In recent years, with the gradual improvement of the technical level of chemical fertilizer production equipment and the continuous development of agricultural chemical fertilizer technology and the improvement of marketing system, many countries have developed special NPK compound fertilizer based on the development of multi-variety, multi-specification NPK compound fertilizer and general NPK compound fertilizer, aiming at the soil conditions of various crops and regions, and achieved good results. NPK compound fertilizer equipment has good prospects for the production of special fertilizers.
The development of general NPK compound fertilizer and special NPK compound fertilizer complement each other, and the raw material ratio of NPK fertilizer production line is flexible. From the macro point of view, due to the large-scale factories, the production of general compound fertilizers with different nutrient distribution ratios (or adding some trace elements) for farmers to choose according to the soil and characteristics, and the use of single nutrient fertilizer (such as nitrogen fertilizer) as topdressing, to adjust the nutrient distribution ratio, can meet the needs of fertilization, this kind of compound fertilizer is the main fertilizer for large-scale production. However, from a local point of view, in view of the soil type and the special nutrient requirements of some crops such as vegetables, fruits or mulberries, the ingredients of factory production need to be adjusted. The factory can add ingredients before granulation in NPK fertilizer production line to meet the needs of various formulations.
At the same time, some special compound fertilizers, such as BB fertilizer and foliar fertilizer, can be centralized produced by small fertilizer factories. A complete BB fertilizer production line has the advantages of simple structure, low investment and low cost. It is also a good choice for small factories to invest special NPK fertilizer equipment.