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491.
The united membrane biological reactor(UMBR) was studied for the treatment of some simulate and municipal wastewater. The removal efficiency for COD and turbidity are greater than 80% and 99% respectively. Effluent COD is less than 100 mg/L while turbidity less than 5. The removal of LAS in bath wastewater is greater than 70%. In treatment of dinning-hall wastewater, removal of fatty oil is greater than 90%, and its concentration in effluent is less than 5 mg/L. The match of biological reactor and the membrane separation component were calculated. The stable performance of wastewater treatment can be maintained by the optimization of operation conditions and the eleanout of membranes. 相似文献
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隧道渗涌水量的随机模型预测 总被引:10,自引:0,他引:10
渗涌水问题是常见的隧道病害 ,是影响隧道正常使用 ,危及行车安全的重要因素。因此 ,科学地预测隧道涌水量大小 ,是制定最优防治水方案 ,确保安全通车的关键。笔者以大瑶山隧道渗涌水量的实测数据为基础 ,应用随机过程的理论和方法 ,建立了隧道渗涌水量的平稳序列预测模型 ,并将预测值与实测结果进行了对比 ,比较吻合。 相似文献
496.
On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used, the conversion regulations would have changed accordingly.Relationships of different substrates vary according to their locations. In the whole reactor, propionate‘s conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate‘s conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates‘ conversion. The ethanol-type fermentation of the acidogenicophase is the optimal acid-type fermentation for the two-phase anaerobic process. 相似文献
497.
Aerobic heterotrophic granular sludge was cultivated in a sequencing batch shaking reactor(SBSR) in which a synthetic wastewater containing glucose as carbon source was fed. The characteristics of the aerobic granules were investigated. Compared with the conventional activated sludge flocs, the aerobic granules exhibit excellent physical characteristics in terms of settleability, size, shape, biomass density, and physical strength.Scanning electron micrographs revealed that in mature granules little filamentous bacteria could be found, rod-shaded and coccoid bacteria were the dominant microorqanisms. 相似文献
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反应温度对自热式高温好氧消化(ATAD)中试系统运行的影响 总被引:4,自引:0,他引:4
城市污水污泥是城市污水处理厂的副产物,需要稳定化处理。本试验设计了由2个圆罐串联的自热式高温好氧消化中试系统处理城市污水污泥。通过批式试验探讨反应器温度对污泥稳定化处理效果的影响,以及影响反应器自升温的因素。试验发现①反应温度对挥发性的有机物的去除有显著影响,反应温度越高,VSS去除率越高。②影响反应温度的主要因素有进泥浓度、消化时间和曝气量。当进泥的VSS浓度为37.2g/L时,ATAD反应器最高温度可到49℃,只需14~17d的消化时间VSS的去除率可达到41.7%,污泥能达到稳定化。 相似文献