Treating technology for chemical RO concentrated water

Abstract

The invention relates to a treating technology for reverse osmosis (RO) concentrated water after water reuse in a chemical membrane method. The technology comprises the steps that firstly, matter such as lime or sodium hydroxide which is alkaline in an aqueous solution is put in RO concentrated water effluent to enable the pH of the concentrated water to be about 10-11.5; secondly, flocculent precipitation is performed in a mechanical accelerating clarification tank to reduce the hardness of the wastewater and remove heavy metal and reducing metal ions; thirdly, the effluent directly enters an ozone reaction tank after the RO concentrated water passes through the mechanical accelerating clarification tank, and then ozone tank effluent enters a biological activated carbon filter bed device to further remove pollutants and turbidity in the RO concentrated water, so that the wastewater effluent can meet the national primary standard (the CODcr is smaller than or equal to 60 mg / L). According to the treating technology, further treatment is performed on the concentrated water generated after the water is reused through the front stage of biochemistry, ultrafiltration and reverse osmosis for the production wastewater in chemical industry to achieve the purpose of direct discharge, therefore, the pollution treatment ability of enterprises can be improved, the total pollutant discharge amount is reduced, and the effects of energy conservation and emission reduction, clean production and sustainable development are achieved.

Description

technical field [0001] The invention relates to a chemical RO concentrated water treatment technology, in particular to a process for removing hardness of aromatic hydrocarbon chemical wastewater RO concentrated wastewater and COD degradation to meet the standard discharge. Background technique [0002] After the chemical wastewater is reused in the membrane process, the COD of the reverse osmosis concentrated water is usually 200-300mg / L, and most of them are the residual refractory organic matter after the previous biochemical treatment; the salt concentration of the concentrated water is 6,000-10,000mg / L, and Wastewater contains more calcium and magnesium hardness and highly reducing metal ions (such as Fe 2+ ,Mn 2+ ), highly toxic and harmful, and difficult to treat wastewater. [0003] In the existing treatment technology, for the reverse osmosis concentrated water (RO concentrated water) with high salt content and difficult biodegradation after the water reuse of che...

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Problems solved by technology

[0003] In the existing treatment technology, for the reverse osmosis concentrated water (RO concentrated water) with high salt content and difficult biodegradation after the water reuse of chemical wastewater membrane method, the treatment methods include direct discharge to the ocean and other places (only applicable to coastal areas) and Evaporation ponds (applicable to inland areas, but with a large area and strict anti-seepage requirements), others such as using ozone + hydrogen peroxide strong oxidant to treat RO concentrated water under photocatalysis, using iron-carbon micro-electrolysis followed by PAM flocculation treatment or Directly adopt electro-adsorption technology to treat RO concentrated water, or directly adopt multi-effect evaporation for disposal (this method has high treatment cost)

[0004] Most of the above technologies are in the research stage, and the effluent water quality is unstable, the cost of the treatment process is high, or the effluent cannot meet the requirements of direct discharge, etc.

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