A near-zero discharge treatment system and method for high-concentration organic wastewater and sludge

Abstract

The invention discloses a near zero emission treatment system and method for high-concentration organic wastewater and sludge, and belongs to the technical field of chemical engineering and environment protection. The supercritical water oxidation technology is used as the core, waste water and sludge are ground through a sludge homogeneity pump first and are then pressurized through a high-pressure plunger pump and conveyed to a subsequent pipeline to be preheated and mixed with oxygen, and supercritical water oxidation reaction is conducted in a reactor. Fluid obtained after reaction sequentially passes through a self-washing filter and a gas-liquid separator after being subjected to pressure reduction of a pressure reduction device so that insoluble solid and gas can be separated, the fluid then crystallizes through the mechanical vapor recompression (MVR) technology, soluble salt crystallization is conducted, and near zero emission of fed materials is achieved. Meanwhile, the conventional water treatment technologies (such as coagulating sedimentation, the membrane biology technology and the membrane technology) are used for assisting the SCWO technology, running parameters of the SCWO reactor are appropriately decreased, a part of residual COD is processed through the conventional water treatment technology, and the running cost is effectively reduced.

Description

technical field [0001] The invention belongs to the technical field of chemical industry and environmental protection, and specifically relates to a near-zero discharge treatment system and method for high-concentration organic wastewater and sludge with supercritical water oxidation technology as the core. Background technique [0002] Under normal circumstances, water exists in three common states of steam, liquid water and ice. Liquid water is a polar solvent whose density hardly changes with the increase of pressure. It can dissolve most electrolytes including salts. And most organic matter is slightly soluble or insoluble. Supercritical water refers to water in a special state where the temperature and pressure are higher than its critical point (374.15°C, 22.1MPa). The properties of supercritical water will change greatly, and its density, dielectric constant, diffusion coefficient and thermal conductivity are different from ordinary water. Moreover, the solubility o...

AI Technical Summary

Problems solved by technology

[0012] In order to overcome the above-mentioned defects in the prior art, the object of the present invention is to provide a near-zero discharge treatment system and method for high-concentration organic wastewater and sludge. Solve the problem of salt deposition, improve economy and achieve near zero discharge

Images