GB2113199A - Detoxication of industrial waste - Google Patents
Detoxication of industrial waste Download PDFInfo
- Publication number
- GB2113199A GB2113199A GB08300987A GB8300987A GB2113199A GB 2113199 A GB2113199 A GB 2113199A GB 08300987 A GB08300987 A GB 08300987A GB 8300987 A GB8300987 A GB 8300987A GB 2113199 A GB2113199 A GB 2113199A
- Authority
- GB
- United Kingdom
- Prior art keywords
- slurry
- acid
- process according
- heavy metal
- salts
- 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
- 239000002440 industrial waste Substances 0.000 title description 4
- 239000002002 slurry Substances 0.000 claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 20
- 150000003839 salts Chemical class 0.000 claims abstract description 20
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 17
- 239000002253 acid Substances 0.000 claims abstract description 16
- 239000000725 suspension Substances 0.000 claims abstract description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000001117 sulphuric acid Substances 0.000 claims abstract description 11
- 235000011149 sulphuric acid Nutrition 0.000 claims abstract description 11
- 239000000203 mixture Substances 0.000 claims abstract description 9
- 239000002699 waste material Substances 0.000 claims abstract description 9
- 239000011368 organic material Substances 0.000 claims abstract description 6
- 239000011343 solid material Substances 0.000 claims abstract description 5
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 4
- 229910052751 metal Inorganic materials 0.000 claims abstract description 4
- 239000002184 metal Substances 0.000 claims abstract description 4
- 239000011707 mineral Substances 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 238000005406 washing Methods 0.000 claims description 7
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 5
- 239000000920 calcium hydroxide Substances 0.000 claims description 5
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 5
- 235000011116 calcium hydroxide Nutrition 0.000 claims description 5
- 238000010306 acid treatment Methods 0.000 claims description 3
- 229910021645 metal ion Inorganic materials 0.000 claims description 3
- 235000010755 mineral Nutrition 0.000 claims description 3
- 230000003472 neutralizing effect Effects 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 238000000605 extraction Methods 0.000 claims 2
- 238000002360 preparation method Methods 0.000 claims 1
- 239000010985 leather Substances 0.000 abstract description 5
- 239000007788 liquid Substances 0.000 abstract 1
- 229910001430 chromium ion Inorganic materials 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 4
- 231100000331 toxic Toxicity 0.000 description 4
- 230000002588 toxic effect Effects 0.000 description 4
- 230000008030 elimination Effects 0.000 description 3
- 238000003379 elimination reaction Methods 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- WLZRMCYVCSSEQC-UHFFFAOYSA-N cadmium(2+) Chemical compound [Cd+2] WLZRMCYVCSSEQC-UHFFFAOYSA-N 0.000 description 1
- 229910001424 calcium ion Inorganic materials 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000008394 flocculating agent Substances 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 229910021432 inorganic complex Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000012716 precipitator Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 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
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- 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
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
- C02F1/5245—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
-
- 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
- C02F1/529—Processes or devices for preparing lime water
-
- 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
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/004—Sludge detoxification
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/20—Heavy metals or heavy metal compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
- C02F2101/303—Complexing agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/22—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof
- C02F2103/24—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof from tanneries
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Treatment Of Sludge (AREA)
- Removal Of Specific Substances (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
A process for the detoxication of waste slurries, in particular from the leather and skin industry, containing heavy metal salt complexes and organic materials comprises treating a suspension containing at most 100 kg/m<3> of solid material with sulphuric acid and/or a mineral acid mixture composed of at least 30% by weight of sulphuric acid. The acid liquid containing the heavy metal salts is separated from the slurry, and the solution is neutralized; the metal salts are precipitated, purified and the organic slurry is washed to make it metal ion- and acid-free.
Description
SPECIFICATION
Detoxication of industrial waste
The invention relates to a process for the detoxication of industrial waste matter. More particularly, the invention concerns a process for the elimination of the toxic heavy metal salt complexes for industrial wastes, in particular slurries formed in the leather and skin industry.
