CN101502840B - Harmless treatment technique of solid dangerous waste - Google Patents
Harmless treatment technique of solid dangerous waste Download PDFInfo
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- CN101502840B CN101502840B CN2009100966092A CN200910096609A CN101502840B CN 101502840 B CN101502840 B CN 101502840B CN 2009100966092 A CN2009100966092 A CN 2009100966092A CN 200910096609 A CN200910096609 A CN 200910096609A CN 101502840 B CN101502840 B CN 101502840B
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- waste
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- harmless treatment
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- 239000002699 waste material Substances 0.000 title claims abstract description 47
- 238000000034 method Methods 0.000 title claims abstract description 39
- 239000007787 solid Substances 0.000 title claims abstract description 19
- 231100000331 toxic Toxicity 0.000 claims abstract description 17
- 230000002588 toxic effect Effects 0.000 claims abstract description 17
- 229910052785 arsenic Inorganic materials 0.000 claims abstract description 16
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000003814 drug Substances 0.000 claims abstract description 11
- 230000006641 stabilisation Effects 0.000 claims abstract description 11
- 239000004568 cement Substances 0.000 claims abstract description 9
- 238000011105 stabilization Methods 0.000 claims abstract description 7
- 159000000007 calcium salts Chemical class 0.000 claims abstract description 3
- 159000000003 magnesium salts Chemical class 0.000 claims abstract description 3
- LQNUZADURLCDLV-UHFFFAOYSA-N nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1 LQNUZADURLCDLV-UHFFFAOYSA-N 0.000 claims description 26
- 238000007254 oxidation reaction Methods 0.000 claims description 16
- 230000003647 oxidation Effects 0.000 claims description 15
- 150000002894 organic compounds Chemical class 0.000 claims description 13
- 238000006243 chemical reaction Methods 0.000 claims description 12
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims description 8
- 150000003839 salts Chemical class 0.000 claims description 7
- 239000002912 waste gas Substances 0.000 claims description 7
- 239000003513 alkali Substances 0.000 claims description 5
- 239000012028 Fenton's reagent Substances 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 3
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 3
- 230000007062 hydrolysis Effects 0.000 claims description 3
- 238000006460 hydrolysis reaction Methods 0.000 claims description 3
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 3
- 239000004571 lime Substances 0.000 claims description 3
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims description 2
- 159000000013 aluminium salts Chemical class 0.000 claims description 2
- 229910000329 aluminium sulfate Inorganic materials 0.000 claims description 2
- 238000006386 neutralization reaction Methods 0.000 claims description 2
- 239000002920 hazardous waste Substances 0.000 abstract description 9
- 238000005516 engineering process Methods 0.000 abstract description 8
- 231100000419 toxicity Toxicity 0.000 abstract description 7
- 230000001988 toxicity Effects 0.000 abstract description 7
- 238000007711 solidification Methods 0.000 abstract description 4
- 230000008023 solidification Effects 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 229940079593 drug Drugs 0.000 abstract 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 abstract 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 abstract 1
- 238000011109 contamination Methods 0.000 abstract 1
- 239000011780 sodium chloride Substances 0.000 abstract 1
- 239000007790 solid phase Substances 0.000 abstract 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M sodium hydroxide Inorganic materials [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 231100000816 toxic dose Toxicity 0.000 description 8
- 239000002351 wastewater Substances 0.000 description 6
- 238000001723 curing Methods 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 3
- 238000002386 leaching Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 239000002893 slag Substances 0.000 description 3
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 description 2
- DJHGAFSJWGLOIV-UHFFFAOYSA-N Arsenic acid Chemical compound O[As](O)(O)=O DJHGAFSJWGLOIV-UHFFFAOYSA-N 0.000 description 2
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 2
- FZERHIULMFGESH-UHFFFAOYSA-N N-phenylacetamide Chemical compound CC(=O)NC1=CC=CC=C1 FZERHIULMFGESH-UHFFFAOYSA-N 0.000 description 2
- 239000003674 animal food additive Substances 0.000 description 2
- 229940000488 arsenic acid Drugs 0.000 description 2
- 238000010790 dilution Methods 0.000 description 2
- 239000012895 dilution Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- FBAFATDZDUQKNH-UHFFFAOYSA-M iron chloride Chemical compound [Cl-].[Fe] FBAFATDZDUQKNH-UHFFFAOYSA-M 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 238000009303 advanced oxidation process reaction Methods 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000011790 ferrous sulphate Substances 0.000 description 1
- 235000003891 ferrous sulphate Nutrition 0.000 description 1
- 238000002290 gas chromatography-mass spectrometry Methods 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 238000001095 inductively coupled plasma mass spectrometry Methods 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910001629 magnesium chloride Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 239000002957 persistent organic pollutant Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000004537 pulping Methods 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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Abstract
The invention discloses a solid hazardous waste decontaminating treatment technology, toxic organic matters in wastes are oxidized and degraded by a solid phase system Fenton, in the meantime, toxic inorganic matters like As(III) in the wastes can be converted into As(V) to further reduce toxicity of arsenic; then cement is added for solidification, at least one of saline medicines such as ferricsalts, magnesium salts, aluminum salts, calcium salt and the like can be added for stabilization before the solidification, and the toxic inorganic matters in the wastes are fixed. The invention has excellent technological treatment effect, simple technology, easy operation and economical and easily-available used medicines, in addition, by means of reasonable arrangement, the generation of secondary contamination can be avoided in the process of the treatment.
