沼气变压吸附脱碳影响因素分析及吸附剂比选

生物天然气(bio-natural gas)是由生物质转化而来,目前主要指通过沼气净化提纯得到的生物甲烷气(bio-methane)。由于生物天然气可以直接作为石化天然气的替代燃料,所以发展沼气已成为增加天然气供应量的一个重要方向。沼气提纯制取生物天然气不仅对我国新能源革命有重要意义,也是减少我国对国外能源依赖的重要一环,沼气中的CO_2不仅会降低沼气热值,还会造成温室效应。因此,沼气提纯的关键在于CO_2的脱除。该文介绍了变压吸附技术脱除沼气中的CO_2的原理,并总结了吸附时间、吸附压力、气体流量以及多床层工艺对变压吸附分离CO_2/CH_4的影响,介绍并比对了不同种类吸附剂的特点与性能。     

生物天然气产业七问

<正>天然气是绿色、低碳的清洁能源,而生物天然气被寄望在改进城镇能源结构、消除城市雾霾、甚至维护能源安全上"大展拳脚",但它的产业化道路却并不顺畅。生物天然气如何找到适合发展的商业模式,在产业推进中不断解决技术问题?据了解,英国、德国、瑞典等欧盟国家,早已形成较完善的沼气产业,并积极开发生物天然气。本刊编辑特将近期生物天然气专家、全国人大代表雍瑞生和生物天然气专家、北京石油管理干部学院教授彭庆的最新观点和看法摘编,以供行业参考。     

绿色环保 节能可靠——雅迪勤变频沼气螺杆压缩机

正1月7日消息,东莞雅迪勤压缩机制造有限公司研发生产的2套776Nm3/h-15.5bar变频沼气螺杆压缩机配套项目于近日成功调试,并成功交付给客户使用,变频沼气螺杆压缩机首次应用于生物发酵沼气提纯天然气案例,同时该产品于2016年12月13日获得2016年度香港工商业奖-设备及机器设计优异证书。随着世界经济的高速发展,世界能源危机的不断涌现,石油、天然气等能源供应日趋     

上海在“十二五”规划期间积极发展热电联产与分布式供能系统

分布式功能系统是指在用户端或靠近用户现场独立输出电热(冷)能的系统,该系统既能发电,又能利用余热制冷、供暖、供应热水,使用的能源包括天然气、沼气及可再生能源等清洁能源。近年来,分布式功能系统迅速发展,不少发达国家积极推动,主要用于工业园区、公共设施和住宅等领域。我国积极鼓励这种供能方式,上海自2004年起开始推动发展,主要针对以天然气、沼气等为燃料的小型供能系统(单机1万千瓦以下),出台了支持     

天然气计量技术发展趋势分析

介绍了国内外天然气计量状况和我国天然气计量技术发展现状,分析了我国天然气计量技术发展趋势及展望.     

低压天然气的回收再利用及节能环保措施

天然气作为一种宝贵的清洁能源,在能源结构中有着重要的地位。该文分析了低压天然气回收的必要性,探究低压天然气的回收,做好有效的节能环保。     

天然气加工工业的发展概况

略述了国内外天然气的开发情况及天然气加工工业的发展概况,分析了天然气液化及分离技术中的几个关键性问题,并对我国天然气工业的发展在方针和具体措施方面提出了几点看法。     

天然气流量计量技术发展趋势

天然气流量计量是天然气生产、输送和销售的关键环节,本文分析了发展天然气计量技术的意义,结合我国天然气工业发展的需要对天然气计量技术的发展趋势进行了预测。     

天然气能量计量应用的探讨

近年来,我国已经在能量计量技术开发方面取得了长足的进步,我国天然气计量方式与国际惯例接轨是大势所趋,实行天然气按能量计量和计价在我国已迫在眉睫。我国实施天然气按能量计价,技术上已没有任何障碍,标准体系已基本具备,天然气生产、运输、销售企业也基本具备器具设备条件,天然气用户企业无需进行技术和设施改造。已持续开展多项前期研究与模拟试验,企业与用户普遍赞同实施能量计价。因此,更多的是需要质检部门进一步完善相关的实施技术标准和规程,建立更高水平的天然气量值溯源体系,建立天然气质量监督体系,政府出台合理的天然气能量价格政策,支持和引导天然气实施能量计量。     

