Investigation of Rural Biogas Project in northern part of China

Transcription

1 Advanced Materials Research Online: ISSN: , Vols , pp doi: / Trans Tech Publications, Switzerland Investigation of Rural Biogas Project in northern part of China Yue SHI 1, a, Chang-ping CHEN 1, b, Xiang-wen SUN 1, c 1 Harbin Engineering University, College of Power & Energy Engineering, 145 NAN-Tong Street, Harbin, Hei Long-Jiang Province, China a realshiyue@sohu.com b chenchangping@hrbeu.edu.cn c sxw1987@163.com Keywords: Investigation; biogas use; cold region Abstract:Problems associated with non-sustainable use of fossil fuels have led to increased awareness and widespread research into the accessibility of new and renewable energy resources. As the renewable energy, biogas should be widely used for its advantages in environmental friendly, security and efficiency. But factors in policy and environment made the utilization of biogas hard to achieve in cold areas. This article focus on the problem, make conclusions and give advices based on the analysis of the example of China s rural areas in the north. The exact information was obtained via questionnaire survey, aiming at promoting the utilization of biogas in cold areas. Introduction Many countries have attached much importance to biogas, for it can not only provide a reliable energy supply but also environmentally friendly. Biogas project gained unprecedented development since 1990s. According to the United Nations Department of Energy, methane production will rise from about 180 billion cubic meters at present to about 400 billion cubic meters in 2030, While the proportion of renewable energy it occupy will rise from the 9% to about 14%[1]. Biogas production [billion cubic meter] year biogas share in proprtion of renewable energy 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% year a b Fig. 1: Biogas development trends in the future All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-04/03/16,21:45:20)

2 Advanced Materials Research Vols In the future, the application of biogas not limited to combust as fuel will extend to the biogas fuel cells, biogas power generation and many other fields. More important biogas has an advantage in reducing the emission of carbon dioxide. As the research indicated: it's predicted that each user can reduce 1.43~2.0t carbon dioxide equivalent [3].There were nearly 40,000,000 biogas users in China nowadays 57,200,000~80,000,000 tons of carbon dioxide can be reduced each year [2]. This paper overviews the current status of biogas development, analysis the benefits, come up with objective problems it exited. At the same time, it focuses on the bottleneck of the application in cold regions. Research Methods Paid questionnaire. Xingshan County is located in western Hubei, the Yangtze River, construction of biogas in the south are very representative. The Dongling District of Shenyang, in northeast China, the situation can be as represent in cold regions. Table 1 listed the survey questionnaire. Table 1: Situation Tables of questionnaire Regions Issued shares Effective shares effective rate Xingshan Hubei Province % Dongling district Shenyang % Conducted on by Field visits. We visited the office in charge of energy biogas, gathered the information from the village cadres and grassroots cadres, the status of biogas, future, and problems were fully discussed. Results and Analysis Social benefits of biogas project. 16% 6% 41% % 4 1: Providing energy, Convenient and cheap. 2: Hygienic and Clean, Healthy Living. 3: Circular economy, protecting the ecology. 4: Others. Fig. 2: the distribution proportion of the maximal benefits brought by biogas, which is hold by the users The survey (Fig. 2) showed that 41% of the biogas users choose the item that the biogas can provide them energy and had the advantage of convenient and cheap; 37% of the users choose the

3 670 Environmental Biotechnology and Materials Engineering item which mentioned it's hygienic and clean and can also lead to a healthy life,16% choose the item which referred to that it was a circular economy and can protect the ecology.6% choose others. At present, under normal circumstances, a 10m 3 digester can produce about 1.5~1.8m 3 biogas per day[3],which was enough for the everyday use of a family of five, such as cooking,boiling and so on. According to the survey data, ordinary people primarily focused on the energy provided by the biogas, which was convenient and cheap and also made life easier. That nearly half of the users selected this item explained its popularity too. The Bottleneck and its Countermeasures in Biogas Development at the present stage At this stage, the survey of the biggest problem to influence biogas popularity showed that:(fig. 3) lacking follow-up service, difficult maintenance, high biogas pond vacancy rate occupied 41%; unqualified digester was unqualified 28%; 16% choose their own input was too large and the nation subsidizes little; 11% choose own digester management experience shortage; 4% choose another. By the analysis of the above data, we can draw a conclusion that first problem to influence biogas development was lacking follow-up service and technical support, the other was lacking investment. So increasing national investment and technical training was two basic methods to solve these two important issues. 16% 11% 4% 28% 41% : The follow-up services are behind time and it's difficult to maintain. 2: The biogas digester is unqualified. 3: The input by itself is large and the international subsidies are few. 4: The digesters themselves are Lack of self-management experience. 5: Others. Fig. 3: The distribution proportion of the problems for biogas to be universal,which is hold by the users From Fig. 4 and Fig. 5 you can see, the last few years along with the nation's strong investment, biogas of development speed is faster. Since 2001, Central government throws in RMB 1.2 billion national debt funds to use for developing the biogas construction annually, this supports being up to RMB 2.5 billion in 2008[4]. And want to solve biogas to be universal medium existent of various problem, government investment essential to have, government investment not only necessary to ensure effective at first, but also necessary to increase the subsequent protection, skills training of investment,subsequent protection and skills training should become a new input focus, in order to radically solve the present development bottlenecks.

