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Kevbrina MV Nikolaev YA Danilovich DA Vanyushina AY 《Water science and technology》2011,63(10):2340-2345
Aerobic biological treatment of digested sludge was studied in a continuously operated laboratory set-up. An aerated reactor was filled with thermophilically digested sludge from the Moscow wastewater treatment plant and inoculated with special activated sludge. It was then operated at the chemostat mode at different flow rates. Processes of nitrification and denitrification, as well as dephosphatation, occurred simultaneously during biological aerobic treatment of thermophilically digested sludge. Under optimal conditions, organic matter degradation was 9.6%, the concentrations of ammonium nitrogen and phosphate decreased by 89 and 83%, respectively, while COD decreased by 12%. Dewaterability of digested sludge improved significantly. The processes were found to depend on hydraulic retention time, oxygen regime, and temperature. The optimal conditions were as follows: hydraulic retention time 3-4 days, temperature 30-35 degrees C, dissolved oxygen levels 0.2-0.5 mg/L at continuous aeration or 0.7-1 mg/L at intermittent aeration. Based on these findings, we propose a new combined technology of wastewater sludge treatment. The technology combines two stages: anaerobic digestion followed by aerobic biological treatment of digested sludge. The proposed technology makes it possible to degrade the sludge with conversion of approximately 45% volatile suspended solids to biogas, to improve nitrogen and phosphorus removal in reject water from sludge treatment units, and to achieve removal of malodorous substances after 8-9 days of anaerobic-aerobic sludge treatment. 相似文献
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Vanyushina AY Nikolaev YA Agarev AM Kevbrina MV Kozlov MN 《Water science and technology》2012,65(3):403-409
The process of anaerobic thermophilic digestion of municipal wastewater sludge with a recycled part of thickened digested sludge, was studied in semi-continuous laboratory digesters. This modified recycling process resulted in increased solids retention time (SRT) with the same hydraulic retention time (HRT) as compared with traditional digestion without recycling. Increased SRT without increasing of HRT resulted in the enhancement of volatile substance reduction by up to 68% in the reactor with the recycling process compared with 34% in a control conventional reactor. Biogas production was intensified from 0.3 L/g of influent volatile solids (VS) in the control reactor up to 0.35 L/g VS. In addition, the recycling process improved the dewatering properties of digested sludge. 相似文献
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以产品的需水量与产品成本之间的一般关系为基础,对需水量的弹性变化和估算方法进行了分析。在分析的基础上,建立了需水量计算的交互式算法模型和线性规划模型,提出了缺水地区城市工业需水量计算的一种方法,为解决大规模调水工程规划中计算受水区城市缺水量的难题,确定调水工程规模提供了一种参考方法。重点探讨水资源短缺地区工业与城市需水量的估算问题。 相似文献
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在长距离引水工程中,总干渠要穿过起伏的山峦,越过众多的河流,它是整个工程的主体项目。因此,选择最佳的纵横断面设计,要比常规设计方法显著减少工程量,这对缩短工程建设周期、节约投资县有重要意义。本文根据水力学原理,探讨了这一问题,并就南水北调中线方案的总干渠设计进行了阐述。 相似文献
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帕肖尔小流量量水槽流量公式的修正 总被引:1,自引:0,他引:1
帕肖尔小流量量水槽流量公式的修正主题词水流模型试验,流量测验,水动力学,水力计算简介率定原型宽度为0.305m的帕肖尔量水槽的一个1:3的缩尺模型,难以重现帕肖尔1926年得出的原型水槽的标准流量方程。这种偏差可能是由于按弗汝德准则建立的缩尺模型没有... 相似文献
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以产品的需水量与产品成本之间的一般关系为基础,对需水量的弹性变化和估算方法进行了分析,在分析的基础上,建立了需水量计算的交互工算法模型和线性规划模型,提出了缺水地区城市工业需水量计算的一种方法,为解决大规模调水工程规划中计算受水区城水缺水量的为难题。确定调水工程规模提供了一种参考方法。重点探讨水资源短缺地区工业与城市需水量的估算问题。 相似文献