Humic acid coated fertilizer: slow release and synergistic total nutrition

BB fertilizer, the full name is bulk mixed fertilizer. It is a kind of compound fertilizer formed by mixing several kinds of granular single fertilizer or compound fertilizer according to a certain proportion. Its advantages are: comprehensive nutrients, high concentration, significant increase in production and cost saving, strong pertinence; simple processing, low production cost, no pollution; flexible formula. Humic acid coated fertilizer is a total nutrient fertilizer, slow release and synergistic BB fertilizer, and is suitable for mechanical application. These three characteristics determine that the fertilizer has four characteristics: fertilizer saving, water saving, labor saving and yield increasing. Humic acid coated fertilizer with slow release and synergistic function uses three series of coating materials to coat large granular urea, granular ammonium phosphate and pellet granulated potash fertilizer respectively, so as to realize the "promotion and control separation" of the treatment of the three major elements. to achieve the purpose of "controlling nitrogen, promoting phosphorus and preserving potassium". As far as "nitrogen control" is concerned, the coating material has been promoted from the single control of nutrient dissolution rate of general coated slow-controlled fertilizer to an integrated system of delayed dissolution, controlled dissolution and diffusion control combined with urease or nitrification inhibition. Through the different coating times (layers), the products with different slow-release periods were obtained to meet the changes of nutrient demand in the whole growth period of different crops. As far as "promoting phosphorus" is concerned, it can effectively reduce the fixation of soil ions to phosphorus, increase the movement of phosphorus in the soil and stimulate the absorption of phosphorus by crops. As far as "potassium preservation" is concerned, it can effectively reduce the probability of potassium ions being fixed by lattice and activate mineral potassium elements in soil. With the combination of the technological concept of promoting and controlling separation and the production mode of BB fertilizer, the mode of total nutrient controlled release or only controlled release nitrogen of general slow and controlled release fertilizer was changed, and a new type of BB fertilizer product with slow release + efficiency was formed. The supply of total nutrition means to ensure the effective supply and uniform distribution of medium and trace elements on the premise of proportional and adequate supply of a large number of elements. The process mode of humic acid coated fertilizer provides the possibility for the effective supply and uniform distribution of medium and trace elements. In the production process of coating materials, medium and trace elements are added to the mixture of humic acid and organic hydrophilic polymer to form a complex state, which is beneficial to the absorption and utilization of crops. At the same time, the coating materials containing medium and trace elements were coated on the surface of nitrogen, phosphorus and potassium granular fertilizers, and along with their uniform distribution in the soil, the problem of uneven topdressing of trace elements was solved and became a real "total nutrition" BB fertilizer. Suitable for mechanical application of BB fertilizer, humic acid coated fertilizer adopts the technical concept of promoting and controlling separation, and the process of graded treatment and utilization is adopted in the production process design, that is, in the process of granulation of large granular urea, granular ammonium phosphate and powdered potash fertilizer, the screening process is added to form semi-finished products with large, medium and small particle sizes, and then the semi-finished products with similar particle sizes are mixed into soil testing formula fertilizer. So as to improve the evenness index of fertilizer.