Description
Technical field
The present invention relates to a kind of harmless treatment technique of solid dangerous waste, particularly a kind of harmless treatment process that contains the hazardous waste of arsenic and/or nitrobenzene-containing toxic organic compound.
Background technology
Produce the waste residue that feed addictive phenalgin arsenic acid and Luo Keshasheng are produced, and the sediment of waste water processing station materialization processing section contains arsenic and toxic organic compound (being mainly nitrobenzene matters and aniline category matter) usually simultaneously in the factory, according to " hazardous waste register " (2008), this waste residue belongs to hazardous waste, is numbered HW02 (pharmaceutical wastes-275-001-02).Waste residue is adopted methods such as GC-MS and ICP-MS detect, and contrast " the hazardous waste judging standard leaches toxicity and differentiates " (GB5085.3-2007), show that nitrobenzene and arsenic are main control pollutant.Not only contain organic pollution but also contain inorganic pollution in this refuse, intractability is bigger.Treatment technology to such hazardous waste still lacks at present, and organic arsenic feed additive industry (phenalgin arsenic acid and Luo Keshasheng) has been listed in by relevant departments and polluted the industry blacklist, orders the regulation that stops production.
The Fenton oxidation processing technique is widely used in wastewater treatment at present and contaminated soil is handled, and discloses a kind of Fenton two-stage method oxidation processing technique for paper-making pulping waste water such as Chinese invention patent application 200710114887.7, oxidant H
2O
2Under catalyst Fe (II), generate the OH of strong oxidizing property, can remove hardly degraded organic substance.But be not useful on the report that solid dangerous waste is handled at present as yet.In addition, because the Fenton oxidation technology usually in aqueous phase system when contaminated soil (handle in mud reactor) carry out, its solid-to-liquid ratio generally is higher than 5: 1, can produce waste water in the processing procedure, and the processing of this waste water produces mud once more, thereby the secondary pollution problem is progressively amplified.
Summary of the invention
The invention provides a kind of method of handling solid dangerous waste, the degraded of nitrobenzene matters or other toxic organic compounds in the realization hazardous waste, simultaneously the As (III) of waste residue can be converted into As (V), further reduce the toxicity of arsenic, then the arsenic in the waste residue is fixed, and can not be caused secondary pollution.
