Removal of COD in coking-plant wastewater by the moving-bed biofilm sequencing batch reactor process

摘要

The coking wastewater contains wide range of hydroxybenzene, phenols, mono-cyclic nitrogen-containing compounds, and most of the contaminants are non-biodegradable, which make the biological treatment results unsatisfied. In spite of conventional activated sludge treatment with A-A-O process can offers an efficient removal of NH4+-N and COD from the coking wastewater, this system still has some limitations, such as the high operating expense, poor tolerance to shock loading, poor settle-ability problem at high loading rates[1].