The tanning and currying of hides leads to the formation of a slurry containing about 80 to 95% of water. Due to its high organic material content this slurry could advantageously be used as a fertilizer, if it were not contaminated with highly toxic heavy metal ions, frequently chromium ions, contained in the chemicals used in leather manufacturing.
Burning of the slurry, because of the high amount of water present, is uneconomic. There are numerous methods known in the art by which the colloidal organic materials can be condensed by adding suitable flocculating agents to improve their filterability, which, however, fail to solve the problem of economic elimination of water.
Slurries having a high water content are generally stored in lakes, but due to the more and more severe requirements of environmental protection the selection of a suitable place for deposition is increasingly difficult.
As to the elimination of the toxic materials and utilization of the valuable components of waste slurries there is neither teaching nor any hint in the prior art.
The invention relates to a process by which heavy metal salts, in particular chromium, can be eliminated from waste slurries and a residue containing organic materials complying with the requirements of the encironmental protection is obtained, which can then be utilized in agriculture. The invention is based on the recognition that the heavy metals compunds which are present as various organic or inorganic complexes or a precipitate insoluble in water can be decomposed by mineral acids and eliminated from the slurry in a waste-soluble form.
According to the invention, we propose a process for the detoxication of waste containing one or more heavy metal salt complexes comprising homogenising a slurry of waste with water to give a suspension of the solid material having a maximum concentration of 100 kg/m3, adding sulphuric acid and/or a mineral acid mixture containing at least 30% by weight sulphuric acid and stirring vigorously, separating the acid solution containing the heavy metal salt or salts from the slurry, and washing and neutralising the slurry so that it is substantially free of acid and metal-ions.
If the concentration of the suspension exceeds the above value, a stable foam may be formed during the acid treatment which considerably slows down the reaction velocity
If the acid or acid mixture employed for the decomposition of the complexes does not contain sulphuric acid, the subsequent separation, sedimentation and filtration of the suspension are considerably more difficult than in the presence of sulphuric acid.
Preferably the suspension is present in a concentration of 20 to 40 kg/cm3 and it is ensured that the acid concentration is not more than 10% by weight of the total weight of the working mixture and the pH of the working mixture is less than 1 after the acid treatment.
The velocity of the decomposition of the complexes is satisfactory at room temperature, therefore the reaction can be successfully carried out at the original, normal temperature of the suspension but by increasing the temperature the reaction is accelerated.
Preferably the acid and slurry are stirred together at a temperature of 20-1 000C for at time depending on the reaction temperature.
After the termination of the temperaturedependent reaction the solid material content of the suspension is concentrated, for example by washing out the heavy metal ions with water or dilute sulphuric acid, neutralizing the residue with slaked lime and separating it from the solution.
The heavy metal salt content of the solution separated from the slurry is concentrated by precipitation and is stored as much in a place appointed for this purpose or alternatively is utilized, if desired, after purification and separation. The process is illustrated by the block diagram shown in on Figure 1.
Example
Chromium ions are removed from a fermented waste slurry of leather manufacturing having the following composition:
dry substance content 200 kg/m3
organic substance content 100 kg/m3
Chromium ion content 12 kg/cm3
The slurry contains traces of zinc and cadmium ions and a substantial amount of iron and calcium ions.
The slurry is admixed with water in a volume ratio of 1:6 in the homogenisator 1 or with the acidic water containing chromium ions, which leaves the washing-separating system. The essentially homogeneous suspension obtained is led into the reactor 2, in which 150 kg of a 96% sulphuric acid are added per 1 m3 of slurry, and the reaction is performed at the actual temperature of the slurry, under vigorous stirring for 60 minutes. The solid material content of the suspension is concentrated in the separator 3, after which the concentrated slurry enters the washing-separating system 4 in which water or dilute sulphuric acid is used to wash out the heavey metal ions, and subsequently the neutralizing-separating system 5. As a final product a slurry free from heavy metal ions is obtained, which is neutralized with slaked lime.
From the washing system 4 the washing liquor is recycled into the homogenisator 1. From the separator 3 the chromium-containing solution is led into the precipitator 6, in which the metal salts are precipitated in the pH-range of 8 to 10 by means of slaked lime. The precipitate containing heavy ions is separated from the alkaline water
in the separator 7.
