Method for removing chloride ion in sewage

Abstract

The invention discloses a method for processing wastewater containing chloride ions. The method comprises the following steps of carrying out flocculation precipitation treatment on chlorine wastewater by polymeric ferrous sulfate, adding 1-5ppt of mercury nitrate reagent to the chlorine wastewater in which suspended particles are removed, adjusting pH value to 9.5-11.5, fully stirring for 10-30 minutes to completely react, then adding excessive sodium sulfate and sodium oxalate to 500-1000mg / L of wastewater, continuing to leach for 30-50 minutes at normal pressure, and precipitating the residual trace mercury ion in the wastewater; finally enabling the wastewater to flow through an absorption tower with a biomass filter material to carry out adsorption treatment, wherein the effluent is the wastewater in which the chloride ions are completely removed, and the biomass filter material is particles of 80-100 meshes which are prepared from straw and sawdust in the manners of baking, crushing and pelletizing after anaerobic fermentation. The method has the characteristics that the method is simple in technologic process, low in operating expense, free of sludge, high in chloride ion removal rate, and the like.

Description

technical field [0001] The invention relates to a method for removing chloride ions in sewage, relates to the removal of chloride ions in waste water, and belongs to the field of waste water treatment in environmental protection. Background technique [0002] In the process of industrial reverse osmosis treatment, oil extraction process, and printing and dyeing process, some chlorine-containing wastewater with a chloride ion content of 500mg / L-1000mg / L is often produced. Excessive chlorine ion content in wastewater will damage the quality of water and inhibit the growth of microorganisms. Chlorine will chemically react with organic matter in water to generate a series of chlorinated hydrocarbons, which will cause cancer to a certain extent on the human body. Therefore, the treatment of chlorine-containing wastewater It is of great significance in environmental governance. [0003] At present, there are several methods for removing chloride ions in wastewater: (1) precipitat...

AI Technical Summary

Problems solved by technology

[0003] At present, there are several methods for removing chloride ions in wastewater: (1) precipitation method, using silver nitrate to precipitate chloride ions, which is too expensive in industry and not widely used, and is limited to laboratory use; (2) ion exchange Chloride ions are removed by double bed or mixed bed, which is a traditional process with low equipment investment and low operating cost, but the anion exchange resin is easily saturated and needs to be regenerated; (3) Electrodialysis is suitable for treating low-concentration chlorine-containing wastewater , water consumption and power consumption are large; (4) Reverse osmosis (RO membrane method) has a higher removal rate than electrodialysis, and is easy to operate, but the investment is large, and the membrane is easy to clog, so it is not suitable for treating high conductivity and high ion concentration. waste water

[0004] Publication No. is CN101121549, and the name is called "method for treating waste water containing ammonium and chlorine and recycling ammonium and chlorine". Concentrated sulfuric acid is added to the wastewater, followed by heating and distillation to remove chloride ions, but the use of concentrated sulfuric acid is very dangerous and not suitable for the removal of high-concentration chloride ions; the publication number is CN101723486A, and the name is "a salt-containing, chlorine-containing Wastewater Treatment Method” patent describes the use of electrochemical catalytic oxidation method to treat chlorine-containing wastewater. This method is complex in operation, low in treatment effect, and high in cost, making it difficult to apply industrially.