Optimized technology for aerobic fermentation of dairy manure to produce bioorganic fertilizer by inoculating compound microbes

An aerobic fermentation test was conducted using dairy manure and cereal husk to study the optimal fermenting technical conditions. Firstly, single factor experiment was conducted on inoculation quantity of complex microbial community, moisture content, ratio of carbon to nitrogen(C/N) and dig frequency. And then, the optimal fermenting conditions were obtained through orthogonal experiments. Secondly, the complex microbial community which contained nitrogen fixation microorganism, phosphate solubilizing microorganism and potassium dissolving microorganism, were appended in the second fermentation with inoculation quantity of 1% after 15-day main fermentation. The termination time of the second fermentation was determined by measuring the quantity variations of beneficial microorganisms. The results indicated that the optimal conditions of the main fermentation could be as follows: moisture content of 65%, ratio of carbon to nitrogen of 30:1, inoculation quantity of 3.5‰ and dig frequency of one time every four days. The main and second fermentation took 15 days and 6 days respectively. Results under the optimal fermenting conditions are as follows: materials can warm up fast and maintain a long period at a high temperature; the bioorganic fertilizer has a high degree of maturity and a short fermentation cycle; the number of effective bacteria and germination index amounts to 5.2×109 cfu/g and 96.8%, respectively.