GB2032905A - Detoxification of Cationic Flocculants - Google Patents
Detoxification of Cationic Flocculants Download PDFInfo
- Publication number
- GB2032905A GB2032905A GB7936350A GB7936350A GB2032905A GB 2032905 A GB2032905 A GB 2032905A GB 7936350 A GB7936350 A GB 7936350A GB 7936350 A GB7936350 A GB 7936350A GB 2032905 A GB2032905 A GB 2032905A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ppm
- salt
- sodium
- flocculant
- anionic polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 125000002091 cationic group Chemical group 0.000 title claims abstract description 17
- 239000008394 flocculating agent Substances 0.000 title abstract description 11
- 238000001784 detoxification Methods 0.000 title description 3
- 229920006318 anionic polymer Polymers 0.000 claims abstract description 8
- 150000003839 salts Chemical class 0.000 claims abstract description 8
- 150000007524 organic acids Chemical class 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 229920001495 poly(sodium acrylate) polymer Polymers 0.000 claims description 5
- NNMHYFLPFNGQFZ-UHFFFAOYSA-M sodium polyacrylate Chemical group [Na+].[O-]C(=O)C=C NNMHYFLPFNGQFZ-UHFFFAOYSA-M 0.000 claims description 5
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 4
- 125000000129 anionic group Chemical group 0.000 claims description 4
- 229920000371 poly(diallyldimethylammonium chloride) polymer Polymers 0.000 claims description 4
- 229920000768 polyamine Polymers 0.000 claims description 4
- 229920000193 polymethacrylate Polymers 0.000 claims description 4
- 229910052708 sodium Inorganic materials 0.000 claims description 4
- 239000011734 sodium Substances 0.000 claims description 4
- CDOUZKKFHVEKRI-UHFFFAOYSA-N 3-bromo-n-[(prop-2-enoylamino)methyl]propanamide Chemical group BrCCC(=O)NCNC(=O)C=C CDOUZKKFHVEKRI-UHFFFAOYSA-N 0.000 claims description 3
- 150000004996 alkyl benzenes Chemical class 0.000 claims description 3
- 235000019329 dioctyl sodium sulphosuccinate Nutrition 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 229920005552 sodium lignosulfonate Polymers 0.000 claims description 3
- 229940092714 benzenesulfonic acid Drugs 0.000 claims description 2
- JJWLVOIRVHMVIS-UHFFFAOYSA-N isopropylamine Chemical group CC(C)N JJWLVOIRVHMVIS-UHFFFAOYSA-N 0.000 claims description 2
- 231100001231 less toxic Toxicity 0.000 claims description 2
- 238000009877 rendering Methods 0.000 claims description 2
- 231100000331 toxic Toxicity 0.000 abstract description 7
- 230000002588 toxic effect Effects 0.000 abstract description 7
- 231100000419 toxicity Toxicity 0.000 abstract description 6
- 230000001988 toxicity Effects 0.000 abstract description 6
- 239000003643 water by type Substances 0.000 abstract description 6
- 238000005352 clarification Methods 0.000 abstract 1
- 235000005985 organic acids Nutrition 0.000 abstract 1
- 241000251468 Actinopterygii Species 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 150000001412 amines Chemical group 0.000 description 6
- ZKHQWZAMYRWXGA-KQYNXXCUSA-J ATP(4-) Chemical compound C1=NC=2C(N)=NC=NC=2N1[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OP([O-])([O-])=O)[C@@H](O)[C@H]1O ZKHQWZAMYRWXGA-KQYNXXCUSA-J 0.000 description 4
- ZKHQWZAMYRWXGA-UHFFFAOYSA-N Adenosine triphosphate Natural products C1=NC=2C(N)=NC=NC=2N1C1OC(COP(O)(=O)OP(O)(=O)OP(O)(O)=O)C(O)C1O ZKHQWZAMYRWXGA-UHFFFAOYSA-N 0.000 description 4
- 241000277275 Oncorhynchus mykiss Species 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000002351 wastewater Substances 0.000 description 4
- 238000004166 bioassay Methods 0.000 description 3
- 241000894006 Bacteria Species 0.000 description 2
- 230000007059 acute toxicity Effects 0.000 description 2
