Recycling Sewage Water For Scouring and Dyeing

By Dr. R. P. Harker Group Manaager, Coloration, Finishing,Water and Effluent Wira Leeds, England

IJ Between 1970-1973,an important piece of coopera- phaseof thework is receivingsimilar support fr tive research was carried out in the, then, Borough of GARB(Garment & AlliedIndustries Requireme Pudsey (West Ridingof Yorkshire). The objectiveof the Board. work was to show that sewage effluent,.properly treated, could beused as a main water supply for textile Background processing. Takingpart inthe experimental work The Borough of Pudsey is situated betweenthe c11 were Messrs. Henry Lister and Sons Ltd., a branch of of Leeds and Bradford and has a Dstulation of so Courtaulds and the prospective water user, the Water 40,000 persons. Although it is probabiy best known Pollution Control Departmentof Pudsey Borough Coun- cil,the prospective suppliers, and Wiraacting in a monitoringand advisory capacity. The initial pilot scheme, which became known as the Pudsey Project and hasbeen fullydescribed elsewhere, is presented here in outline. The finalphase of the experiment, that dale Mill of Messrs.Henry Lister and Son of connectingthe whole mill to the useof re-cycled water, commenced July 1, 1977, and was scheduled to finish by June30, 1979. This part of the work will again be a cooperative effort: Messrs. Henry Lister and Sons Ltd and Wira will carry out and monitor full-scale wet processing trialsand the Yorkshire Water Authority (YWA) and Wira will monitor the water supply to the to the works inlet. The total water consumption at mill.The initial work receivedconsiderable support mill isapproximately 1,136 M3/day. from the Department of the Environment and the last The mill has for many years derived its water fr

Table I. Water analyses.

Softened Humus tank Land filtration W ell well Well effluent area effluent water at water at Property

pH 77.2 .O 10.6 2 2 Brown Color (Hazen) 2 2 Turbidity - (Formazin Units) 2.5 3 .O 290 Suspended solids (mg/l) Nil NII 57 48 0 280 930 Total dissolved solids (mg/l)280 480 28 2 48 1 64 Carbonate hardness1 as CaCO, (mg/l)48 282 4 0 Nil Nil Non carbonate hardnessNil as CaCO, (mg/l) 40 Total hardness as CaCO, (mg/l) 322 4864 1 Total alkalinity as CaCO, (mg/l) 282 76 220 22 0 28 108 Calcium hardness as CaCO,28 (mg/l) 220 1 02 20 56 Magnesium hardness as20 CaCO, (mg/l) 102 Acidity to pH 8.3 at CO, (mg/l) 35 - 25 Iron filtered sample at Fe (mg/l) 0.25 0.03 Nil Iron -total as Fe (mg/l) Nil 0.18 0.85 Manganese in filtered sample as Mn (mg/l) 0.16 Nil 0.10 Chlorion (mg/l) 36 36 21 2 Nitrites as N (mg/l) Nil 0.05 1.o Nitrates as N (mg/l) 9.2 Trace Trace ount of 0.8 0.6 29.4 Permanganate value (mg/l)0.6 0.8 Chlorine absorbed Chlorine as CI, (mg/l) 0.9 0.7 74.5

