Solar Heat Pipe Heating System In The Application Of Biogas Fermentation

Anaerobic fermentation to produce biogas is a efficient method to usingbiomass to produce energy. In the various factors of methane fermentation,temperature affects the biogas production greatly, and temperature has become thebottleneck of the development of biogas industry. In order to achieve the temperatureto keep the fermentation progress well, many researchers have carried out lots of workin this field, but there is no direct heating manner. In this paper, with heat pipe as heattransfer element we carried out experiments on solar heat pipe heating system (SHPHS)for biogas fermentation and studied the efficiency of the system.1. We designed the (SHPHS), and worked out the energy analysis andcalculation of heat exchange system, heating system and fermentation system. And wederived the parameters of SHPHS’s design parameters.2. Simulation experiments. a. During the winter, sunny day in the heat exchangersystem shutdown in the case, the collector terminal unit (heat pipe condenser) toachieve36℃; biogas for heat pipe solar heating system for warming effect analysis,biogas daily average temperature3℃, night cooling1.2℃; cloudy with lightsimulation experiments, in the case of the heat exchanger system is shut down, thecollector terminal device can achieve42℃; biogas for heat pipe solar heating systemfor warming effect analysis, the average daily increase in four digesters4℃, the nightcooling0.8℃. b. In the spring, sunny day in the heat exchanger system is turned off,the collector terminal unit (heat pipe condenser) to achieve43℃; biogas for heat pipesolar heating system for warming effect analysis, biogas daily average temperature6℃,the night cooling1.2℃.3. Cow dung as feedstock for anaerobic fermentation experiments.Thefermentation broth was175L and the total solid concentration of the broth was6%. a.The initial temperature of biogas fermentation system was21.7℃, under proper systemoperation, system fermentation temperature rose a gradient daytime, as the liquidtemperature rising gradient would gradually become smaller, the temperature achievedto38℃after stabilizing, Due to continuous cloudy day fermentation temperature was reduced to an average of about33.5℃, sunny collector again after two days to achievearound38℃, the fermentation process temperature could be maintained at38℃. Themethane content of gas components continued to rise as the fermentation, the methanecontent stabilized at70%, the carbon dioxide content increased gradually as thefermentation then reduced gradually, carbon dioxide remained at17%.Fermentationsystem equipment was able to normal operation, sunny day daily average collector5℃,the night cooling0.6℃, cloudy system could not be heating, cooling1.2℃daily，Dailytemperature insulation system works well, fermentation test to function properly, thesystem fermentation running effect was remarkable.4. Finally, we worked on energy and economic analysis of SHPHS, and exploredits practical applicability and its market.