- 231100000403 acute toxicity Toxicity 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000001580 bacterial effect Effects 0.000 description 2
- -1 e.g. Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- 238000006386 neutralization reaction Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 231100000582 ATP assay Toxicity 0.000 description 1
- 229920001817 Agar Polymers 0.000 description 1
- 239000002028 Biomass Substances 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 description 1
- BRLQWZUYTZBJKN-UHFFFAOYSA-N Epichlorohydrin Chemical compound ClCC1CO1 BRLQWZUYTZBJKN-UHFFFAOYSA-N 0.000 description 1
- ULUAUXLGCMPNKK-UHFFFAOYSA-N Sulfobutanedioic acid Chemical class OC(=O)CC(C(O)=O)S(O)(=O)=O ULUAUXLGCMPNKK-UHFFFAOYSA-N 0.000 description 1
- TTWYZDPBDWHJOR-IDIVVRGQSA-L adenosine triphosphate disodium Chemical compound [Na+].[Na+].C1=NC=2C(N)=NC=NC=2N1[C@@H]1O[C@H](COP(O)(=O)OP(O)(=O)OP([O-])([O-])=O)[C@@H](O)[C@H]1O TTWYZDPBDWHJOR-IDIVVRGQSA-L 0.000 description 1
- 239000008272 agar Substances 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 125000004177 diethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 239000002054 inoculum Substances 0.000 description 1
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- GOLXNESZZPUPJE-UHFFFAOYSA-N spiromesifen Chemical compound CC1=CC(C)=CC(C)=C1C(C(O1)=O)=C(OC(=O)CC(C)(C)C)C11CCCC1 GOLXNESZZPUPJE-UHFFFAOYSA-N 0.000 description 1
- 150000003460 sulfonic acids Chemical class 0.000 description 1
- 239000012085 test solution Substances 0.000 description 1
- 231100000820 toxicity test Toxicity 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Removal Of Specific Substances (AREA)
Abstract
Waters which have been treated with polymeric cationic flocculants for settling and clarification and which contain residual amounts of such flocculants which are toxic, are treated with anionic polymers or salts of organic acids to remove this toxicity.
Description
SPECIFICATION
Detoxification of Cationic Flocculants
This invention relates to the detoxification of cationic flocculants.
Waste waters, e.g. "red waters" from iron-ore mining operations, must eventually be disposed of.
and in the past this was done by discharging the effluent into the nearest stream or lake, with consequent pollution problems. However, statutes in most communities now forbid discharge of untreated waste waters in this way. Treatment of the water is generally with flocculants of various kinds, the purpose being to remove the red iron oxide particles which visibly cause discoloration after discharge into streams. Particularly efficient flocculants for red water are the polymeric cationic flocculants. However, such cationics are acutely toxic to fish and even the rather small amounts left in the waste water after settling present toxicity problems when the treated waters are discharged. The aim of the present invention is to reduce or eliminate such toxic after-effects.
According to the present invention there is provided a method of rendering polymeric cationic flocculant-treated water less toxic which comprises adding thereto an anionic polymer or a salt of an organic acid, or a mixture thereof. Thus, a specified anionic material is mixed with the waters, e.g., waste waters, which have been treated with a polymeric cationic flocculant and which are otherwise ready for discharge into local fresh waters.
The present invention is operable with polymeric cationic flocculants generally; thus substantially all waters which have been treated with polymeric cationic flocculants and which have residual toxicity because of such treatment, may be treated with the specified anionic material thereby either to remove such toxicity altogether or to reduce it to acceptable levels.