28 AmerlcanDyestuff Reporter January Circle 13 on Reader Service Table 11. Experimental sand filter. Stage 1 (a)To establishthat the effluent from Hought.)kre's why Rot October to December 1968 Works was potentially of a sufficiently high qualiti(W textile printi warrant aninvestigation into its effects upon clot. RHOPLEX 2 Hum us tank FilteredHumustank used in textile processing. Property effluent effluent effluent Property (b) TO justify, by laboratoryexperiments, the available at version of partof themill production to the usem We offer a k pH 7.1 7.1 effluent. We SUPPI!, 2 Suspended9 sollds (rngil) 52 (c) To convert part of themill production, with m. RHOPLEX' BOD (rngil) 12 25 toringof the effect of theuse of effluent upon p' modlflers, essesinvolved in the production of a variety of V, COD (rngil) 72 122 surfact,?:1ts. PV (rngil) 11.5 18.2 textile fabrics. Chlorion (rngil) 146 146 Stage 1 was completed and reported to the Dei.. Our r€?SealC Nitrites as N (rngil) 0.1 7 0.28 ment theof Environment by January 1974. pr0duct.s yo Nitrates as N (rngil)16.3 15.8 binders, nor Arnrnonlacal nltrogen2.15 as N (rngil) 2.27 Stage 2 chemrcals, I The convekion of the entire mill production to iree sources: (1) a private well; (2) the Pudsey Beck; use of recycled water from sewage effluent. Suit;Al*ough We'rE and (3) town water. largescale treatment facilities have been desiymall enough Generallyspeaking the demands so far as process and installed at the Houghside Works of the 'forkst @'e You Intent waterare concerned have been met from sources (1) Water Authority (YWA), and the supply system to.kMtlle Qrlntlng; and (2). Source (1) provides an excellent quality water, millcommissioned so thatStage 2 could be irn:mlormatlon ba m en ted. samples andic but the amount available issamples diminishing. Source (2) is mented. unsuitable in times of highflow, largely due to the presence of excessive amounts of suspended solids. In Feasibility studies-Stage 1 [a] the event of any failure insources (1) and (2), source (3) Sewage is treated at Houghside Works by filtratr is utilized. It is, however, expensive and its use has the with recirculation of effluent. followed bv irrioatioom %HI effect of denuding domestic users ofwater in other land filtration areas. In 1968 the works w'as rGuirf parts of the town. The mill has problems, therefore, in comply withthe river authority standard. While meeting Its presentwater demand incertain circum- was not achieved in the humus tank effluent, the li stances. Theseproblems are likely to become more area effluent was wellwithin the standard. Tab1 acute andcertainly any future expansioncould be shows the analysesof wellwater, before and al seriously restricted by water considerations. softening, in use at the mill, and the works humusti andland area effluents. It appearedthat the expl Objectives mentshould be concerned withthe use, at I From the original concept the workdeveloped in a rate initially, of an effluent of a similar quality to li natural sequence of events, including the involvement area effluent. of the Department of the Environment, and culminating However, it is difficult from a geographical poi in the present project designedto lead to conversion of view to convey landarea effluent to themill the whole of the processing at the mill to the use of ef- consequently thoughts were centered upon mechan fluent water. The sequence may be briefly described in means of improving the humus tank effluent. It I the followingstages. furthermorefelt that mechanical means, being m

Table Ill. Water qualities (a) used and (b) rejected for textileprocessing. - Raw Loose wool wool Hank TOP Package . Piece Piece I scouringdyeing dyeing scouring dyeing scouring dyeinl Samples alb 33/13 2518 1516 1517 1316 64140 46/2(-

Turbidity a - 92 - 26 95 ~ 73

(Forrnazin Units) b - 357 - 162 89 ~ 255

Color a 18 33 43 ~ 12 27 26

(" Hazen) b 67 98 33 ~ 52 46 81

a 0.70 0.26 0.50 0.1 8 0.65 - 0.30 b 0.75 1 .50 1.20 0.34 0.44 - 0.65

Manganese a 0.77 0.10 0.1 0 0.1 2 0.12 0.09 0.10 (rng/l) b 0.18 0.26 0.05 0.1 5 0.1 5 0.19 0.28

Suspended solids a - - 2 - 2 4 3 (rng/l) b - - 2 - 14 10 19

Total hardness a 41 (40) - - - 56 (601 - - (rng/l as CaCO,) b 150 (1 50) ~ 160 (1601- Alkalinity a 56 68 46 58 55 108 78 hg/l as CaCO,) b 88 90 56 223 69 107 82 -

Arnerlcan Dyestuff Reporter 30 Dyestuff Arnerlcan January Table IV. Typical analytical results.

Hum us Auxiliary Humus tank water tank bo Streamsupply effluent liquo

Sample Units 1 2 3 4

Color Hazen 30 100 60 500 Conductivity micro-mhos 1000 1100 1000 1500 Turbldlty Formarin Units 60 260 180 3000 Suspended solids msil 6 50 20 85 pH as CaCO, 7.7 7 .O 7 .O 1

Alkalinlty rngil as CaCO, 170 180 200 ~ 35 0 150 200Total Hardness mgil150 as CaCO, 350 PV rngil as CaCO, 3 20 10 60 BOD mgil as CaCO, 3 20 10 200 Chlorion mgil as CaCO, 90 160 180 200 Sulphate rngil150 as CaCO, 250 150 500 Chlorine dosage mgil as CaCO, NII NII 20 Nl:

Table V. Effects of chlorination. tra(fra cr,uld be tbcb f,~!that th.

