NOVELTY - Device comprises a storage tank (100) for storing livestock excretion, an anaerobic digestion tank (200) for generating biogas via anaerobic fermentation of the livestock excretion, a collecting tank (120) for collecting the generated biogas, a fermentation-filtration bed (300) filled with humidity adjusting agent for fermenting mixture of organic wastewater, and introducing organic wastewater in the anaerobic digestion tank, a waterspout (400) for collecting the digestive fluid produced by fermentation of organic wastewater, and a liquefied fertilizer reservoir for storing digestive fluid.    USE - The device is useful for increasing liquid fertilizer and biogas residue by treating organic wastewater of the biogas production facility (claimed).    ADVANTAGE - The device enhances biogas yield with high quality at low coat.    DETAILED DESCRIPTION - Device comprises either a storage tank (100) for storing livestock excretion, an anaerobic digestion tank (200) for generating biogas via anaerobic fermentation of the inflowing livestock excretion from the storage tank, a collecting tank (120) for collecting the generated biogas from the anaerobic digestion tank, a fermentation-filtration bed (300) filled with humidity adjusting agent for fermenting the mixture of organic wastewater and introducing organic wastewater in the anaerobic digestion tank, a waterspout (400) for collecting the digestive fluid produced by fermentation of organic wastewater within the fermentation-filtration bed, and a liquefied fertilizer reservoir for storing the collected digestive fluid; the storage tank, the anaerobic digestion tank, the collecting tank, the fermentation-filtration bed, the waterspout, the liquefied fertilizer reservoir, and a gas moisture refining part for recovering the purified water of the generated biogas after anaerobic digestion within the anaerobic digestion tank; or the storage tank, the anaerobic digestion tank, the collecting tank, an anaerobic stabilizing tank for separating sludge and organic waste by heating the livestock excretion, supplying into the anaerobic digestion tank, the fermentation-filtration bed filled with humidity adjusting agent for fermenting the mixture of organic wastewater and introducing the generated organic wastewater in the anaerobic digestion tank and the anaerobic stabilizing tank, the waterspout, and the liquefied fertilizer reservoir. An INDEPENDENT CLAIM is also included for increasing liquid fertilizer and biogas residue by treating organic wastewater of a biogas production facility, comprising (a) collecting livestock excretion, preprocessing and storing, (b) anaerobic fermenting the livestock excretion by growing microorganism to generate biogas, (c) collecting the generated biogas, (d) introducing the organic waste into the fermentation-filtration bed, and fermenting and filtering the mixture of organic waste using the humidity adjusting agent, (e) collecting the digestive fluid of the organic wastewater, and (f) stabilizing the collected digestive fluid in to the liquid fertilizer storage tank.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic representation of the device for increasing liquid fertilizer and biogas residue by treating organic wastewater from biogas production facility (Drawing includes non-English language text).    Storage tank (100)    Collecting tank (120)    Anaerobic digestion tank (200)    Fermentation-filtration bed (300)    Waterspout (400)