CN104478123A

CN104478123A - Method for treating mercury-containing mineral processing tail water

Info

Publication number: CN104478123A
Application number: CN201410688778.6A
Authority: CN
Inventors: 周吉奎; 喻连香
Original assignee: GUANGDONG RESEARCH INSTITUTE OF INDUSTRIAL TECHNOLOGY (GUANGZHOU RESEARCH INSTITUTE OF NON-FERROUS METALS)
Current assignee: GUANGDONG RESEARCH INSTITUTE OF INDUSTRIAL TECHNOLOGY (GUANGZHOU RESEARCH INSTITUTE OF NON-FERROUS METALS)
Priority date: 2014-11-26
Filing date: 2014-11-26
Publication date: 2015-04-01

Abstract

The invention relates to a method for treating mercury-containing mineral processing tail water. The content of sodium silicate in the mineral processing tail water is 1,000-3,000mg/L, the content of solids in the mineral processing tail water is 1,150-2,650mg/L, and the content of mercury in the mineral processing tail water is 1.5-2.5mg/L. The method is characterized by comprises the following steps: adding calcium oxide or calcium hydroxide into the mercury-containing mineral processing tail water, stirring, and enabling the pH value to be 9-10; adding a polymeric ferric sulfate aqueous solution into the tail water in a manner that 1-2mL of polymeric ferric sulfate aqueous solution, of which the iron content is 1mol/L, is added into per liter of tail water, and stirring; then, adding calcium oxide or calcium hydroxide, stirring, and enabling the pH value to be 9-10; adding a polyacrylamide aqueous solution into the tail water in a manner that 1-2mL of 0.1wt% polyacrylamide aqueous solution is added into per liter of tail water, uniformly stirring, then, carrying out natural sedimentation for 5-10 minutes, extracting a supernatant, then, filtrating, merging the filtrate and the supernatant, adjusting the pH value to 6.5-7.5 with a sulfuric acid solution, and then, carrying out standard-reaching discharging or recycling for mineral processing. The method disclosed by the invention can be used for effectively removing mercury from the sodium-silicate-containing mineral processing tail water, the content of mercury in the treated water is lower than 0.05mg/L, and the content of the solids in the treated water is lower than 50mg/L.

Description

A kind of method processing mercurous ore dressing tail water

Technical field

The present invention relates to a kind of method processing mercurous ore dressing tail water.

Background technology

Mercury-containing waste water endangers one of maximum trade effluent in the world.Enter the mercury and mercuric compounds in water body, the mercury of various form is formed through physical chemistry and biological action, especially the methyl compounds that toxicity is very large is changed into, accumulate greatly through hydrobiont and fish richness, this mercurous water of mankind's life-time service and edible mercury contaminated fish, shellfish, mercury and mercuric compounds will enter in body through digestive tube, and the coloured glaze base on human chitinase albumen is combined, the metabolism of block cell, thus cause mercury poisoning.Separately have report to show, mercury also can have an impact to self-purification of waters and waste water disposal facility etc., and the valve concentration that mercury affects water quality situation is 0.01mg/L, and mercury concentration 2.5 ~ 5.0mg/L has lethal effect to the microorganism system in waste water disposal facility.

The method of current process mercury-containing waste water has chemical precipitation method, metal deoxidization, active carbon adsorption, ion exchange method, microbial method etc., not containing water glass in mercury-containing waste water handled by these methods, and the present invention be directed to the treatment process of the mercury-containing waste water containing water glass.

Use water glass to make inhibitor in mercurous ore beneficiation flow process, cause in tail water containing a large amount of water glass.Silicate anion is electronegative, and there is hydration layer on surface, silicic acid micelle stably can be dispersed in water body, and can not reunite mutually and sedimentation.When this micelle and silicate anion are adsorbed on sludge surface, just make sludge be in dispersion state, be difficult to sedimentation.This ore dressing tail water mesosilicic acid sodium content 1000 ~ 3000mg/L, solid contents is up to 1150 ~ 2650mg/L, and mercury content is up to 1.5 ~ 2.5mg/L, and most of mercury is present in microfine solids.In waste water, solid contents and mercury content have all exceeded industrial wastewater discharge standard, cause such vacuum in draft tube and discharge very difficult.

Summary of the invention

The object of the invention is the defect overcoming prior art, a kind of method processing mercurous ore dressing tail water is provided, realizes vacuum in draft tube or qualified discharge.