The process is advantageous in that
it can give a reasonable solution for the problems of environmental protection in connection with waste slurries from the leather and skin industry and makes the establishment of storing lakes and the transportation of toxic slurries superfluous;
it can allow use of slurries having a high organic material content for agricultural purposes, e.g. soil-improvement;
it can give an excellent opportunity for the recovery of the valuable ingredients of the precipitate obtained having a high heavy metal concentration.
Claims (12)
1. A process for the detoxication of waste containing one or more heavy metal salt complexes comprising homogenising a slurry of waste with water to give a suspension of the solid material having a maximum concentration of 100 kg/m3, adding sulphuric acid and/or a mineral acid mixture containing at least 30% by weight sulphuric acid and stirring vigorously, separating the acid solution containing the heavy metal salt or salts from the slurry, and washing and neutralizing the slurry so that it is substantially free of acid and metal-ions.
2. A process according to claim 1, wherein the heavy metal salt or salts is/are precipitated from the extracted solution and separated therefrom.
3. A process according to claim 2, wherein the heavy metal salt or salts is/are precipitated by the addition of slaked lime to the extracted solution at pH 8 to 10.
4. A process according to claim 1, 2 or 3, wherein the suspension is present in a concentration of 20 to 40 kg/m3.
5. A process according to claim 1, 2, 3 or 4, wherein it is ensured that the acid concentration is not more than 10% by weight of the total weight of the working mixture and the pH of the working mixture is less than 1 after the acid treatment.
6. A process according to any one of claims 1 to 5, wherein the acid and slurry are stirred together at a temperature of 20-1 000C for a time depending on the reaction temperature.
7. A process according to any one of claims 1 to 6, wherein the slurry is, after extraction of the heavy metal or salts, neutralised.
8. A process according to claim 7, wherein the slurry is neutralised by the addition of slaked lime.
9. A process according to claim 7 to 8, wherein the slurry is, after extraction of the heavy salt or salts, purified by washing.
10. A process according to any preceding claim, in which the acid washing liquors are recycled to the homogenisator for the preparation of the suspension.
11. A process according to any preceding claim, in which the metal ion-free slurry containing organic materials is used for soilimprovement.
12. A process substantially as herein described with reference to the drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| HU82100A HU185194B (en) | 1982-01-14 | 1982-01-14 | Method for detoxication mixing tannery sewage sludges |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8300987D0 GB8300987D0 (en) | 1983-02-16 |
| GB2113199A true GB2113199A (en) | 1983-08-03 |
| GB2113199B GB2113199B (en) | 1985-07-10 |
Family
ID=10947909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08300987A Expired GB2113199B (en) | 1982-01-14 | 1983-01-14 | Detoxication of industrial waste |
Country Status (10)
| Country | Link |
|---|---|
| CS (1) | CS246057B2 (en) |
| DD (1) | DD209430A5 (en) |
| DE (1) | DE3301120A1 (en) |
| ES (1) | ES8402549A1 (en) |
| GB (1) | GB2113199B (en) |
| HU (1) | HU185194B (en) |
| IT (1) | IT1160174B (en) |
| PL (1) | PL139584B1 (en) |
| RO (1) | RO86780B (en) |
| YU (1) | YU6383A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003042414A1 (en) * | 2001-11-12 | 2003-05-22 | Sicit Chemitech S.P.A. | Chrome-based product in a hydrolyzed proteic compound and process for the making thereof |
