Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Treatment method of arsenic-containing waste

A treatment method and waste technology, applied in solid waste removal, water/sewage treatment, chemical instruments and methods, etc., can solve the problems of long reaction time, cumbersome scorodite synthesis process, high treatment cost, etc., and achieve improved filtration performance, beneficial to harmless treatment, and the effect of simple treatment process

Active Publication Date: 2016-12-07
SHENZHEN SHENTOU ENVIRONMENT TECH CO LTD
View PDF12 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the above scheme has been improved, the process of synthesizing scorodite is still cumbersome, requiring a high degree of height and a long reaction time. In addition, the mother liquor after precipitation still has a high concentration of arsenic residues, which requires secondary arsenic precipitation, and the treatment cost is high.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] The arsenic-containing electrolytic anode slime containing 5% arsenic is leached by alkaline oxidation with 2mol / L sodium hydroxide, and after recovering valuable metals, a sodium arsenate solution containing 20g / L arsenic is obtained; The slurry of the prepared crystal seed-lepidocite (γ-FeOOH) is added in the reactor, the iron concentration in the slurry is 15g / L, and the total amount of the γ-FeOOH in the crystal seed is 0.1 times of the corresponding arsenic molar weight, Start stirring at room temperature;

[0023] Then slowly add the sodium arsenate solution leached from the arsenic-containing material into the reaction kettle, and at the same time add 20% (mass fraction) ferric chloride solution according to the Fe / As molar ratio of 1:1, and supplement appropriate sodium hydroxide solution (4mol / L) or dilute hydrochloric acid (3mol / L), keep the reaction pH at 4.0;

[0024] After the sodium arsenate solution is added, continue to add a small amount of ferric chl...

Embodiment 2

[0027] The raw material is arsenic trioxide with a content of 95%. Add 4mol / L sodium hydroxide solution according to 1.1 times of the theoretical reaction amount of arsenic trioxide and sodium hydroxide. After all the reaction, add a little excess industrial hydrogen peroxide to convert it all into sodium arsenate solution, the temperature of the solution can reach above 70°C after exothermic reaction.

[0028] First add a small amount of slurry of seed crystals-lepidocite (γ-FeOOH) prepared by the coordination oxidation precipitation method into the reactor, and the amount of seed crystals γ-FeOOH added is 0.1 times the molar amount of arsenic to be treated. The iron concentration of the slurry is 18 g / L, and the stirring is started at 80°C;

[0029] Slowly add sodium arsenate solution to the reaction kettle, and at the same time add 30% (mass fraction) ferric chloride solution according to the Fe / As molar ratio of 1.5, and supplement appropriate sodium hydroxide solution (4m...

Embodiment 3

[0033] The raw material is non-ferrous smelting waste residue containing 5% arsenic. Add 8 mol / L sodium hydroxide to dissolve according to 1.05 times of the theoretical reaction volume. After all the reaction, add a little excess industrial hydrogen peroxide to make it completely converted into sodium arsenate solution. After the exothermic reaction, the temperature of the solution can reach above 70°C.

[0034] First, a small amount of slurry of seed crystals-lepidocite (γ-FeOOH) prepared by the coordination oxidation precipitation method was added to the reactor, and the amount of γ-FeOOH added to the seeds was 0.1 times the molar amount of arsenic corresponding to the treatment. The iron concentration of the material is 20 g / L, and the stirring is started at 60°C;

[0035] Slowly add sodium arsenate solution into the reaction kettle, and at the same time add saturated ferric sulfate solution according to Fe / As molar ratio of 1.5, and supplement appropriate sodium hydroxide ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a recycling treatment method of hazardous arsenic-containing waste. The recycling treatment method comprises the steps of carrying out alkaline leaching on a high-arsenic material to obtain a high-concentration sodium arsenite solution or a high-concentration sodium arsenate solution, and completely converting the high-concentration sodium arsenite solution or the high-concentration sodium arsenate solution into sodium arsenate through oxidation; adding a small amount of seed crystal-lepidocrocite (gamma-FeOOH) slurry into a reaction kettle; slowly adding an arsenic-containing solution; adding a slightly excessive high-concentration malysite solution; maintaining the reaction pH to be 3.5 to 5.5 through adding a neutralizer; and controlling the temperature in the reaction process to enable arsenic in the solution to completely react and totally deposit, wherein an obtained deposit is easy to filter, harmless and stable treatment of the arsenic-containing solution can be achieved, when the method is utilized to deposit arsenic, the concentration of arsenic in filtrate after reaction can directly reach the standard, and secondary arsenic deposition is avoided. The treatment method is simple in technological process, low in cost and applicable to industrial application.

Description

technical field [0001] The invention discloses a treatment and disposal method for arsenic-containing hazardous waste, which belongs to the field of hazardous waste treatment and is suitable for the treatment of arsenic-containing industrial wastewater and waste. Background technique [0002] Arsenic is one of the main associated elements in non-ferrous metal ores, such as high-arsenic copper and gold concentrates, the content of arsenic can even be as high as 20-30%. Various arsenic-containing solutions, arsenic-containing fumes and waste residues are often produced in the non-ferrous metal smelting process, and these arsenic-containing materials are highly toxic, and arsenic must be treated harmlessly. [0003] The comparatively systematic treatment methods of arsenic-containing wastewater include chemical precipitation method, physical method and microbial method. Widely used chemical methods mainly include neutralization precipitation method, flocculation precipitation ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B09B3/00C02F1/00C02F1/62A62D3/00
CPCA62D3/00A62D3/38A62D2101/43B09B3/00C02F1/00C02F2101/20
Inventor 毛谙章周兆安米永红张银亮李钧刘小文彭娟郑帅飞赵陈冬
Owner SHENZHEN SHENTOU ENVIRONMENT TECH CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com