Treatment method for high-ammonia-nitrogen wastewater

Abstract

The invention relates to a treatment method for high-ammonia-nitrogen wastewater. The treatment method comprises the following steps: performing water quality regulation treatment on raw water, performing coagulating sedimentation treatment on the regulated raw water; intercepting macromolecular particulate matters, colloids and suspended matters in liquid supernatant subjected to coagulating sedimentation treatment on a sand filter; feeding wastewater with high ammonia nitrogen discharged from the sand filter to a heat pump stripping system; heating and pressurizing low-temperature carbon ammonia steam which enters the tower top in a rectifying tower through heat exchange in a steam compressor, performing stripping ammonia removal with wastewater in the rectifying tower; feeding a carbon ammonia stock solution into a high-pressure reverse osmosis membrane element to perform concentration-extracting treatment; and feeding a reverse osmosis membrane concentrated solution into a carbonization tower to react with carbon dioxide gas to continuously crystallize, and performing centrifugal separation to obtain ammonium carbonate crystal for being recycled. The treatment method has the characteristics of being good in ammonia removal effect, relatively low in investment and operation cost and low in energy consumption.

Description

technical field [0001] The invention relates to a treatment method for high-ammonia-nitrogen wastewater, and belongs to the technical field of high-ammonia-nitrogen wastewater treatment. Background technique [0002] In recent years, with the improvement of people's living standards, the strengthening of environmental requirements, the strengthening of environmental pollution control and the development of environmental protection technology, the organic pollution of water bodies has basically been effectively controlled, but the discharge of waste water containing high ammonia nitrogen has not been effectively controlled. . High ammonia nitrogen wastewater mainly comes from industries such as coking, chemical fertilizer, petrochemical, breeding, and garbage disposal. In terms of high ammonia nitrogen wastewater treatment, it is not only necessary to pursue high-efficiency denitrification technical indicators, but also to consider reducing energy consumption, saving energy,...

AI Technical Summary

Problems solved by technology

The deamination process uses lime or sodium hydroxide to increase the alkalinity of ammonia nitrogen wastewater, and uses the principle of separation of free ammonia and water for deamination, which has high dosing costs and low separation efficiency

In addition, the cooling water is used to condense the ammonia vapor and return it, and the concentration of ammonia in the reflux liquid is continuously increased before extraction, which not only consumes high energy consumption, but also consumes a large amount of cooling water resources

Since ammonia water cannot be concentrated by the membrane, it can only be concentrated through heat-driven rectification, deammonization and enrichment, and the process investment and operating costs are high

However, the traditional process uses freezing and crystallization to obtain ammonium carbonate products, which has high investment and operating costs, and the system is unstable and the product is easy to decompose. Therefore, there are low efficiency of the deamination process, high energy consumption, and difficult resource utilization of the product.

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