Method for preparing small-molecule organic water-soluble fertilizer using biomass and its waste, and product and application thereof

A method for preparing a small-molecule organic water-soluble fertilizer, comprising the following steps:

• step (1), primarily finely crushing and finely dividing a biomass organic waste after impurity removal, evenly dividing into a pressure tank, subjecting to pressurization and pressure relief, and obtaining a slurry by back and forth collision in a collision tank;
• step (2), pouring the slurry obtained in the step (1) into a gradient pressurized mixing tank, adding trace elements and a catalyst, and gradient stirring to obtain a pre-chelation slurry;
• step (3), performing small molecule hydrolysis of pulp and complete chelation with trace elements on the pre-chelation slurry obtained in the step (2) in a gradient catalytic hydrolysis tank to obtain a fully chelated slurry by catalytic hydrolysis of small molecules;
• step (4), evenly dividing the fully chelated slurry by catalytic hydrolysis of small molecules obtained in the step (3) into three gradient reaction tanks, adding a potassium source, a nitrogen source and a phosphorus source respectively, performing gradient reaction, followed by grinding, mixing, filtering, centrifuging, filtering residue and centrifugal residue return grinding to obtain a composite nanometerized slurry;
• step (5), subjecting the composite nanometerized slurry obtained in the step (4) to vacuum evaporation and concentration to obtain a concentrated solution;
• step (6), transferring the concentrated solution obtained in the step (5) to a stabilization tank, adding a stabilizer, gradient stirring, and homogenizing ultrasonically to obtain the small-molecule organic water-soluble fertilizer;
• wherein in step (1), the pressure tanks are coupled to symmetrical positions of the collision tank respectively, each pressurized to 0.3-0.8 MPa, a quick-opening valve of the pressure tanks is opened within a time of 1-5 seconds, and the slurry in the pressure tanks collides back and forth in the collision tank through a coupled connecting pipeline;
• and wherein in step (4), the three gradient reaction tanks are independently controlled.