■ Process Introduction

◎ Slow-release fertilizer is a means that new type of fertilizer which can slow or control the nutrient release rate. Include two types of slow release fertilizer and controlled release fertilizer.

Controlled and slow-release fertilizer production technology existing in our company' has the following four kinds：

(1) Wrapped type controlled and slow-release fertilizer production process (physical).

(2) Coated type controlled and slow-release fertilizer production process (physical).

(3) Slow-release fertilizer with urease inhibitors and nitrification inhibitor production process (biology method).

(4) Urea formaldehyde type controlled fertilizer production process (chemical method).

■ Process Characters

◎ Wrapped type controlled and slow-release fertilizer：A、Adopt the method of disc granulation, use water soluble nitrogen such as urea as the core, use inorganic plant nutrients (such as magnesium ammonium phosphate) with a variety of different solubility as the wrapped layer, wrap layer by layer, all ingredients of the whole wrapped fertilizer are plant nutrients, will not cause any residue pollution after applying into the soil.。B、Mix in a small amount of binder and trace elements after humic acid be activated, then wrapped it in urea granules, it not only played chemical biological effect of humic acid itself to enhance effectiveness, promote anti-adversity, improve soil, suppress soil urease and nitrifying bacteria, but also effectively control the urea release and decomposition speed. 

◎ Coated type controlled and slow-release fertilizer：Melt sulphur, resin, polyethylene, paraffin wax and ground phosphate rock as film forming material, Spray it on the urea granules or compound fertilizer granules surface inside the rotary drum equipment, form thin film on the surface of granules after cooling, release nutrient through the coat spread or the coat gradually decompose. 

◎ Urea formaldehyde type controlled fertilizer：Make the melting urea react with formaldehyde to form low water-soluble polymer, spray on other inorganic raw material layer inside rotary drum granulator, produce the granules, after seeding, it will gradually decompose and release nitrogen under the action of chemical or microorganisms.