Desulfurization wastewater treatment method and system

Abstract

The invention discloses a desulfurization wastewater treatment method and system. The desulfurization wastewater treatment method comprises the following steps: firstly, an electrochemical treatment method is adopted to remove suspended solids, heavy metals and COD in desulfurization wastewater, then the desulfurization wastewater is concentrated by a reverse osmosis treatment process, produced water enters a production process segment of a power plant to be reused, concentrated water passes through an electrolytic chlorination system, the content of chloride ions in the water is greatly reduced, and finally, chlorine salt in the concentrated water is converted into pypocholoride. Pypocholoride obtained by the desulfurization wastewater treatment method has a strong bactericidal function and can serve as a bactericide of a circulating water treatment and membrane treatment system of the power plant, so that the recycling rate of a power plant water system is improved, and the water taking cost and the production cost of the power plant are lowered.

Description

technical field [0001] The invention relates to the field of desulfurization wastewater treatment in thermal power plants, in particular to a desulfurization wastewater treatment method and system. Background technique [0002] There are mainly two solutions in the prior art: [0003] Option 1 Desulfurization wastewater adopts flocculation precipitation + softening + concentration + evaporation + crystallization [0004] Existing problems: [0005] 1. The equipment covers a large area, and the construction investment is very high. The investment per ton of water is 3.5 million to 4 million yuan per ton of water; [0006] 2. The chemicals and energy consumption are high, resulting in high operation and maintenance costs, which are about 300 yuan / ton of water; [0007] 3. The disposal cost of the mixed salt of the evaporation and crystallization product is high; [0008] 3. The market value of sodium chloride and sodium sulfate produced by salt division is low, and it is d...

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Problems solved by technology

[0005] 1. The equipment covers a large area, and the construction investment is very high. The investment per ton of water is 3.5 million to 4 million yuan per ton of water;

[0006] 2. The chemicals and energy consumption are high, resulting in high operation and maintenance costs, which are about 300 yuan / ton of water;

[0007] 3. The disposal cost of the mixed salt of the evaporation and crystallization product is high;

[0008] 3. The market value of sodium chloride and sodium sulfate produced by salt division is low, and it is difficult to recover the cost

[0009] 4. The thermal power plant does not have a license for industrial salt production, so it needs to consider outsourcing or dispose of it as solid waste;

[0012] 1. In the case of improper design, the fouling of the flue will be serious; the flow field in the flue is complex, and if the design is improper, the fly ash will have an adhesion effect and adhere to the container wall, and the chloride ions will cause serious corrosion to the exposed steel components ;

[0013] 2. The design of the atomizing nozzle and the arrangement of the nozzle have a great influence on the evaporation effect, and the concentration of desulfurization wastewater and the size of the atomized droplets directly affect the evaporation effect;

[0014] 3. Increase the burden on the dust collector and reduce the coal combustion efficiency; there are high requirements for the pretreatment of desulfurization wastewater, and the amount of SS in the water has a great impact on the flue evaporation swirl atomizer;

[0016] 5. The evaporation of desulfurization wastewater reduces the temperature of the flue gas, reduces the combustion efficiency of the boiler, and increases the coal consumption;

[0017] 6. The desulfurization wastewater is not treated and cannot be reused, which does not conform to the national policy of energy saving and water saving

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