Among the polymeric cationic flocculants that leave toxic residues treatable by the process of this invention are the following:
polydiallyldimethylammonium chloride, available commercially from American Cyanamid Co.
as "Magnifloc" 589C or from Calgon Co. as "M502".
polyquaternary amines, molecular weight 50,000-80,000, for example those made by the processes described in U.S. Patent No. 3,738,945, including that available commercially from
American Cyanamid Co. as "Magnifloc" 573G and 577C.
These polyquaternaries generally have the formula
where R1 and R2 are independently methyl or ethyl, X is Cl, Br, or I, and n is 3 to 10,000, preferably 5 to
1000; they can be made by reacting dimethyl (or diethyl) amine with epichlorohydrin.
The following anionic polymers are typically used in the present invention: sodium polyacrylate, generally with a molecular weight from 1000 to 250,000, typically about 100,000, and sodium polymethacrylate, generally with a molecular weight from 1000 to 1 5,000, typically about 4500.
The organic acid salts used are generally salts of sulfonic acids or sulfosuccinic acid, specific
examples being the isopropylamine salt of alkyl benzene sulfonic acid, sodium lignosulfonate, and
dioctyl sodium sulfosuccinate.
Effluents containing, say, 0.1 to 1000 ppm of cationic flocculant residue can generally be treated
in accordance with this invention. The treatment typically uses 0.2 to 5, preferably 0.7 to 2, parts of
anionic material per part of residual cationic flocculant.
The following Examples further illustrate the present invention.
Example 1
Red water which had been treated with polydiallyldimethylammonium chloride flocculant gave a
clear effluent which, however, still contained 6 ppm flocculant. The effluent was found to be toxic to
fish. Toxicity tests were carried out using 10 rainbow trout fingerlings in the effluent. In both runs all 10
fish were killed within 100 hours. Seven ppm of sodium polyacrylate (mol wt, about 100,000) was
added to the toxic effluent, and this liquid was tested for toxicity against 10 rainbow trout fingerlings.
All received two replicates of the test (96 hours). All fish were alive at the end of the tests.
Example 2
Example 1 was repeated except that the flocculant was a cationic polyamine (prepared in
accordance with U.S. Patent 3,738,945). The effluent contained six ppm (about 3 ppm high molecular weight-about 50,000, and 3 ppm low molecular weight-about 4500) of flocculant and killed all 1 0 fish in 4 hours. Application of the sodium polyacrylate at 27 ppm eliminated the toxicity of the cationic polyamine.
Bioassay Methods
The bioassays consisted of simple pass-fail procedures in which rainbow trout fingerlings were exposed to full-strength test solutions for 96 hours. The test indicates whether acute toxicity is present or absent in the sample. Controlled test parameters and monitoring procedures for bioassays were based on the Canadian Federal Government Guidelines for Measurement of Acute Toxicity in the
Mining Industry and methods described by A.S.T.M. 1 971. In brief, certified "disease-free" rainbow trout fingerlings were used. Tests were conducted in duplicate, where possible, and fish tank stocking ratios averaged 2.2 litres per gram of fish. Dissolved oxygen levels were maintained above 8 mg/l and pH values ranged between 6.6 and 8.7.Mortality in the test tanks was recorded after 1/4, 1/2, 1, 2, 4, 8, 24, 48, 72 and 96 hours of exposure. Similarly pH, dissolved oxygen and temperature were
monitored at 0, 4, 8, 24, 48, 72 and 96 hours.
Example 3
A series of experiments were made to determine the effect of the invention on certain commonly encountered bacteria.
A culture isolated from a sludge sample from a cooling water system was used as a test medium.
Cultures were prepared by spreading an inoculum of the organism over an agar plate, followed by incubation overnight at 370C. This yielded a lawn of bacteria which was washed from the plate into 20 ml of sterilized deionized water.
