AU602021B2 - Water treatment compositions and processes - Google Patents

Description

2 02 This document contains the Sams. dmenis made under SSection 4 9 and is correct for printing.

COMMONWEALTH OF AUSTRALIA The Patents Act 1952-1969 0 0 0 0 0 0, 0 00 o o o 00 0 0 0 0000 0 0 o enoe o o a 0o e 0 o o0 o 0o O 00 0 00 O o o 0 0000o 0 0 o o o 0 Name of Applicant(s): Claude Mac STEWART Address of Applicant(2): Actual Inventor(X): Address for service: 345 N. Beaverdam Road, Asheville, North Carolina 28804, United States of America Claude Mac STEWART G.R. CULLEN COMPANY Dalgety House 79 Eagle Street BRISBANE QLD. 4000

AUSTRALIA.

COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: "WATER TREATMENT COMPOSITIONS AND PROCESSES" The following statement is a full description of the invention including the best method of performing it known to us: ii i ii BACKGROUND OF THE INVENTION Heretofore, compositions such as aluminum chlorhydrate, aluminum chloride and aluminum sulphate have been used in coagulating water, such as river water, or industrial discharge.

It is known that cationic polymers or aluminum compounds have been used for coagulation, and to some extent these compounds have been 10 employed together. Further, the use of clay in 0 00 oBo treating water alone or in combination with certain %000 o000 aluminum compounds is known.

S 0000 0 o 00.. Several U.S. patents disclose the use of 0000 o 00 cationic polymeric coagulants with aluminum 0°0 o 15 compounds, e.g. such as U.S. 4,559,143 to Asada et al. However, none of these patents employ aluminum chlorhydrate in their compounds.

0 o 0 000 0 00 0 00 SUMMARY OF THE INVENTION 000000 0 0 0o An object of the present invention is to 000000oooooo provide a composition and method with improved So0o ability to coagulate suspended solids in waste water 0000 00000 or turbid water.

The present invention relates to a composition for use in the coagulation of suspended solids in industrial and municipal waste water, or raw river water. The composition is essentially composed of a cationic polymer, (ii) aluminum chlorhydrate, and (iii) mica. Specifically, the composition comprises: 10-90 wt. of a cationic polymer, (ii) 10-90 wt. of a 50% aqueous solution of aluminum chlorhydrate; 2 (iii) a positive amount up to 2.0 wt. of mica.

The composition exhibits an improved capability to coagulate suspended solids in waste water.

Further, the present invention relates to a process of treating water using the composition of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The composition of the present invention comprises or consists of a cationic polymer, (ii) aluminium 0 chlorhydrate, and (iii) mica. Specifically, the composition S comprises: 1 0oo 0 0 0 0 oaa 0004 0 oo..

0000 o 0 0 0 0000 0o 0 000 0 0 0 0 0 000 0 0 0000 0 00 00 0 on 0 o0 0 0 0 0n 0 0 0 o solution) 10-90 wt. cationic polymer (ii) 10-90 wt. of a 50% aqueous solution of aluminium chlorhydrate, and (iii) a positive amount up to 2.0 wt. of mica.

When using an aluminum chlorhydrate powder (not the composition comprises: 18-95 wt. cationic polymer, (ii) 5-82 wt. aluminium chlorhydrate (dry), and (iii) a positive amount up to 4 wt. of mica.

Preferred and advantageous composition ranges are: 24-67 wt. cationic polymer, (ii) 32-75 wt. aluminum chlorhydrate solution), and (iii) 0.5-2.0 wt. mica Preferred specific compositions include: r A Composition (A) 67.0% cationic polymer 32.0% aluminum chlorhydrate solution) wet ground mica Composition (B) 50.0% cationic polymer 49.5% aluminum chlorhydrate solution) wet ground mica 0 00 0000 000 oo

S

oo0000oo 0 0 oooo 0 00 0000 0 0 0000 0000 0 0 0 oooo 0 00 o 0 oooo 00 0 0 0 0 0 ao o Composition (C) 24.0% cationic polymer 75.0% aluminum chlorhydrate (50% solution) 1.0% wet ground mica The cationic polymer employed should be water soluble. For example, the polymer can be a cationic quaternary ammonium polyelectrolyte such as poly(dimefhyldiallylammonium chloride) having the 20 formula: CH C CH 2 (CAS Registry H H No. 26062-79-3)

N

CH

3

CH

3 Cl The cationic polymer is generally a liquid 25 organic, highly cationic, polyquaternary amine, advantageously with a specific gravity 25 0 C (H 2 0 1 39.2 0 F) of 1.05-1.10.

