System and method for treating desulfurization wastewater concentrated solution

Abstract

The invention relates to a system and method for treating a desulfurization wastewater concentrated solution. The system for treating a desulfurization wastewater concentrated solution comprises a boiler, an air preheater, an electric dust collector, a desulfurizing tower, a concentrator, a concentration pump and a treating tower which are sequentially connected, wherein the desulfurizing tower is connected with an external chimney. The method for treating a desulfurization wastewater concentrated solution comprises the following steps: 1) turning on a bypass gas inlet switch to guide bypass flue gas to enter the treating tower; 2) starting an upward spray gun and a downward spray gun, thereby forming a misty concentrated solution in the treating tower; 3) when the flue gas temperature at the bypass flue outlet is lower than the threshold, opening a three-way valve so that the flue gas returns to a pipeline at the front ends of the boiler and air preheater; 4) when the flue gas temperature at the bypass flue outflow is higher than the threshold, opening the three-way valve so that the flue gas enters the pipeline from the air preheater to the electric dust collector; and 5) sending the flue gas in the step 4) into the electric dust collector, discharging through an electric dust collection port.

Description

technical field [0001] The invention discloses and belongs to the field of environmental engineering, and in particular relates to a system and method for treating concentrated liquid of desulfurization wastewater. Background technique [0002] The newly promulgated "National Environmental Protection "Eleventh Five-Year" Plan" clearly stipulates to promote the recycling of waste water in the power industry and strive to achieve zero discharge of waste water. After 2013, national environmental protection departments at all levels clearly required that desulfurization wastewater from coal-fired power plants achieve zero discharge. [0003] The origin of desulfurization wastewater is to maintain the balance of substances in the slurry circulation system of the desulfurization unit, prevent the soluble part in the flue gas, that is, the chlorine concentration from exceeding the specified value, and ensure the quality of gypsum. A certain amount of wastewater must be discharged f...

AI Technical Summary

Problems solved by technology

This method has been found in domestic and foreign case practice. Due to the high content of various salts in the concentrated liquid, the evaporation and crystallization are too fast, which often causes nozzle blockage, making it difficult for the system to work continuously and requires a lot of maintenance.

Especially when the flue gas volume changes with the boiler load adjustment, the concentrated liquid cannot be completely evaporated, and the mixture of moisture and high-concentration dust can block more than half of the flue in a short time, greatly affecting the resistance balance of the entire system, and thus affecting the production of the power plant

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