| WO2004065028A1 (en) * | 2003-01-21 | 2004-08-05 | Australian Organic Resources Pty Ltd | The extraction and treatment of heavy metals |
| WO2007017402A1 (en) * | 2005-08-05 | 2007-02-15 | Sicit Chemitech S.P.A. | Process for the production of hydrolyzed-protein based products in composition with manganese |
| JP2014036941A (en) * | 2012-08-20 | 2014-02-27 | Swing Corp | Processing method and apparatus of a waste liquid including heavy metals |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3428535A1 (en) * | 1984-08-02 | 1986-02-13 | Siekmann, Helmut E., Prof.Dr.-Ing., 1000 Berlin | METHOD AND DEVICE, IN PARTICULAR FOR THE CONDITIONING OF SEWAGE SLUDGE |
| DE3503199A1 (en) * | 1985-01-31 | 1986-08-07 | Hölter, Heinz, Dipl.-Ing., 4390 Gladbeck | Process for converting sewage sludges into soil improvers and/or fertilisers |
| DE3627253C2 (en) * | 1986-08-12 | 1995-06-22 | Linde Ag | Process for the biological treatment of substrates containing organic substances |
| DE3919788C1 (en) * | 1989-06-16 | 1990-07-05 | Siebtechnik Gmbh, 4330 Muelheim, De | |
| FI97288C (en) * | 1993-08-26 | 1996-11-25 | Kemira Oy | Procedure for treatment of wastewater sludge |
-
1982
- 1982-01-14 HU HU82100A patent/HU185194B/en not_active IP Right Cessation
-
1983
- 1983-01-10 RO RO109659A patent/RO86780B/en unknown
- 1983-01-11 CS CS83182A patent/CS246057B2/en unknown
- 1983-01-11 ES ES518907A patent/ES8402549A1/en not_active Expired
- 1983-01-12 PL PL1983240123A patent/PL139584B1/en unknown
- 1983-01-12 DD DD83247194A patent/DD209430A5/en unknown
- 1983-01-12 YU YU00063/83A patent/YU6383A/en unknown
- 1983-01-13 IT IT19091/83A patent/IT1160174B/en active
- 1983-01-14 GB GB08300987A patent/GB2113199B/en not_active Expired
- 1983-01-14 DE DE19833301120 patent/DE3301120A1/en not_active Withdrawn
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003042414A1 (en) * | 2001-11-12 | 2003-05-22 | Sicit Chemitech S.P.A. | Chrome-based product in a hydrolyzed proteic compound and process for the making thereof |
| WO2004065028A1 (en) * | 2003-01-21 | 2004-08-05 | Australian Organic Resources Pty Ltd | The extraction and treatment of heavy metals |
| EP1638705A1 (en) * | 2003-01-21 | 2006-03-29 | Australian Organic Resources PTY Ltd | The extraction and treatment of heavy metals |
| JP2006515799A (en) * | 2003-01-21 | 2006-06-08 | オーストラリアン・オーガニック・リソーシズ・プロプライエタリー・リミテッド | Heavy metal extraction and treatment |
| AU2004205418B2 (en) * | 2003-01-21 | 2006-11-02 | Australian Organic Resources Pty Ltd | The extraction and treatment of heavy metals |
| US7361283B2 (en) * | 2003-01-21 | 2008-04-22 | Australian Organic Resources Pty. Ltd. | Extraction and treatment of heavy metals |
| EP1638705A4 (en) * | 2003-01-21 | 2011-06-15 | Australian Organic Resources Pty Ltd | The extraction and treatment of heavy metals |
| WO2007017402A1 (en) * | 2005-08-05 | 2007-02-15 | Sicit Chemitech S.P.A. | Process for the production of hydrolyzed-protein based products in composition with manganese |
| JP2014036941A (en) * | 2012-08-20 | 2014-02-27 | Swing Corp | Processing method and apparatus of a waste liquid including heavy metals |
Also Published As
| Publication number | Publication date |
|---|---|
| IT1160174B (en) | 1987-03-04 |
| IT8319091A0 (en) | 1983-01-13 |
| GB8300987D0 (en) | 1983-02-16 |
| RO86780B (en) | 1985-05-31 |
| PL139584B1 (en) | 1987-02-28 |
| DD209430A5 (en) | 1984-05-09 |
| GB2113199B (en) | 1985-07-10 |
| CS246057B2 (en) | 1986-10-16 |
| RO86780A (en) | 1985-05-20 |
| YU6383A (en) | 1985-10-31 |
| PL240123A1 (en) | 1984-06-18 |
| ES518907A0 (en) | 1984-03-01 |
| DE3301120A1 (en) | 1983-07-28 |
| HU185194B (en) | 1984-12-28 |
| ES8402549A1 (en) | 1984-03-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |