How to make fertilizer pellets by dry granulation?
Why chemical fertilizer plants are keen to choose twin roll extruder for granulation? This is because the double roll extrusion granulator is a “general fertilizer granulator” in fertilizer granulation production. The structure of double roll extrusion granulator is divided into three parts: granulation, crushing and screening. The whole machine is made of carbon steel structure, and the extrusion roll is made of 20 Cr Mn Ti and other special wear-resistant materials.
Roller granulator is a kind of dry granulating equipment. It is produced by non drying process at room temperature. The equipment has the advantages of less investment, quick effect and good economic benefit. The whole set of equipment layout is compact, scientific and reasonable, advanced technology. Energy saving, no waste discharge, stable operation, reliable operation and convenient maintenance. Wide adaptability of raw materials, suitable for compound fertilizer, medicine, chemical industry, feed and other raw materials granulation, product granulation rate is high.
The advantages of roller extruder granulator are low cost, stable output, suitable for all kinds of organic fertilizer, compound fertilizer, compound fertilizer granulation, eliminating the conventional drying and cooling steps. This is an ideal starting point for small businesses.
However, roller extruder granulator also has its disadvantages. After granulation, the appearance of particles is not very round, and there are angular burrs. If the shape of the finished product is very strict, you can add a fillet machine.
Advantages of roller granulator:
1. Extrusion granulation for energy saving and consumption reduction refers to granulating materials at room temperature. Compared with other methods, it does not require drying measures, such as fuel oil and natural gas.
2. There is no need to add additional binder. The common production method of compound fertilizer in China is steam granulation. After the water vapor condenses and crystallizes between the material molecules, it acts as a binder in the manufacturing process. However, during the drying process, the water inside and on the surface of the particles must be drained. Otherwise, the fertilizer is easy to stick and caking during storage. However, dry granulation does not need additional additives, only the intermolecular force of the material itself can be used, thus simplifying the process and reducing energy consumption.
3. Because the drying process is omitted, the investment is small and the rate of return is low (about 15% of the total feed volume of the extruder), the process flow is simple and the investment is small. 4。 The composition of raw materials is flexible. There are many kinds of raw materials for extrusion and granulation. At present, more than 20 kinds of materials have been successfully used in extrusion and granulation: ammonium nitrate, urea, ammonium chloride, calcium nitrate, potassium chloride and sulfuric acid. In addition, the extrusion granulation process can flexibly replace the product formula in a very short time, and a set of equipment can produce more than 30 kinds of formula products.
5. Green environmental protection, no three waste emissions, extrusion granulation consumption capacity is only electricity, environmental protection, no three waste emissions. It is in line with the basic national environmental protection policy and the development strategy of enterprise environmental protection.