Paper title: Effect of biochemical factors from mixed animal wastes feedstock in biogas production

摘要

Animal wastes can serve as the feedstock for biogas production (mainly methane) that could be used as alternative energy source. The green energy derived from animal wastes is considered to be carbon neutral and offsetting those generated from fossil fuels. In this study, an evaluation of methane production from animal wastes with different nitrogen and carbon sources was carried out. Anaerobic batch reactors containing different mixtures of animal wastes and potential inhibition sources were set up to evaluate methane potential. Biogas productions were sampled and monitored by gas chromatography and photoacoustic gas analyzer. The results showed that methane productions increased as the solid concentrations, temperature and total carbon increased. However, biogas production decreased substantial when ammonia concentrations in the feedstock were high. The addition of carbon to the feedstock provided a better substrate for methane production during anaerobic digestion of animal wastes. In addition, methane productions were the greatest when additional seed (source of acclimated microbes) was used. Methane productions were more than several times greater from reactors with feedstock amended with additional source of carbon than the ones with just animal wastes (e.g., swine, poultry or just dairy). There was no methane production in the sterile control. Thus, it appears that additional carbon source is necessary to increase methane production from animal waste anaerobic digester. Inhibitor such as ammonia appears to hinder the biomethanation in the anaerobic digestion of animal wastes for optimum methane production.