Method for removing cadmium ion from waste water by waste beer yeast absorption- deposition

Abstract

A method for removing cadmium ions from wastewater by adsorption-precipitation with waste beer yeast comprises the steps of preparing waste beer yeast adsorbent from waste beer yeast, adding into cadmium-containing wastewater solution, adjusting pH in the range of 5-8, stirring at room temperature and stirring speed of 800-1,000 r / min, standing for 120-210 min, and removing the waste beer yeast adsorbent with adsorbed cadmium ions. The inventive method removes cadmium ions from cadmium-containing wastewater by utilizing good cadmium adsorption and good precipitation effect of waste beer yeast; has the advantages of simple process, high treatment efficiency, low cost, and no secondary pollution; and is very important for controlling cadmium-containing wastewater pollution.

Description

Technical field [0001] The invention relates to a method for removing cadmium ions in cadmium-containing wastewater, in particular to a method for treating wastewater with low cadmium ion concentration by using waste beer yeast. Background technique [0002] Cadmium-containing wastewater is one of the most serious and harmful industrial wastewaters. Cadmium and its compounds are widely used in electroplating, pigments, plastic stabilizers, silver-cadmium batteries and alloys. With the increase in the amount of industrial cadmium, the pollution of cadmium is becoming more and more serious. Cadmium is a very toxic heavy metal, which forms cumulative poisoning after entering the human body. China's National Environmental Protection Law stipulates that cadmium is a type of pollutant. [0003] The methods currently used to treat cadmium-containing wastewater include chemical methods and physical chemical methods. The chemical methods are mainly divided into neutralization precipitatio...

AI Technical Summary

Problems solved by technology

[0003] The methods currently used to treat cadmium-containing wastewater include chemical methods and physical chemical methods. Chemical methods are mainly divided into neutralization precipitation method, sulfide precipitation method and ferrite method. Neutralization precipitation method has the advantages of low treatment cost and simple process. , but this method has a large amount of sediment, high effluent hardness, slow reaction speed, and will cause secondary pollution; the sulfide precipitation method is easy to control, and the removal rate of cadmium is high, but the moisture content of the sediment produced by this method is low, resulting in secondary pollution. And the vulcanizing agent is expensive, it is difficult to be widely used in industry; the ferrite method will not cause secondary pollution, but this method is not easy to control, and heavy metals cannot be recovered separately

The physical and chemical methods are mainly divided into ion exchange method and membrane separation method. The disadvantage of ion exchange method is that the resin is easily polluted and the operating cost is high; the membrane separation method is simple in process, but the investment is high, and the membrane pores are easy to block. These shortcomings limit this method. large-scale use of the method

[0004] When the concentration of cadmium ions in the wastewater is low, the above methods all have the disadvantages of relatively high raw material costs and operating costs, which seriously affect economic benefits and cannot meet the needs of protecting the ecological environment.