Preparation method of matrix coal gangue and seedling raising matrix based on coal gangue

The invention discloses a preparation method of matrix coal gangue and a seedling raising matrix based on the coal gangue, and the preparation method of the matrix coal gangue comprises the following steps: crushing the coal gangue to obtain coal gangue particles, and mixing the coal gangue particles with different size fractions according to a certain proportion; the method comprises the following steps: mixing biomass and water, adding the mixture into a high-pressure hydrothermal reaction kettle, carrying out hydrothermal carbonization reaction, and carrying out solid-liquid separation to obtain solid hydrothermal carbon and a hydrothermal solution; the coal gangue mixed particles, the hydrothermal carbon and the soil are fully mixed, and the matrix coal gangue is prepared. And mixing the obtained coal gangue matrix with a hydrothermal carbonization solution and a small amount of chemical fertilizer to obtain the seedling culture matrix. According to the method, organic matters, oxygen-containing functiona