 

Oxygen consumed: 

Total ...........................................................................

Effluent. 

Oxygen consumed: 

Total ...........................................................................

Parts per 

million.

9,400

2,000

7,400

28,000

6,200

1,600

4,600

4,400

2,200

1,700

500

575

Per cent 

removed.

34

20

38

84

77

15

93

98

The appearance of the effluent frequently changed materially during the run. Contrary to expectations and general experience, the 

best effluent was always obtained during the early part of the run. 

The very first portions of effluent were generally slightly turbid, 

after which a perfectly clear water came thru, as a rule, entirely free 

from suspended matter. This state of affairs continued until the loss 

of head had reached about 6 or 8 inches, when the effluent suddenly 

became turbid and continued so uniformly until the end. The inference was that under a tension or pull on the surface film represented 

by about 6 to'8 inches of head the finely divided matter contained in 

the liquor was pulled thru the surface and then thru the filter. It 

was thought that if this should be a correct interpretation of the phenomenon, it might be obviated in one of two ways by increasing the 

toughness of the surface deposit, or by decreasing the size of the sand 

pores by use of a layer of finer material on the surface. Both of 

these methods were tried.
CHARACTER OF EFFLUENT. 23

To increase the density and toughness of the surface film the surface was covered with liquor, the outlet being closed, and 2 ounces of 

sulfate of aluminum were added and stirred in. Fifteen minutes 

were allowed for the formation and settling of the precipitate, and the 

filter was then started. The following data were obtained:

Data of test run of filter after addition of alum.

Duration of run.........................................hours.. 1.9

Loss of head:

Initial...................:.........................inches.. 14

Final................ % ............................... do.... 55

Quantity filtered.......................................gallons.. 370

The chemical analyses resulted as follows:

Analyses of raw liquor, of settled liquor, and of effluent after the addition of alum.

Raw liquor. 

Oxygen consumed: 

Total............................................................... ...........

Settled liquor. 

Oxygen consumed: 

Total...........................................................................

Effluent. 

Oxygen consumed: 

Total.... ......................................................................

Parts per 

million.

9,000

1,600

7,400

27,300

6,000

1,600

4,400

4,500

1,800

1,600

200

450

Per cent 

removed.

33

6

40

84

80

0

98

93

The improvement of this effluent over that obtained without a 

coagulant is decided, but is hardly sufficient to warrant the extra cost 

of treatment. Previous studies had shown that it was necessary to 

add to the volume of waste on the surface of the filter at least 2 ounces 

of alum in order to bring about a satisfactory precipitation of the 

lime. Any less amount would not have produced a satisfactory precipitation in a short time. The total quantity filtered during the run 

was 370 gallons. This gives an amount of sulfate equal to a little over 

2 grains per gallon for the entire run, or a consumption of 300 pounds 

of alum per million gallons. At a cost of 1 cent per pound (based on 

net weight of sulfate of aluminum in the crude compound) this would 

amount to $3 per million gallons of waste, or 10 cents per ton of 

finished board. This additional cost for chemicals, together with the 

slightly additional expenditure for labor and water required by more 

frequent washing, would not seem to be justified in general by the 

slightly increased purity of the effluent. The results are given here
24 STKEAM POLLUTION BY STRAWBOAKD WASTE.

and the cost estimated as a matter of record and in order to show what 

could be accomplished by the process if it were deemed desirable in 

any special case.

The second plan for preventing the small suspended particles in the 

liquor being drawn thru the surface was to use a surface layer of fine 

sand. A suitable grade of sand was obtained locally and screened 

thru a No. 20 screen. The sand thus prepared contained a considerable amount of rather fine materal. Mechanical analysis showed 

that it had an effective size of 0.26 mm. and a uniformity coefficient 

of 2.0.

A 6-inch layer of the sand was placed on the top of the filter and 

washt. After washing, the surface was examined and found to consist of a well-mixt layer of coarse and fine material. Two runs were 

made with the filter as thus prepared. The following are the average 

data obtained:

Data of test run of filter after addition of fine sand.