CI pf(R.t'\< wa!er. Dose timeContact Mono-chlor- Free Di-chlor- E.Coli Total susp. (mg/l) (hr) CI. amine amine I100 mi Bact. solids

22 4 5 11 2 5 50 21 44 5 4 1 7 0 13 10 54 4 0.1 1.7 4 .O 0 9 26 54 4 0.2 2.8 3 .O 0 42 24 54 4 0.2 2.8 3 .O 0 12 16 54 4 0.2 2.8 3 .O 0 4 21 54 24 54 0 0 0 0 3 18 54 24 54 0 1 .o 4 .O 0 6 30 66 48 0 0 0 0 0 20 88 4 9 4 1 0 0 37 7.i Full-scale exper RR AQ n nr " - " 7" " U .3 u.t U 0 4 3.i large-Before 88 120 0 0 0 0 0 14 7,~ .c taken In the mil -,-, 88 120 0 0 0 0 0 JJ be solved. irres moSt Importan positive than land areas, would be essential in any full associations in theUK. Recent drought conditions;'u Workforcerea~lly andac c scale usage. A pilot-scale "Simater" continuous sand consequentrearrangements in somewater supPt, filter, passing 45.46 min of clarifiedeffluent, was make thecollection of such dataof paramOL~~~~~~v~h,"r, installed. The filter was operated for a period of two importance to the industry. months, without chemical dosing, and the results are At the time of the feasibility study, it wasdecichurdles Ind the actual f; given inTable II. It was feltthat these results were thata water with ananalysis such as the follow WE sufficient justification for proceeding to stage 1 (b). would probably be acceptable by the mill. Mill production The main criteria at all times was the suitability of therecycled water in wet processingsuch that no General analvsis significant commercial differences should be apparent Turbldity (Formazin units) in the end-product of the mill, nor should there be any Color(Hazen units) significant change in processing requirements during Fe (ma/l)-. For example, a product ion. Mn (mgil) Suspended solids (mgil) blazer Cloths Water quality requirements processing Total Hardness (mg/l) CaCO, 50 for Alkalinity (mg/l) CaC03 It is generally considered that a high quality water is Table VII. Sand fi required for the many wet processes carried out by the Table I shows that the borehole water used for; "- wool textile industry and the geographical position of processing at the mill agrees fairly well with the ab; 'low the industry is largely the result of this requirement. generalspecification except in hardness, which condl(lon Comprehensivesurveys, withanalytical details, have normallyadjusted by softening.The sewage Wo ~~% been carried out by Wira over the past decade to study effluent agreed reasonably with the general speclf': '*"I* the quality of water required for wet processing. Well tion except in turbidity, colorand suspended sOliC '"',' lr)rm over 1,000 sources of water have been analyzed for a The turbidity and in particular the color in the efflu variety of parameters and note taken of whether these are due mainly to trade effluent discharged from; "' ""'dlher wereconsidered suitable for all wetprocessing or mill, and it was thereforeconsidered that a hi4 ')" .'''.,11twr whether some form of treatment was required prior to residual color could be tolerated in water returnec use in the mill. This work on water quality with respect the mill for carrying out thesame wet processes. It ""' ','JrtJlned in to process useis part of anon-going program of also thought that a highersuspended solids figuret: M'l' ''"5talned In research, not only at Wira, but at other textile research 5 mgll suggestedabove as being acceptable io Am I$, 'rm Dyestuff 32 Arnerlcan Dyestuff Reporter - - 4 TableVI. Watt!( quality results.

/ C olor Turbiditysample Color Suspended PV Ammoniacal No. (Hazen)nitrogen (mg/l)(Formazin) pH solids (mg/l) Dye ABCABC AB C ABCAB C ABC liquor - 4250 18 155000 40 190 1 650 18 50 155.8 3.0 3.5 10.5 0.5 8 3.3 77 55 440 113 20 48 5.2 48 20 113 2 440 55 38.5 3.4 4.176 17 132 31 7 26 171 5.8 171 26 500 7 3 31 132 3.7 3.4117 41 18.6 132 72 475 142 3300142 4 475 72 132 250 18 5.3 6.5 7.2 380 17 26 17.7 4.6 5.6 1500 33 119 312 2075 17 250 7.2 5.9 16 250 4.5 17.3 4.5 250 16 5.9 7.2 250 300017 2075 5 312 119 54 223 127 19 18 216 6.7 6.685 6.7 216 18 6 19 12780 223 54 12.2 4.11.3 2.9 10718 13 7.0 215 2547 64 87 10.0 85271.2 1.38 85 7.4 7 7.5 16 5.0

