A Study On The Characteristics Of Enrichment And Culture Of Anaerobic Digestive Inoculum In Food Waste

With the economy and society developing, the production of kitchen waste has been growing rapidly recently and the environmental and social problems will be more and more serious. Therefore, it has become a worldwide hot topic that how to make the food waste harmless and recycled. Using anaerobic fermentation technology to treat kitchen waste, it not only can make the pressure of environmental pollutants emissions at random be lightened, but also the green clean energy(such as methane, etc.) will be obtained. It has important strategic significance in nowadays energy shortage.The anaerobic digestion series experiments were implemented in which the food waste used as the feedstock. The influence of different inoculum on anaerobic digestion of kitchen waste, the measurement method of anaerobic sludge activity for biogas production, enrichment culture characteristics of inoculum, and optimization of enrichment culture conditions, etc. were studied respectively. The experimental results as following:①The influence of inoculum selection on anaerobic digestion by kitchen waste was significant, and correlation between maximum specific biogas production rate and other fermentation indexes(total biogas production, biogas production during start-up period, degradation rate of VS, etc.) was significant at 0.01 level.②It showed that using maximum specific biogas production rate as an index or method of sludge activity measurement was feasible, and the value of which can be obtained by experiment.③Single factor experimental results showed that sludge selection, feeding way, temperature conditions, feeding P and K element, feeding Mg2+, activated carbon, aspergillus niger and adjustment p H value have a significant effect on the enrichment culture result of inoculum(the sludge activity after enrichment cultured).④The orthogonal experimental results showed that factor A(aspergillus niger) was the main influence factor on the total gas prodction, factor B(feeding way) was thesecondary factor, factor C(feeding P and K element) has a minimal impact on it. Sludge activity was mesured after enrichment cultured. The result of range analysis showed that factor C was the main influence factor, factor A was the secondary factor, factor B has a minimal impact on the result of enrichment culture. Statistical analysis showed that A2B1C3 was the best combination during the enrichment culture process, namely aspergillus niger feeding 2g/L, feeding method was 0.5g/d, nutrient elements were K(780 mg/L) and P(620 mg/L).