Cleaning Process Research of MVR High Concentration Salty Wastewater Treatment System

¹ School of Environmental Science and Engineering, Qilu University of Technology, Jinan, Shandong, China
² Water Technology Research Institute, A Agrochemical Company of Binzhou, Binzhou, Shandong, China

Abstract

A mechanical vapor re-compression (MVR) evaporation system for the treatment of the highly-concentrated inorganic salt wastewater was investigated, and its process characteristics were analyzed taking sodium chloride salt wastewater as the treated solution. In this paper, by adding “H₂O₂ oxidation + filter +flash evaporation + hot filter” technology on the basis of original traditional MVR treatment system, the optimum technological conditions were determined through the experiment: The pH value is 8.5; the oxidation time is 24.0h; H₂O₂ amount accounting for 1% of the total wastewater under the condition of outlet test MVR system respectively fell 88.5% and 90.1% than the traditional process of effluent COD and NH3-N removal rate. MVR system for the sodium chloride salt qualified rate was increased from 83.2% to 98.2%. On the other hand, this process avoided the highly-concentrated outside of mother liquor by flashing evaporation recycling volatile solvent; the optimization process results were found to be consistent with published practical industrial data. Compared with the new process MVR system, the operation load of MVR system was lower. Therefore, the system can be used to treat the highly-concentrated inorganic salt wastewater and save energy. Therefore, the cleaning process can achieve remarkable energy saving and consumption, and reduce the pollution and the pollution and environmental protection effect.