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对城市生活垃圾填埋处置技术的思考 总被引:7,自引:1,他引:7
本文分析了我国广泛使用的垃圾填埋技术——厌氧卫生填埋的缺点,介绍了当前新型的填埋技术——生物反应器填埋技术、好氧填埋技术、准好氧填埋技术、循环式准好氧填埋的原理、结构及各自的优缺点,据此指出我国今后垃圾填埋技术的研究方向。 相似文献
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兼氧膜生物反应器处理养殖废水技术 总被引:1,自引:0,他引:1
《中国环保产业》2014,(10):71-71
由江西金达莱环保股份有限公司开发的兼氧膜生物反应器处理养殖废水技术,适用于畜禽养殖废水、生活污水和各类工业有机废水处理。主要技术内容 一、基本原理 通过污泥培养,兼氧膜生物反应器(MBR)内部污泥质量浓度可达1.5万~2万mg/L,形成以高效兼性厌氧菌(约占80%)为优势菌种的特性微生物体系。 相似文献
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通过室内模拟试验,在渗滤液回灌的厌氧填埋柱基本进入稳定状态后,改用准好氧运行方式。同时监测了渗滤液中有机物浓度以压温度、pH值的变化。改变模拟垃圾柱的运行方式两个月以后。氨氯浓度由2000mg/L迅速下降至101.48mg/L,试验结果显示,准好氧运行方式可以解决生物反应器填埋场进入稳定阶段后存在的氨氮浓度高的问题,加速填埋场的稳定。 相似文献
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In this study, regression analysis based an estimation model for biogas generated from an up-flow anaerobic sludge blanket (UASB) reactor treating landfill leachate is developed using several leachate parameters, such as pH, conductivity, total dissolved solids, chemical oxygen demand, alkalinity, chloride, total Kjeldahl nitrogen, ammonia, total phosphorus. These landfill leachate parameters are monitorized over a period of 1000 days at 35 ± 1°C in the UASB reactor. In order to develop the best model giving highest estimation performance, eight model equations including different input parameter combinations are analyzed. Based on the results of regression analysis, the best coefficients of the model equation are determined. As a conclusion, the developed model in this study can give accurate biogas amount prediction for the USAB reactor-based leachate treatment system. 相似文献
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本文研究UASB反应器处理石灰法制浆的草浆蒸煮黑液,在较短时间内培养出首育良好沉淀性能和较高活性的厌氧颗粒污泥。并对其形态、结构和化学组份及不同生理类群的厌氧微生物特性等进行了观察和测试,结果表明厌氧颗粒污泥高活性的原因。为进一步探索厌氧颗粒污泥的形成机理提供了依据。 相似文献
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John R. Thene Heinz G. Stefan Ekaterini I. Daniil 《Journal of the American Water Resources Association》1989,25(6):1189-1198
ABSTRACT: A method to evaluate the effect of hydropower development on downstream dissolved oxygen (DO) is presented for a low head dam. Water, previously aerated during release over spillways and under gates, is diverted through the hydropower facility without further aeration. The oxygen transfer that occurs as a result of air entrainment at the various release points of a dam is measured. Oxygen transfer efficiencies are calculated and incorporated into an oxygen transfer model to predict average release DO concentrations. This model is used to systematically determine the effect of hydropower operation on downstream DO. Operational alternatives are investigated and a simple operational guide is developed to mitigate the effects of hydropower operation. Combinations of reduced generation and optimal releases from the dam allow the hydropower facility to operate within DO standards. 相似文献
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《International Journal of Greenhouse Gas Control》2007,1(2):158-169
Chemical-looping combustion (CLC) is a combustion technology where an oxygen carrier is used to transfer oxygen from the combustion air to the fuel, avoiding direct contact between air and fuel. Thus, CO2 and H2O are inherently separated from the rest of the flue gases and the carbon dioxide can be obtained in a pure form without the use of an energy intensive air separation unit. The paper presents results from a 3-year project devoted to developing the CLC technology for use with syngas from coal gasification. The project has focused on: (i) the development of oxygen carrier particles, (ii) establishing a reactor design and feasible operating conditions and (iii) construction and operation of a continuously working hot reactor. Approximately, 300 different oxygen carriers based on oxides of the metals Ni, Fe, Mn and Cu were investigated with respect to parameters, which are important in a CLC system, and from these investigations, several particles were found to possess suitable qualities as oxygen carriers. Several cold-model prototypes of CLC based on interconnected fluidized bed reactors were tested, and from these tests a hot prototype CLC reactor system was constructed and operated successfully using three carriers based on Ni, Fe and Mn developed within the project. The particles were used for 30–70 h with combustion, but were circulated under hot conditions for 60–150 h. 相似文献
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Carl Linderholm Alberto Abad Tobias Mattisson Anders Lyngfelt 《International Journal of Greenhouse Gas Control》2008,2(4):520
