Transformation Of Coal To Olefins Wastewater Treatment Process

In recent years, the rapid development of coal chemical enterprises brings aboutthe rapid economic development in western China. However, the coal chemicalindustry enterprise will bring about a lot of organic wastewater, with the complexcompliment and the poor biodegradability, it is a typical of the toxic and harmfulindustrial wastewater, if not properly treated, it will not only pollute the environment,but also do harm to the enterprise image. In addition to factors as location, droughtand water shortage in the region, sustainable the development of this restricted coalchemical enterprises in the region. Therefore, it is particularly important to develop aeconomical and effective treatment of the coal chemical industry wastewater at thisstage.In this paper, we use the A/O-MBR-RO process to upgrade the original CASTprocess, to get the coal to olefins wastewater depth treatment and reused. Thewastewater is firstly handled by A/O processing, required to achieve “IntegratedWastewater Discharge Standard (GB8978-1996)” in the secondary emissionstandards.Then, the wastewater is deeply treated by the MBR+RO system, to meetthe requirements index of reclaimed water in "industrial circulating cooling watertreatment design specification"(GB50050-2007). In the pilot test, considering thepresent conditions and treatment of actual production, we mainly to carry out the A/Oprocess several key factors on the effect of the degradation of pollutants, such asnitrification liquid reflux ratio, dissolved oxygen, temperature of wastewater;membrane flux and the concentration of sludge in MBR system on membrane foulinganalysis; and the water inlet temperature and pressure RO system for water productionand the desalination rate influence and analysis, all those studies can provide areliable scientific basis for the technological transformation of key operatingparameters determinedUsing the A/O-MBR-RO combined process to deal with the coal to olefinswastewater, the final effect of the pilot test results are as follows: the effluent CODCrare at an average of5.9mg/L, the average removal rate was99.3%; the effluentammonia was0.52mg/L, the average removal rate was99.4%; Out of the water thereis no detected good degree of SS and turbidity of effluent; the water conductivity islower than75us\/cm, the hardness is less than17.5mg/L. The effluent quality meetsthe "code for design of industrial circulating cooling water treatment"(GB50050-2007) index of water quality of reclaimed water in requirementsThe stability of the pilot system, confirmed that the A/O-MBR-RO process hasobvious advantages in handling with coal chemical industry wastewater, the effluentquality can meet the standard of the corresponding recycling water.It can providetechnical support for wastewater treatment process and water recycling technologyand promote the sustainable development of enterprises.