Electric flocculation method and device for recovering and processing desulfurized wastewater

Abstract

The invention discloses electric flocculation method and device for recovering and processing desulfurized wastewater. The electric flocculation method for recovering and processing desulfurized wastewater comprises the following steps of: collecting desulfurized wastewater to enter an electric flocculation reactor, then, carrying out solid-liquid separation, recovering the separated clear effluent water in a clinker-flushing system of an electric power plant or directly discharging the separated clear effluent water, conveying the sludge to dewater in a mud-processing system, and returning the effluent water of the mud-processing system to a water intake system. Compared with the prior art, the electric flocculation technology is adopted to substitute a complicated chemical method for recovering and processing the desulfurized wastewater, can effectively remove pollutants in the wastewater, reaches a heavy metal processing rate up to 95-99 percent, a chlorine-processing rate over 80 percent and removal rates of ammonian, and the like over 90 percent, greatly shortens the processing time, improves the processing efficiency and saves the investment cost. Moreover, the electric flocculation processing device has small size, extremely small floor occupation, good environmental-protection performance and low cost without additional flocculating agents.

Description

technical field [0001] Technical field: The present invention relates to a method and device for electrocoagulation recovery and treatment of desulfurization wastewater, which belongs to the technical field of wastewater treatment. Background technique [0002] Flue gas desulfurization is currently the only large-scale commercial application of desulfurization in the world, and it is the main technical means to control sulfur dioxide pollution. Limestone-gypsum method is currently the most widely used flue gas desulfurization method, which can efficiently remove sulfur dioxide in flue gas. The wastewater generated from the boiler flue gas wet desulfurization (limestone / gypsum method) process mainly comes from the gypsum dehydration and cleaning system. The impurities contained in wastewater mainly include suspended solids, supersaturated sulfite, sulfate and heavy metals, many of which are the first category of pollutants that are strictly controlled in the national environ...

AI Technical Summary

Problems solved by technology

For example, some power plants in the United States use the flue gap between the electrostatic precipitator and the air heater to heat and evaporate the desulfurization wastewater. The wastewater evaporates into water vapor and enters the flue, and the solid particles are removed by the electrostatic precipitator. Increased flue gas humidity or HCl content will cause low-temperature corrosion to the electrostatic precipitator. In addition, too much desulfurization wastewater may affect the efficiency of the electrostatic precipitator. There is no precedent for this scheme to be put into operation in China.

Concentration evaporation and crystallization technology is based on the waste water treatment and material recovery equipment system method of GE Energy Company in other systems. Its investment is very high. The investment of 20 tons / hour desulfurization waste water equipment needs about 100 million yuan. So far, there is no similar Project running example

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