A cationic polyamine, with a medium molecular weight, is used in order to increase the capacity of the product to neutralize charges on tl 'A_ 4 negatively charged turbidity particles and also assist in the agglomeration process of flocculation.

The polyamine selected should have the ability to readily combine with the aluminum chlorhydrate and to function effectively over a wide pH range. Suitable cationic polymers are described in the United States patents 4,053,512, RE 28,807 and RE 28,808 to Panzer. Other suitable polyamine quaternaries are disclosed in the Encyclopedia 0 0 10 of Chemical Technology, Vol. 10. 1980, pp. 501-504.

O °0 0 a 0 Suitable cationic polymers are cold jy Chemlink, 00ooo 0 o I .oo. Inc. of Plano, Texas, U.S.A. Nos. 509 and o00oo0 550-40) or Keystone Laboratories in Decatur, o Oa Alabama, U.S.A. Nos. KF-8823, 8840, 8820, 8822, 0 00 o000 15 8823, 8856), or American Cyanamide,(e.g. Nos.

577-C, 587).

Advantageously the cationic polymer is a 00 o °o0 polyquarternary polymer prepared from epichloro- 0o°o hydrin and dimethyl amine or other substituted amines. Preferred polyamines are disclosed in 0o RE 28,807 and RE 28,808 and United States patents 0 Nos. 3,894 944, 3,894,945, 3,894,946, 3,894,947, and 3,894,948.

00 0 0 0.000 The aluminum chlorhydrate is generally o0oo0o 25 used as a 50 wt. aqueous solution. The percentage of water in the solution, however, is a matter of choice (even aluminum chlorhydrate Spowder can be used). Advantageously the aluminum chlorhydrate solution has a specific gravity 60 0 F. of 1.330-1.350.

The aluminum chlorhydrate is used to cause a "polishing" effect on the treated water. The polishing property of an aluminum compound has been observed for many years and is basically due to the very high charge (cationic capacity of the Al+++ L-7

I

ion) and its ability (by hydrolysis) to form in water, multinuclear soluble hydrolysis species that are probably linear polymers.

An aluminum compound is needed which contains a high availability of aluminum, that does not have a great pH lowering effect on the treated water and yields a pH such as to readily combine with a highly charged medium molecular weight ,polyquaternary amine. Aluminum chlorhydrate fulfils each of these criteria.

0 oo Aluminum chlorhydrate has a very high 00oo00 0 oo 0 degree of available aluminum. It is this 0000

O

0 o availability (2.2 times as much as aluminum chloride Soooo and 5.6 times as much as aluminum sulfate), which o o0 o 15 makes it useful in the subject invention. It does 0 00 not appreciably lower the pH of the dosed water and it has the ability to combine with the 00 S00oo polyquaternary ammonium polymer.

0 00 0 0 00 Below is Table A, which shows jar test data S20 for the effectiveness of aluminum chlorhydrate. The ooooo00000 o o results show that a dosage of 37.5 mg./l was needed o 0 0 in order to obtain a resultant turbidity of 0.56 ooo0 NTU. TA A 0 00 TABLE

A

oooo 25 ALUMINUM CHLORHYDRATE Sample mg./l NTU 5.0 30.0 10.0 20.0 15.0 16.0 20.0 11.0 25.0 10.8 27.5 6.8 30.0 3.7 32.5 1.'8 35.0 0.83 37.5 0.56 r- lr~sautl~l )(iul-CCPI-- NOTES: Raw water is 980 ml. of city tap water with 20 ml. of a 1.0% Bentonite Clay solution added Turbidity 29 NTU.

Flash mix at 100 rpm, for 3 minutes.

Floc mix at 30 rpm, for 15 minutes.

Settling time is 15 minutes.

A suitable aluminum chlorhydrate (Enchlor) can be obtained from Courtney Industries, Inc. of o Baltimore, Maryland, U.S.A.

0 00 10 The mica of the subject invention is generally muscovite mica. Advantageously the mica o° has the formula H 2 KA1 3 (SiO 4 3 and is prepared by the °o wet grinding process. An advantageous nominal °o o, particle size is about 325 mesh and the particle shape is a very thin flake having the highest ratio 0 of surface to thickness of any inert pigment. A o a' wide variety of mesh sizes may be used.

