福建省农村有机废弃物及沼气潜力评估

根据2003年福建省统计年鉴统计数据,计算了福建省农村有机废弃物以及其沼气潜力。目前,我省每年可有各种畜禽粪便100.31×106t(TS=20%),可产沼气96.8亿m3;农作物秸秆10.35×106t,60%可以用来产沼气,可产沼气12亿m3。按我省120万户农户计算,户均可拥有沼气量为9080m3,可完全解决农村生活用能。     

规模化养猪场沼气发电工程实例分析

沼气发电不仅可以解决规模化养猪场畜禽污染,还可生产清洁能源,是发展可持续绿色循环农业的重要途径。以福建省福清市某规模化养猪场为例,介绍沼气产生工艺、沼气发电模式、注意问题及效益情况,为规模化养殖场沼气发电模式推广提供依据。     

用沼气法处理规模化养殖场畜禽粪便的优点及存在问题

文章分析了规模化养殖场畜禽粪便进行处理的必要性及处理难度，然后归纳出采用沼气法进行处理净化的3大优点，最后总结出采用沼气法处理畜禽粪便所存在的若干问题，提出规模化养殖场进行沼气开发的5项对策。     

规模化养殖小区沼气发电工程效益分析——以福建莆田鸿达牧业有限公司沼气发电工程为例

以福建莆田鸿达牧业有限公司沼气发电循环经济项目为实例,分析规模化养殖小区沼气发电工程的效益。结果表明,该沼气工程日处理粪污约400t,年处理量达15万t,年产沼气约300万m3,用于发电,年可发电4600MWh,每年可创收320万元;而且沼气生产所产生的固态有机复合肥和沼液,可满足养殖小区及周边村镇的蔬菜基地以及周边农田和果树的土地生产用肥需要。该项目的经济效益、生态效益和社会效益良好,是实现畜禽粪便更高利用价值的最佳途径,不仅可解决养猪场的粪便、废水污染问题,还可促进当地环境保护和农业产业的升级换代。     

福建省养殖场大中型沼气工程问题分析及建议

至2007年底,福建省猪粪沼气潜力占全省畜禽沼气资源总量83.17%,全省养猪场存栏数5000头以下占到了82.56%。对172家规模养猪场进行调查表明:43.02%沼气池容积在500～999m3之间,沼气利用率在30%以下的占到81.49%,大部分沼气排空,造成资源浪费,加剧温室效应。另一方面,沼气利用领域窄、工业化利用水平低。根据这些情况,笔者提出实行环境治理与能源资源开发利用并举方针,鼓励沼气综合利用,加强沼气科研创新和人才培养等建议。     

湖南省茶陵县农村有机废弃物资源及沼气潜力的研究

根据2007年茶陵县国民经济和社会发展统计公报数据,计算出茶陵县农村年产人畜禽粪便总量345×104t,可产沼气1.557亿m3;农作物秸秆量36.39×104t,可产沼气0.728亿m3.按茶陵县10万农户计算,户均可拥有沼气量为2280m3,可完全解决农村生活用能.但目前茶陵沼气池拥有量,还不能体现其应有沼气潜力,应大力推广农村沼气建设.     

欧盟沼气产业的新资源——能源作物

近十年来,欧盟国家的沼气产业已经成形。作为传统原料的活性污泥、填埋垃圾和畜禽粪便资源已经远远不能满足沼气的发展,沼气产业的发展对原料提出了更高的要求,沼气专用能源作物应运而生。文章介绍了德国、奥地利和丹麦等国的学者对沼气专用能源作物的筛选、发酵产气技术和工艺、替代石化燃油的潜力、CO2的减排效应以及合理地插入轮作制度等方面的研究进展。     

新疆农村有机废弃物资源量概算及沼气潜力分析

根据2005年新疆农村社会经济统计年鉴数据,计算出新疆每年产生畜禽粪便174.23×106 t,可产沼气72.49亿m3;农作物秸秆量19.85×106t,600%可以用来产沼气,可产沼气23.8亿m3.按新疆250万农户计算,户均可拥有沼气量为3 852 m3,可完全解决农村生活用能.但目前新疆拥有的沼气池数量,远远没体现其应有沼气潜力,应加快新疆农村沼气建设的步伐.     

