Development on High Rate Treatment Process of Upflow Anaerobic Sludge Blanket (UASB) Reactor.

以实际生活污水和淀粉厂工业废水为试验对象，研究了上流式厌氧污泥床（UASB）反应器处理低浓度废水的技术可行性。通过对某工业废水的连续流处理实验，得到以下结果：1.反应器可以在高负荷<cr>（25 kg/m^3）下运行。d在35 ℃左右的温度下。溶解性COD_（Cr）<cr>和BOD（以进水总COD_<cr>（Cr）和出水溶解性COD_（Cr）<cr>和BOD计）的去除率均达到90%以上.总COD<cr>去除率（以进水总COD<cr>和出水总COD计<cr>）随COD负荷的增加而降低<cr>，SS去除率从50%（COD<cr>负荷为2.5kg/m^3.在<cr>25 ~ 13 ℃、HRT为4.7小时的条件下，对生活污水进行了处理。总COD<cr>、固体COD<cr>和BOD的去除率分别达到70%、80%和85%，总COD和可溶性COD的去除率与进水强度有关，与温度无关。另一方面，颗粒有机物在进水中被有效地去除到污泥床截留。温度对床层中截留有机物的水解率有显著影响，在25 ℃时，58%的截留颗粒有机物液化，而在13 ℃时只有33%的截留颗粒有机物液化。此外，用扫描电镜观察以生活污水为原料的污泥的形态结构发现，颗粒有机物有部分裂解和自溶的趋势，尽管整体上仍保持粒状形式。UASB反应器在处理低浓度废水时，需要维持20 ℃以上的温度。

The technical feasibility of treatment of low strength wastewater by upflow anaerobic sludge blanket(UASB)reactor was experimentally investigated using an actual domestic wastewater and industrial wastewater of starch manufacturing factory. The results obtained from continuous flow experiment at treatment of an industrial wastewater are as followings :l. It is possible to operate the reactor at high COD_<cr> loading rate, 25kg/m^3. d at the temperature around 35 ﾟC.2. The removal efficiencies of soluble COD_<cr> and BOD (based on influent total COD_<cr>, BOD and effluent soluble COD_<cr>, BOD) both achieved to be 90%.3. Total COD_<cr> removal efficiency (based on influent total COD_<cr> and effluet total COD_<cr>) decreased with increasing of COD_<cr> loading rate.Also, SS removal rate decreased from 50% (COD_<cr> loading rate : 2.5kg/m^3. d) to 17% (COD_<cr> loading rate : 22kg/m^3d).The results obtained using a domestic wastewater at a HRT of 4.7 hrs in the temperature range of 25 to 13ﾟC are as follows. The removal efficiency of total COD_<cr>, solid COD_<cr> and BOD achieved to be 70%, 80% and 85%, respectively.The removal rates of total COD and soluble COD depend on the influent strength, but not on the temperature. On the other hand, the particulate organic matters in the influent were effectively removed by entrapment into the sludge bed. The hydrolysis rate of the entrapped organics within bed was significantly affected by temperature, that is, 58% of the entrapped particulate organics was liquefied at 25ﾟC, whereas only 33% at 13ﾟC.Furthermore, observation of morphological structure of the sludge fed on the domestic wastewater by scanning electron microscopy revealed that the granules had a tendency to be partly cracked and to be in a state of autolysis, even though remaining granular forms as a whole. It is necessary to maintain UASB reactor at the temperature above 20ﾟC for treatment of low strength wastewater.