Advanced treatment method and device of coking wastewater

Abstract

The invention discloses an advanced treatment method and device of coking wastewater and relates to the technical field of coking wastewater treatment. The advanced treatment method of coking wastewater comprises steps as follows: (1) treating the coking wastewater with a biochemical method; (2) adding a gangue-based inorganic polymer coagulant and performing efficient coagulation and filtration;(3) performing adsorption with reproducible filler, and enabling a desorption solution to flow back to a biochemical device for biochemical treatment after microelectrolysis and Fenton treatment; (4)sequentially performing ultrafiltration, nanofiltration and reverse osmosis treatment and treating reverse-osmosis high-concentration brine water through membrane distillation and crystalizing coupling. A series of environmental protection problems caused by drainage of the coking wastewater are solved, and the method and the device have very remarkable social and environmental benefits, also haveprofound significance in survival and sustainable development of the coking industry, improvement of the ecological environment and water resource saving and are suitable for large-scale popularization in the coking industry.

Description

technical field [0001] The invention relates to the technical field of coking wastewater treatment, in particular to a coking wastewater advanced treatment method and device. Background technique [0002] Shanxi is a major province of coke production. In 2015, the coke output was 80.34 million tons, accounting for about 20% of the country's total output. Coke production, especially coal dry distillation and gas cooling and purification process, will produce a large amount of coking wastewater, with an average of about 0.5-1.0m per ton of coke 3 of coking wastewater. These wastewaters contain high concentrations of phenols, cyanides, thiocyanides, and ammonia nitrogen, as well as oils that are difficult to biodegrade, heterocyclic compounds such as pyridine, and polycyclic aromatic compounds such as biphenyl, which are highly toxic and difficult to treat. Difficulties in the field of industrial wastewater treatment. [0003] At present, the treatment of coking wastewater u...

AI Technical Summary

Problems solved by technology

Because the cost of coagulation and sedimentation is relatively low, it is widely used in the advanced treatment of coking wastewater. However, due to the strong polarity of the remaining organic matter and many chromophoric groups, the conventional coagulation and sedimentation technology has the disadvantages of large amount of flocculant, COD and chromaticity. Low removal efficiency and other issues make it difficult to reach the standard after treatment

The effect of the activated carbon adsorption method is good, but the main problem is that the treatment effect will gradually deteriorate with the extension of time, and it needs to be replaced after the adsorption is saturated. The operation is difficult and the operation cost is high. At present, the regeneration of activated carbon is still difficult and basically impossible.

Most advanced oxidation technologies (such as electrochemical oxidation, photocatalysis, etc.) have high treatment costs and are difficult to engineer; advanced oxidation technologies such as Fenton and ozone oxidation have high maturity, low technical risk, small investment, and good treatment effect, but Need to add hydrogen peroxide with high cost, and add a lot of acid and alkali to introduce a lot of salts, which is not conducive to wastewater reuse; direct ozone oxidation, low ozone utilization rate, high cost, and unsatisfactory treatment effect

Among the membrane separation technologies, nanofiltration and reverse osmosis have a high removal rate of salt and organic matter, and can prepare desalted water, but when they are directly applied to coking wastewater, membrane pollution is serious, membrane life is low, investment and treatment costs are high, and pre-membrane pre-treatment is necessary. At the same time, the way out of the concentrated water becomes a problem

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