Concrete steps of the present invention are as follows: calcium oxide or calcium hydroxide are added mercurous ore dressing tail water, stir, make pH value be 9 ~ 10; Add by often liter of tail water the polyaluminum sulfate water solution that 1 ~ 2mL iron level is 1mol/L, stir; Add calcium oxide or calcium hydroxide again, stir, make pH value be 9 ~ 10; The polyacrylamide solution that 1 ~ 2mL massfraction is 1 ‰ is added by often liter of tail water, natural subsidence 5 ~ 10min after stirring, filter after extracting supernatant liquor out, filtrate and supernatant liquor merge, and adopt the rear qualified discharge in sulphuric acid soln adjust pH to 6.5 ~ 7.5 or are back to ore dressing.

In the present invention, calcium oxide or calcium hydroxide are coagulants, and calcium ion and silicic acid, with reaction, produce precipitated calcium silicate, destroy the colloidal stability of ore dressing tail water mesosilicic acid sodium, contribute to the sedimentation of micro-solid particle in tail water; Then bodied ferric sulfate is adopted to make coagulating agent, calcium oxide or calcium hydroxide, sulfuric acid do pH adjusting agent, polyacrylamide does coagulant aids, catch sieve sweep volume effect by absorption neutralization, adsorption bridging, flco, accelerate the flocculation settling velocity of the various ion such as micro-solid particle and arsenic, mercury, copper, lead, calcium in water body, thorough purifying water body.

Compared with the prior art, the present invention is advantageously: method of the present invention can effectively be removed containing the mercury in the ore dressing tail water of water glass, after process, the content of Mercury in Water Body is less than 0.05mg/L, and solid contents is less than 50mg/L, can qualified discharge or be back to ore dressing.

Embodiment

By following instance, the invention will be further described.

Embodiment 1

Ore dressing tail water mesosilicic acid sodium content 2g/L, mercurous 1.5mg/L, solid contents 1760mg/L, adopt following steps to process:

Under rotating speed 150rpm stirs, repeatedly add calcium oxide, the change of on-line monitoring pH value in a small amount, when pH value is stabilized in 9.5, stop to add calcium oxide; Add the 1mol/L polyaluminum sulfate water solution of 1mL by often liter of tail water, continue to stir, more repeatedly add calcium oxide, the change of on-line monitoring pH value in a small amount, when pH value is stabilized in 9, stop to add calcium oxide; By 1 ‰ polyacrylamide solutions adding 1mL in often liter of tail water, after stirring, natural subsidence 8min, filters after extracting supernatant liquor out, and filtrate and supernatant liquor merge, with the discharge of sulphuric acid soln adjust pH to 7.0 or for ore dressing.After testing, the tail water water glass content 0.22g/L after process, mercury content 0.03mg/L, solid contents 41.6mg/L.

Embodiment 2

Ore dressing tail water mesosilicic acid sodium content 2.5g/L, mercurous 2.3mg/L, solid contents 2150mg/L, adopt following steps to process:

Under rotating speed 200rpm stirs, repeatedly add calcium oxide, the change of on-line monitoring pH value in a small amount, when pH value is stabilized in 9.5, stop to add calcium oxide; Add the 1mol/L polyaluminum sulfate water solution of 1.5mL by often liter of tail water, continue to stir, more repeatedly add calcium oxide, the change of on-line monitoring pH value in a small amount, when pH value is stabilized in 9.5, stop to add calcium oxide; By 1 ‰ polyacrylamide solutions adding 1.5mL in often liter of tail water, after stirring, natural subsidence 10min, filters after extracting supernatant liquor out, and filtrate and supernatant liquor merge, with the discharge of sulphuric acid soln adjust pH to 7.0 or for ore dressing.After testing, the tail water water glass content 0.23g/L after process, mercury content 0.03mg/L, solid contents 47.5mg/L.

Claims

1. the method for the mercurous ore dressing tail water of process, described ore dressing tail water mesosilicic acid sodium content 1000 ~ 3000mg/L, solid contents 1150 ~ 2650mg/L, mercury content 1.5 ~ 2.5mg/L, it is characterized in that being made up of following steps: calcium oxide or calcium hydroxide are added mercurous ore dressing tail water, stir, make pH value be 9 ~ 10; Add by often liter of tail water the polyaluminum sulfate water solution that 1 ~ 2mL iron level is 1mol/L, stir; Add calcium oxide or calcium hydroxide again, stir, make pH value be 9 ~ 10; The polyacrylamide solution that 1 ~ 2mL massfraction is 1 ‰ is added by often liter of tail water, natural subsidence 5 ~ 10min after stirring, filter after extracting supernatant liquor out, filtrate and supernatant liquor merge, and adopt the rear qualified discharge in sulphuric acid soln adjust pH to 6.5 ~ 7.5 or are back to ore dressing.