The followings will do a great help for you.
There are two methods you can apply to produce the urea-based compound fertilizer. One is the agglomerate granulation, and the other is blending method.The specific description are as follows.
The Agglomeration And Granulation
Before granulation, you should crush urea, ammonium phosphate,potassium chloride and others by the crushing machine at first.Then, you can feed them into the granulation machine.With the help of steam or liquid, raw materials will gradually form granules under the mechanical action of the granulator. In order to ensure the strength of fertilizer particles, you can add some granulation additives, such as formaldehyde, gypsum, etc. to improve the physical properties of the product. When there are magnesium elements in your fertilizer formula, you should supplement magnesium hydroxide. You can also add the nitrification inhibitors,pesticides and herbicides into the raw materials. The Blending Method