Development of high rate anaerobic digestion treating organic solid waste for methane-energy recovery

开发高效厌氧消化处理有机固体废物以回收甲烷能源

基本信息

批准号：
11794002
负责人：
OHASHI Akiyoshi
金额：
$ 9.41万
依托单位：
Nagaoka University of Technotogy
依托单位国家：
日本
项目类别：
Grant-in-Aid for University and Society Collaboration
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11794002/
关键词：
Methane Energy Anaerobic digestion Sewage treatment Molecular technique Microbiology 分子生物学下水処理

项目摘要

The aim of this study is to expand a technology of anaerobic digestion for treatment of organic solid waste such as activated sludge in sewage treatment system in order to enhance efficiency of methane gas recovery as energy. For making the efficiency bigger it was thought that biomass concentration in anaerobic digestion reactor should be increased. To investigate the biomass concentration effect a batch experiment, in which some materials supporting biofilm were installed, was conducted with activated sludge as substrate. The result indicated that biofilm having high biomass concentration could not promote biodegradation of solid waste. Tnen we examined amylase in an anaerobic digestion vial because hydrolysis enzyme was thought to play a crucial role. From the measurement of amylase we found a very important phenomenon that amylase was not released into bulk liquid as extra-cellar enzyme but it would be linked to cell membrane. This suggests that even though biomass concentration is high, hydrolysis of solid waste does not become proceed without concents of the solid waste and microorganisms. Therefore ozone treatment of solid waste was applied before fermented to improve the efficiency of methane recovery. The result revealed that the ozone treatment was effective for the hydrolysis of the solid waste and would be economically feasible. It is important for having a good idea of anaerobic digestion enhancement to understand satisfactory microbial community retained in the reactor. To analyze the microbial community molecular techniques were used. We also isolated several key novel anaerobic syntrophic bacteria and investigated these characteristics. From these results the structure and function of the microbial consortia were understood approximately half.

本研究的目的是扩展厌氧消化技术来处理污水处理系统中的活性污泥等有机固体废物，以提高甲烷气体回收作为能源的效率。为了提高效率，人们认为应该增加厌氧消化反应器中的生物质浓度。为了研究生物质浓度的影响，以活性污泥为基质进行了批量实验，其中安装了一些支持生物膜的材料。结果表明，高生物质浓度的生物膜不能促进固体废物的生物降解。然后我们检查了厌氧消化瓶中的淀粉酶，因为水解酶被认为起着至关重要的作用。从淀粉酶的测量中我们发现一个非常重要的现象，即淀粉酶不是作为细胞外酶释放到大量液体中，而是与细胞膜相连。这表明，即使生物质浓度高，如果没有固体废物和微生物的浓度，固体废物的水解也不会进行。因此，在发酵前对固体废物进行臭氧处理，以提高甲烷回收效率。结果表明，臭氧处理对固体废物的水解是有效的，并且在经济上是可行的。了解反应器中保留的令人满意的微生物群落对于了解增强厌氧消化非常重要。使用分子技术来分析微生物群落。我们还分离了几种关键的新型厌氧互养细菌并研究了这些特征。从这些结果中，我们对微生物群落的结构和功能了解了大约一半。