In-situ conversion method for simultaneously preparing biodiesel and animal feed by taking animal wastes as raw materials

The invention discloses an in-situ conversion method for simultaneously preparing biodiesel and an animal feed by taking animal wastes as raw materials. The used animal wastes can be used for simultaneously preparing the biodiesel and the animal feed without pretreatment such as grease extraction, refining purification and the like. The method specifically comprises the following steps: firstly, drying cleaned animal wastes, then homogenizing or crushing, then adding a cosolvent and a sulfuric acid-methanol solution, then carrying out an in-situ transesterification reaction; standing after thereaction is finished, filtering the obtained lower-layer phase, cleaning and drying obtained waste residues to obtain the animal feed; washing the upper-layer phase with water, removing impurities, concentrating, and drying to obtain the biodiesel. The cost of oil extraction and refining in the traditional biodiesel preparation process can be saved, the biodiesel with higher purity can be prepared, the byproduct namely t