Urgent issue: advanced treatment of coking wastewater!
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I would like to consult experts: my factory plans to install a system for advanced treatment of coking wastewater, with the treated water intended to be reused as circulating water. The required quality parameters are COD ≤ 20 mg/L and ammonia nitrogen ≤ 5 mg/L. What are the main treatment processes currently used in China for such advanced treatment? Which manufacturers are involved? How is the processing effect? Thank you!
What is the COD level of coking wastewater after secondary treatment?
This post was last edited by qazxsw119 on 2012-2-17 at 14:34; it’s too heavy. Please delete it, moderator. Membrane manufacturers have developed pollution-resistant reverse osmosis membranes for industrial wastewater, but in practical applications, to ensure the safety of the membrane system, the COD concentration of the wastewater entering the reverse osmosis system is usually kept between 20 and 50 mg/L. In contrast, the COD level of the wastewater in the two approaches mentioned above is around 250 mg/L. Therefore, the key to the stable operation of the membrane system lies in effective and consistent pretreatment. Methods such as flocculation sedimentation and Fenton’s reagent introduce large amounts of iron ions and sulfate ions into wastewater, thereby exacerbating contamination and scaling in membrane systems; hence they should not be used in large quantities. On the other hand, the investment and costs associated with using advanced oxidation methods are too high. It is therefore recommended to first use methods like coagulation sedimentation to keep the COD level in wastewater at 100–150 mg/L, and then apply advanced oxidation techniques (ozone oxidation, electrochemical oxidation, wet catalytic oxidation) as well as activated carbon adsorption to carry out further treatment of the wastewater before it enters the membrane system.
Technologies for treating coking wastewater can include methods such as the A/O process and the SBR process. Industrial A/O biological nitrogen removal systems can be used to reduce the CODcr level in the effluent; the sequencing batch SBR (Sequencing Batch Reactor) treatment technique for coking wastewater is also a viable option, which the original poster can consider.
It depends specifically on your current water quality, the existing process, and the site conditions. We can provide services :)