沼气供应技术研究现状

中国城乡巨大的有机废物废水蕴藏着可观的资源,废物消化得到的一系列产物即沼气、沼渣和沼液均有可能产生巨大的经济效益。沼气作为可再生的绿色燃料,目前已在供热、热电联产、车用燃料、并入天然气管道等方面展现出良好的应用前景。了解国内外沼气供应技术的发展水平,总结先进技术经验,同时结合我国实际情况,着重介绍沼气并网发展模式,研究沼气掺混工艺、设备及相关技术规定,使沼气成为天然气消费缺口的补充,可以此推进城乡统筹和低碳循环经济。     

Underdog or bulldog: introducing biogas technologies in Estonia

The production and use of biogas, along with corresponding sector-specific activities and technologies, is a relatively new subject in Estonia. This paper gives an instructive overview of main barriers behind the development incentives, policy support and technological innovation in terms of emerging market for biogas. The article examines the complexity of market-related, political, technological and social obstacles for introduction biogas technologies. There is a major gap between resource potential, technological capacity and practice in Estonia. About 2?% of the theoretical potential of biogas is being used, totalling around 11?million?Nm³, based primarily on landfill biogas. First, political setting for biogas innovation is still vague, however, consolidated and enhanced since 2010 to compete with other renewables and mainstream energy technologies. The article underlines the statement that the reason why Estonian biogas production has not followed the path of growth and technology transfer is the low renewable electricity feed-in tariff. However, there are many other legal and engineering factors that have held back biogas applications and sector development in general. Stakeholders have established the Estonian Biogas Association, increasing sector’s visibility, targeted lobby to support policy-making, technological and social innovation and professional networking. Though getting the biogas sector to succeed demands a comprehensive approach and involvement of more actors in demand side including local leaders and consumers, both enthusiasm and scepticism should be informed by a sound understanding of framework conditions and complexities for path-breaking transformations in energy systems. To promote biogas production, profitable and technologically feasible showcases should demonstrate benefits and issues to the target group and stakeholders. Instead agricultural and CHP development mode, the priority of using biogas in Estonia could be seen as green vehicle fuel for transport.     

A Technological Overview of Biogas Production from Biowaste

The current irrational use of fossil fuels and the impact of greenhouse gases on the environment are driving research into renewable energy production from organic resources and waste. The global energy demand is high, and most of this energy is produced from fossil resources. Recent studies report that anaerobic digestion (AD) is an efficient alternative technology that combines biofuel production with sustainable waste management, and various technological trends exist in the biogas industry that enhance the production and quality of biogas. Further investments in AD are expected to meet with increasing success due to the low cost of available feedstocks and the wide range of uses for biogas (i.e., for heating, electricity, and fuel). Biogas production is growing in the European energy market and offers an economical alternative for bioenergy production. The objective of this work is to provide an overview of biogas production from lignocellulosic waste, thus providing information toward crucial issues in the biogas economy.     

Applicability of selected methods and sorbents to simultaneous removal of siloxanes and other impurities from biogas

This paper critically reviews and discusses the state-of-the-art technologies for the removal of siloxanes from biogas, which could be used to simultaneously remove other contaminants. The reasons for purifying biogas, the scope of this purification and the recommended (depending on the biogas utilization equipment) concentrations of volatile silicon-organic compounds are presented. Established and new promising methods of removing typical methylsiloxanes from biogases from municipal landfills and sewage sludge are characterized and analyzed. Their suitability for the simultaneous removal of other trace biogas impurities and possibilities of regenerating the spent sorbent are assessed. It is shown that the commonly used activated carbon is not suitable for comprehensive biogas treatment. On the basis of the analysis, an adsorption method using halloysite (a natural zeolite mineral) as an inexpensive, universal and regenerable adsorbent is proposed. The method can be used after physicochemical treatment to comprehensively purify biogas from methylsiloxanes, hydrogen sulfide, ammonia, halides and other technically and environmentally burdensome impurities. Some directions for further research in this regard and possible environmentally safe ways of utilizing the spent sorbent are indicated.     

