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91.
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利用3个生物反应器研究了回流量的大小对模拟填埋场厌氧处理城市生活垃圾的影响。0号罐设定渗滤液不回流,1号罐和2号罐采取渗滤液回流措施,其回流量分别是10L/d(反应器体积的10.5%),20L/d(反应器体积的21%)。试验结果表明:1号罐中的甲烷产量和甲烷含量都要优于0号罐和2号罐。在2号罐中渗滤液回流量相对提高1倍后,其pH会下降而VFA和COD的浓度会有相应的增加。相对于10L的渗滤液回流量,高回流量(20L)有利于产甲烷化的启动和提高填埋气的产量和甲烷含量。但在反应后一阶段,高回流量(20L)导致产气量比低回流量的(10L)减少34.83%左右。 相似文献
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填埋垃圾腐殖质组成在填埋场稳定度表征中的应用 总被引:3,自引:0,他引:3
通过对上海老港生活垃圾填埋场1991-2004年封场单元填埋垃圾腐殖质组成的分析,考察了填埋垃圾中腐殖质组成随填埋龄的变化规律.研究结果表明,填埋垃圾腐殖质的总可提取率和胡敏酸(HA)与富里酸(FA)比值(HA/FA)分别随填埋龄呈线性下降和上升趋势.因此,填埋垃圾总可提取率和HA/FA可用来有效表征填埋场和填埋垃圾稳定度. 相似文献
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Organic matter and concentrated nitrogen removal by shortcut nitrification
and denitrification from mature municipal landfill leachate 总被引:5,自引:0,他引:5
An UASB+Anoxic/Oxic (A/O) system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^+-N loading rate (ALR) of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^+-N/(m^3-d) and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^+-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^+-N/(m^3.d), the NH4^+-N removal efficiency was more than 98%. With the influent NH4^+-N of 1200-1800 mg/L, the effluent NH4^+-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^+-N was only 2-3, the total inorganic nitrogen (TIN) removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria (AOB) accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria (NOB) accounted only for 0.2% of the total eubaeterial population. 相似文献
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Result-oriented approaches to the management of drinking water catchments in agricultural landscapes
Alexander Wezel Maria Zipfer Christine Aubry Fabienne Barataud Alois Heißenhuber 《Journal of Environmental Planning and Management》2016,59(2):183-202
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier. 相似文献