~ 11 92900 46 167 8 105 39 64 210 7.44.0 7.2 104 10 15 6.4 5.7 11.0 - 163800 46 185 9 39 75 7.7 6.4 257 12 6.6 129 6.7 8 20 3.9 95 200 230 495 22 21 160 6.8 16060 21 22 49510 230 200 95 1.012.3 80 15 7.616 6.0 22.8 83 79 398 246 185 3415 20 17 190 17 20Average3415185 246 398 79 83 4.86.5 6.8 17.63.0 185.5 141 15 200 200 A Sand filter effluent 500 8 Sand filter effluent chlorinated 40 mgil NII r Dyeing effluent

[fade, could be tolerated. This view was supported by woollcottonmixture, heavy dutymelton cloths are :he fact that the stream water, at present still used as made in dark colors for use in industrial clothing such process water, oftencontains more than 5 mgll of as weatherproof jackets. suspended solids, with no apparent ill effects. Almostinvariably wetprocessing follows the same generalsequence. The woven piece leaves the loom pH Laboratory trials-Stage 1 [b] contaminated (1) with impurities which werepresent on Filtered water from the continuous sand filter was the fiber when it came into the factory, (2) with textile 7.9 used without further treatment for fairly comprehen- auxiliaries such as lubricants which were appliedto the 7.8 sive laboratory trials in which allof the wet processes at fiber in order to facilitate its conversion into yarn, and 6.5 the mill were simulated.These were a qualitative (3) with soil which has been picked up by the fiber, yarn 7.1 and cloth during its passage through the factory. The 6.6 Success and it was therefore decided to proceed directly first wet process is a washing or scouring, the purpose 7 .O with the next stage of the experiment. This involved :he use of filtered and chlorinated water as an of which is to remove allthe contaminants from the 6.5 wovenpiece. The scouring agents used at this 7 .O alternativesupply in all of the normal processes carried out at the mill. particular mill aresoap and soda and typically 22 liters 5.2 of water would be used per kg of fabric cleaned. The :.1 ! Full-scale experiments-Stage 1 [c] second wet process is that of milling the cloth by means 3.7 of acontrolled felting action. The process is carried out 7 .O Before large-scale experimentation could be under- in a rotary milling machine in which high pressure is 7 .O taken in the mill, several fundamental problems had to be solved, irrespective of technical requirements. The exerted in order to encourage localized fiber entangle- I / most importantproblem was theprotection of the ment. Fiber movement is assisted by the application of ditions and Horkforce and cooperation in experimentation. That this lubricantin the form of liquid soap which is then r supplies -s readily achieved in what is normallyavery removed by a further rinsing operation. The third and, paramount .:onservative area led in no small part to the ultimate in some senses, most critical wet process carried out at success of the work. Insurance against cloth damage the mill is that of piece dyeing. /asdecided and the actual financing of the operation were two other At thebeginning of thetrials the auxiliary water e following hl;,+!es that were successfully overcome. supply was connected to a single small sample dyeing vessel. A relativelynon-critical, navy blue, acid, Mill production leveling dye was selected from the normal production The mill is a vertical concern which manufatures a range and usedto dye a single piece of cloth which was 1oc svbstantial proportion of the blazer cloth made in finallyrinsed off using watertaken fromthe town's 25 Brltain and, within this specialized field, it produces a mains.This piece of cloth was thenreturned to the 0.' wde range of weights, qualities and colors of fabrics. normalproduction line and then to theinspection 01 For example, all-wool, light-weight crimson or lemon departmentand warehouse. No abnormalities were 5L Slazer cloths are madefor the ladies trade and detected. 50-1OC Successive pieces of clothwere processedusing 6C Table VII. Sand filtration. increasinglycritical dyestuffs and dyeing recipes Bed for we: without giving rise to complaint. At one stage, it was th the above Filtration rate throught prudent to remove residual chlorine from the s, which 15 I_..condition (m3/h) water before using it with particular dyestuffs and this :wage works was done by adding sodium thiosulphateto the water in ral specifica '.'ax. strxm 8.7 (one-bed thedye vessel. Subsequent experience, however, lded solids. '*ldX storm backwashing) 1 1 .6 showedthat, in general,residual chlorine was not I the effluen: present at a level which would cause interference with jedfrom the zri weather 3(one-bed .O the normal dyestuffs usedat this particular mill and nat a higher 'Jrv weather backwashing)4.0 de-chlorination was therefore discontinued. I In Stage 2 of themonitoring project, a series of r returned tc esses. It was &'ax. sustained in dry weather3.9 (one-bed dyestuffshave been equilibrated with chlorinated is figure thar Max sustained in dry weather backwashing) 5.2 water. It has been shown that, as might be expected, ,table to the certain dyestuffs are affected and the solution under-

