An energy-saving coal chemical industry wastewater advanced treatment system and its treatment method

Abstract

The invention discloses an energy-saving coal chemical engineering wastewater deep treatment system and a treatment method thereof. The system comprises a forward osmosis (FO) membrane concentration device and a multi-effect evaporator, wherein the FO membrane concentration device comprises one or more stages of airtight FO membrane exchange boxes, a sucked solution recycling device and a clear water recovering device; the sucked solution recycling device is connected with the stages of airtight FO membrane exchange boxes through electrical valves respectively; the clear water recovering device is connected with the sucked solution recycling device; the stages of airtight FO membrane exchange boxes are connected through liquid discharge electrical valves in sequence and connected with a mother liquid incineration furnace through overrunning electrical valves. The method is characterized in that for high osmotic pressure characteristic of coal chemical engineering wastewater, water resources are recycled while the coal chemical engineering wastewater is efficiently concentrated to generate electrical energy by preparing a sucked solution with relatively good colligative properties and utilizing osmotic pressure difference caused by colligative property difference of the solution; the automatic interlocking control is realized in a running process and the running mode can be adjusted according to different water feeding conditions.

Description

technical field [0001] The invention relates to an advanced treatment system and method for coal chemical wastewater, belonging to the technical field of wastewater treatment. Background technique [0002] The so-called coal chemical industry is an industry in which coal is used as raw material and converted into gas, liquid, solid fuel and various chemical products through a series of chemical process reactions. [0003] my country's energy structure rich in coal, poor in oil, and low in gas determines the rapid development of the coal chemical industry, especially the new coal chemical industry. Traditional coal chemical industry generally refers to coal gasification, liquefaction, coking and tar processing, calcium carbide acetylene chemical industry, etc., and also includes the production of carbon materials and coal-based polymer materials using coal as raw materials. The new coal chemical industry is led by coal gasification, including coal-to-methanol, acetic acid, d...

AI Technical Summary

Problems solved by technology

However, it is not difficult to find that some methods are limited in their applicability due to their own disadvantages.

For example: the physical method does not completely degrade the pollutants, but only transfers them from one phase to another; the chemical method requires a large amount of chemical agents, which makes the operation cost high and it is difficult to promote on a large scale. secondary pollution

Biological treatment is relatively cheap and is currently widely used as a water treatment method. However, its limitations are: 1) slow degradation rate; 2) strong selectivity of bacterial action; 3) incomplete degradation may form Toxic intermediate products; 4) Some aromatic compounds are difficult to be degraded

AogatePR research pointed out that the treatment effect of some deep oxidation methods is not ideal. Even if the effect is ideal, the price is relatively expensive and it is difficult to promote

[0012] Chinese patent literature CN102211839A discloses "A Coal Chemical Wastewater Treatment Method", CN103880242A discloses "A Coal Chemical Wastewater Advanced Treatment Process", CN103466903A discloses "Using Microorganisms to Treat Coal Chemical Wastewater Method", CN103833175A discloses "Coal Chemical Complete Set of Wastewater Treatment Device", "A Coal Chemical Wastewater Treatment Process" disclosed by CN101560045, "Coal Chemical Wastewater Treatment Process" disclosed by CN102674634B, and "A Coal Chemical Wastewater Treatment Method" disclosed by CN101503267B are mostly improvements to conventional methods , the processing effect needs to be improved

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