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81.
针对猪场沼液氮磷浓度高、有机物含量大且可生化性差等特点,采用A/O—序批式生物膜反应器—氧化塘—人工湿地组合工艺对沼液进行深度处理。处理规模400 m~3/d,工程总投资117.5万,运行费用1.46元/(m~3·d)。运行结果表明,经过该组合工艺处理后COD_(Cr)、BOD_5、SS、NH_3-N、TP去除率分别为85.93%、79.84%、89.86%、94.78%、88.67%,出水指标均符合《畜禽养殖业污染物排放标准》(GB 18596—2001)要求。  相似文献   
82.
Silage effluent is generally regarded as one of the major agricultural pollutants of water courses. Efficient anaerobic digestion of silage effluent was achieved by a 3-day hydraulic retention in an upflow anaerobic filter. The filter was a laboratory scale unit containing a limestone chip support matrix. At loading rates ranging from 7.8 to 14.2 kg COD m−3 active volume day−1, the average COD removal obtained ranged from 86 to 89% with a TOA removal of 82–88%. The methane content of the biogas produced ranged from 81 to 88%. The rate of COD conversion to CH4 was independent of the loading rate under the conditions tested and the observed efficiency averaged 0.357 m1 CH4(STP) kg−1 COD introduced to the reactor.The reactor tolerated considerable variation in influent pH without any apparent decrease in digestion efficiency. It is apparent from the results obtained that a reactor which is in routine use for slurry digestion may also be utilised for silage effluent digestion on a seasonal basis.  相似文献   
83.
对高盐分餐厨垃圾湿式厌氧发酵进行了研究,试验结果表明:发酵液盐分浓度不断累积,由最初的0.084%增长至0.69%,并且还在继续增加;进料有机负荷控制在3 kgVS/(m3·d)时,反应器运行良好,发酵液COD稳定在2 620 mg/L左右,VFA浓度保持在880 mg/L以下,产气量81 L/d,甲烷含量60%左右.  相似文献   
84.
Energy protection of buildings can be achieved by using suitable construction with minimisation of thermal bridges. This paper is a contribution to the characterisation of the thermal defects and energy efficiency of the envelope on the case study of a solid-state biogas plant. The work specifically concerns the qualitative evaluation of envelope construction details by infrared thermography technique and quantitative evaluation of thermal defects by calculation. Results show that wall constructions of the solid-state biogas plant have an unsuitable engineering solution causing high heat losses. The main problem is the existence of significant numbers of thermal bridges caused by uninsulated bearing steel frames of the façade system, gates, doors and windows.  相似文献   
85.
Mixed‐matrix membranes comprising NH2‐MIL‐53(Al) and Matrimid or 6FDA‐DAM have been investigated. The metal organic framework (MOF) loading has been varied between 5 and 20 wt%, while NH2‐MIL‐53(Al) with three different morphologies, nanoparticles, nanorods, and microneedles has been dispersed in Matrimid. The synthesized membranes have been tested in the separation of CO2 from CH4 in an equimolar mixture. At 3 bar and 298 K for 8 wt% MOF loading, incorporation of NH2‐MIL‐53(Al) nanoparticles leads to the largest improvement compared to nanorods and microneedles. The incorporation of the best performing filler, i.e., NH2‐MIL‐53(Al) nanoparticles, into the highly permeable 6FDA‐DAM has a larger effect, and the CO2 permeability increases up to 85% with slightly lower selectivities for 20 wt% MOF loading. Specifically, these membranes have a permeability of 660 Barrer with a CO2/CH4 separation factor of 28, leading to a performance very close to the Robeson limit of 2008. Furthermore, a new non‐destructive technique based on Raman spectroscopy mapping is introduced to assess the homogeneity of the filler dispersion in the polymer matrix. The MOF contribution can be calculated by modeling the spectra. The determined homogeneity of the MOF filler distribution in the polymer is confirmed by focused ion beam scanning electron microscopy analysis.  相似文献   
86.
农村综合能源系统通过多种能源的协同互补,在满足农村用户多元化用能需求的同时,能有效提升能源利用效率和用能经济性.首先,在考虑适应农村典型场景的基础上,提出了一种三层协同自律的农村综合能源分层协同运行优化框架.然后,基于农村综合能源系统典型设备,建立了三层农村综合能源系统源储荷联合优化调度模型以及相应的优化调度流程.调度...  相似文献   
87.