' qwdn DyestuffReporter r January 1980 33 4 Table VIII. Comparison of sterilization methods. Chlorination Ozonization THE 1 Pros Cons Pros Cons Pros Cons Pros

capltal and Hlgh capltal and capltal Hlgh and 1. Low capltal running costs running costs Fairly simple Complex equipment Complex simple 2. Fairly m equipment Long contact time Short contact time contact3. Short time contact Long CATALYS required required required CHEM-MAR effect on 4. No effect turbidity Increase in due to a new dtrne, turbidity mlcellizatlon of mlcellizatlon turbidity colloidal matter CHEW-Fll 5. color Moderate Large color Polyvmyl act reductlon reduction reductlon the nonln 6. of Formatlon No harmful slde exhaustlble undeslrableeffects compounds CHEM-WI 7. of Bleaching effect No residual. Prevents se chlorine residual on Bleachlng only at polnt under-const dyelng processes of appllcation rompattble I DILEV goes a shade change.However, at practical concen- I usually of the order of 5 mgll and 4-nr permangana Products u values were in the range 7 to 12 mgll. asslstanfs ( trations,and ai thelevel of chlorinationbeing used, I synthetic flt it has been shown that there is little danger of a signifi- I anfl-agglornt cant effect gn productionshades. I Water quality monitoring retardlng agj At this stage also, mounting confidence encouraged I Throughout the mill trials the quality of the auxlh. I MACRYLI the use of theauxiliary watersupply for the final water supply was monitored before and afteruse in H. I CHEM-MAR1