0 bC 0° Advantageously, the mica has an apparent density (Scott Volumeter) of about 10 lbs./cu.ft, and a 20 specific gravity of 2.8-3.0.

0004cf The mica is used for the purpose of adding 00 an inert pigment in order to assist the a coagulation/flocculation process from the standpoint of presenting an extremely small "site" for the floc to build on. The mica is not electrically charged. It also aids, in a limited way, the -J process of apparent color removal. The mica does not itself coagulate the turbidity particles but only adds an available site. Below are results of "jar tests" conducted on the wet ground mica alone. As the tests indicate, an increase in dosage also increases the turbidity, thus proving that the mica adds particles and does not have any per se coagulating or flocculating properties.

I

Sample 7 TABLE B WET GROUND MICA mg./l 5.0 25.0 50.0 75.0 100.0 125.0 (1) (2) (3) (4) (6)

NTU

28.0 29.0 37.0 40.0 55.0 63.0

NOTES:

o 0 0 00 0 e 0 01 o a o o. 0 oo 0 0 0 .0 Raw water is 980 ml. of city tap water with 20 ml. of a 1.0% Bentonite Clay solution added Turbidity 28 NTU.

Flash mix at 100 rpm, for 3 minutes.

Floc mix at 30 rpm, for 15 minutes.

Settling time is 15 minutes.

a 0 O0 O 0 0 0 So o 09 0 0 S0 0 0 0 A suitable wet ground mica is alsimica which can be obtained from Franklin Minerals Products of Wilmington Massachusetts, U.S.A. Another suitable mica is ground muscovite mica which can be obtained from U.S. Mica Co., Kings Mountain, North Carolina, U.S.A.

The method of combining the three ingredients to form the composition of the subject invention is as follows: The mica should be added to the aluminum chlorhydrate (advantageously 50% aqueous solution) and mixed at a moderate speed (appro imt;m y 1000 RPM) for at least five minutes. Thereafter mixing \o RPM's should be slowed to a-pproeximaty 300ARPM's while the polymer component is slowly added to the solution. Mixing should continue for at least ten minutes. The material can then be transferred to shipping containers, i.e. drums or tankers.

r I ii

,I

i: I A Q 4 i oomuof3ltlon can comoriec. c~nci~t 17=an1:17: or or oonvit cr tr. TirCa mT V= r iz 1, -1 ;;i -1 Unless otherwise indicated, all parts and percentages are by weight.

The composition is used for the treatment of waste waters or river waters, which have a high or low suspended solids content. The treatment can be used with water from industrial processes before it is returned to the river. The composition is usefully added at the rate of from 1-100 mg./liter of water to be treated depending on water solids content. The composition effectively causes o 6 coagulation and settlement of the solids.

"Nephelometric Turbidity Unit" or NTU, is the measurement of the turbidity or "cloudiness" of a solution as determined by the use of a Nephelooo. a °oO 15 meter. This Nephelometer measures turbidity in a 0 06 o0 different manner than a standard spectrophotometer in the following way A spectrophotometer uses a o, light source, with the sample placed between it and the light "receiver" in order to measure transmito 20 tance. This is not an accurate measurement since a 00. colored liquid (even if it did not contain turbidity 0 particles) would absorb some of the light and there- °006oo fore register a decrease in transmittance. This decrease in transmittance would indicate an increase ooo0 o0 25 in turbidity. The turbidity reading would be incorrect since the colored liquid contained no "particles". A Nephelometer, on the other hand, has its light receiver placed at a 90% angle from the light source, so that it receives light which has actually been reflected off particles in the sample.

Therefore, this is a true measure of turbidity.

The United States "FEDERAL REGISTER", Vol. No.248, December,24, 1975, at Section 141.22, page 59572 and Section 141.13, page 59571 states the 9 Environmental protection Agency regulations concerning the limit of 1.0 NTU for potable water.

The following examples illustrate the invention in more detail.

EXAMPLES

For Tables 1-4, the product tested was applied to Baltimore raw water with the addition of a 1% solution of Bentonite clay. The resultant o 0 turbidity was 125 NTU and the appearance of the o 10 water was opaque to cloudy. One liter jar test o0° solutions were used on a 6-paddle Phipps and Byrd o00 gang stirrer.

