Treatment of thallium and heavy metal containing mixed waste water drained by sulfuric acid plant

Abstract

A treatment of mixed waste-water containing T1+ and heavy metal ion(Pb2+, Hg2+, Cd2+ and Cu2+ etc.) from vitriol plant is carried out by adding sulfate fag end 30-60 mesh in proportion of 1:6-1:50 into waste water with pH=1-2, stirring at normal temperature for 30-40mins, adding base into the obtained mixed system, adjusting pH to neutral value(7-8), stirring for 30mins, laying the obtained solution aside for 3-4hrs and discharging supernatant of deposition. It is convenient and cheap.

Description

Technical field: [0001] The invention relates to the technical field of water treatment, in particular to thallium-containing (Tl + ) and heavy metal ions (Pb 2+ , Hg 2+ 、Cd 2+ 、Cu 2+ etc.) mixed wastewater treatment method, which is suitable for the treatment of mixed wastewater containing thallium and heavy metal ions, especially for the treatment of wastewater discharged during the production process of sulfuric acid plants. Background technique: [0002] Wastewater discharged from sulfuric acid plant contains Tl + and Pb 2+ , Hg 2+ 、Cd 2+ 、Cu 2+ and other heavy metal ions, among which the content of thallium can reach 400 μg / L, and the content of other heavy metals is 1-10 mg / L. The method for treating heavy metal wastewater in sulfuric acid plants is usually to deposit lime, because Tl + The hydroxide is soluble in water, and this method cannot handle thallium, so thallium has been discharged directly into the environment all the time. [0003] Wastewater dis...

AI Technical Summary

Problems solved by technology

However, the content of thallium and heavy metals in the wastewater discharged from the sulfuric acid plant is relatively low. Although the pyrite treatment can meet the discharge standards, there are still the following deficiencies: 1. The residual amount of heavy metal ions in the treated wastewater is not ideal; 2. Consume certain resource (pyrite itself is a kind of resource), not economical enough; 3, pyrite needs to be pulverized to more than 150~200 orders, easily causes dust pollution, and the pyrite after the waste water treatment also needs to be disposed of again. more difficult