Wastewater zero discharge system based on efficient concentrating and spray drying integrated treatment

Abstract

The invention provides a wastewater zero discharge system based on efficient concentrating and spray drying integrated treatment, which is characterized in that desulfurization wastewater is collected into a wastewater collection tank, the wastewater collection tank and a wastewater lifting pump are in liquid level linkage, the wastewater lifting pump conveys desulfurization wastewater stock solution to a preheater, the preheater preheats the desulfurization wastewater, the preheated desulfurization wastewater flows to an inlet of a forced circulation pump, feed liquid is driven by the pressure of a forced circulation pump to enter a heater, the desulfurization wastewater is heated, evaporated and concentrated in the heater, and when the density of a densimeter arranged in a vapor-liquid separator reaches a set value, part of concentrated liquid is discharged into a concentrated liquid collecting box; and the desulfurization wastewater is evaporated and concentrated, then the concentrated solution is evaporated and dried by an evaporation drying tower, salt particles generated by drying enter a dust remover, and the system has the characteristics of short process flow, high concentrating ratio, no scaling in long-time stable operation, avoidance of auxiliary dosing, capability of recovering fresh water, diversification of heat sources and the like.

Description

technical field [0001] The invention belongs to the technical field of industrial wastewater treatment, and in particular relates to a wastewater zero discharge system based on the integrated treatment of high-efficiency concentration and spray drying. Background technique [0002] At present, thermal power plants adopt "limestone-gypsum wet flue gas desulfurization technology", which has become the most widely used desulfurization technology in thermal power plants at home and abroad, but desulfurization wastewater will inevitably be discharged during this process. The water quality of desulfurization wastewater is generally acidic (pH 4~6), containing a large amount of suspended solids, ammonia nitrogen and heavy metal pollutants, as well as Ca2+, Mg2+, F-, SO42-, Cl-, etc. The high concentration of sulfate in desulfurization wastewater is directly discharged When it enters the environmental water body, it will diffuse to the sediment layer, resulting in the formation of m...

AI Technical Summary

Problems solved by technology

The multi-effect flash evaporation system is used as the waste water concentration process, and steam is used as the heat source. The consumption of steam is relatively large, and the operating cost is very high. The drying section in the current process needs to separate the solid and liquid of the slurry produced by the concentration process. After separation, the upper The clear liquid enters the spray drying system, and the separated high-concentration salt slurry is dehydrated. Such a process is not only lengthy and complicated, but also needs to be equipped with auxiliary dosing systems and solid waste disposal devices.

Images