Reduction of water solids contributions to apparent cotton dust levels through use of special water in atomizers

A method of treating the water supplied for humidification of the textile processing room environment (e.g. weaving room) results in reduced apparent cotton dust concentrations, while maintaining or increasing processing efficiency. The water supplied to the humidification system for the processing environment is pure water, such as reverse osmosis water, distilled water, deionized water, demineralized water, etc. Humidification is primarily achieved utilizing atomizers, and a pure water supply can be generated on-site by treating tap water with conventional deionizers or demineralizers.

BACKGROUND AND SUMMARY OF THE INVENTION 
In conventional cotton textile processing room environments, such as 
weaving rooms, traditionally the air has become contaminated with cotton 
dust. The term "cotton dust" is defined in this art area as any dust 
present during the handling and processing of cotton through the weaving 
or knitting of fabrics and dust present in other operations or 
manufacturing processes using new or waste cotton fibers or cotton fiber 
byproducts from textile mills. Increasing concern has been expressed over 
the years that such cotton dust is a causative agent of byssinosis, and 
standards have been promulgated by regulatory agencies (e.g. OSHA) 
controlling the amount of cotton dust that may be present in a textile 
processing environment, such as a carding room or weaving room. 
Various attempts have been made to reduce the cotton dust level in various 
environments in order to comply with regulatory standards, and such steps 
have often involved the purchase and utilization of expensive equipment, 
particularly dust capturing and filtration equipment such as that attached 
to individual pieces of machinery. Also, there have been proposals to more 
thoroughly clean cotton prior to baling and receipt at the textile 
operation centers. Such techniques have met with mixed succes despite high 
costs often associated therewith, and the basic changes in textile 
operations that they involve. 
According to the present invention it has been recognized that a large 
component of the apparent cotton dust levels in textile processing 
environments is from mineral or other solids in humidification water 
supplied to the processing environment, as by atomizers and air washers. 
Such mineral solids in many cases can account for 250 micrograms per cubic 
meter of air of cotton dust; this alone exceeds the present OSHA standard 
of 200 micrograms per cubic meter for some textile processing areas. 
According to the present invention, it has been found that the mineral 
component of the apparent cotton dust level can be fantastically reduced, 
with textile processing efficiency maintained the same or even increased, 
in a simple and inexpensive manner. The primary thrust of the present 
invention is to supply low solids content or pure water to the 
humidification system (e.g. atomizers) for the textile processing room 
environment. The pure water may be distilled water, demineralized water, 
deionized water, reverse osmosis water, boiler condensate water, or 
ultra-filtration water. The term "pure" as used in the present 
specification and claims encompasses all such types of low solids 
(dissolved or suspended) water. While of course no water can be completely 
"pure" (and completely "pure" water could, in fact, be too corrosive of 
the equipment), it is desirable to utilize water as pure as possible in 
practicing the present invention, and in any event the water to be 
considered "pure" within the context of the present specification and 
claims must be sufficiently free of mineral solids and the like to, when 
utilized in a humidification system for a textile processing environment, 
reduce the mineral solids component of cotton dust to acceptable levels. 
Merely by practicing the simple method according to the present invention, 
it is possible, for example, to reduce the apparent cotton dust 
concentration in a weaving room from above 750 micrograms per cubic meter 
to about 100 micrograms per cubic meter. And, this is sometimes achieved 
with improved weaving efficiency. 
The utilization of deionized or demineralized water in humidification 
environments in general has been known heretofore, such as shown in U.S. 
Pat. No. 3,776,530. However such deionization or demineralization has been 
practiced for other purposes (preventing humidifier clogging, for 
example), and it has not heretofore been recognized that the utilization 
of pure water in a textile processing environment can have the unexpected 
and surprisingly significant reduction in apparent cotton dust level that 
is possible according to the present invention. 
According to one aspect of the present invention, a method of maintaining 
low apparent cotton dust concentrations and proper humidity in a textile 
processing room is provided. The method consists essentially of the step 
of supplying pure water to atomizers which deliver water to the atmosphere 
in the textile processing room environment. A mineral solids component of 
apparent cotton dust concentrations is particularly significant in textile 
processing rooms where atomizers are utilized for humidification, and 
where the relative humidity must be maintained high (e.g. 80%, as in a 
weaving room) in order for processing to be effective, although the method 
is applicable to other humdification systems, such as air washers. Of 
course the amount of humidification is also dependent upon a number of 
other variables including the extent to which water vapor is removed from 
recirculated air by airconditioning (condensation) processes, the extent 
to which "fresh" air is mixed with recirculated air and the net difference 
in indoor and fresh water-vapor mass, the particle-size distribution of 
the aerosol or solids resulting from humidification, and the effective 
rate of removal of the aerosol or solids by other techniques, such as 
filtration, settling, or leakage processes. In any event, however, the 
practice of the present invention can result in extremely significant 
reductions in the apparent cotton dust level in a textile processing room 
environment. 
According to another aspect of the present invention, a method of 
maintaining proper humidity within a textile processing room environment 
is provided. The method comprises the steps of providing a humidification 
system for the textile processing room environment; providing a source of 
tap water at the textile processing room environment; treating the tap 
water from the tap water source at the textile processing room environment 
to produce pure water; and feeding only pure water, including that 
obtained from treatment of the tap water to the humidification system for 
humidifying the textile processing room environment. The treatment step 
may be effected by demineralizing or deionizing the water, utilizing 
conventional deionizing and demineralizing equipment. 
According to yet another aspect of the present invention, a method of 
treating the air in a textile weaving room environment is provided. The 
method comprises the steps of providing atomizers in operative association 
with the weaving room environment for delivering atomized water into the 
weaving room atmosphere; and supplying only pure water to the atomizers to 
be delivered into the weaving room atmosphere. 
According to yet another aspect of the present invention a method of 
conditioning a textile processing room air supply is provided, which 
supply if unconditioned will result in too high a concentration of cotton 
dust in the textile processing room, and utilizing an air recirculating 
system and a humidification system disposed in the air recirculating 
system. The method comprises the steps of: (a) Withdrawing air from the 
textile processing room with the air recirculating system. (b) Supplying 
pure water to the humidification system. (c) Effecting humidification of 
the air withdrawn from the textile processing room with the pure water 
delivered to the humidification system; and (d) returning the humidified 
air to the textile processing room environment. Between steps (a) and (d) 
the withdrawn air may be filtered and mixed with air from an exterior air 
source ("fresh" air), and the humidification system preferably comprises a 
plurality of atomizers to which the pure water is supplied. The pure water 
is selected from the group consisting essentially of deionized water, 
demineralized water, distilled water, reverse osmosis water, boiler 
condensate water, and ultrafiltration water, although any water source 
providing water of sufficient "purity" for significantly reducing apparent 
cotton dust concentrations is appropriate. 
The invention also has an aspect thereof a method of improving weaving 
efficiency by humidification of the weaving room atmosphere to a 
predetermined level with atomizers, the improvement consisting essentially 
of the step of delivering pure water to the atomizers for humidification 
of the air. 
It is the primary ob]ect of the present invention to provide a simple and 
effective method for reducing the apparent cotton dust concentration in 
textile processing room environments, while maintaining or increasing 
textile processing efficiency. This and other objects of the invention 
will become clear from an inspection of the detailed description of the 
invention, and from the appended claims.

DETAILED DESCRIPTION OF THE INVENTION 
With reference to the accompanying drawings, a typical textile processing 
environment is illustrated at 10 in FIG. 1 and at 10' in FIG. 2, such as a 
weaving room, a carding room or a spinning room. The invention is 
particularly applicable to those textile processing environments that 
require high relative humidity (that is where there is no alternative but 
to artificially humidify the atmosphere), such as weaving, carding and 
spinning rooms. 
In the schematic drawing illustrated in FIG. 1, air is withdrawn for 
reprocessing from the environment 10 through a conduit 12, as under the 
influence of a blower 14, and is ultimately passed to an air conditioning 
system 16, commonly an air washer or the equivalent. Prior to (or 
subsequent to) humidification within the air recirculating system, the air 
may be filtered at station 18, and/or mixed with fresh air at station 20, 
the fresh air being supplied from source 22. Filtration may be 
accomplished utilizing a V-cell lint-capture system, or other filtration 
or like treatment apparatus. Mixing in station 20 is accomplished 
utilizing conventional techniques and apparatus. Ultimately, the treated 
air is recirculated to the environment 10 through conduit 24. 
