3MW集中式热电肥联产沼气工程设计与建设

山东民和牧业股份有限公司利用所属23家养殖场的鸡粪和污水作为沼气发酵原料,投资建设大型畜禽养殖场集中式沼气发电工程.原料经水解除砂工艺将鸡粪中的砂砾除去,保证发酵效率;采用中温(38 ℃)发酵工艺,产沼气30 000 m3/d;采用高效率低运行成本的生物脱硫工艺,将沼气中的H2S含量降至200×10-6以下;经净化的沼气在双膜干式贮气柜中贮存,供给热电联产的发电机组使用.发电量60 000 kWh/d,机组余热用于冬季发酵系统自身增温;发酵后的沼液用作周围葡萄、苹果及玉米地的有机肥料.项目实现了温室气体减排84882tCO2当量.文章介绍了该沼气发电工程的工艺特点和技术要点,为同类型沼气发电工程设计和建设提供参考.     

大型沼气工程运行分析

以北京德青源沼气工程和山东民和沼气工程为实例介绍采用CSTR工艺对鸡粪进行厌氧发酵,其pH为6.88～8.49、氨氮为5 000 mg/L、VFA 80 mmol/l,运行稳定良好;采用新型生物脱硫技术对沼气进行脱硫净化,H2S去除率能够达到97%以上,为大型沼气工程的调试与运行提供参考.     

猪粪污水沼气发电工程的效益分析

猪粪长期以来作简单的有机肥使用,不仅污染环境,而且还存在着大量生物质能源浪费、肥效流失严重等问题。萧山市龙翔公司年产1.2万头供港猪养殖场,由于整个生产线采用集约化饲养和高架漏网结构,大量粪水集中,加之用水冲栏,污水量大,给周围环境造成严重的污染,仅1991年由于污染造成大量鱼死亡,直接经济损失达5万余元。为了从根本上解决猪粪污水污染问题,于1993年建造了500m~3猪粪污水沼气发电工程,发电能力75kW。经过三年来的运行使用,该工程各项技术指标均达到设计要求,获得了较好的经济、社会、环境、能源综合效益,为禽畜养殖场污水处理提供了示范。     

污水厂热电联产工程效益分析

青岛某污水厂每天进水量约为14.5万t,该厂污水处理采用"中温厌氧消化+热电联产"工艺。文中通过对该厂设备正常运行数据,其中包括日处理污水量、污泥量、沼气产量、效益及发电量等进行了系统整理与分析,由于该污水厂采用厌氧消化技术,并通过回收发电机烟气余热和缸套水余热来加热消化池,该技术的应用不仅节约了该厂能源消耗,而且还提高了产气的稳定性。由于该厂沼气发电量为厂内自用,因此,该厂还节省了约22%的购电费用。     

沼气发电大有可为

沼气是一种资源丰富而又价廉的新能源。利用沼气发电可以缓解商品电的不足,具有良好的应用前景。山东省莱芜市中榆林村10千瓦沼气发电机组,自1984年8月运行以来,基本上满足了全村120户农民的全部生活用电和部分生产用电的需要,每年可节约电费4500元,8年累计节约燃油1.5万公斤,价值1.2万元。一、沼气发电机组的选用与改装目前沼气发电采用的机型大体有两种:一种是单燃料全烧沼气机型,这种机型一般功率较小,只有     

大型工业沼气停止产气处理技术

笔者参与了某大型工业沼气停止产气的现场分析诊断，查明其原因系发酵受阻，菌种毒衰邙；采用快速 富集培育高温新菌种的技术处理方案，４０天后启动正常恢复供气。     

餐厨垃圾沼气热电联产经济分析

餐厨垃圾是典型的高有机质、高水分及高盐分废弃物,危害性和资源可利用性并存。若不能正确处理,极易腐烂变质甚至传播细菌和病毒。青岛某公司为实现餐厨垃圾无害化处理,采用高温湿式单相连续厌氧发酵热电联产技术,探索将餐厨垃圾转化为生物柴油、燃料酒精、沼气、有机肥、土壤改良剂和饲料添加剂等物质的有效方法,同时实现了废弃物的减量化、无害化以及能源化。文中结合该公司实际现状,探讨厌氧发酵技术在餐厨垃圾处理方面的潜力和优势,为餐厨垃圾的无害减量化处理找到更好的发展方向。     

