Research On Dry Anaerobic Fermentation Technology Of Coconut Wastes

With the development of the society, demand for energy has been widened. In various kinds of alternative energy sources, presently, biomass energy was widely used in country for generating electricity and heating addition because of its character of safety and stability. In tropical areas of China, the abundant coconut resources are human’s important energy crop. But technologies of applying coconut lag behind relatively so that coconut wastes were abandoned or fired anywhere. This way caused waste of resources and environment pollution. In order to solve this problem, based on present fiber resources’recycle method, we put forward that using coconut wastes to get biogas through dry anaerobic fermentation technology. This process mode can solve the environment pollution from coconut wastes mismanagement and can recycle the waste resources; at the same time, this process mode is significant for the construction of new countryside in China and energy sustainable development.Firstly, we started the experimental study about coconut wastes’composition properties and acidification. Monitoring the PH through dry anaerobic fermentation process, we found that coconut wastes could be acidified well, but volatile fatty acids were accumulated easily. The value of PH rapidly decreased and fermentation speed slowed down. So we should monitor and adjust the value of PH in fermentation. Based on coconut wastes’composition properties and acidification property, we used coconut wastes as fermentation material to do experiment combining with dry anaerobic fermentation technology and analyzed the feasibility of the test, at the same time, the key factors of processing the coconut wastes by dry anaerobic fermentation technology are analyzed. it indicated that coconut wastes have proficiency for producing biogas. Coconut wastes as fermentation material, the biogas was very low yields. Adding appropriate amount of inoculum would improve biogas production and quicken the fermentation starting speed. Appropriate fermentation temperature could enhance the anaerophytes’enzyme activity, magnify the organic digestion and prevent speed reduction to increase methane content of generated biogas. So arranging inoculum concentration and fermentation temperature reasonably in fermentation process will make coconut wastes resources rationalized used.For discussing the pretreatment influence through coconut wastes’dry anaerobic fermentation, we used6%NaOH and10%NH3·H2O to dispose coconut wastes. It indicated that coconut wastes with mechanical pretreatment could raise the fermentation speed, improve biogas production and shorten the incubation period. The best ratio of C/N in coconut wastes’ dry anaerobic fermentation process is25:1. Coconut wastes with6%NaOH pretreatment produced gas relatively stable, and cumulative gas was higher.These studies provided the theoretical foundation for coconut wastes’ dry anaerobic fermentation technology’s practical application. Not only did we solve the environment pollution caused by littering or burning anywhere, but also we improved coconut wastes resources’recycle use ratio.We used orthogonal array to do experiment of coconut wastes’ dry anaerobic fermentation. In fermentation, biogas production acted as test index and inoculum size, fermentation temperature and pretreatment acted as impact factors. Through Variance analysis and intuitive analysis of test result, we known the influence level of each key factor in experiment coconut wastes’ dry anaerobic fermentation, at the same time, the key factor of fermentation process was optimized and the best combination of the key factors was obtained.