Chemical-looping combustion, CLC, is a technology with inherent separation of the greenhouse gas CO2. The technique uses an oxygen carrier made up of particulate metal oxide to transfer oxygen from combustion air to fuel. In this work, an oxygen carrier consisting of 60% NiO and 40% NiAl2O4 was used in a 10 kW CLC reactor system for 160 h of operation with fuel. The first 3 h of fuel operation excepted, the test series was accomplished with the same batch of oxygen carrier particles. The fuel used in the experiments was natural gas, and a fuel conversion to CO2 of approximately 99% was accomplished. Combustion conditions were very stable during the test period, except for the operation at sub-stoichiometric conditions. It was shown that the methane fraction in the fuel reactor exit gas was dependent upon the rate of solids circulation, with higher circulation leading to more unconverted methane. The carbon monoxide fraction was found to follow the thermodynamical equilibrium for all investigated fuel reactor temperatures, 660–950 °C. Thermal analysis of the fuel reactor at stable conditions enabled calculation of the particle circulation which was found to be approximately 4 kg/s, MW. The loss of fines, i.e. the amount of elutriated oxygen carrier particles with diameter <45 μm, decreased during the entire test period. After 160 h of operation the fractional loss of fines was 0.00022 h−1, corresponding to a particle life time of 4500 h. 相似文献
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Zhongyi Deng Rui Xiao Baosheng Jin Qilei Song 《International Journal of Greenhouse Gas Control》2009,3(4):368-375
Chemical-looping combustion (CLC) is a promising technology for the combustion of gas or solid fuel with efficient use of energy and inherent separation of CO2. The technique involves the use of an oxygen carrier which transfers oxygen from combustion air to the fuel, and hence a direct contact between air and fuel is avoided. A chemical-looping combustion system consists of a fuel reactor and an air reactor. A metal oxide is used as oxygen carrier that circulates between the two reactors. The air reactor is a high velocity fluidized bed where the oxygen carrier particles are transported together with the air stream to the top of the air reactor, where they are then transferred to the fuel reactor using a cyclone. The fuel reactor is a bubbling fluidized bed reactor where oxygen carrier particles react with hydrocarbon fuel and get reduced. The reduced oxygen carrier particles are transported back to the air reactor where they react with oxygen in the air and are oxidized back to metal oxide. The exhaust from the fuel reactor mainly consists of CO2 and water vapor. After condensation of the water in the exit gas from the fuel reactor, the remaining CO2 gas is compressed and cooled to yield liquid CO2, which can be disposed of in various ways.With the improvement of numerical methods and more advanced hardware technology, the time needed to run CFD (Computational fluid dynamics) codes is decreasing. Hence multiphase CFD-based models for dealing with complex gas-solid hydrodynamics and chemical reactions are becoming more accessible. Until now there were a few literatures about mathematical modeling of chemical-looping combustion using CFD approach. In this work, the reaction kinetics model of the fuel reactor (CaSO4 + H2) was developed by means of the commercial code FLUENT. The bubble formation and the relation between bubble formation and molar fraction of products in gas phase were well captured by CFD simulation. Computational results from the simulation also showed low fuel conversion rate. The conversion of H2 was about 34% partially due to fast, large bubbles rising through the reactor, low bed temperature and large particles diameter. 相似文献
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Colmenarejo MF Rubio A Sánchez E Vicente J García MG Borja R 《Journal of environmental management》2006,81(4):399-404
Eight small-scale municipal wastewater treatment plants were evaluated over a period of 19 months in the suburb of Las Rozas in Madrid (Spain). Four plants used compact extended aeration, two used conventional activated sludge, two used conventional extended aeration, one used a rotary biodisc reactor and the other used a peat bed reactor. The best results were obtained from the plants that used conventional technologies and the biodisc. Conventional activated sludge and extended aeration had higher removal efficiencies for ammonia, TSS, COD and BOD(5) and produced good quality final effluents for final disposal in accordance with the discharge standard. Empirical equations that correlated the concentration of dissolved oxygen in the effluents with the efficiencies of TSS, ammonia, COD and BOD(5) removals for all plants evaluated were obtained. The performance of the plants using compact extended aeration was affected more than those using conventional technologies or rotary biodisc when the capacity exceeded that of its initial design. 相似文献