Solar Energy Heating Technology Research On Rural Eco-Campus Biogas System

The technology which provides heat for biogas system is a hot spot in the marsh gas science, also a difficulty. The researchers devoting to study on biogas have been done massive work in heating up for anaerobic fermentation container by using biological source and coal etc. A lots of techniques of heating up have been obtained during these years. But all these methods must use the non-renewable energy, moreover easying to produce the pollution, which will be eliminated gradually in future. Therefore, the researchers all go to the inexhaustible clean energy - solar energy which was treated as heating source to increase temperature of biogas digester. Solar energy technology will certainly become a key in biogas engineering domain.The rural eco-campus biogas system is a new pattern about the biogas technology which is applied in the rural elementary and middle schools. But the pattern is applied later, many shorting and theory exist in some cases .The technological design and temperature of biogas digester in winter is difficulty in this system. Aiming at these questions, this article takes the rural middle school eco-campus as the researching object, in the foundation of optimizing biogas system, facilities and parameters of the installment have been designed .And about three month-long experiment was carried on in the Fan Jiazhai middle school .we use solar energy to increase the temperature of biogas system in this experiment and using the advanced instrument to measure temperature of biogas digester. Then the test result is analyzed from the thermodynamic aspect, this technology is carried on the synthesis appraisal from economic aspect finally. Provided the scientific basis for rural eco-campus'demonstration and the promotion.The main research work and results in this article as follows:(1) Aiming at sewage characteristic and traditional biogas system'question of rural elementary and middle schools, the technological project of the countryside middle and elementary schools' solar energy type biogas system was designed. Among them, heating technology, pre-treatment technology, flushing the toilet technology are emphatically designed in this article, and from the aspect of reducing quantity of heat to design main dimension of the biogas digester.(2) Choosing the Fan Jiazhai eco-campus demonstration school as researching object, the experiment aiming at increase the temperature of biogas digester with solar energy was carried on. In the testing, it adapts instrument of Auto-32, tests temperature of 10 spots inside and outside greenhouse, and draws various curve of temperature. This curve shows the solar energy heating system can increases the biogas digester temperature.(3)Using elementary theory of transmission of heat, the heat balance equation of biogas system is set up . And through the theoretical calculation, heat utilization efficiency of biogas syetem is analyzed .It shows that the heat utilization efficiency of biogas syetem is 16.57%.(4) Using the method of economics to appraise the solar energy double-effect heating system, comparing with the hot water boiler heating system, it shows that solar energy heating system has the good economic benefit and the environmental efficiency.