NOVELTY - Converting animal, vegetable and food by-products into useful bio-gas and fertilizer comprises: (a) anaerobically digesting or breaking down by-products to produce bio-gas; (b) collecting and storing the bio-gas into a tank; (c) removing ammonia from the effluent; (d) absorbing ammonia to form ammonium solution; and (e) separating the effluent into liquid and solid effluents.    USE - For converting animal, vegetable and food by-products from food, meat, poultry and rendering plants, into useful bio-gas and fertilizer and/or soil amendment products. The bio-gas is used as fuel for various energy recovery devices such as boilers for steam generation, gas engine generator systems for power generation.    ADVANTAGE - The animal, vegetable and food by-product materials are converted into useful bio-gas and fertilizer and/or soil amendment products. A portion of the effluent from the anaerobic treatment unit is recycled back to anaerobic treatment unit or conditioning tank or otherwise mixed with the influent, to enhance anaerobic digestion. A stable and efficient digestion is enabled by infusing bugs (bacteria) and nutrients from solids to the influent. The by-product treatment process produces a base grade liquid fertilizer solution or used as an ingredient for producing other end-use fertilizer. The products (ammonium sulfate fertilizer solution or purified ammonium sulfate crystal products), is used as an direct fertilizer product or as an ingredient in fertilizer materials. Limited work performed on the waste biosolids stream yield an excellent fertilizer and/or soil amendment material. The biosolids contain significant levels of nitrogen, phosphorus and other trace nutrients necessary for plant growth.    DETAILED DESCRIPTION - Converting animal, vegetable and food by-products into useful bio-gas and fertilizer comprises:    (i) anaerobically digesting or breaking down by-products to produce bio-gas containing methane and effluent;    (ii) collecting and storing the bio-gas into a tank;    (iii) transferring the effluent to an ammonia stripper (50) to remove ammonia from the effluent;    (iv) transferring ammonia vapor from stripper to ammonia absorption unit (70) to absorb ammonia component into an aqueous solution to form ammonium solution; and    (v) separating the effluent from ammonia stripper into liquid and solid effluents.    An INDEPENDENT CLAIM is included for a system for converting animal, vegetable and food by-products into useful bio-gas and fertilizer.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of the food, animal and vegetable by-product treatment system.    Ammonia stripper (50)    Ammonia absorption unit (70)