我国最大鸡粪沼气发电厂正式发电

GE能源集团近日宣布其在中国最大的鸡粪发电厂——山东民和股份沼气发电清洁机制项目开始正式运营。项目利用3台GE颜巴赫JMS3201兆瓦燃气内燃机发电,总装机容量3兆瓦。利用厌氧发酵系统对鸡粪进行发酵,日可消耗300吨鸡粪及500吨废水。产生的沼气被输送到颜巴赫燃气内燃机中,发出的电力被输入当地电网,发酵剩余的沼渣还可制成肥料。     

Intensification of biogas production using various technologies: A review

Anaerobic digestion (AD) is an organic matter conversion technology which offers a wide range of options for production of biogas from organic biomass, providing an excellent opportunity to convert abundant bioresources into safe, eco-friendly, renewable energy. Important factors in the process of AD are the biodiversity of microorganisms, chemical load of oxygen demand, and content of water and total solids. A challenge for the future is to find technologies that will maximally enhance biogas production and to find pathways for biogas to supersede well-established technologies and practices in the contemporary heavily fossil fuel-based energy system. Current studies on technologies of biogas production indicate a number of possibilities of using appropriate biological and physicochemical additives, like added enzymes or fruit pomace, as well as immobilizing microorganisms on biofilters. Anaerobic biorefinery is an emerging concept that generates not only bioenergy but also high-value biochemical products from the same feedstock. This study is a review of articles describing the intensification of biogas production by using various technologies.     

鸡粪厌氧消化过程中水解酶与沼气产量的关系研究

研究了鸡粪在厌氧消化全过程中几种水解酶活的变化与沼气产量的关系。结果表明,纤维素酶、脂肪酶、液化型淀粉酶和糖化型淀粉酶 的酶活在发酵过程中是变化的,与产气量是相关的;酶活最大值出现在产气高峰期的附近;酸、中、碱蛋白酶活性在消化过程中不断降低。     

Assessment of combined heat and power (CHP) integrated with wood-based ethanol production

A techno-economic assessment is made of wood-based production of ethanol, where the by-products are used for internal energy needs as well as for generation of electricity, district heat and pelletised fuel in different proportions for external use. Resulting ethanol production costs do not differ much between the options but a process where electricity generation is maximised by use of the solid residues as fuel for a combined cycle is found to give 20% more reduction of green-house gas emissions per liter of ethanol produced than the other options. Maximising electricity generation at the expense of district heat generation also allows more freedom when suitable sites for ethanol plants are looked for. Use of gasified biofuel for a combined cycle power plant is a demonstrated technology, however, the low ash and alkali content of the hydrolysis residue may allow direct combustion in the gas turbine topping cycle. This would reduce the necessary investment considerably. The potential advantages of using a combined cycle for maximising the electric power output from an energy combinate, producing ethanol and electricity from biomass, justifies further exploration of the possibilities for using hydrolysis residue directly as gas turbine fuel.     

垃圾焚烧热电联产蒸汽参数选择

针对垃圾焚烧热电联产时,采用中温中压及中温次高压蒸汽参数对全厂投资及经济性的影响进行研究。以日处理规模为600 t·d^-1的生活垃圾焚烧设施作为研究对象,从主机设备参数、主机设备投资额、经济指标、营业收入及投资回收期等5个方面进行分析。研究结果表明,采用中温次高压参数时,垃圾焚烧设施热电联产全厂热效率较采用中温中压参数时提高1.7%,热电联产时全年总收入较采用中温中压参数时提高11.5%,且经济性更好,静态投资回收期约为4.73年。     

