Reduction and reclamation recycled water reuse zero emission treating technology

Abstract

The invention discloses a reduction and reclamation recycled water reuse zero emission treating technology. The reduction and reclamation recycled water reuse zero emission treating technology comprises the steps that firstly, softening pretreatment is carried out on raw water waste water, and it is achieved that the concentration of calcium and magnesium ions is smaller than 100 mg / l, and the total hardness is smaller than 200 ml / l; secondly, outlet water enters a roll type RO membrane device to carry out first-time separation and concentration, and produced water of the outlet water is collected and reused; thirdly, concentration solution outlet water of the roll type RO membrane device enters a SuperRo system to carry out second-time concentration, evaporation condensate of the concentration solution outlet water is collected and reused, and the residual solid is transported out to be treated or treated in a landfill mode. An existing recycled water recycling technology is improved based on the special membrane technology, two times of concentration is carried out on biochemical outlet water through the roll type RO membrane device and the SuperRo system, the water producing efficiency is greatly improved, the treatment difficulty of an evaporation system is also lowered due to the fact that the concentration of the outlet water concentration liquid is increased, and the operation cost of all procedures is effectively reduced.

Description

technical field [0001] The invention relates to the technical field of sewage treatment, in particular to a zero-discharge treatment process for water reduction and resource recovery. Background technique [0002] SL368-2006 "Water Quality Standards for Reclaimed Water" stipulates various indicators for the use of reclaimed water. In addition to the conventional COD, chroma, SS and other indicators, there are also indicators for TDS. [0003] Conventional biochemical + physicochemical treatment can reduce CODcr and ammonia nitrogen and other indicators in sewage to a certain extent, but cannot remove soluble salts in sewage. If this kind of water is reused in production, even if the initial salinity index can meet the reuse requirements, as the number of recycling cycles increases, the accumulation of salt cannot meet the quality requirements of the reused water. [0004] Therefore, in order to fundamentally realize the reuse of reclaimed water and zero discharge, in additi...

AI Technical Summary

Problems solved by technology

[0008] 1. Some refractory organic substances remain, generally CODCr is 100~500mg / L;

[0009] 2. It has been treated by biochemistry + physicochemical treatment, and its reproducibility is poor;

[0010] 3. Introduce foreign substances in some sections of routine processing, and the salt content is high

[0011] The structural characteristics of the coil type reverse osmosis, although it has excellent desalination effect, but the anti-pollution is not high and the operating pressure is limited. For ordinary reclaimed water, after a relatively harsh pretreatment, the recovery rate can only reach 55%~65%. , that is, the remaining 35%~45% of the concentrate

In order to achieve zero discharge, the remaining concentrated liquid needs to be evaporated, and the amount of evaporation is relatively large.

[0012] Disadvantages of the evaporation process: high investment (20,000 yuan / ton of water, materials above duplex steel), high energy consumption (60 yuan / ton of water

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