Duration of run.......................................hours.. 2. 3

Loss of head:

Initial...........................................inches.. 6

Final .............................................do.... 55

Quantity filtered .......... .........................gallons.. 449

The appearance of these effluents was such that chemical analyses 

were not made. They were essentially like the others, and there was 

no advantage in the use of the layer of fine sand which could in any 

way offset the obvious disadvantage of the much shorter run.

THE SLUDGE.

Amount and composition. Thruout the experiments, except for the 

first few runs, the dirty wash water from the filter was run back into 

the sedimentation tanks. Eventually, therefore, all the material 

removed from the waste liquor was accumulated in the bottom of these 

tanks. At the conclusion of the experiments, which consisted altogether of 12 runs, dealing with a total of 4,900 gallons of the waste, 

the liquor was drawn off from the tanks as far as possible and the 

depth of accumulated sludge and remaining liquor was measured. The 

average depth was found to be 6 inches. After thoro mixing a sample 

of the sludge was collected and allowed to stand in a glass cylinder for 

two hours. From a column of sludge 12 inches in depth a 2-inch layer 

of clear liquid separated at the top, leaving the depth of sludge on the 

bottom 10 inches. Therefore the 6 inches of sludge and liquor left in 

the tank was composed of 5 inches of sludge and 1 inch of water, so 

that 5 inches represents very closely the average depth of sludge in 

each tank and will be used in the calculations which follow.
THE SLUDGE. 25

Analysis of the sludge gave the following results:

Analysis of sludge resulting from filtration of straivboard waste.

Specific gravity.............................................. 1.094

Total solids .....-....-...-..............._........per cent.. 19.4

Volatile ..........................................do.... 9.8

Fixt .............................................do.... 9.6

From these data the following results are obtained:

Sludge in tank.......................................gallons.. 178

Liquor treated .........................................do.... 4,900

Per cent of sludge (by volume)................................ 1.6

From 1,000,000 gallons of waste there will be obtained 

Sludge.........................................cubic yards.. 79

Dry solids..........................................pounds.. 28,000

Organic solids ....................................dtf.... 14,100

Mineral solids ....................................do.... 13,900

For each ton of strawboard there will be produced 

Sludge.....................:.................. .cubic yards.. 4. 7

Dry solids..........................................pounds.. 1,680

A glance at PI. I, B, will indicate what these figures mean. The 

piles of straw there shown represent three months' supply for a 

mill producing 30 tons of board per day. Over one-third of the total 

weight of this straw will appear in the waste liquor.

Properties and uses of the sludge. As is indicated by the analysis, 

the sludge is a thick mud. It is dark muddy brown in color, and has 

the odor of straw. On exposure to the air it dries much more rapidly 

than would be expected, owing largely to the action of the air on the 

free lime. If allowed to dry in a mold, the resulting cast comes away 

clear and has taken a very clean impression of the mold. It is very 

brittle by itself. If, however, a little paper fiber be rnixt with it 

before drying, the dry cast is fairly tough. Such a mixture could 

undoubtedly be used in many places as a cheap substitute for papiermache.

The dry product had a specific gravity of 0.62. It will readily 

absorb considerably more than its own weight of water. Its porous 

nature suggests its use as a heat insulator, particularly in refrigerators.

This material possesses a certain value as a fertilizer. It contains 

a considerable proportion of calcium carbonate, a substance beneficial 

to cultivated land. It also contains 0.3tt per cent of phosphoric acid 

in an available form. Its loose, porous nature makes it particularly 

valuable for use on clay land, as such land is made much more porous 

by it and at the same time is sufficiently fine to retain the moisture well. 

This point was well brought out on examining one of the abandoned 

settling basins. This basin had originally been diked up about 6 feet
26 STREAM' POLLUTION BY STRAWBOARD WASTE.

above the surrounding fields, and had subsequently been completely 

filled with the sludge. On digging into this deposit, standing water 

was observed at a depth of less than 2 feet below the surface, altho 

the ground-water level in the adjacent fields was at least 6 feet lower 

and the field had not been flooded for over a year.