100 ml of 50 ppm of polyquaternary amine (Magnifloc 573C. above) was added to a sterile
plastic bag, and to this was added a known concentration of material to be tested as detoxicant. To this
mixture was added 1 ml of stock bacterial solution and the bag was shaken and incubated for one hour
at room temperature. Then the living biomass was measured by performing an ATP (adenosine
triphosphate) assay. It had been shown in previous experiments that the viable bacterial population
was significantly reduced after this treatment with 50 ppm of polyquaternary amine alone, and this
was confirmed in the first experiment of this series.Several experiments were carried out and a
neutralization index (NI) was calculated according to:
ATP in treated sample NI x100
ATP in control
Thus a neutralization index of 100 means complete removal of the toxic effect of the polyquaternary amine. The experimental results are given in Tables 1-5. (There was a slight variation in procedure for generating the results in Table 3, in that the sample was stored at 40C for three days before the ATP assay was performed-this had been shown by earlier work to be a valid procedure).
In the Tables the following code is used.
I=Polyquaternary amine (e.g., Magnifloc 573C) lI=Sodium polymethacrylate, M.W. 4500 lli=lsopropylamine salt of alkylbenzene sulfonic acid
IV=Dioctyl sodium sulfosuccinate
V=Sodium lignosulfonate.
Table 1
A TP ngllml Treatment (after 1 hr) NI
50 ppm 1+300 ppm 11 66 93
50 ppm 1+75 ppm lil 26 37
50 ppm 1+75 ppm IV 4.1 5.8 50 ppm 1+170 ppm V 3.5 4.9
50 ppm 1 0.23 0.3
No treatment (Control) 71 1Nanograms.
Table 2 A TP nglml Treatment (after 1 hr) Nl 50 ppm 1+100 ppm 11 46 90
50 ppm 1+200 ppm 11 50 98
50 ppm 1+300 ppm 11 48 94
50 ppm 1+400 ppm 11 46 90
50 ppm 1+500 ppm 11 46 90
50 ppm 1+200 ppm 111 43 84
No treatment (Control) 51
Table 3
ATP nglml Treatment (after 1 hr) Nl 50 ppm 1+ 10 ppm 11 0.59 1.8
50 ppm 1+50 ppm 11 0.29 0.9
50 ppm 1+75 ppm 11 23 72
50 ppm 1+300 ppm 111 37 116
50 ppm 1+250 ppm V 20 63
No treatment (Control) 32
Table 4
ATP nglml Treatment (after 1 hrJ Nl 50 ppm 1+250 ppm IV 36 71
50 ppm 1+500 ppm V 72 141
No treatment (Control) 51
Table 5 A TP nglml Treatment (after 1 hr) Nl (i) 100 ppm 1+50 ppm 11 0.52 1.0
(ii) 100 ppm 1+100 ppm 11 0.68 1.3
(iii) 100 ppm 1+200ppm 11 37 74
(iv) 100 ppm 1+300 ppm 11 45 90
(v) 100 ppm 1+400 ppm 11 36 72
(vi) 200 ppm 1+100ppm 11 < 0.2 < 0.4
(vii) 200 ppm 1+200 ppm 11 < 0.2 < 0.4
(viii) 200 ppm 1+300 ppm 11 6.6 13
(ix) 200 ppm 1+400 ppm 11 52 100
(x) 200 ppm 1+500 ppm íl 57 100
(xi) No treatment (Control) 50
These results show that 50 ppm of I can be effectively detoxified using 100 ppm or more of II, 200-300 ppm of Ill, and 500 ppm of V. Table 5 shows that an increased level of I requires a proportionately higher dose of II.
Claims (12)
1. A method of rendering polymeric cationic flocculant-treated water less toxic which comprises adding thereto an anionic polymer or a salt of an organic acid, or a mixture thereof.
2. A method according to Claim 1, in which the said salt is an isopropylamine salt of alkyl benzene sulfonic acid.
3. A method according to Claim 1, in which the said salt is sodium lignosulfonate.
4. A method according to Claim 1, in which the said salt is dioctyl sodium sulfosuccinate.
5. A method according to Claim 1, in which the said anionic polymer is sodium polyacrylate or sodium polymethacrylate.
6. A method according to any one of Claims 1 to 5, in which the cationic flocculant is polydiallyldimethylammonium chloride or a polyamine.
