Recycling system and process for high salt-containing wastewater

Abstract

The invention discloses a recycling system and process for high salt-containing wastewater. The system comprises an adjusting tank, a clarifying and softening device, a filtering device, a nanofiltration device, a high-pressure reverse osmosis device, a reverse osmosis device and an evaporative crystallization device, wherein an aeration device, a stirring device and an auxiliary dosing system arearranged in the adjusting tank; the clarifying and softening device adopts a two-stage clarifying and softening process, and comprises a primary clarifying and softening tank and a secondary clarifying and softening tank; the filtering device adopts a double-medium filtering device; membrane elements of the high-pressure reverse osmosis device and the reverse osmosis device are arranged in a manner of one stage and two sections; pipe mixers are arranged at a water inlet of the primary clarifying and softening tank and a water inlet of the high-pressure reverse osmosis device. By means of thesystem or the process, the recovery rate of produced water reaches 90%, the recycling rate of salt in the wastewater reaches 85%, the amount of to-be-treated water entering the evaporative crystallization unit can be reduced by concentration, energy consumption of salt production with an evaporation heat method is greatly reduced, investment and operating costs are saved, and the system and the process are environmentally friendly and resource-saving.

Description

Technical field [0001] The invention belongs to the field of water treatment, and specifically relates to a resource treatment system and process for high-salinity wastewater. Background technique [0002] With the rapid development of my country's economy, industrial water consumption has surged. At the same time, the amount of wastewater produced is gradually increasing, which brings huge challenges to the current wastewater treatment and recycling technologies. For high-salinity wastewater, due to lack of technical and economic feasibility and reliability, most of them adopt dilution efflux methods. This method not only can not really reduce the total discharge of pollutants, but also causes the waste of fresh water, especially the discharge of high-salinity wastewater, which is bound to cause the mineralization of freshwater water resources and soil alkalization. Therefore, how to develop economical and effective high-salinity wastewater desalination technology and promote ...

AI Technical Summary

Problems solved by technology

[0003] The earliest high-salt wastewater treatment method in foreign countries is the direct evaporation method, such as the MERRIMACK power plant in the United States, the Mayo power plant, etc., but this method consumes a lot of energy and is too economical.

A power plant in Huadong Huaneng, China, adopts reverse osmosis and evaporation technology to reduce consumption to a certain extent, but the solid waste generated still needs to be treated, which will inevitably bring expensive investment and operation costs, and cannot maximize the utilization of resources.

Images