| More attention on anaerobic treatment technologies, have been paid by industry for their process effluent treatment, since this technology with many advantages such as high pollution load, less occupied land area, lower operation cost and high stabilities of effluent load strikes as well. These technologies have widely been successfully applied for various types of industrial effluent treatment plants. Resource saving and environment protection have been recognized as the common two major topics worldwide, therefore, the technologies for industrial processing have been forced toward the directions of high-efficiency utilization of resource, water-saving and energy-saving, lowering pollutants and so on. In this case, the quantities of effluent have been decreased significantly, on other hand, the concentration of effluent increased obviously, which leading to difficulties of handling and treatment. For instance, measures of water-saving have been taken for new high-yield pulping process causes the increase of its effluent concentration with COD consistency of higher than 10 thousands mg/L, which brought troubles for stable operation of traditional anaerobic reactor. Development and design of new-type high-efficiency bioreactor for this purpose have been interested by scientist in the field of effluent treatment.Two programmes of high efficiency bioreactor (I-compact baffled high efficiency bioreactor and II-composite module high efficiency bioreactor) were designed with the two-phase anaerobic digestion principle and staged multi-phase anaerobic technology (SMPA) being concerned and study on the third generation of anaerobic bioreactor (UBF, EGSB, IC). Comparing with the two programmes of high efficiency bioreactor, the compact baffled HEB was accepted and produced ultimately as it can meet the laboratory research need ,its more advantage feature, such as the multi-function, modular, can be adjusted, broad adaptability, is also be considered.I-compact baffled high efficiency bioreactor: cylinder-shaped, which being divided into three areas - acidogenic phase area, baffled area, and methanogenic phase area. Water flows were overflowing, pack within the flow and internal circulation. Volume of acidogenic phase reactor is 1.6 L, volume can be changed conveniently by replacing acidogenic phase reactor dueing to the thread connection, Volume of baffled area is 4.1 L, Volume of methanogenic phase reactor is 15 L. The high efficiency bioreactor has compact structure and good strength. II-composite module high efficiency bioreactor: designed with modular, it has a universal main body, many functions can be realized with its different combination in accordance with the purpose of testing. Its diameter is 40 mm, the ratio height to diameter is adjustable, the precipitation zone is adjustable and water distribution methods are adjustable.Pollution load of effluent of poplar P-RC APMP process were analyzed firstly, the results are: effluent quantities are 21.758 m3 per ton pulp (to dry pulp ), pH value is 6.01, COD is 4205 mg/L, COD load is 91.49 kg / t pulp (to dry pulp), BOD is 1794 mg/L, BOD load is 39.03 kg / t pulp (to dry pulp).In order to study the properties of high efficiency bioreactor, effluent of poplar P-RC APMP process was treated with high efficiency bioreactor and UASB, effect of high efficiency bioreactor is better than UASB. After one months continues running, the average COD removal rate reached 80.9% and the average BOD removal rate reached 85.4% when volume load rate was 5 kg COD/(m3 ? d) and reflux ratio was 20:1.Some parameters affecting operation of high efficiency bioreactor (pH, temperature and volume load rate) were studied, it shows:①high efficiency bioreactor has a certain buffer to pH than UASB,②COD removal rate decreases with the decrease of temperature from 38℃to 9℃, which of high efficiency bioreactor is greater than UASB.③COD removal rate decreases with the increase of Volume load rate when more than 10 kg COD/(m3·d), COD removal rate downward trend intensified when more than 30 kg COD/(m3·d).Experiments verify that the design of new high efficiency bioreactor on the poplar P-RC APMP effluent has a good effect.
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