天津市农村沼气生物质能发展概述

以天津市9个区县作为研究对象,定量分析农村沼气生物质能两大类资源——农作物秸秆和畜禽粪便的状况,根据不同农作物谷草比系数、折算标煤系数以及畜禽粪便综合利用系数,计算出天津市农村生物质能耗占全市新能源消费总量和农村生产、生活能耗比例。同时,详细分析了天津市农村沼气生物质能发展的五大利用模式,并且对全市农村户用沼气工程进行了环境效益分析。结果表明,天津市武清区、宝坻区、蓟县和静海县农作物秸秆资源量在天津市排名分列前4位,宁河县、静海县、武清区和宝坻区畜禽粪便资源占有量分列天津市的前4名,全市农村户用沼气池替代秸秆减排CO2达到1万多t。     

广东省生物质能资源潜力评估及分布特点

文章基于广东省农、林、畜牧业和规模以上工业统计数据,评估了农作物废弃物、林木生长和加工剩余物、畜禽粪便和工业有机废水废渣的能源潜力及其分布特点。研究发现：农作物废弃物的能源潜力为452.6万～1 207.0万t标煤,资源量最高的地区是湛江;林木生长和加工剩余物的能源潜力为545.5万～642.5万t标煤,资源量最高的地区是肇庆;畜禽粪便的能源潜力为313.8万t标煤,资源量最高的地区是茂名;工业有机废水废渣的能源潜力为7.8万～89.8万t标煤,资源量最高的地区是东莞。广东省生物质能若得到全面开发,可提供超过7.2%的全省能源消费量的潜力。     

规模养殖场沼气工程基本情况调查

调查了我省部分大中型养殖场的基本情况,养殖场粪便污水的处理及利用现状,沼气工程在规模养殖场中的应用现状,以及沼气工程的应用前景等;并对利用沼气工程处理养殖场禽畜粪便的下一步推广工作提出了若干建议。     

川渝养殖场沼气工程运行状况与沼液生物学特性研究

为探索沼气工程运行状况、沼液理化性质及微生物群落结构差异,对川渝9个养殖场沼气工程进行调查与采样分析,利用16S rRNA基因扩增子高通量测序技术研究沼液中微生物群落组成及多样性。结果表明,川渝地区养殖场沼气工程以处理养殖场废水为主,不以产能为目的,总氮(TN)、总磷(TP)、NH+4和化学需氧量(CODCr)等理化指标在猪场和牛场沼液之间无显著差异。14个沼液样品中厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、变形菌门(Proteobacteria)、互养菌门(Synergistetes)和疣微菌门(Verrucomicrobia)是主导微生物,这5大类细菌占细菌克隆总数的84%以上。猪场沼气工程Proteobacteria相对丰度在45.0%~69.3%之间,显著高于牛场,而牛场沼液中Firmicutes及Bacteroidetes占主要优势,两者相对丰度之和的平均值为58.4%。沼液中古菌以甲烷微菌纲(Methanomicrobia)、甲烷杆菌纲(Methanobacteria)占优,且Methanomicrobia丰度在2类养殖场间存在显著差异;猪场沼液中Methanosaeta占绝对优势,达到84.1%~94.4%,而Methanosarcina丰度极少。进一步分析,结果显示,沼液铵磷比与Firmicutes相对丰度、丰富度指数(Chao1)及多样性指数(Shannon)都存在显著的相关性。沼液中群落主坐标分析及聚类分析均可准确辨识猪场沼气工程、运行状况良好及运行状况欠佳的牛场沼气工程,可为养殖场粪污治理效果评价提供科学依据。     

Insights into the production potential and trends of China's rural biogas

China, one of the countries in the world abundant in agricultural wastes, has a great potential for rural biogas production. As a strategy for building a new socialist countryside and sustainable agriculture in rural China, the development of biogas is an important means to convert agricultural wastes to clean and safe energy, thereby reducing the need for fossil fuel and alleviating environmental pollution. This study presents an assessment of the biogas production potential, its current development state, and perspectives of agricultural wastes in rural China. Estimated data show that annual biogas potential from agricultural wastes is approximately (3350.58 ± 669.28) × 10⁸ m³ (equal to 239.22 ± 47.78 million tons of equivalent standard coal); such potential has been underutilized in the past. By analyzing and summarizing the direction for future development and various benefits of rural biogas in China, we present burning questions and countermeasures for biogas development and recommend that the future development of rural biogas in China should focus on both household‐scale and large‐scale development, giving priority to the establishment of large‐scale biogas engineering and biogas plants, improvement of biogas comprehensive utilization level, and construction of a reticular model of systemized green agricultural engineering linked with biogas to solve completely the problem of agricultural waste accumulation and improve the living conditions in rural China. Copyright © 2015 John Wiley & Sons, Ltd.     