Some experiments have been made with this solid residue as a base 

for the production of a sulfur dye. Fusion of the substance with 

twice its weight of a mixture of one part of sulfur and two of sodium 

sulfide yields a mass containing a considerable proportion, perhaps 

20 per cent, of a brown sulfur dye. Purification of the resulting dye 

from the mass of inert material was not attempted, and further study 

is required to determine the most satisfactory procedure for the preparation and purification of this dye, but enough has been done to indicate that a low-grade sulfur dye can be made from this waste material. 

It dyes unmordanted cotton a good warm shade of brown, is fast to 

hot soap and to sunlight, and compares favorably in color and fastness 

with dyes on the market selling at 15 cents per pound.

Considerable attention has been given to the problem of finding 

profitable use for the residual organic matter which is the end product 

of the filtration processes here recommended. Altho the satisfactory 

solution of this problem would be highly desirable and would at once 

assure the treatment of all strawboard waste liquors, it must be remembered that this is merely a question incidental to the main problem. 

It is believed that the process of sedimentation, followed by mechanical filtration, essentially as described, furnishes by itself a solution of 

that problem which will prove of financial advantage to the manufacturers and of lasting benefit to all who have an interest in the purity 

of the streams below. It was therefore not deemed pertinent to the 

present investigation to pursue further the question of the utilization 

of the sludge. The suggestions here given, and particularly that in 

regard to the preparation of a dye, are merely intended to indicate 

the direction in which, according to the writer's views, future research 

would bring results of value.

RESUME OF METHOD OF TREATMENT.

The following plan of treatment is recommended: The waste water 

from the beaters should be past thru a properly designed settling tank 

of such size that it will give a period of about one hour's storage. A 

tank built on the principle of the Dortmund tank would be preferable 

to any other, owing to its compactness and the possibility of continuous use. The tank should have a capacity of approximately 1,200 

gallons for each ton of board produced per day by the mill.

The water should pass fronl the tank directly to the filters, which 

should be built in small units. The filters should have an available 

loss of head of at least 12 feet, and could be run at a rate of 100,000,000
METHOD OF TREATMENT. 27

gallons per acre per day. This would necessitate a filter area of 

approximately 16 square feet per ton of board produced daily. This 

figure allows 10 per cent excess for repairs and washing.

The effluent should be pumped and used again for washing the filter 

and for beater wash water. It would at all times contain less impurity than does the very last water past from the beaters and its use 

during the early part of the washing process could do no possible 

harm. To insure a proper washing out of the last of the lime from 

the stock it would probably be found necessary to complete the washing with fresh water. In any case a saving of one-half to two-thirds 

of the amount of wash water now used could be realized, the amount 

of waste liquor being correspondingly reduced. The water used in 

washing the filter should be returned to the sedimentation tank and 

would require no further treatment.

The sludge from the sedimentation tank could be most expeditiously dealt with by filter pressing. There ^tmld remain a fairly 

dry and hard press cake, which would require disposal unless some 

profitable use for it be found. Under the influence of the air and 

sun this material is speedily resolved into mineral matter, forming a 

sort of soil. It could be spread upon low land in thin layers and 

would then take care of itself.

Instead of being filter prest, the sludge might be discharged upon 

small areas of sandy soil where such are available or even upon somewhat larger areas of less porous soil, and allowed to dry out by draining and evaporation. The dry layer of sludge could then be removed 

and disposed of. No accumulation of the wet material should be 

allowed. When once dried out and subjected to the action of the 

sunlight and air it soon becomes harmless, but in deep beds and constantly covered with water it is subject to all the offensive putrefaction 

described in the case of the sedimentation fields. This process of spontaneous draining and drying out would probably be found the cheaper, 

but would require a considerable area of suitable land and would 

also involve more careful supervision. The amount of land required 

would depend wholly on the quality of the drainage. For average 

conditions it may be roughly estimated at 1,000 square feet per ton of 

board produced by the mill daily. The dried sludge would require 

removal before the application of more sludge.

CHARACTER OP WASTE WATER AFTER TREATMENT.

