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中温两相UBF反应器处理养鸡场离心废水的试验分析 总被引:7,自引:0,他引:7
在中温 35℃采用两相 UBF反应器处理养鸡场离心废水 ,结果表明 :进水 CODcr为 190 0 0 mg/ L,系统容积负荷 2 1.5 4kg CODcr/ m3· d,水力停留时间 2 1.17hr,CODcr去除率为 81.98% ,BOD5 去除率为 90 .45 % ,产气率为 0 .44 6 m3/kg CODcr 相似文献
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Müller K Pelzing M Gnauk T Kappe A Teichmann U Spindler G Haferkorn S Jahn Y Herrmann H 《Chemosphere》2002,49(10):1247-1256
An increasing percentage of agricultural land in Germany is used for oil seed plants. Hence, rape has become an important agricultural plant (in Saxony 1998: 12% of the farmland) in the recent years. During flowering of rape along with intensive radiation and high temperatures, a higher production and emission of biogenic VOC was observed. The emissions of terpenes were determined and more importantly, high concentrations of organic carbonyl compounds were observed during this field experiment. All measurements of interest have been carried out during two selected days with optimal weather conditions. It is found that the origin or the mechanism of formation of different group of compounds had strong influence on the day to day variation of their concentrations. The emission flux of terpenes from flowering rape plants was determined to be 16–32 μg h−1 m−2 (30–60 ng h−1 per g dry plant––540–1080 ng h−1 per plant), in total. Limonene, -thujene and sabinene were the most important compounds (about 60% of total terpenes). For limonene and sabinene reference emission rates (MS) and temperature coefficients were determined: βlimonene=0.108 K−1 and MS=14.57 μg h−1 m−2; βsabinene=0.095 K−1 and MS=5.39 μg h−1 m−2.
The detected carbonyl compound concentrations were unexpectedly high (maximum formaldehyde concentration was 18.1 ppbv and 3.4 ppbv for butyraldehyde) for an open field. Possible reasons for these concentrations are the combination of primary emission from the plants induced by high temperature and high ozone stress, the secondary formation from biogenically and advected anthropogenically emitted VOC at high radiation intensities and furthered by the low wind speeds at this time. 相似文献
127.
污泥与高浓度有机废物厌氧消化反应中的产气量 总被引:3,自引:0,他引:3
研究了高温/中温两相厌氧消化反应器系用以同时处理污泥与不同高浓度有机废物时产气及产甲烷的变化特性。结果表明,气体及甲烷主要是在第二段的中温消化反应器内产生。当中温消化反应器的有机负荷VS为1.65 ̄3.10kg/m^3d时,稳态条件下的平均产气量为1.958 ̄4.020m^3/d,气体中甲烷的平均组成为65% ̄73%,甲烷的比产率为0.397 ̄0.511m^3/kgVS。 相似文献
128.
Dale R. Van Stempvoort James Armstrong Bernhard Mayer 《Journal of contaminant hydrology》2007,92(3-4):184-207
Despite a rapid expansion over the past decade in the reliance on intrinsic bioremediation to remediate petroleum hydrocarbon plumes in groundwater, significant research gaps remain. Although it has been demonstrated that bacterial sulfate reduction can be a key electron accepting process in many petroleum plumes, little is known about the rate of this reduction process in plumes derived from crude oil and gas condensates at cold-climate sites (mean temperature <10 degrees C), and in complex hydrogeological settings such as silt/clay aquitards. In this field study, sulfate was injected into groundwater contaminated by gas condensate plumes at two petroleum sites in Alberta, Canada to enhance in-situ bioremediation. In both cases the groundwater near the water table had low temperature (6-9 degrees C). Monitoring data had provided strong evidence that bacterial sulfate reduction was a key terminal electron accepting process (TEAP) in the natural attenuation of dissolved hydrocarbons at these sites. At each site, water with approximately 2000 mg/L sulfate and a bromide tracer was injected into a low-sulfate zone within a condensate-contaminant plume. Monitoring data collected over several months yielded conservative estimates for sulfate reduction rates based on zero-order kinetics (4-6 mg/L per day) or first-order kinetics (0.003 and 0.01 day(-1)). These results favor the applicability of in-situ bioremediation techniques in this region, under natural conditions or with enhancement via sulfate injection. 相似文献
129.
Konrad Müller Matthias Pelzing Thomas Gnauk Anett Kappe Ulrich Teichmann Gerald Spindler Sylvia Haferkorn Yvonne Jahn Hartmut Herrmann 《Chemosphere》2002,49(10)
An increasing percentage of agricultural land in Germany is used for oil seed plants. Hence, rape has become an important agricultural plant (in Saxony 1998: 12% of the farmland) in the recent years. During flowering of rape along with intensive radiation and high temperatures, a higher production and emission of biogenic VOC was observed. The emissions of terpenes were determined and more importantly, high concentrations of organic carbonyl compounds were observed during this field experiment. All measurements of interest have been carried out during two selected days with optimal weather conditions. It is found that the origin or the mechanism of formation of different group of compounds had strong influence on the day to day variation of their concentrations. The emission flux of terpenes from flowering rape plants was determined to be 16–32 μg h−1 m−2 (30–60 ng h−1 per g dry plant––540–1080 ng h−1 per plant), in total. Limonene, α-thujene and sabinene were the most important compounds (about 60% of total terpenes). For limonene and sabinene reference emission rates (MS) and temperature coefficients were determined: βlimonene=0.108 K−1 and MS=14.57 μg h−1 m−2; βsabinene=0.095 K−1 and MS=5.39 μg h−1 m−2.The detected carbonyl compound concentrations were unexpectedly high (maximum formaldehyde concentration was 18.1 ppbv and 3.4 ppbv for butyraldehyde) for an open field. Possible reasons for these concentrations are the combination of primary emission from the plants induced by high temperature and high ozone stress, the secondary formation from biogenically and advected anthropogenically emitted VOC at high radiation intensities and furthered by the low wind speeds at this time. 相似文献
130.
矿山开采过程产生的酸性排水及其携带的重金属对生态环境造成了严重的危害,其防控的关键在于控酸,因此矿井水酸化过程的解析可为矿山酸性排水的源头防控提供理论依据。本文以独山半坡锑矿为研究区,采集矿井内部不同区域水体样品32件,通过对水体酸化的矿物端元解析和重金属的共氧化过程、离子水解过程以及不同类型矿井水的混合过程分析,揭示了矿井水的酸化过程。结果表明,矿井内辉锑矿与黄铁矿的氧化使流经的矿井水具有低p H和高硫酸根的特征,与未受矿业活动影响的地下水具有明显差异。在矿井水流动过程中,Sb(Ⅲ)与Fe(Ⅱ)的共氧化过程消耗了氢离子,不同水体混合过程中碳酸氢根对酸的缓冲作用明显,以上过程延缓了矿井水的酸化;由于水体酸化使Al、Mn、Fe等离子溶出,而这些离子可能发生的水解过程加速了矿井水的酸化。 相似文献