Method for simultaneous removal of heavy metals and organic matters from wastewater

#The present invention relates generally to the field of industrial wastewater treatment and more specifically, to a treatment method for simultaneously removing heavy metals and organic matters from wastewater.

#Heavy metals and organic pollutants coexist in industrial wastewater from electroplating, metal smelting, tannery, textile production, printing, dyeing, paper making, and other industries.

#For wastewater containing heavy metals and organic matters, traditional treatment is a step-by-step method, which removes heavy metals and organic matters separately. Heavy metals are removed by chemical static precipitation or physical adsorption. And for organic matter removal, wastewater with suitable B/C is treated using traditional activated sludge or biofilm method, while advanced oxidation process is used for industrial wastewater which is difficult to be biochemically treated. In addition, the methods for simultaneous removal of heavy metals and organic matters include adsorption, membrane separation, photocatalysis, and ferric oxide coagulation. Activated carbon, bentonite, diatomite, chitosan, and other adsorbents are used to remove various pollutants in the adsorption process, and the adsorption capacity of heavy metals and organic compounds can be improved further by modification. Membrane separation removes pollutants by pressure difference and potential difference, with neutralization and micelle strengthening can be adopted when the membrane pore size is too large to intercept organic pollutants. However, adsorption and membrane separation methods have the problems of limited adsorption removal capacity, periodic cleaning and replacement of membranes. The photocatalytic system of titanium dioxide is capable of simultaneously removing organics as electron donors and heavy metals as electron acceptors via electron-hole pairs, but with the defects of high cost and poor stability, which makes it difficult to be applied for large-scale engineering applications.

#FIG. 1 represents the process flow chart of this invention.

#In this figure, 1-primary sedimentation tank, 2-adjusting tank, 3-anoxic reactor, 4-aerobic reactor, 5-secondary sedimentation tank, 6-incubation pool.

#Specific Implementing Operation

#The present invention is described in detail below combined with specific examples. The following practical examples will help those skilled in the art to further understand this invention, but will not restrict this invention in any form. It should be pointed out that for common technicians in the art, a certain amount of variations and modifications can be made under prerequisite of not departing from the concept of this invention, which belongs to the scope of protection of this invention.