TH1142B - Granules with urea as the main substance And the process of producing such pellets - Google Patents

Abstract

The invention deals with urea-based pellets larger than 7 mm, which may contain contaminants. And the method of producing this type of pellets is especially suitable. For use as fertilizer for rice fields and at least 80 percent of Tablets weigh between 0.7-1.3 times the average weight of tablets. These granules consist of a layer of molten substance attached to the surrounding core substance. And has a crushing resistance of 20-40 kilograms, pellet production can By feeding the heated melt Or solution onto particles of Solid in the turntable The fed solid contains particles used Is a minority The ratio between these two currents should be between 150 and 1: 5. The ratio between the average diameter of the pellet is maintained. This is a closed process and can be multi-step. Large granulation, for example, 15 mm, should be performed in two separate steps. Separate storage tanks for particles used It is the core and the particles are fed back and converted to the stacked material, cool and sieve:

Claims (6)

1. Large granules containing urea as the main substance which may contain commonly used impurities such as formaldehyde. nutrients that plants need taking in small quantities and macronutrients, which are characterized by pellets having an average diameter greater than 7 mm and at least 80 percent of the pellets weigh in the range of 0.7-1.3 times the mean weight of the pellets and these pellets comprise With multiple melt layers covering one or more core particles and these granules have a crush resistance of 20-40 kg. 2. The large pellet containing urea as the main substance according to claim 1, which is 90-95% of the characteristics of the pellet, weighs in the range of 0.8-1.2 times the average weight of the pellet. 3. Active granulation method for making urea-containing pellets. The principle according to claim 1 or 2, with the feeding of the u solution. Warm urea with low water content or molten urea, which may be contaminated with it. and the cooled solids onto the turntable that in a slope The heated liquid solidifies on the particles that The solid is then formed into larger particles, the characteristic of which is that the heated liquid is fed onto the solid particles that are fed. entered in such a way that a small part is in the form of a detailed core and part large as feedback particles and the particles formed by this method will It is removed from the plate and cooled and the ore is oversized. and particles that are too small and use almost all of this latter part as feedback particles which will be Re-coated with warm liquid. and maintain the ratio between The average diameter of the pellets leaving the plate with the particles Use it as a axis to a value less than 3. 4. The method under Claim 3, which is specific to The used particles are fed through a separate storage tank in the while the particles are fed back through another storage tank. and the ratio between the average diameter of the pellet coming out of the plate with the particles used as the core is less than 2. 5. 1. 6. Any method of claims 3-5 which is characterized by Proceed to make pellets in a two-step process. Each stage consists of a plate, one plate, one storage tank for particle feedback, one tank for core particles and to convert piled substances. to cool and equipment for ore and using products from The first stage is the core particle for the second stage, and the core particle for the first stage is made from the particles. Oversized by crushing and ore (6 claims, 2 pages, 2 photos)