rinsingoperation in place of town'swater. The ~ processing and some of the results are shown in Tat varlous acryl auxiliary water supply was then extended to half nf the VI. The figures relating to trade effluent in this tat productsart machines in the maindyehouse and in a relatively short are typical of values normally found forspent dye liqu cornblnatlon time several hundred pieces weredyed without any before dilution with rinse water. MAQUES. complaintarising. Thereafter the auxiliary water Chlorination with gaseous chlorine usually had 1' supply was extended to a secondary dyehouse in which effect of reducing color intensity by at least 50 percer i'l...rt,f.eS 01 mcludlng ti- cottonstaining is carriedout, andthen to the piece in contrast with a situation found during earlier wo' These prod scouringand milling departments.Again satisfactory when chlorination with hypochloritesolutionsometimh unwanted rnt processingproved to be possible so that towards the resulted in an increase in turbidity. k dvelng and 11 end of the mill trials pieces of cloth were leaving the At this point in the project, that atis the end of Stag MARKARI factoryhaving been scoured, milled, dyed and cotton l(c), allthe experimental work indicated that I$ The carriers stained using no water other than that taken from the quality of water being supplied to the mill for the rr provldlng sup auxiliary water supply. trial fully justified the installationof large-scale plantf and blends the Houghside worksto provide a commercial supplyl PrOperties of Analysis of liquors water. safety Table IV shows some typical chemical analyses which Discussion of thedetailed design of this plant i- MARKLUE wereobtained duringthe course of themill trials. outside the scopeof this paper beyond saying that:-- Used as dye t Various columns refer to the following samples:- tertiarytreatment plant of thedownward flow SarF- are descgned 1. Streamnear mill. Thewater is usedfor normal filtration type was selected, largely on the grounds?: marks. Also processing at the mill. economy. Sterilization of theeffluent by means) applied as a 1 2. Humustank effluent. This would normally be chlorinedosing has been installedin line with l'f MARKPEL polished by land irrigation before being discharged experiments carried out in Stage 1. to stream, and for the purposeof the trial formed the lndtcates CF The object of sterilization is to limit or totally desW Water repel feed to the sand filtration plant. thepathogenic bacteria and viruses present in IC SPECIAL, a 1 3. Treated effluent. This is the auxiliary water supply effluent. A frequently used parameter is the colifo:' MARKPEL z used in the mill trials, andis humus tank liquor after count of the samples. A sewage effluent ofappare MARKPEL s sand filtration and chlorination. clarity may contain several million coliform organisr fluorochemic 4. Exhausted dye liquor. Sample 3 after use at the mill per 100 ml.United StatesRiver and Sanita MARKSOf to be discharged to the sewer. Authorities, who frequentlyimpose limitations { Denotes a gro sewage effluent, may require a reduction to below 1; for conferrinl Chlorination per 100 ml if thereceiving stream is used and svntheti, Water pumped from theworks to the millwas treated Products are 1 recreational purposes. It is considered that a stand2 CatlonlcS with gaseous chlorine as amatter of routineand of a 100 per 100 mlwill meet all reasonat chlorineresiduals were determined at frequent requirements at Pudsey, but the view has been takj intervals. Table V shows analytical results which were thatthe plant should be designed to achieve a 1. obtained and it will be seen that, by normal standards, percent kill. This should alleviate the natural conce' very high dosagelevels in excess of 50 mgll were of mill operatives and will give scope for experiment'' required to ensure the complete absence of E coli. It with a range of chlorine dosage rates which will pro( - was thought, however, that in situations suchas theone of value inregard to futureinstallations. It is wor underinvestigation anabsolute sterility requirement noting that the existing millprocess water derived frc. would be unnecessarily stringent.Concentrations of the stream contains substantially more than 100per IL. MIDDLES ammoniacal nitrogen insamples shown in Table V were ml,containing as it does effluentfrom two othj JW 1') IJou A, 34 Amerlcan Dyestuff Reporter r January 1v sewage works. TheHoughside works atPudsey have been rk Bothchlorination andozonization were considered constructedand thebulk re-cycledwater supp Table IX. Stage forthe permanent installation but consideration of became available early in 1977. The present monitc. Table Vlll shows that chlorination should be the least ing program commenced July 1, 1977, and a consti expensive. presence has been maintained by Wira since thi A serious disadvantage of chlorine isthat undesirable date. toxiccompounds may be formed in combination with Until recently, the mill has used up to 50,000 galldl Parameter sewage effluents resulting in fish mortality in streams. merelyfor washing-off purposes, substituting P The chlorinated effluent in thiscase will be returned to recycled supply for the Beck supply. This has enat the sewage works after use, as trade effluent, when it themonitoring staff to gainvaluable experience will represent less than 10 percent of the sewage flow. sampling and analytical procedures, while building. While some build-up of chloride levels may occur this a store of results on which to base future control. will notbe critical. Thebleaching effect of residual Variable drawing rates complicate the situation a chlorine has been shown during the pilot study to be a themost important single problem to besolved is problem only at levels greater than the 1 mglI. maintain the chlorination level and work out a suitat Thefactors effectingthe efficiency of sterilization control program. This