A process for purification of desulfurization sewage in a coal-fired power plant

Abstract

Belonging to the technical field of waste treatment, the invention in particular relates to a purification process for coal fired power plant desulphurization sewage. The method comprises the steps of: 1. adjusting the pH value to alkaline; 2. adding a chelating agent and fully stirring the materials till no generation of floc; 3. adding inorganic high molecular polymer magnetic powder, and fully stirring the materials; 4. adding an organic high molecular polymer, and fully stirring the materials; 5. conducting solid-liquid separation until all the flocs settle, and discharging the lower sediment; and 6. adjusting the pH value to neutral. The process provided by the invention adopts simple system and steps to completely and effectively remove the neutral salt, suspended solids, fluorides, sulfides, heavy metal ions and other harmful pollutants from the sewage, and has the characteristics of low cost and simple operation, etc.

Description

Technical field [0001] The invention belongs to the technical field of waste treatment, and in particular relates to a process for purifying desulfurization sewage from coal-fired power plants. Background technique [0002] There are three types of desulfurization technology, namely, pre-combustion desulfurization, in-combustion desulfurization, and post-combustion desulfurization. The third is a technology that is widely used in commercial applications in the world, and is divided into wet and dry methods according to the form of desulfurizer. , Semi-dry method; the most important technology in the wet method is the American wet limestone / lime method and the Japanese wet limestone / gypsum method. my country's power plant flue gas desulfurization method, especially thermal power plant boilers, is mostly limestone-gypsum (FGD) wet flue gas desulfurization. [0003] In the actual application of this technology, an absorbent (lime slurry) circulating washing system is required. The he...

AI Technical Summary

Problems solved by technology

It can be seen that its scope of application does not include desulfurization sewage from power plants. Since the types and contents of suspended solids, soluble solids, heavy metals and other substances in different types of sewage and the pH of the water are different, whether the magnetic flocculation technology is applicable It is difficult to predict how to choose flocculation agent, treatment steps and other conditions to improve the treatment effect in the treatment of power plant desulfurization sewage.