通过参加伊朗造纸项目废水车间IC塔沼气燃烧系统开车调试总结,介绍了IC塔沼气燃烧系统主要设备及投料试车、控制联锁及调试期间注意事项等。  相似文献   
88.
Biogas plants enable power to be generated in a flexible way so that variable, renewable energy sources can be integrated into the energy system. In Germany, the Renewable Energy Sources Act promotes flexible power generation in biogas plants. Two existing biogas plants in flexible operation were analyzed with respect to economic viability and greenhouse gas (GHG) emissions to assess the feasibility of flexible operation. To do this, a biogas technology simulation model was developed to reproduce the technical design of both biogas plants and to link this design with twelve flexibilization scenarios. The evaluation of the economic viability is based on a discounting method of investment appraisal. For assessing the level of GHG emissions, the life cycle assessment method has been applied. The results show that the profitability of flexibilization is contingent upon premium payments promoting flexibility and direct sales resulting from a higher electrical efficiency of new or additionally installed combined heat and power units. Overall, with respect to profitability, the results of the flexible power generation scenarios are dependent upon the properties of the technical plant, such as its power generation and gas storage capacities. Relative GHG emissions from flexible biogas plants show significantly lower values than for referenced fossil gas–steam power stations. Among the various scenarios, the results reveal that the level of GHG emissions especially depends on the number of operating hours of the additional combined heat and power unit(s). The results of the analyzed biogas plants showed no direct correlation between GHG emissions and the economic benefits. Overall, a flexible power generation of biogas plants may improve the economic viability as well as result in lower GHG emissions in comparison with a conventional base load operation. © 2016 The Authors. International Journal of Energy Research published by John Wiley & Sons Ltd.  相似文献   
89.
During biogas combustion, siloxanes form deposits of SiO2 on engine components, thus shortening the lifespan of the installation. Therefore, the development of new methods for the purification of biogas is receiving increasing attention. One of the most effective methods is physical absorption with the use of appropriate solvents. According to the principles of green engineering, solvents should be biodegradable, non-toxic, and have a high absorption capacity. Deep eutectic solvents (DES) possess such characteristics. In the literature, due to the very large number of DES combinations, conductor-like screening models for real solvents (COSMO-RS), based on the comparison of siloxane activity coefficient of 90 DESs of various types, were studied. DESs, which have the highest affinity to siloxanes, were synthesized. The most important physicochemical properties of DESs were carefully studied. In order to explain of the mechanism of DES formation, and the interaction between DES and siloxanes, the theoretical studies based on σ-profiles, and experimental studies including the 1H NMR, 13C NMR, and FT-IR spectra, were applied. The obtained results indicated that the new DESs, which were composed of carvone and carboxylic acids, were characterized by the highest affinity to siloxanes. It was shown that the hydrogen bonds between the active ketone group (=O) and the carboxyl group (-COOH) determined the formation of stable DESs with a melting point much lower than those of the individual components. On the other hand, non-bonded interactions mainly determined the effective capture of siloxanes with DES.  相似文献   
90.
选择碳分子筛,以CH4和CO2为原料气,对变压吸附法提纯沼气中生物甲烷的分离性能进行了研究。采用高精度智能重量分析仪IGA-100测定了25℃下CH4、CO2和N2纯组分气体在碳分子筛上的吸附平衡等温线,计算了3种气体在碳分子筛内的扩散速率CO2>N2>CH4。使用单塔变压吸附装置测量了动态吸附穿透曲线,考察了吸附压力、气体流量和少量氮气等因素对吸附分离的影响,并对吸附机理做了初步探讨。实验结果表明,在吸附压力为0.4MPa、气体流量为200mL/min时,在碳分子筛上CO2穿透吸附量为35.9mL/g,CH4穿透吸附量为5.4mL/g,CO2/CH4分离系数高达12.6,可直接从吸附塔顶富集纯净的CH4,而且碳分子筛可以通过抽真空完全再生,是一种理想的吸附材料;在有少量氮气存在的实验条件下,由于碳分子筛对CH4和N2具有动力学分离效应,仍能在塔顶富集高浓度的CH4。  相似文献   
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