will require constant cooperati are: (a) chlorineform (free orcombined) and the between the YWA and Wira, acting in conjunctionw amount of residual:(b) contact time: (c) pH; and (d) the mill staff as regards their requirements. temperature. Theprogram of workfor theimmediate futt Chlorine combines withthe ammonia present in will consist of a series of large scale planl;: sewage effluent to form mono-chloramine and dischlor- experiments in addition to the, now, usual monitor,. amine. To achieve a freeresidual or break-point procedure. The first of these experiments has alrea chlorination, even withthe ultimate high quality been carried out and consistedof a full day'sproduct1 effluent,ahigh dosage rate is required,thereby of scouringand dyeing, inaddition to washing-c. increasingoperating costs. Combined chlorineresi- using the re-cycled water. Samples of water at 2,O. dualsare effective sterilizing agentsprovided that a gal intervals weresampled on leavingthe sewa: sufficient contact time is allowed. It has beenshown works and on entry to the mill during week-enda per" that a 100 percent kill can be achieved by a residual of 1 so thata full-day run could be carried out on mgll in combined form with a contact time of 1 hour. followingMonday. Every operation wasmonitc'; WIdesPread in To achieve this the dosage rate of up to 10 mgll was during the run and cloth (piece numbers) identificatl considered of proposed to satisfy the chlorine demand and provide maintained. Samples were taken and compared w hnCe In the exa the required residual throughout the periodof contact. normal standards. It is the intention to follow the cli orWnlsrn = as fermenting lact The monitoring and control of the chlorine dosing level through to itsfinal destination in terms of garmf at both 37" and formsaconsiderable part of the work involved in Stage production. Indole in pcptor 2 of the project. The second and subsequent experiments are to: Incapable of uti Regular micro-biological testing is an integral part of planned on similarlines. However, because of carbon; which thisstudy. The effectiveness of chlorinedeteriorates largenumber of analyticaloperations involved, 1) carbinol: and w with high pH and low temperature. The pH of 7.5 and monitoring exercise must becontrolled within theeft rod test. temperature of 15°Cwhich obtain inthis case are avaiable. While the water quality parameters will: In !he origin; favorable. The "classical" method of sterilizing such a checked inthe usualway throughoutthe en! ailendard of 1OC water is by super-chlorination followed by de-chlorina- experimentalperiod, the product monitoring will : dopled for the tion using sulphur dioxide, limited to a single day's production run perexperime' OIOlect states, It is important not to complicate processes unduly, That is, if the second experiment is scheduledovertr days, the third over three days and so on. Only Onec &brine dosag but on the other hand, it is undesirable to chlorinate at kill of E. co/. per experiment or one day per week will be followec say 8 mg I1 steady rate andnot to know what residual is Important to ac beingachieved. Furthermoredue to theretention in great detai I. Of the labor for thecontact tank, it is not possible to control the dosage Details of analysismicrobial Existing mic rate from a residual monitor at the outlet poin't. It was Pudsey finaleffluent (following sand filtrativSuppkrnented decided, therefore, to install a chlorinator, operating at PudseyBeck, and well samples, are subjected the Identificati apre-determined rate, at thepoint of entry to the analysis to bothenumerate and identify the microb Alr-borne sF contacttank. A further chlorinator is installed atthe formspresent. Methods usedinclude: w'th Cloth expo outlet,operating from aresidual monitor, to bring (a) Total colony counts on yeast extract agar (involv" Wtentlal mildc the residual to the desired level. It is anticipated that the use of solidagarlpetri dishes.taboratory tes the initial dosage rate will be regulated in such a way (b)Total bacterial counts using Standard - r water z thatthe final chlorinator can perform a "trimming" filtermembrane sets. used for dyein! function, when the complete installation is in full-scale (c) Detection of coliformbacteria and E. coli Us flnlshed c~ operation. TergitolTTCmembrane filter sets. surveys are to As an additional refinement, a residual monitor will (d)The useof selectiveculture medium (bismb lnltlal full SC; be installed at the mill to give a continuous reading of sulphite) for the detectionof pathogenic SalmoneI~a. theactual process water. Used inconjunction with The membrane filter technique is particularly USE regular bacterial count, these instruments are enabling indetermining the levels of organisms in sUPP' '*tormediate c apattern to emerge whichwill give abetter under- containing suchlow numbersthat the usual plat The range standing of the effectiveness of sterilization with aview proceduresnotdoyield meaningful results. Also, /' is to optimizing the chlorine consumption. far more important to examine a supp~yfrequently Conversion of mill to large-scale usage of recycled fairlysimple test than occasionallyby a m: &lor water: Stage 2 complicatedtest or series of Generallytests. Thefinal stage of theproject was obviously Theterm "coliform organisms" refers to gre' '"tratlOnand dependent upon the reconstruction of the Pudsey works negative,oxidose-negative, non-sporing rods capa' Occurred duri and the installation of a suitable treatment plant. This, of growingaerobically on anagar medium contal! '"Owed simila coupled with thetime required to arrangesuitable bile salts and able to ferment lactose within 48 hr at' financing of the monitoring operation. has meant that C with the productionof both acid and gas. Thegrc. Turbidityr. Some three years elapsed after the end of State 1 (c). of coliformbacteria fermenting lactoseat 30°C is fa 'A?.;( filtra,