0 o00 In each test the Flash mixing time (ist 0 0 a stage mixing when coagulant comes into contact with particles) was 3 minutes; the flocculation timn was 15 minutes; and the settlement time was 0 minutes. In Tables 1-4 a Hach 2100A Tubidmeter (Nephelometer) was used to determine the NTU value.

The composition of the subject invention

C

20 tested comprised: 67 wt. cationic polymer (Keystone KF-8823) (ii) 32 wt. aluminum chlorhydrate (Courtney Industries, Enchlor, 50% Solution), and 0 i (iii) 1 wt. wet ground mica (Franklin Mineral Products, Alsimica No. 12) L Sample (1) (2) (3)

NOTE:

(4) (6) (7) (8)

NOTES:

TABLE 1 INVENTIVE COMPOSITION m. NTU COMMENTS 1.0 0.91 2.0 0.91 3.0 0.91 Begin Feeding Lower Dosage 0.1 4.2 0.3 0.71 0.5 0.42 0.7 0.38 Best Dosage 0.9 0.49 Best Dosage for this composition was 0.7 mg/i with a resultant NTtJ Of 0.38 NTU 4 0t 4 4 99 099$ 041 .l9~9 99, 0600

IC

4 0 TA13LE 2 COMMERCIAL ALUMINUM CHLORHYDRATE (50% Solution as A1 2 Sample (1) (2) (3) (4) (6) 20 40 60 80 100 200

NTU

1.7 1.8 3.1

COMMENTS

NOTE: Begin Lower Dosages 00 00 (7) Too High Didn t Read Too High Didn' t Read Best Results (8) (11) (12)

NOTES:

15 16 18 15 mg./1 dosage is turbidity of 0.9 N 1.1 0.9 1.2 1.4 best at resultant Cm 11 TABLE 3 LIQUID ALUMINUM CHLORIDE (A1C1) 320 BAUME Sample mg./l NTU COMMENTS Best 55 5.6 Results NOTES: Lower and higher dosages resulted in increased turbidity supernate remained cloudy TABLE 4 LIQUID ALUMINUM SULPHATE (A1 2

SO

4 S, Sample mg. l NTU COMMENTS Best 0.I 70 5.5 Results 0 NOTES: Lower and higher dosages resulted in increased 0: 0 turbidity supernate remained cloudy 0 00 0 94 The purpose of the following tests was to evaluate the invention against other coagulants i.e.

aluminum sulfate (alum), Ultrion (a product from 0 444 o Nalco Chemical Co.) and, in some cases aluminum chloride (AlC1). Prior to each series of tests, a description of the raw water is given. The 20 inventive composition used in each case is the same as for Table 1. In the remaining tables, a Hach 000 oooo ratio Nephelometer (turbidmeter) was used. The water treated was Swannanoa River (Ashville, N.C.) water raw water turbidity equals 47 NTU TABLE Inventive Composition Sample mg./l NTU 3.0 5.00 4.0 1.16 5.0 0.47 j:.

TABLE 6

ULTRION

Sample (1) (2) (3) Mng. 40.0 50.0 70.0

NTU

7.,60 4.90 0. TABLE 7 ALUMINUM SULFATE Sample (1) (2) (3) 40.0 75.0 100.0

NTU

5.30 2,00 0.52 C C C 4CCC ago C

CCCI

a I I CC C 150CC a @0CC o q& 00 C 15 CC The next series of tests used city tap water (980 ml.) wit~h 20 ml. of a 15 Bentonite Clay solution added, The turbidity of this solution was 29 NTU. The inventive composition used (Table 8) is the same as that for Tables 1 and TABLE 8 Inventive Composition

COIC

C 15

CIII

CICCIC

a 15 Sample (1) (2) (3) (4) (5) (6) Mg. /1 1.0 2.0 3.0 4.0 5.0 6.0

NTU

9. 0.63 0.16 0.24 0.26 9.50 TABLE 9

ULTRION

Sample (1) (2) (3) (4) (6) 45.0 50.0 55.0 60.0 65.,0 70.0

NTU

14.60 10.90 06.50 01.50 00.40 00.60 0 0 0 C~ 0~0. t~ 0 C9 0 i- X- _li -LI1_ lll~-~ a TABLE ALUMINUM SULFATE Sample (1) (2) (3) (4) (6) mg. /l 57.0 60.0 66.0 84.0 87.0 90.0

NTU

7.30 1.50 0.78 0.67 0.62 0.58 U a S t Tables 11 through 18 show the superiority of the inventive composition over other coagulants in treating (coagulating/flocculating) water with an extremely high and low pH. An acid solution was used to decrease the raw water pH and a sodium hydroxide solution was used to increase the pH. In all cases the raw water consisted of 980 ml. tap water with 20 ml. of a 1.0% bentonite clay solution added. The Riverclear composition used (Tables 11 and 15) was the same as that used in Tables 1-5 and 8.

