| Nowadays global water environment quality is facing severe situation. The total drainage exceeds far the water environment capacity. In China, The paper manufacturing wastewater drainage volume takes the second place of all industrial departments, only less than the chemical industry's outflow. And its COD discharge consists one third of the national industrial discharge. MBR processing is a new water treatment and reuse technology, which has advantages over non-degradable organic wastewater in high concentration. In the study, hydrolysis plus anaerobic membrane bio-reactor was chosen to treat paper manufacturing middle wastewater mainly produced in the process of washing, screening and blanching. We hope that the study could provide some supports both theoretically and technically to the papermaking wastewater treatment.When the experiment started the HRTs of hydrolyzing tank and UASB were both very high. Experiments also proved that the system could be started when HRT relatively low. During this experiment, the highest capacity load of UASB reached 3.6KgCOD/(m3.d), but the removal rate of reactors kept 50% or so, while its VFA, alkalinity and pH value stayed normal. So papermaking middle wastewater can be treated with high loads.In this experience, the use of hydrolyzing tank was aiming to improve the degradability of the wastewater, preparing for next stage treatment. But the acidification of the hydrolyzing tank performed not well through the experiment periods, with its pH=7 or so, and further research must be done to reveal the reason.The activity of the sludge in the UASB stayed low, and the VSS/SS was a little higher than 0.3, but the gas-generation performed well, neither did inhibition happen. There was no granular sludge produced, possibly because of the low removal rate, lack of gas-generation, and a low up flow velocity.
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