Policy impact analysis of penalty and reward scenarios to promote flowering cover crops using a business simulation game

Due to an increasing number of biogas plants and the positive qualities of maize as a biogas substrate, the cultivation of silage maize has risen in Germany. However, there are still various reasons for the limitation of the cultivation area of silage maize. Hence, policymakers are currently discussing various alternative biogas substrates and ways to promote their cultivation. One possible alternative is the use of special flowering cover crops with additional ecological benefits. Using a business simulation game conducted with farmers, the present study investigates whether the implementation of a reward and penalty policy will improve the uptake of flowering cover crops in the production programs of farmers. The results indicate that the implementation of these policy measures was followed by a significant increase in the cultivation area of flowering cover crops. The penalty policy leads to a stronger increase in the size of the cultivation area of flowering cover crops than the reward policy, even though the policies have the same income effect for farmers. Furthermore, the results reveal that the cultivation of flowering cover crops is influenced by various socio-demographic variables.     

CaO/PAC混合絮凝剂的沼液净化性能

厌氧发酵后产生的沼液中含有大量的有机污染物需要处理,为降低后期沼液处理工程的操作费用,改善常规絮凝剂存在的不足,本文提出向沼液中添加由氧化钙（CaO）和聚合氯化铝（PAC）组成的混合絮凝剂对沼液进行预处理,降低沼液浊度、化学需氧量（COD）和总磷（TP）质量浓度,以及强化沼液的氨氮脱除潜力,并研究了混合絮凝剂中CaO和PAC的添加顺序、质量浓度配比和总质量浓度的影响。结果表明,CaO/PAC混合絮凝剂中CaO和PAC的添加顺序对沼液净化性能的影响并不显著。降低CaO/PAC中CaO与PAC的质量浓度配比（m_CaO/m_PAC）和增加CaO/PAC总质量浓度均将会降低沼液浊度、COD含量与TP质量浓度,但以沼液pH来表征的沼液氨氮脱除潜能却随着m_CaO/m_PAC值与CaO/PAC总质量浓度的上升而增加。综合考虑混合絮凝剂对沼液的净化性能,CaO/PAC混合絮凝剂总质量浓度可选择12.5～18.75g/L,m_CaO/m_PAC值可选择（2～10）∶1。     

一种新型反应器——生物气射流循环厌氧流化床的启动与运行特性

A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed （JBILAFB）, was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose wastewater treatment. With the wastewater recycle ratio of 2.5 ： 1, the recycled wastewater with biogas could mix sludge and wastewater in the JBILAFB reactor completely. The start-up of the JBILAFB reactor could be completed in less than 70 d through maintenance of hydraulic retention time （HR~I＂） and stepwise increase of feed total organic carbon （TOC） concentration. After the start-up, with the volumetric TOC loadings of 14.3 kg·m ^-3·d^-1, the TOC removal ratio, the effluent pH, and the volatile fatty acids （VFA）/alkalinity of the JBILAFB reactor were more than 80%, close to 7.0 and less than 0.4, respectively. Moreover, CH4 was produced at more than 70% of the theoretical value, The reactor exhibited high stability under the condition of high volumetric TOC loading. Sludge granules in the JBILAFB reactor were developed during the start-up and their sizes were enlarged with the stepwise increase of volumetric TOC loadings from 0.8 kg.m^-3.d ^-1 to 14.3 kg.m^-3.d^-1. Granules, an offwhite color and a similar spherical shape, were mainly comprised of global-like bacteria. These had good methanogenic activity and settleability, which were formed probably through adhesion of the bacteria. Some inorganic metal compounds such as Fe, Ca, Mg, Al, etc. were advantageous to the formation of the granules.     

浅析当前农村沼气推广中面临的几个新问题

本文针对当前农村发生的一些新变化,论述了这些变化对沼气推广的影响,并提出了相应的应变措施。     

沼气中硫化氢气体的生物处理法

沼气中硫化氢的存在限制了沼气能源的推广。文章阐述了沼气生物脱硫法的原理、方法和可行性,介绍了该方法在国内外的研究发展现状。     

用沼渣生产腐殖酸型有机复合肥技术及前景

结合了沼渣生产腐殖酸型有机复合肥的生产实际,阐述了工艺技术路线、主要生产设备、生产技术指标及产品质量指标,分析了经济效益和社会效益,展望了生产技术的推广前景。     

农村沼气转型升级机遇与对策

我国农村沼气经过多年的发展,已经具备了一定的产业基础和发展优势,成为促进现代农业发展的重要动力和实现农村节能减排的有效载体。结合当前农村经济社会的发展需求,分析现阶段农村沼气产业发展中矛盾,进一步研究、探索沼气转型与升级对策,促进沼气可持续发展。     

水葫芦发酵产气潜力的实验研究

介绍了以水葫芦为实验原料，在25℃环境下，采用批量发酵的工艺，进行发酵产沼气实验。实验结果表明，水葫芦可以作为沼气发酵原料，其产沼气潜力为634mL／gTS或834mL／gVS。     

甲烷催化裂解制备碳纳米管过程中二氧化碳的影响

生物质发酵沼气含有高浓度CH₄,具有制备碳纳米管的潜力,但其中所含的大量CO₂对碳纳米管制备存在潜在影响. 研究了CH₄催化裂解制备碳纳米管过程中CO₂的影响,使用商用Ni基催化剂和水平管式炉装置开展碳纳米管制备试验,采用TPR、TPO、SEM、TEM等手段对催化剂和碳纳米管进行表征. 650 ℃时催化裂解效率最高,碳产物最大质量为催化剂质量的4倍,其中主要产物为多壁碳纳米管. CO₂对最佳催化裂解温度、催化裂解效率及多壁碳纳米管产量无显著影响,但CO₂的存在增加了碳纳米管内外径、长度和平滑度. 这可能是由于CH₄催化裂解产生无定形积碳,阻碍碳纳米管生长; 而CO₂与积碳反应清除积碳,促进了碳纳米管生长. 从CO₂的影响来看,沼气制备碳纳米管具有可行性.