沼气发酵猪粪管理系统对温室气体排放的影响

基于生命周期清单分析以及清洁发展机制,引入"碳足迹"概念,对我国散养猪以及规模化养猪场引入沼气发酵系统后猪粪管理系统温室气体排放及减排进行了估算。农户散养猪粪处理系统中,12 m3沼气池厌氧发酵过程碳足迹为223.40 kg CO2e/a,沼气代替原煤燃烧减少444.33 kg CO2e/a温室气体,沼气发酵净减少220.93 kg CO2e/a温室气体,我国散养生猪产生的猪粪以此沼气池发酵可减少温室气体20 984.62 Gg CO2e/a;分析运行规模约1 000 m3大型沼气工程的碳足迹,保守估计为2 835.32 t CO2e/a,运行沼气工程替代煤炭以及减少猪粪排放的温室气体共约2 914.23 t CO2e/a,故沼气工程年减少温室气体78.91 t CO2e,该项目共可减排1 578.20 t CO2e。在猪粪管理系统中采用沼气发酵系统可以更好地促进温室气体减排的进行。     

沼肥对保护地番茄生长发育及其产量的影响

采用二裂式区组设计的方法，以番茄为供试作物，以沼肥（沼液、沼渣）、猪粪和化肥为肥料，研究了不同施肥措施对番茄生长发育及其产量的影响。结果表明：与施用化肥相比，施用沼液的番茄植株平均株高及根系体积有所增加，番茄产量略有降低；与施用猪粪相比，施用沼渣可促进植株茎秆的健壮生长及根系发育，番茄产量提高20．8％；与沼渣和化肥配合施用相比，沼渣与沼液配合施用促进了番茄植株的生长发育，其植株生长稳健，根系发达，而且番茄产量增加；与猪粪和化肥配合施用相比，猪粪与沼液配合施用促进了番茄植株的生长发育，其株高较高、茎秆粗壮、根系发达，但番茄产量下降。     

Using renewable energy technologies for domestic cooking in India: a methodology for potential estimation

An attempt has been made to estimate the potential of using biogas plants, solar cookers and improved cookstoves for domestic cooking in India. Based on 1991 statistics on the bovine population and ownership pattern, the potential number of family size biogas plants comes out to be around 38 million in the optimistic scenario whereas, in the realistic scenario it is around 29 million. The potential of improved cookstoves is estimated at about 90 million and that of solar cookers is estimated at about 75 million.     

Integrating animal manure-based bioenergy production with invasive species control: A case study at Tongren Pig Farm in China

Integrated approach and bioresource engineering are often required to deal with multiple and interactive environmental problems for sustainable development at local and regional scales. Pig farming has flourished with fast growing economy and increasing human demands for meat in China. Water hyacinth (Eichhornia crassipes), a noxious invasive species, has encroached into most of the local rivers and lakes. Both the wastes from the booming pig farms as well as the massive plant materials of water hyacinth have caused a range of serious ecological and environmental problems. Here we present an integrated sustainable, ecological and experimental study that was designed to deal with these two problems simultaneously. Our experimental results showed that the mixtures of water hyacinth with pig manure consistently had much higher biogas production than pig manure alone, and that the highest biogas production was achieved when 15% of the fermentation substrates were water hyacinth. Our analysis further revealed that the changing C/N ratio and the lignin content in the fermentation feedstock due to the addition of water hyacinth might be two important factors affecting the biogas production. We also found that the solar-powered water-heating unit significantly increased the biogas production (especially in winter time). Overall, the project proved to be successful ecologically and socially. Through such an integrated approach and bioresource engineering, wastes are treated, energy is harvested, and the environment is protected.     

Fuel processing of biogas for small fuel cell power plants

Biogas has a huge potential as fuel for fuel cell power plants. In the present work developments in fuel processing of biogas for a phosphoric acid fuel cell power plant to be located in rural India are described. Experimental work including steam reforming and shift conversion of biogas and methane has been carried out in a laboratory development unit. It is confirmed that biogas is not only a useful fuel but also that the carbon dioxide in biogas has a positive effect on methane conversion. The biogas fuel cell power plant will give a high electrical efficiency on the small scale of biogas units.     

Effect of thermal, chemical and thermo-chemical pre-treatments to enhance methane production

The rise in oil price triggered the exploration and enhancement of various renewable energy sources. Producing biogas from organic waste is not only providing a clean sustainable indigenous fuel to the number of on-farm digesters in Europe, but also reducing the ecological and environmental deterioration. The lignocellulosic substrates are not completely biodegraded in anaerobic digesters operating at commercial scale due to their complex physical and chemical structure, which result in meager energy recovery in terms of methane yield. The focus of this study is to investigate the effect of pre-treatments: thermal, thermo-chemical and chemical pre-treatments on the biogas and methane potential of dewatered pig manure. A laboratory scale batch digester is used for these pre-treatments at different temperature range (25 °C-150 °C). Results showed that thermo-chemical pretreatment has high effect on biogas and methane potential in the temperature range (25–100 °C). Maximum enhancement is observed at 70 °C with increase of 78% biogas and 60% methane production. Thermal pretreatment also showed enhancement in the temperature range (50–10 °C), with maximum enhancement at 100 °C having 28% biogas and 25% methane increase.