The quality of the effluent from the proposed process is not all that 

could be desired. In spite of the fact that it is possible to remove over 

90 per cent of the suspended organic matter present in the liquor the 

resulting effluent is still putrescible. That is, a bottle of the liquor 

s but up air-tight and kept at a warm temperature will in the course of 

a few days undergo putrefactive fermentation. The putrefaction is
28 STREAM POLLUTION BY STRAWBOAED WASTE.

rather slow, however, and not offensive. In admixture with an equal 

volume of tap water the effluent does not putrefy even when inoculated with a small amount of sewage.

The fact that the effluent is practically free from gross suspended 

solids that is, solids which will settle out on the bed of the stream is 

of greater significance than the analytical data. As was pointed out 

in the earlier discussion of the problem (p. 8), by far the greater 

part of the damage done to the polluted streams is brought about by 

the deposit of material in the stream beds. The effluent which has 

past the treatment here outlined will contain no material capable of 

settling out even in slack water.

Tlie conclusion is therefore justified that the discharge of this effluent 

into a stream whose minimum flow equals in volume the flow from 

the mill would not produce a nuisance. With no allowance for a 

possible diminution of the amount of wash water, if used as suggested 

above, this means that the minimum stream flow must be at least 0.05 

cubic foot per second per ton of board produced daily at the mill. A 

minimum flow of 0.1 cubic foot per second per daily ton would therefore provide for a generous factor of safety if the stream is reasonably unpolluted at the point of discharge.

The discharge of such an effluent into a stream highly polluted with 

sewage would probably be accompanied by an aggravation of the conditions already existing. There would, as usual, be a precipitation of 

the sewage material by the lime of the effluent. In all fairness it could 

be maintained that the organic matter of the effluent was not contributing to the nuisance. If, therefore, it should be decided that the addition of lime to a sewage-polluted stream constitutes a nuisance, further 

treatment of the effluent would be required to remove this caustic lime. 

If, on the other hand, as would seem to be reasonable, it should appear 

that the real pollution of the stream lay in the sewage and the lime was 

incidental and was there by right, there would be no reason for such 

further treatment.

COST OP THE PROCESS.

The cost of the process recommended can not be discust in detail at 

this time. It would be largely the cost of installation. The design 

and construction of a suitable plant require expert attention and the 

cost of the plant would depend somewhat on local conditions. The cost 

of maintenance would be slight. The cost of additional pumping to 

supply wash water say 5 per cent more than the present amount 

pumped can be determined readily. The services of one man, who 

could also assist in the mill part of the time, would be a sufficient addition for running the plant. The power necessary to pump the sludge 

thru the filter presses, if that plan were adopted, would not be noticeable in comparison with the total power used in the mill. If the sludge
SUMMARY. .29

were disposed of by the other plan, evaporation and drying" in the field, 

the services of another man would be required.

In conclusion, the following summary of the chief points of the 

present paper may be made:

SUMMARY. -

The present method employed for the treatment of strawboard waste 

liquor, that of sedimentation in large fields, is unsatisfactory and 

expensive and proceeds on a wrong principle.

The filtration of the liquor thru sand, so-called mechanical filtration, 

but without coagulants, after a short period of sedimentation will 

remove 93 per cent of the suspended organic solids and 98 per cent of 

the total suspended matter determined as turbidity.

Actual experiments have shown that the resulting effluent can be 

discharged into an equal volume of reasonably pure water without 

creating a nuisance. In particular, there will be no sedimentation 

of organic matter. If its discharge into a seriously polluted stream 

should bring about precipitation of sewage matter and consequent 

nuisance, the blame should in all equity be fixt on those contributing 

the sewage.

T'he sludge resulting from the sedimentation tanks, after pressing or 

spontaneous drying, is innocuous and makes good soil. It has some 

value as a fertilizer and is particularly valuable to mix with the clay 

soils of the Middle West to render them more porous. Other uses for 

thin material are suggested, but they require further study.

The cost of the entire process is sufficiently low to admit of its adoption wherever stream pollution is serious.

CLASSIFICATION OF THE PUBLICATIONS OF THE UNITED STATES GEOLOGICAL

SURVEY.

[Water-Supply Paper No. 189.]