.,"i ,380 36 American Dyestuff Reporter -1 beenre- ?r supply Table [x.Stage 2 monitoring results- means and ranges. t monitor. 3 constant Sewage works ;ince that i Sewage works afterSewage water works i after waterbefore water sand filtration IO gal / day Parameter water Beck sand filtration chlorination and sand filtration uting the ias enable Mean Range MeanMean Range Range Mean Range erience in , uilding6.65-7.70 up 7.34 6.80-7.9PH 7.30 6.95-7.8 7.307.30-7.80 7.58 ntrol. 02 Color4-1 66 20-2136 6426-1 79 0 114-309 168 Jation and Turbidity 376 33-1 279 1294 852-2820. 82-826 443 392 66-1 377 JIved is to Total sollds 606 440-807 756 500-1 180 398-1679 101 736 460-1 31 8 a suitable Suspended solids 20 1-1 49 55 38-99 9 047 8 1-38 ooperation , D,ssolved solids 59 1 41 7-787 697 460-1 120 397-1098 664 728 456-1 295 lction with Total hardness 284 170439 220 138-361 136-332 194 23 1 130-397 l permanent hardness 140 0-323 95 8-204 0-226 512 78 0-223 ate future Temporary hardness 144 69-238 137 45-183 98-284 154 155 81-193 ? planned Chloride 87 50-194 171 97434 88476 159 189 104-51 7 nonitoring Free &saline arnmonla 2 0.4-7.7 5.2 1.4-9.1 0.50.7-1 4.6 6.6 3.5-1 5 as already I Nltrate 2.9 0.144.46 3.8 0.1-7.2 2.6 0.1 -6.7 2.1 0.14.6 production 1 Nitrite 0.1 2 0.01-0.26 0.23 0.12-0.38 0.05-0.89 0.41 0.18 0.01-0.41 ashing-off, 1 COD 37 9-1 98 126 27-248 63 9-41 6 51 9-1 38 ?r at 2,000 i SOD 8.5 1-20 30 18-56 2-22 11 4.9 4.6-5.0 le sewage : end period ut onthe , aidespread incertain forms of vegetationand is not chlorination reduces turbidity still further when NH considered of any particularepidermiological impor- content is below 5 mg/dm-3. tance in the examination of waters. E. coli is a coliform organism =asdefined abovewhich is capable of Solids fermenting lactose with the production of acid and gas Beck solids vary with flow rate. Sand filtration gives at both 37” and 44°C in less than 48 hr; which produces consistentlylow suspended solids, par!icularly after indole in peptore water containing tryptophan; which is chlorination. There is a possibility of settlement in the incapable of utilizing sodium citrateas its sole source of contact tower. carbon; which is incapable of producing acetyl methyl carbinol; and which gives a positive resultin the methyl Hardness ers will be red test. Indications are that softening costs of treated water theentire ’ In the original Pudsey Project it was proposed that a will be lower than those for beck water. ng will be ! standard of 100 per 100 ml (for coliform organisms) be xperiment. adopted for the proposed industrial process water. The Chloride Treated water gives values about twice thoseof beck :d over two i project states, “Duringthe experimental period high 1ly one day chlorine dosage rates were applied resulting in 100% water.Both waters show increases duringfrosty followed n kill of E. coli inmost cases. It was considered periods, probably due to road salting. mportant to achieve such a standard if the cooperation Nitrate 9 of the labor force was to be maintained.” Existing microbial monitoring techniques were to be Beck andtreated water values are low and about filtration), . supplemented with a number of biochemical tests for equal. bjected to the identification of specific organisms. Metals 3 microbial Air-borne spore sampling techniques were coupled Cr, Fe and Cu-negligible amounts present. Mn-at with cloth exposure tests to investigate the incidence of . (involving a levelexpected inmains water. Ni, Au, Ag may be potential mildew-causing organisms at various sites. present due to thesmall plating works and a laboratory tests comparing the effects of both Leeds rd - TTC photographicworks discharging to sewers.Toxic rllains waterand Pudsey chlorinatedeffluent, when metals-traces present, but well below limits. used for dyeing and finishing, showed no difference in coli using the finished cloths’susceptibility to mildew.Mildew COD and BOD surveys are to be carried out bothprior and during Chlorination is the main factor to be watched. This 1 (bismuth Initial full scale trials at themill using re-cycled will be a problem until a steady draw on the treated nonella. effluent. water can be established. larly useful The above is a very brief, but up-to-date account of n supplies Intermediate conclusions theprogress of the“Pudsey Project.” Acomplete ualplating The rangeand means of thevarious measured account will be publishedafter June 30, 1979, on Also, it is Parameters is shown in Table IX. completion of the project. uently by a a more Color Acknowledgements Generally reduced by about halfits value duringsand So many people have been involved with this work over ; to gram- filtration and further by chlorination. Exceptions the past few years that it is impossible to mention them Ids capable occurred duringvery coldconditions. Beck water all byname. Martin Lovett,formerly Chief Pollution containing showed similar values to treated water. Officer of the, then, Yorkshire River Authority and G. 48 hr at 37” Hirst, formerly sewage works manager at Pudsey were The group Turbidity the prime movers behind the original scheme. The late 1°C is fairly Sand filtration appears to remove50-80% and [Continuedon page461

January 19% 2anuarY1980 E AmericanDyestuff Reporter 37