A kind of harmless treatment technique of solid dangerous waste may further comprise the steps:
(1) will add after the waste residue weighing in the Fenton oxidation reactor, according to an amount of Fenton reagent (H of content adding of toxic organic compound in the waste residue
2O
2And ferrous salt) reacts about 20-60min of reaction time;
The dosage of Fenton reagent can be decided according to the amount of toxic organic compound in the waste residue, general H
2O
2Dosage be H
2O
2: waste residue=0.5-1.5: 1; When the content of toxic organic compound in the waste residue when 10000ppm is following, adopting mass percentage concentration is the H of 1%-10%
2O
2, the dosage of ferrous salt medicament is ferrous salt: waste residue=0.04-1: 1; When the concentration of toxic organic compound in the waste residue more than 10000ppm, to adopt mass percentage concentration be the H of 10%-30%
2O
2, the dosage of ferrous salt medicament is salt molysite: waste residue=0.5-5: 1;
In this course of reaction, the oxidized degraded of toxic organic compound if contain toxic bigger As (III), also is converted into the less relatively As of toxicity (V) in the waste residue, and the toxic organic compound waste gas that produces in the course of reaction adopts dilute acid soln to absorb;
After reaction finishes, waste residue is carried out toxicity characteristic leaching procedure, if the leaching toxic concentration of toxic organic compound does not wherein reach " the hazardous waste judging standard leaches toxicity and differentiates " standard (GB5085.3-2007), then carry out solid system Fenton oxidation processes again;
(2) material through solid system Fenton oxidation processes adds cement solidification, and the cement ratio of adding is a cement: waste residue (mass ratio)=1.5~4: 1;
When the content of arsenic in the waste residue is higher, can add at least a stabilization processes of carrying out in the salt medicaments such as molysite, magnesium salts, aluminium salt, calcium salt, dosage is decided by the content of arsenic, be generally the salt medicament: arsenic (mol ratio)=1.5~4: 1, then add cement again and be cured processing, Fe
3+, Mg
2+Plasma settles out the soluble state arsenic in the waste residue with effects such as absorption, precipitations, makes it to be difficult for being dissolved out from waste residue contaminated environment;
Anion concentration is (such as SO in waste residue
4 2-) when higher, be unfavorable for cement solidification, can add an amount of white lime, Ca
2+With SO
4 2-Reaction generates gypsum, thereby reduces SO
4 2-Influence;
The sour gas that is produced by the hydrolysis of salt medicament in the stabilization procedures absorbs by alkali lye to be removed;
Cured block after the curing need carry out maintenance, cured block after the maintenance is leached toxic concentration to be detected, if the leaching toxic concentration of arsenic is greater than 5mg/L, surpass " the hazardous waste judging standard leaches toxicity and differentiates " (GB5085.3-2007), cured block is broken into pieces carried out stabilisation/curing processing again.
The dilute acid soln that absorbs waste gas mixes the neutralization back and handles water as solidifying after the Fenton oxidation processes with alkali lye, make this technology not produce waste water.
The present invention adopts better simply Fenton oxidation technology and stabilisation/curing process to be processed into relatively complicated not only the including organic pollutants but also comprise the solid dangerous waste of inorganic pollution of branch, treatment effect is good, and technology is simple to operation, and the medicament that is adopted also economy is easy to get.
Description of drawings
Fig. 1 is a kind of process flow diagram of the inventive method.
The specific embodiment
As shown in Figure 1, organic arsenic feed additive is produced waste residue leach the toxic concentration evaluation, if nitrobenzene and arsenic are all below standard, then carry out solid system Fenton oxidation processes earlier and remove nitrobenzene matters, the Fenton ratio of reagents that adds is: H
2O
2(mass percentage concentration 18%-30%) 0.5m
3/ t waste residue, ferrous sulfate pulvis 0.04t/t waste residue.The nitrobenzene waste gas that produces in the course of reaction then adopts dilution heat of sulfuric acid to absorb by spray column, reaction time 20-30min, and the nitrobenzene that reaction finishes to detect the back leaches toxic concentration, can carry out next step stabilisation/curings processing after up to standard.
To be transferred in the concrete mixer through the material of solid system Fenton oxidation processes, open mixer, slowly add iron chloride, the ratio of adding is the 0.2t/t waste residue, and 15-20min adds and finishes, stirring reaction 15min, slowly add magnesium chloride (0.25t/t slag) and white lime (0.2t/t slag), stirring reaction 15min adds cement (1.6t/t slag), stirring reaction 30min, finally add an amount of water again, stirring reaction 15min then carries out the discharging molding, after the demoulding maintenance 7-11 days.The HCl gas that is produced by the iron chloride hydrolysis in the stabilization procedures is absorbed by NaOH solution by gas skirt and spray column to be removed.