高温状态下鸡粪厌氧发酵产酸影响因素的研究

叙述了以鸡粪为发酵底物,在高温(60℃)状态下采用单因子批式实验,发酵产物液相挥发性脂肪酸(VFAs)的含量与分布情况以及发酵时间、原料含固率(TS)、初始pH值对于鸡粪厌氧发酵产酸效果的影响,指出,发酵时间、TS和初始pH值对鸡粪发酵产物液相浓度影响较大,最高液相VFAs浓度分别在发酵时间1.83天、10%TS含量和初始pH=5.5情况下得到。另外在各实验条件下,产生的VFAs组成相对稳定,乙酸是发酵产物中含量最多的酸,其次是丙酸和正丁酸。     

养殖废水沼气产气量与沼气发电量均衡问题探讨

针对沼气产气量不均衡造成发电量不稳定的问题,通过对浙江温州市某养殖废水沼气发电工程情况的经济技术分析,提出了给发酵池设置特朗布墙的保温措施与太阳能增温措施以维持池温恒定的办法,从一定程度上解决沼气产气量不均衡的问题.     

广东省沼气资源潜力与养殖场沼气工程效益分析

文章介绍了广东省养殖场的沼气工艺流程,并利用广东省2017年统计年鉴的数据,评估计算了生猪、奶牛、肉牛、羊和鸡的粪尿量及其潜在的沼气资源量.评估结果表明:2016年广东省沼气资源量为24.37亿m3,若按沼气中含有50％的甲烷气体计,则折合甲烷12.19亿m3,约占广东省同年天然气消费量的7.3％.文章以广州市花都区大...     

Simultaneous production of hydrogen and carbon nanotubes from biogas: On the design of combined process

We introduced a novel combined process of CO₂ methanation (METH) and catalytic decomposition of methane (CDM) for simultaneous production of hydrogen (H₂) and carbon nanotubes (CNTs) from biogas. In this process, biogas is catalytically upgraded into CH₄-rich gas in METH reactor using Ni/CeO₂ catalyst, and the obtained CH₄-rich gas is subsequently decomposed into H₂ and CNTs in CDM reactor over CoMo/MgO catalyst. Among the three different process scenarios proposed, the combined process with a steam condenser equipped between METH and CDM reactors could greatly improve a CNTs productivity. The CNTs production yield increased by more than 2.5-fold, maximizing at 9.08 gCNTs/gCat with a CNTs purity of 90%. The deposited carbon product was characterized as multi-walled carbon nanotubes (MWCNTs) with a surface area of 136.0 m²/g, comparable with commercial CNTs of 199.8 m²/g. The remarkable I_G/I_D ratio of 2.18 confirms a superior portion of graphitic carbon in the synthesized CNTs upon the commercial CNTs with I_G/I_D = 0.74. Notably, the CH₄ conversion reached 94.5%, while the CO₂ conversion achieved 100%, resulting in the H₂ yield and H₂ purity higher than 90%. This combined process demonstrates a promising route for production of high quality CNTs and high purity H₂ with complete CO₂ conversion using biogas as abundant renewable energy resources. In addition, the test of raw biogas showed no deactivation of catalyst, justifying the implementation of the developed process for real biogas without purification.     

添加酒糟、草木灰对猪粪厌氧发酵的影响

以猪粪为发酵原料,研究在25℃条件下分别添加不同量的酒糟、草木灰对厌氧发酵产沼气的影响,分析了厌氧发酵过程中产气速率、累积产气量、pH值、氨态氮质量浓度及甲烷含量的变化。结果表明,在猪粪中添加草木灰1 g,累积产气量大且甲烷含量高;添加酒糟5 g,累积产气量大且甲烷含量高。添加1,3,5 g草木灰,pH值呈现降低—升高—稳定的趋势,氨态氮呈现升高—降低—稳定的趋势;添加1,3,5 g酒糟后,发酵过程中的pH值和氨态氮变化规律相似,均呈现升高—降低—升高—稳定的趋势。因此,合理的酒糟、草木灰添加量是提高猪粪厌氧发酵产气量及甲烷含量的前提。