4 Advanced Materials Research Vols Using quantity [million family] Year Government input [billion Yuan] Year Fig.4: China households using biogas development trends Fig. 5: The Chinese government invests in biogas project the last five years Prospects of cold region biogas development Status. Temperature of biogas was directly related to the fermentation. There was no gas could be generated when the temperature was too low. So in the cold region biogas cannot be used for almost four to five months[5].naturally the local people's enthusiasm to use biogas was reduced greatly,which leaded to the current low penetration in the cold regions,and the development of biogas had also been seriously lagged down. Fig. 6 showed the contrast of the penetration of biogas between South China and North China. biogas penetration rate 30% 25% 20% 15% 10% 5% 0% north chnia south china 22% 78% yes no Fig. 6: Comparison of Northern and Southern biogas penetration rate in China Fig. 7: Whether would like to use biogas If Solved technical problems Prospect. Many research institutes at present were committed to solve the technical problem of the application of biogas in the cold region. It was gratifying that after a long time of study and a series of experiments, the energy conservation and emission reduction project team of HEU(Harbin Engineering University) found the key to solve the problem[6].according to the result of the experiments, its economical analysis can be seen in the Table.2. (Unit:per year)

5 672 Environmental Biotechnology and Materials Engineering Table 2: Economic analysis of biogas engineering in the cold region Biogas pond volume 10 [m 3 ] One-time investment RMB 4000 [Yuan] Total biogas production 550~660 [m 3 ] Consumption of biogas for heating 270~330 [m 3 ] Net biogas production 280~330 [m 3 ] Save coal Save electricity Economic benefits 0.7 [t] 150~250 [kw h] RMB 350~450 [Yuan] According to the table, the economic benefits in the cold region were only half of that in other areas, which was about RMB 350~450 per year. It still can provide the users both the cheap and convenient energy. According to the Fig. 7, once the technical problem was solved, about 80% people were willing to use the biogas.so it's obvious that as soon as the problem was solved, most farmers still had confidence and anticipation in the biogas. Conclusion The reason why the common people of China focus on gas were that it made the life more convenient by providing the energy which was cheap and easy to use. Meanwhile, the gas was also deeply accepted and welcomed by its users in the aspect of environmental protection. The key to solve the problem in biogas development is investment and training. Besides pre-construction, follow-up support and investment in skills training is essential. Currently, the penetration rate of biogas in cold region was 8%, about 350~450 per year, although its economic benefit was just half of the general region. There was still a broad application prospect that the biogas could be used in cold region, after the technical bottlenecks have been solved and national investment increased. References [1] European Renewable Energy centers Agency-The Renewable Energy Barometers: Biogas Barometer [2] Dong Hongmin, Li Yu'e, Zhu Zhiping, Tao Xiuping: Greenhouse gas emission reduction potential of rural household biogas CDM project, TRANSACTIONS OF THE CHINESE SOCIETY OF AGRICULTURAL ENGINEERING (11). [3] Qiu Ling, He Wen yi: The method of calculate digester gas production according to the air pressure Energy research and utilization (1). [4] China's rural areas Renewable Energy Development Research Report (page13-16).2009 [5] YANG Yanli, HOU Jian, ZHANG Peidong, GUO Yangyao, YUAN Xianzheng: Spatial Disparities of Rural Household Biogas Development in China, RESOURCES SCIENCE (7). [6] Shi Huixian, Wang Tao, Zhu Hongguang: Heating system of biogas digester by ground-source heat pump, TRANSACTIONS OF THE CHINESE SOCIETY OF AGRICULTURAL ENGINEERING (2).

6 Environmental Biotechnology and Materials Engineering / Investigation of Rural Biogas Project in Northern Part of China / DOI References [5] YANG Yanli, HOU Jian, ZHANG Peidong, GUO Yangyao, YUAN Xianzheng: Spatial Disparities of Rural Household Biogas Development in China, RESOURCES SCIENCE (7) /j.rser