Process Characteristics of Bioga Production System with Feeding of CO_2

投加CO_2沼气生产系统工艺特点

• 批准号: 14560216
• 负责人: KITAMURA Yutaka
• 金额: $ 1.86万
• 依托单位: Shimane University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14560216/
• 关键词: Biogas; Carbon dioxide; Gas substrate; Heating with gas; Acidogenic fermentation; Leachate; Hydrolysis; バイオガス変換; メタン発酵; 汚泥返送; 二酸化炭素固定; 溶解度; 低温バイオガス発酵

The practice use of H_2/CO_2 utilizing biogas production system which can fix CO_2 into the system is in the huge demand however no useful information on the biogas system with gas substrate is available. In this study, some experiments on the heating characteristics and process stability owing to the anaerobic sludge of the gas utilizing digester is conducted to have fundamental data to design and develop the biogas production system to fix carbon dioxide from the gas substrate.In order to develop the economical methane fermentation system with gas substrate feeding, a pilot scale fermentor with a rotational gas discharge system composed of a pivot and rotational bar was constructed. The heat exchange is conducted by direct contact between the hot biogas from the bar and the slurry in the fermentor. By use of water and air instead of waste slurry and biogas in this study, the rotational and heating characteristics of the system were investigated in the points of enemy and material bal … More ance analysis. The rotation of the bar corresponding to the airflow rate and the heat transfer from the inlet air to the water were observed in the system without the gasbag or the open-air system. In the heating with the gasbag or the closed system, the water temperature increased gradually and the simulated temperature increase by the heating model fitted to the actual temperature rise. The new heating system was concluded to be feasible in practical use.The effects of leachate from a methanogenic process on acidogenic performance in a cascade process of rotational drum fermentation system (RDFS) were evaluated under mesophilic condition and a total HRT of 20 days. Using fresh soybean meal or okara as substrates, two process configurations-Cascade process 1 and 2-were employed to perform the experimental estimation. An apparent first-order hydrolysis rate constant of 15.8×10^<-3>/d for Cascade process 1 at pH values of 4.6〜5.1 and 14.7×10^<-3>/d for Cascade process 2 at pH of 5.2, which were higher than that obtained by a previous study (9.0×^<-3>/d), were obtained. The apparent VS degradation ratio ranged from 21.1 to 25.5% and total VA (as acetic acid) from 14.5 to 18.6 g/L. Occupying ratios for ionized VA increased from 30.8% to 68.5% for Cascade process 1 and to 73.3% for Cascade process 2. However, occupying ratios of acetic acid decreased from 94.3 to 72.6% for Cascade process 1 and to 43% for Cascade process 2 whereas propionic acid and butyric acid ratios increased in both acidogenic processes. Although the addition of leachate promoted hydrolysis of substrate in both processes, the adverse effects of high VA concentration on hydrolysis rate were observed in Cascade process 2, where apparent hydrolysis rate constant was slightly less than that of Cascade 1. Less

利用沼气系统固定二氧化碳的沼气系统的实际应用有着巨大的需求，但目前还没有关于沼气系统的有用信息。本研究对沼气池厌氧污泥的加热特性和工艺稳定性进行了实验研究，为设计和开发沼气发酵系统从气体基质中固定二氧化碳提供了基础数据。为了开发经济型沼气发酵系统，采用气体基质进料，建立了由枢轴和转杆组成的旋转排气系统的中试发酵罐。热交换是通过棒材中的热沼气与发酵罐中的浆液直接接触进行的。在本研究中，以水和空气代替废浆和沼气，从天敌和物质的角度考察了该系统的旋转和加热特性。…。更多的优势分析。在无气囊系统和露天系统中，观察到了棒材与空气流量对应的旋转和从入口空气到水的换热。在气囊加热和封闭系统加热中，水温逐渐升高，加热模型模拟的温升与实际温升相吻合。在中温条件下，考察了产甲烷渗滤液对转鼓发酵系统(RDFS)级联过程产酸性能的影响。以新鲜豆粕或秋葵为基质，采用两种工艺配置--串级工艺1和工艺2进行了实验估算。在pH=4.6~5.1和pH=5.2时，级联工艺1的表观一级水解速率常数分别为15.8×10~(-3)/d和14.7×10~(-3)/d，均高于前人的研究结果(9.0×10~(-3)/d)。VS表观降解率为21.1~25.5%，总VA(以乙酸计)为14.5~18.6 g/L，电离VA占有率分别从30.8%和73.3%上升到级联工艺1和级联工艺2的68.5%和73.3%，而丙酸和丁酸的占有率分别从94.3%和43%下降到72.6%和43%。虽然渗滤液的加入促进了两种工艺中底物的水解，但高浓度的VA对水解率的不利影响在级联工艺2中观察到，其表观水解速率常数略小于级联工艺1。

项目成果

Y.Kitamura, T.Liang, D.Paquin, L.Gautz: "Direct Contact Heating for Fermentor by Rotational Hot Gas Discharge System"2002 ASAE Annual International Meeting, USA. 1-5 (2002)

Y.Kitamura、T.Liang、D.Paquin、L.Gautz：“通过旋转热气排放系统直接接触加热发酵罐”2002年ASAE国际年会，美国。