7. A method according to Claims 5 and 6, in which the flocculant is polydiallyldimethylammonium chloride and the anionic polymer is sodium polyacrylate.
8. A method according to Claims 5 and 6, in which the flocculant is a polyamine and the anionic polymer is sodium polymethacrylate.
9. A method according to any one of Claims 1 and 5 to 8, in which the anionic polymer is added to provide an anionic polymerflocculant weight ratio of 0.2 to 5:1.
10. A method according to Claim 9, in which the said ratio is 0.7 to 2:1.
11. A method according to Claim 1 substantially as described in any one of Examples 1 to 3.
12. Water whenever treated by a method as claimed in any one of the preceding claims.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000313928A CA1116324A (en) | 1978-10-23 | 1978-10-23 | Detoxification of cationic flocculants |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2032905A true GB2032905A (en) | 1980-05-14 |
| GB2032905B GB2032905B (en) | 1983-01-06 |
Family
ID=4112664
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7936350A Expired GB2032905B (en) | 1978-10-23 | 1979-10-19 | Detoxification of cationic flocculants |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS55104691A (en) |
| CA (1) | CA1116324A (en) |
| DE (1) | DE2942111A1 (en) |
| ES (1) | ES485286A0 (en) |
| FR (1) | FR2439748A1 (en) |
| GB (1) | GB2032905B (en) |
| IT (1) | IT1125552B (en) |
| SE (1) | SE7908732L (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58216575A (en) * | 1983-04-20 | 1983-12-16 | 鹿島建設株式会社 | Storage device for powdered and granular body |
| GB9507895D0 (en) * | 1995-04-18 | 1995-05-31 | Allied Colloids Ltd | Aqueous purification processes |
| US6620330B2 (en) * | 2001-12-18 | 2003-09-16 | Baker Hughes Incorporated | Detoxification of quaternary onium compounds with polycarboxylate-containing compound |
| CN104925929B (en) * | 2015-05-19 | 2016-12-07 | 河南正佳能源环保股份有限公司 | A kind of composite flocculation agent for treatment of dyeing wastewater |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1179098B (en) * | 1961-05-03 | 1964-10-01 | Basf Ag | Flotation agent for clarifying waste water containing paper fibers |
| NL282787A (en) * | 1961-09-05 | 1900-01-01 | ||
| US3377274A (en) * | 1965-01-05 | 1968-04-09 | Nalco Chemical Co | Method of coagulation of low turbidity water |
| DE2451776A1 (en) * | 1973-11-08 | 1975-05-15 | Ciba Geigy Ag | Removal of cationic substances from effluent - using a suitably treated cellulose material opt. contg. active carbon |
-
1978
- 1978-10-23 CA CA000313928A patent/CA1116324A/en not_active Expired
-
1979
- 1979-10-18 DE DE19792942111 patent/DE2942111A1/en not_active Withdrawn
- 1979-10-19 GB GB7936350A patent/GB2032905B/en not_active Expired
- 1979-10-22 SE SE7908732A patent/SE7908732L/en not_active Application Discontinuation
- 1979-10-22 IT IT26697/79A patent/IT1125552B/en active
- 1979-10-22 JP JP13534679A patent/JPS55104691A/en active Pending
- 1979-10-23 ES ES485286A patent/ES485286A0/en active Granted
- 1979-10-23 FR FR7926292A patent/FR2439748A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| GB2032905B (en) | 1983-01-06 |
| JPS55104691A (en) | 1980-08-11 |
| DE2942111A1 (en) | 1980-04-30 |
| ES8100226A1 (en) | 1980-11-01 |
| ES485286A0 (en) | 1980-11-01 |
| FR2439748A1 (en) | 1980-05-23 |
| IT1125552B (en) | 1986-05-14 |
| IT7926697A0 (en) | 1979-10-22 |
| FR2439748B1 (en) | 1984-04-20 |
| SE7908732L (en) | 1980-04-24 |
| CA1116324A (en) | 1982-01-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |