Introduction

Removal of COD from wastewater is a key technology urgently needed in the environmental protection market in China. Beijing Cycle Columbus Environmental Protection Technology Co., Ltd. has developed a comprehensive method to remove COD from oily raffinate effluent.

The technology contains several steps, such as pretreatment of wastewater to reduce the amount of suspended solid and suspended/emulsified/dispersed oil; adsorption treatment to remove dissolved oil; and advanced oxidation process to deeply remove COD in the wastewater. The COD level of the discharged water is less than 50 mg/L.

Features/Benefits

(1) The COD level of the discharged water is less than 50 mg/L, which meets the standard of “Integrated wastewater discharge standard” (CN-GB 8978-1996);

(2) The sorbents and solvents are easy to regenerate or recycle without any solid waste.

(3) The technology combines physical and chemical method, and the operation cost is less than $1.5 per ton of wastewater.

Application Status

The lab-scale and pilot-scale tests have been implemented in more than ten sites (e.g. Huayou Cobalt, Chaucsun Umicore, Ji’an Xintai Tech.), and the excellent performance is highly praised by the proprietors of cobalt-nickel and rare-earth processing industries.