TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The anaerobic digestion tank is separated by a first and second anaerobic digestion tank which includes a pH controlling device. The pH controlling device includes a transferring pipe provided upper part of the first and second anaerobic digestion tanks, with a circulating tube for adjusting the pH level of the excretion, and first anaerobic digestion tank includes an inlet for injecting the livestock excretion, and the second anaerobic digestion tank includes an outlet. The interior of first and second anaerobic digestion tanks includes an agitator with a platform, and vertically provided on both sides of the platform. The fermentation-filtration bed includes first and second fermentation-filtration beds provided according to outer wall of the anaerobic digestion tank, and the agitator mixes the moisture conditioning material and organic wastewater which is filled inside of the first and second fermentation-filtration beds. The first and second fermentation-filtration beds are a fermentation bed or a filter-bed. The lower part of the fermentation-filtration beds includes a hole for passing air and discharging the digestive fluid, a guide groove provided at top of the hole, a grid with multiple discharge holes, and a filter cloth provided between the grid and surface of the guide groove. The gas moisture refining part includes a gas induction pipe for inducing strata to generate biogas after anaerobic digestion within the anaerobic digestion tank, connected with the anaerobic digestion tank, an U-shaped cooling pipe for purifying water from cooling process of biogas induced by the gas induction pipe, an outlet for introducing the biogas in the collecting tank, flowing via the cooling pipe, and a condensed water storage tank for discharging, storing and collecting the remaining water based on requirement. The anaerobic stabilizing tank obtains the required heat source by anaerobic digestive cycle in the anaerobic digestion tank for separating livestock excretion sludge and organic waste, and supplying in anaerobic digestion tank. Preferred Method: The step (c) further comprises refining water from the biogas generated via the anaerobic digestion processing.