TABLE 11 Inventive Composition Coo as, o 25 0*00 0 06 Sample (1) (2) (3) (4) (6) pH 8.0 7.5 7.0 10.4 10.0 9.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0

NTU

1.66 0.92 0.38 1.42 0.86 0.59 TABLE 12

ULTRION

Sample (1) (2) (3) (4) (6) pH 7.7 8.0 8.5 9.0 9.5 10.0 mg 45.0 45.0 45.0 45.0 45.0 45.0

VTU

0.24 0.20 0.26 0.39 0.83 1.91

I

TABLE 13 ALUMINUIM SULFATE Sample (1) (2) (3) (4) (6) pH! 7.5 8.0 8.5 9.0 9.5 10.5 34.0/ 34.0 34.0 34.0 34.0 34.0

NTU

3.3 1.45 1.82 2.70 26.0 28.*0 TABLE 14 ALUMINUM CHLORIDE t If 0 9, 0 c a a, 00 00 o 0 00 00 a a Sample (2) (3) (4) (5) (6) pH! 7 .5 8.0 8.5 9.0 9.4 10.0 Mg ./l 25.0 25.0 25.0 25.0 25.0 25.0

NTU

0.47 0.36 3.40 17 19.80 19.90 TABLE Inventive Composition Sample (1) (2) (3) (4) (5) (6)

PH!

5.3 5 .1' 4.8 3.6 3.7 3.5 mg./i 4.0 4.0 4.0 4.0 4.0

NTU

0.69 0.68 0 .86 0.88 0.56 TABLE 16

ULTRION

Sample 1) (2) (3) (4) (6) pH! 6.5 6.0 5.1 4.1 3.1 2.9 4 .0 45.0 45.0 45.0 45.0 45.0

NTU

0.28 0.32 0.39 0.47 0.97 1.*31 TABLE 17 ALUMINUM SULFATE Sample (1) (2) (3) (4) (6) pH 3.0 2.8 3.2 3.5 3.8 3.7 mg./I 34.0 34.0 34.0 34.0 34.0 34.0

NTU

0.47 0.73 0.67 0.39 0.35 0.45 TABLE 18 ALUMINUM CHLORIDE o oo 00 0 0 00 000 0 0 0oo 00000 cooo 0 00 Soo0 0000 0 0 o a 0900 0 o o000 0 0 0000 a 0 Sample (1) (2) (3) (4) (5) (6)

EPH

6.5 6.0 5.0 3.9 3.1 2.9 mg./I 25.0 25.0 25.0 25.0 25.0 25.0

NTU

0.37 0.35 0.44 0.48 0.93 1.81 Tables 19 and 20 show results for the 20 above-described Composition and in the treatment of raw Swannanoa River water consisting of 980 ml. tap water with 20 ml. of a 1% bentonite clay solution added. The particular components used in these tables are the same as the above tables.

.25 TABLE 19 COMPOSITION (B) Sample (1) (2) (3) (4) (6) (7) (8) (9) mg./l 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0

NTU

18.30 14.30 2.20 0.34 0.28 0.20 0.30 0.35 0.96 1.22 -j 4j L Ji TABLE COMPOSITION (C) Sample mg./l NTU 10.0 19.00 15.0 12.00 20.0 3.30 21.0 2.30 22.0 0.50 23.0 0.29 24.0 0.30 25.0 0.51 30.0 0.25 It is quite evident from the above data that the inventive compositions are superior to the other major coagulants in all areas of significant Cott' coagulation chemistry on natural river waters or ii' similar influent flows. Some of these benefits are: 1. Decrease in coagulant dosage to attain Sacceptable turbidity levels.

2. The ability of the inventive compositions to coagulate efficiently in waters of fairly neutral pH and in waters of pH extremes.