The serial publications of the United States Geological Survey consist of (1) 

Annual Reports, (2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral 

Resources, (6) Water-Supply and Irrigation Papers, (7) Topographic Atlas of United 

States folios and separate sheets thereof, (8) Geologic Atlas of United States 

folios thereof. The classes numbered 2, 7, and 8 are sold at cost of publication; the 

others are distributed free. A circular giving complete lists can be had on application.

Most of the above publications can be obtained or consulted in the following ways:

1. A limited number are delivered to the Director of the Survey, from whom they 

can be obtained, free of charge (except classes 2, 7, and 8), oJiapplication.

2. A certain number are delivered to Senators and RepresentfPa^yn Congress, 

for distribution. , "^^^lhl&

3. Other copies are deposited with the Superintendent of Documents, A$iS[jngton, 

D. C., from whom they can be had at.practically cost. "^ ^ " ,

4. Copies of all Government publications are furnished to the principal public 

libraries in the large cities thruout the United States, where they can be consulted 

by those interested.

The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of 

subjects, and the total number issued is large. They have therefore been classified 

into the following series: A, Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; D, Petrography and mineralogy; E, Chemistry and 

physics; F, Geography; G, Miscellaneous; H, Forestry; I, Irrigation; J, Water storage; K, Pumping water; L, Quality of water; M, General hydrographic investigations; N, Water power; O, Underground waters; P, Hydrographic progress reports. 

This paper is the seventeenth in Series L, the complete list of which follows (WS= 

Water-Supply Paper):

SERIES L, QUALITY OP WATER.

WS 3. Sewage irrigation, by G. W. Rafter. 1897. 100 pp., 4 pis. (Out of stock.)

WS 22. Sewage irrigation, Pt. II, by G. W. Rafter. 1899. 100 pp., 7 pis. (Out of stock.)

WS 72. Sewage pollution near New York City, by M. O. Leigh ton. 1902. 75 pp., 8 pis.

WS 76. Flow of rivers near New York City, by H. A. Pressey. 1903. 108 pp., 13 pis.

WS 79. Normal and polluted waters in northeastern United States, by M. O. Leighton. 1903. 192 pp.,

15 pis. 

WS 103. Review of the laws forbidding pollution of inland waters in the United States, by E. B.

Goodell. 1904. 120pp. 

WS 108. Quality of water in the Susquehanna River drainage basin, by M. O. .Leighton, with an

introductory chapter on physiographic features, by G. B. Hollister. 1904. 76pp., 4 pis. 

WS 113. Strawboard and oil wastes, by R. L. Sackett and Isaiah Bowman. 1905. 52 pp., 4 pis. 

WS 121. Preliminary report on the pollution of Lake Champlain, by M. O. Leighton. 1905. 119 pp.,

13 pis. 

WS 144. The normal distribution of chlorine in the natural waters of New York and New England,

by D. D. Jackson. 1905. 31pp., 5 pis.

WS 151. Field assay of water, by M.O. Leighton. 1905. 77pp., 4 pis. 

WS 152. A review of the laws forbidding pollution of inland waters in the United States, second

edition, by E. B. Goodell. 1905. 149 pp.
SERIES LIST.

WS 161. Quality of water in upper Ohio River basin and at Erie, Pa., by S. J. Lewis. 1906. 114 pp.,

6 pis. 

'WS-179. Prevention of stream pollution by distillery refuse, based on investigations at Lynchburg,

Ohio, by Herman Stabler. 1906. 34 pp., 1 pi. 

WS 185. Investigations on the purification of Boston sewage, by C. E. A. Winslow and Earle B.

Phelps. 1906. pp. 

WS. 186. Stream pollution by acid-iron wastes, a report based on investigations made at Shelby, Ohio,

r by Herman Stabler. 1906. 36 pp., 1 pi.

WS. 189. The prevention of stream pollution by strawboard waste, by Earle Bernard Phelps. 1906. 

* 29 pp., 2 pis.

Correspondence should be addrest to

THE DIRECTOK,

UNITED STATES GEOLOGICAL SURVEY,

WASHINGTON, D. C. 

DECEMBER, 1906.

o