Anaerobic fermentation by aquatic product wastes and other auxiliary materials

The efficiency of the biogas production from aquatic product wastes was researched through the proportioning materials of nine part organic waste to one part rice straws, peanut hull powder or food wastes, respectively. Such four treatments were analyzed to see their respective impacts on gas production of anaerobic fermentation. And then the biogas slurry of each treatment was used for inhibiting experiment on Fusarium oxysporum f.sp.niveum (FON). The final result indicated that organic wastes mixed with food wastes guaranteed quality and quantity of biogas production. The unsterilized biogas slurry displayed strong inhibiting effect on FON growth by 78.17 %. The daily largest biogas production was 3,870 mL/day on the 25th day, the total biogas production 38,230 mL and TS biogas production rate 692.42 mL/g, respectively, in Group D from fish waste and food waste.     

Biogas production from energy crops in northern Greece: economics of electricity generation associated with heat recovery in a greenhouse

Herein a techno-economic assessment was performed on an energy-crop-based biogas plant coupled with a greenhouse for utilizing thermal energy produced by cogeneration. Seven energy crops were evaluated: triticale, maize, alfalfa, sunflower, clover, barley and wheat. According to the evaluation, triticale was the most competitive energy crop under selected climate conditions for northern Greece. Although maize displays higher biomass yield and biogas potential than the drought-resistant crop triticale, it has high irrigation demand that contributes significantly to total production costs. For a triticale-based biogas production to become economically feasible, agricultural arable area larger than 500 ha, or biogas plant size larger than 1000 kW_el, is required. However, with public funding, biogas production becomes feasible at smaller area (>250 ha) or biogas plant size (>500 kW_el). The inclusion of a greenhouse into the design of the biogas plant contributes positively to the economic viability of the entire system. Under this scenario, greenhouse financial income accounts for about 17–18% of total income. Results of a sensitivity analysis suggest that the selection of an appropriate energy crop for biogas production should be based principally on both digestibility (specific methane yield) and biomass yield per hectare, these factors being more critical than biomass production costs.     

Experimental study on performance of a biogas engine driven air source heat pump system powered by renewable landfill gas

The equipment configuration of a landfill gas (LFG) fueled biogas engine driven air source heat pump system was studied. The process flow for collecting and purifying LFG was analyzed, and the LFG collection and purification method was determined. An experimental apparatus was set up, and the effect of biogas engine speed variation on LFG consumption, exhaust fume temperature of biogas engine, recovered waste heat from exhaust fume and cylinder liner, coefficient of performance (COP) of the heat pump and primary energy ratio (PER) of the system were experimentally tested. The results indicated that LFG consumption and biogas engine exhaust fume temperature increased with biogas engine speed. When the biogas engine operated in the 70%–90% rated speed range, the system heat output and exhaust fume waste heat recovery rate would be relatively higher. In addition, the maximum COP and PER reached 4.2 and 1.4 respectively.     

Studies in biogas technology. Part IV. A novel biogas plant incorporating a solar water-heater and solar still

A reduction in the heat losses from the top of the gas holder of a biogas plant has been achieved by the simple device of a transparent cover. The heat losses thus prevented have been deployed to heat a water pond formed on the roof of the gas holder. This solar-heated water is mixed with the organic input for ‘ hot-charging ’ of the biogas plant. A thermal analysis of such a solar water-heater ‘ piggy-backing ’ on the gas holder of a biogas plant has been carried out. To test whether the advantages indicated by the thermal analysis can be realised in practice, a biogas plant of the ASTRA design was modified to incorporate a roof-top solar water-heater. The operation of such a modified plant, even under ‘ worst case ’ onditions, shows a significant improvement in the gas yield compared to the unmodified plant. Hence, the innovation reported here may lead to drastic reductions in the sizes and therefore costs of biogas plants. By making the transparent cover assume a tent-shape, the roof-top solar heater can serve the additional function of a solar still to yield distilled water. The biogas plant-cum-solar water-heater-cum-solar still described here is an example of a spatially integrated hybrid device which is extremely cost-effective.     

大型养殖场沼气工程

结合国内外大中型沼气工程情况,以德青源沼气工程为例,介绍了农村废弃物变废为宝的工艺流程,提供了农村能源解决方案,并结合我国沼气工程现有问题提出几点建议,以使大中型沼气工程走向规范化。     

大型养殖场沼气工程——以北京德青源沼气工程为例

结合国内外大中型沼气工程情况,以德青源沼气工程为例,介绍了农村废弃物变废为宝的工艺流程,提供了农村能源解决方案,并结合我国沼气工程现有问题提出几点建议,以使大中型沼气工程走向规范化.