3. Decrease the sludge volume generated.

4. Produce a sludge of superior quality so that drying times for the sludge will be decreased.

While the present invention has been illustrated by detailed descriptions of preferred embodiments, it will be obvious to those skilled in ~iunr- l u lrrx il'i i a at 0 0 t 00 ooo: 000t 0000 9 0 t 0 00 0 0t 0* 0 0 0P 0 01

C

C 00 17 the art that various changes in form and detailed can be made therein without departing from the true scope of the invention. For that reason, the invention must be measured by the claims appended hereto and not by the foregoing preferred embodiments.

i i i I f L

Claims (5)

1. A composition for the treatment of water containing suspended solids comprising the combination of: a cationic polymer, aluminum chlorhydrate, and mica.

2. A composition as in claim 1, comprising:

10-90 wt. cationic polymer; 10-90 wt. of a 50 wt. aqueous solution of aluminum chlorhydrate; and o0r a positive amount up to 2 wt. wet ground o @1 mica. o0@ °00 3. A composition as in claim 1 comprising: 0069

18-95 wt. cationic polymer, *t 0 Ct (ii) 5-82 wt. aluminium chlorhydrate, and (iii) a positive amount up to 4 wt. mica. 4. A composition as in any preceding claim comprising:

24-67 wt. cationic polymer, 0 It (ii) 32-75 wt. of a 50% aqueous solution of aluminum chlorhydrate, and (iii) 0.5-2 wt. mica. o 5. A composition as in any preceding claim, wherein 0 0 ,J °o said cationic polymer is a water soluble quaternary ammonium polyelectrolyte. 6. A composition as in any preceding claim, wherein said mica has the formula H KA1(Si0 7. A method of treating water containing suspended 19 solids to remove the solids therefrom comprising the steps of: introducing into said water the combination of the agents a cationic polymer, (II) aluminum chlorhydrate, and (III) mica, to coagulate said solids in said water, and removing the coagulated solids from the treated water. 8. A method as in claim 7 wherein the introducing step comprises the step of introducing the combination comprising 10-90 wt. cationifc polymer; 10-90 wt. of a 50 wt. ct aqueous solution qf aluminum chlorhydrate; and a positive amount up to 2 wt. wet ground mica. 9. A method as in claims 7 or 8 wherein said combination is introduced as a formulated combined composition. A method as in claim 7, 8, or 9 wherein the introducing step comprises introducing 1-100 mg total weight of said combination per liter of said water. 1 t t 11. A method as in claim 7, 8, 9, or 10 wherein said cationic polymer is a water soluble quaternary ammonium polyelectrolyte. I 12. A method as in claim 7, 8, 9, 10 or 11 wherein said wet ground mica has the formula H KA (Si0) 3. 13. A method of formulating a combination composition for the treatment of water containing suspended solids said method comprising the steps of: adding mica to aluminum chlorhydrate; S 1 'AL I 4 mixing the mica and the aluminum chlorhydrate; adding a cationic polymer while continuing mixing to form said composition; and recovering said combination composition. 14. A method as in claim 13 wherein step comprises the step of mixing at a speed of 1000 300 RPM for at least minutes. A method as in claim 13 or 14 wherein step (c) comprises the step of adding cationic polymer while mixing at oo00 a speed of 300 100 RPM, and continuing mixing at a speed of 0 0 a0f 00oo0 300 100 RPM for at least 10 minutes. ooo0 0° 4 16. A method as in claim 13, 14 or 15 wherein the 0000 0 components are added in the following amounts; 0 o" 10-90 wt. cationic polymer 10-90 wt. of 50 wt. aqueous solution of aluminum chlorhydrate; and 0 0 o00o a positive amount up to 2.0 wt. wet ground mica. o 4 0 00 0 0 0 17. A method as in claim 13, 14, 15 or 16 wherein said oo. cationic polymer is a water soluble quaternary ammonium polyelectrolyte. 18. A method as in claim 13, 14, 15, 16 or 17 wherein a said wet ground mica has the formula H2KA 3 (Si0 4 3 19. A composition for the treatment of water substantially as hereinbefore described with reference to the examples containing: a cationic polymer .'0 v 21 aluminum chiorhydrate; and mica. DATED this 18th day of July 1990 CLAUDE MAC STEWART By his Patent Attorneys CULLEN CO. a 00 0 0 0 00000 0000 O00 00 a 000 9 t r