At the air conditioning station, humidification apparatus will be provided, 
such as one or more atomizers 25. It is understood that there exist 
several atomizer means, including single fluid, water pressure driven, two 
fluid, air pressure driven, spinning dics, and the like. According to the 
present invention, pure water is supplied to such atomizers 25. 
In the embodiment illustrated in FIG. 1, pure water is obtained by 
providing tap water in line 26 to a water treatment station 28. [The term 
"tap" as used in the present specification and claims refers to water from 
conventional municipal or private water systems, or other conventional 
potable sources.]At the water treatment station the water is rendered pure 
enough to effect the cotton dust level reduction achievable according to 
the present invention. For instance the water treatment station 28 may 
comprise conventional deionizing or demineralizing equipment (see, for 
example, U.S. Pat. Nos. 3,776,530 and 4,157,963, the disclosures of which 
are hereby incorporated by reference herein). Only the pure water from the 
treatment station 28, which may be blended with some tap water as long as 
the blend itself is "pure" as defined herein, is supplied to the atomizers 
25. 
Another source of air to be treated is the air from the machinery dust 
collection equipment, illustrated schematically at 32 in FIG. 1, located 
in the textile processing room 10. The removed air from equipment 32 
passes through conduit 33 to a primary filter 34, secondary filter 35, and 
optionally a tertiary filter 36, and then to mixing station 20. 
In the utilization of a water atomizer, such as the spray nozzles 25, 
normally there will be excess water, which passes into line 38 and 
subsequently to sump 39. At sump 39 chemicals, such as algecides, 
slimisides, etc., are added from source 40, and after treatment, it is 
returned to the water inlet to atomizers 25 through line 42, using a pump 
if needed. 
A tap water source 26' may be provided to add water to sump 39 if the water 
level should get too low. Also, a demister 44 may be provided in conduit 
24 to prevent large water particles from entering environment 10. 
FIG. 2 schematically illustrates another exemplary manner in which the 
method according to the present invention may be practiced. In this 
embodiment atomizers 25' are disposed directly in the textile processing 
environment 10'. Pure water is supplied to the atomizers 25' from the pure 
water supply 30. The pure water supply 45 may be obtained by treating tap 
water at the textile processing environment (as illustrated in FIG. 1), or 
the pure water may be provided from some extraneous supply. Distilled 
water, deionized water, demineralized . water, reverse osmosis water, 
boiler condensate water, and ultra-filtration water are all commonly pure 
enough to be considered "pure" water within the context of the present 
invention, and can achieve the desired apparent cotton dust level 
reductions and enhance textile processing efficiencies according to the 
invention. A tap water source 26" provides primary feed water for the pure 
water supply 45. 
In a typical application of the present invention, a weaving room utilizing 
atomizers for providing humidification thereof was found to have an 
apparent cotton dust level of over 750 micrograms per cubic meter. 
According to the present invention, tap water from a city water supply was 
run through a conventional deionizer before being supplied to the 
atomizers. This step alone, while maintaining all other parameters 
essentially the same, resulted in a reduction of cotton dust concentration 
to the level of about 100 micrograms per cubic meter. At the same time, 
there was a small but noticeable improvement in weaving efficiency, 
believed due to fewer particles to interfere with weaving. The costs 
associated with providing and running the deionizer were the only costs 
necessary to achieve such significant advantageous results. 
It will thus be seen that according to the present invention a simple and 
effective method has been provided for reducing apparent cotton dust 
concentrations to acceptable levels in textile processing room 
environments, while at the same time maintaining or increasing textile 
processing efficiencies. While the invention has been herein shown and 
described in what is presently conceived to be the most practical and 
preferred embodiment thereof, it will be apparent to those of ordinary 
skill in the art that many modifications may be made thereof within the 
scope of the present invention, which scope is to be accorded the broadest 
interpretation of the appended claims in order to encompass all equivalent 
methods and processes.