Abstract
Domestic wastewater quality varies greatly with the property of decentralized source pollution. Through the monitoring and comparative research it was clear that the decentralized domestic wastewater quality in China is usually as follows: CODcr: 200~1000mg/l, BOD5: 100~500mg/l, SS: 100~500mg/l, TN: 20~90mg/l and TP: 3~15mg/l. Ratio of BOD5 to CODcr is 0.4~0.6, showing high biodegradability. A verification study has been conducted by the advanced Johkasou of cycling anaerobic filter bed-biofiltration process to determine the effect of different pollutant concentration on the biological treatment efficiency. By these examinations fundamental methods of evaluation of Johkasou performance in China have been established on the whole.