The dilution heat of sulfuric acid that has absorbed nitrobenzene matters waste gas in the solid system Fenton oxidation processes is removed wherein nitrobenzene organic matter by the Fenton oxidation processes, Fenton reaction optimal pH is about 3, mix with the alkali lye of absorption waste gas in the stabilization process afterwards, make the pH value be tending towards neutral.Absorption liquid after the processing can be used for solidifying handles (cured block needs water to be cured), so this harmless treatment process will not produce waste water.
Handle through above-mentioned Fenton advanced oxidation processes and stabilisation/curing process, nitrobenzene matters leaches toxic concentration and reduces to 19.8mg/L from 600-800mg/L, and wherein nitrobenzene leaches toxic concentration and reduces to 0.5-1.0mg/L from 50mg/L; Arsenic leaches toxic concentration and reduces to 0.98-3.1mg/L from 700-1000mg/L.
Claims (4)
1. harmless treatment technique of solid dangerous waste that contains arsenic and/or nitrobenzene-containing toxic organic compound may further comprise the steps:
(1) solid system Fenton oxidation processes:
Waste residue and Fenton reagent are carried out oxidation reaction, and described Fenton reagent is H
2O
2And ferrous salt; The waste gas that produces in the course of reaction absorbs with dilute acid soln to be removed;
(2) solidify processing
Be cured processing through adding cement in the waste residue of solid system Fenton oxidation processes;
Add the salt medicament before solidify handling and carry out stabilization processes, described salt medicament is at least a in molysite, magnesium salts, aluminium salt, the calcium salt;
The sour gas that is produced by the hydrolysis of salt medicament in the stabilization processes process absorbs by alkali lye to be removed;
The dilute acid soln that absorbs waste gas after the Fenton oxidation processes, mixes neutralization with alkali lye after, as solidifying the processing water.
2. harmless treatment technique of solid dangerous waste as claimed in claim 1 is characterized in that: solidify and handle the preceding white lime that adds.
3. harmless treatment technique of solid dangerous waste as claimed in claim 1 is characterized in that: when the content of toxic organic compound in the waste residue when 10000ppm is following, adopting mass percentage concentration is the H of 1%-10%
2O
2, H
2O
2With the mass ratio of waste residue be 0.5-1.5: 1, the mass ratio of ferrous salt and waste residue is 0.04-1: 1; When the concentration of toxic organic compound in the waste residue when 10000ppm is above, adopting mass percentage concentration is the H of 10%-30%
2O
2, H
2O
2With the mass ratio of waste residue be 0.5-1.5: 1, the mass ratio of ferrous salt and waste residue is 0.5-5: 1.
4. harmless treatment technique of solid dangerous waste as claimed in claim 1 is characterized in that: the cement that the curing processing adds and the mass ratio of waste residue are 1.5~4: 1.
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CN2009100966092A CN101502840B (en) | 2009-03-10 | 2009-03-10 | Harmless treatment technique of solid dangerous waste |
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CN2009100966092A CN101502840B (en) | 2009-03-10 | 2009-03-10 | Harmless treatment technique of solid dangerous waste |
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CN101502840A CN101502840A (en) | 2009-08-12 |
CN101502840B true CN101502840B (en) | 2010-08-04 |
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Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102247967B (en) * | 2010-05-18 | 2014-10-08 | 上海复拓环境技术有限公司 | Harmless treatment process for arsenic-containing waste dangerous chemicals |
CN102247685B (en) * | 2010-05-18 | 2015-02-25 | 上海复拓环境技术有限公司 | Harmless treatment process for mercury-containing waste dangerous chemicals |
CN102218428A (en) * | 2011-01-20 | 2011-10-19 | 杭州大地环保有限公司 | Treatment method of arsenic slag |
CN104043645B (en) * | 2014-06-13 | 2016-02-10 | 中国科学院武汉岩土力学研究所 | A kind of arsenic Polluted Soil restorative procedure |
CN104525555B (en) * | 2014-12-29 | 2016-09-07 | 中国电建集团中南勘测设计研究院有限公司 | A kind of stabilization treatment method for arsenic slag and equipment |
CN106362347A (en) * | 2016-08-04 | 2017-02-01 | 北京南科大蓝色科技有限公司 | Treating method for high-concentration arsenic slag |
CN113426805B (en) * | 2021-06-22 | 2022-10-14 | 扬州杰嘉工业固废处置有限公司 | Harmless treatment method for alkaline arsenate waste residues |
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