annazhao01 - 2011-10-22

Existing problems in manufacturing compound fertilizers and new technologies show up

Basic processes for manufacturing compound fertilizers are: Steam/water granulation, Chemical granulation or complex or slurry granulation, Drop forming or prilling, Compaction granulation and Dry mixing or blending. In the production process, the main machines used are compound fertilizer granulator, compound fertilizer drying machine, vibrating screen, chain crusher and so on.

Because of the water/moisture content of the raw materials and products, process and product quality problems, like increased hygroscopicity and plasticity, will often occur when fertilizers are granulated by using steam/water and chemical granulation processes; particularly when, for example SSP, TSP and/or urea is present in the product. The hygroscopicity and plasticity complicate drying, screening and crushing operations, and furthermore, the storage properties of those compound fertilizers are often inferior to those of fertilizers that do not contain these substances.

The present invention is developed to solve the granulation, product quality, and storage etc. problems in manufacturing of compound fertilizers. The present invention relates to a process for the preparation of compound fertilizers such as NPK, NK etc., where solid raw materials are mixed in a mixer and fed to a granulator, whereto hot air is also fed. The raw materials are granulated without the aid of water or any other liquid such as ammonia, phosphoric acid or sulfuric acid. Thus, the granulation is a true solid granulation process. Because water or any other liquid is not added, there is no need for drying the granulated product. Further more the physical quality of the product is good, too.

Particularly, the process of the present invention has great advantages to the known granulation methods which require higher temperatures at the drying phase. Particularly, controlling of the humidity and drying temperature is important and difficult; the high temperature may cause melting of the granulated material and it will stick to the interior walls and flights of the dryer near the discharge end. The optimal values for humidity and temperature vary greatly from product to product.

We can produce the whole set of compound fertilizer equipment, and also provide the design accroding to client's demands. We Zhengzhou Hongxing Mahcinery Co. manufactures all types of mining equipment, jaw crusher, impact crusher, sand maker, cone crusher, belt conveyor, vibrating screen, flotation machine and so on.

jaw crusher:
impact crusher:
sand maker:
cone crusher:
belt conveyor:
flotation machine: