System and method for comprehensive treatment of thermal power plant wastewater and recovery of chemical resources

Abstract

The invention discloses a thermal power plant waste water comprehensive treatment and chemical resource recovery system and method, comprising a conventional desulfurization waste water treatment system outlet pipe, regenerated high-salt waste water pipe, ammonia area waste water pipe, first sodium hydroxide dosing device, phosphate Dosing device, crystallization reactor, second sodium hydroxide dosing device, coagulant dosing device, reaction tank, first sedimentation tank, carbon dioxide absorption tower, flue gas bypass after desulfurization tower and chimney. The invention can effectively comprehensively treat waste water with high ammonia nitrogen and high hardness produced by thermal power plants, and has simple operation, low cost and good effluent quality.

Description

technical field [0001] The invention relates to a recovery system and method, in particular to a system and method for comprehensive treatment of thermal power plant waste water and recovery of chemical resources. Background technique [0002] Ammonia nitrogen is the main pollutant in water bodies. A high content of ammonia nitrogen will cause eutrophication of surface water, which is mainly manifested in the proliferation of aquatic plants, blue-green algae and other organisms, excessive consumption of dissolved oxygen in water, seriously affecting water quality, and causing aquatic organisms such as fish to be deficient. Oxygen death, therefore, in order to protect the ecological environment and reduce water pollution, the country requires ammonia nitrogen-containing wastewater to meet the first-level standard of the "Comprehensive Wastewater Discharge Standard" (GB8978-1996, ρ(NH 3 -N)≤15mg / L) before it can be discharged. The common high-ammonia-nitrogen wastewater in th...

AI Technical Summary

Problems solved by technology

The commonly used chemical softening method is to add chemical agents such as calcium hydroxide, sodium hydroxide, and sodium carbonate to make calcium and magnesium form mixed sediments such as calcium sulfate, calcium carbonate, and magnesium hydroxide, which are discharged from the power plant in the form of waste chemical sludge. The cost of chemical agents added is high, and the operating cost of the treatment system is high

Images