CN1381428A - Process for preparing quickly solidifying composite fertilizer - Google Patents

Abstract

A process for preparing the fast solidified compound fertilizer incldues such steps as mixing urea, K, P and ammonium, heating to 75-85 deg.C to make it into a slurry, spraying it in oil tank for cooling and bringing heat away by circulating water, separating particles from oil by rolling sieve and vertical centrifugal separator, applying power to the surface of particle, and sieving and packaging. Its advantages are simple apparatus and low cost.

Description

Process for preparing quickly solidifying composite fertilizer

The present invention relates to a kind of production technique of composite fertilizer, particularly relate to the production technique of the quickly solidifying composite fertilizer of a kind of fusion oil cooling granulation.

Composite fertilizer is the inexorable trend of chemical fertilizer industrial development in modern age, accounted for the 70-80% of total fertilizer application amount in the country of chemical fertilizer industry prosperity, blended fertilizer is an importance of composite fertilizer development, and it is simple that it has production technique, flexible operation, production cost hangs down and characteristics such as penetration and promotion is easy, and in addition, it can also prevent the Physical Loss or Damage of fertilizer effectively, saving is prepared transportation at fertilizer, use the labor force of aspect, therefore, developed countries uses blended fertilizer quite general.1996,40.1% of 58.5% and whole fertilizer in whole composite fertilizers that the U.S. sells all were blended fertilizers, and China's blended fertilizer still is in the starting stage at present.

The employed equipment of China composite fertilizer manufacturer mainly contains following several at present: 1, disk granulation; 2, extruder grain; 3, cylinder granulation; 4, whitewashing cylinder granulation.The product that above production technique the is produced compound fertilizer of can only saying so at most is not composite fertilizer truly, in recent years, has domesticly gone out the urea smelting and spraying granulation, because a variety of causes is not promoted the use of.Above-described several technology all has severe operational environment, energy consumption height, it is big to take up an area of, operator are many, complex process and can't produce the composite fertilizer of high density.As everyone knows, raw material is quite serious to the corrosion of equipment in composite fertilizer's production process, and uses producer can't bear the equipment price that stainless steel is made, so is generally 3-5 the work-ing life of carbon steel production line.

In composite fertilizer produces, be extensive use of melt spray granulation abroad, but that it uses operation and raw material to use is quite strict, its principle be the fusing urea (or heat granular urea, make it fusion) of urea plant to 135-150 ℃ with the pump pound to reactor.Be crushed to 80 orders more than phosphorus, potassium mixing 5-8 minute, can influence material properties as overlong time.Deliver to narrow meshed placement shower nozzle then, be separated into small droplets,, become hard small-particle, divide packing through collection unit by being not less than the high tower cooler of 40m through shower nozzle.Its outward appearance rounding, smooth, this kind device are generally only built near the urea plant in order to reduce production costs, can directly use the fusing urea of urea plant, therefore for general producer, be difficult to adopt, and cost an arm and a leg, the complete assembly cost is more than ten million yuan, and domestic enterprise difficulty bears.

Domestic other enterprise discloses a kind of manufacture method of granular nitrogen-potassium composite fertilizer, can form the characteristics of eutectic mixture according to urea and Repone K, different raw material fertilizer is heated to certain temperature after metering to be mixed in a mixing tank, mixed slip enters a vibrating prilling device that has many apertures, mechanical vibration by the vibrating prilling device, fertilizer slurry becomes little globule by aperture, mat exciting force and strategy fall into the oil cooling groove with charge of oil in the certain altitude, bead drops in sedimentation in the oil, and cooling curing is the fertilizer small-particle, combine in the oil cooling bottom land, through promoting handling equipment the oil-containing granulated fertilizer is delivered to whizzer, with the oil on separating particles surface, promptly obtain granular nitrogen-potassium composite fertilizer.This method has overcome behind the little and Repone K extruder grain of urea product particle oblate particle or platy shaped particle is used for the unfavorable defective of blended fertilizer " material fertilizer "; and fertilizer nitrogen potassium ratio can be adjusted within the specific limits, to adapt to the nutritional needs of different crops.In addition, also the nutrient demand of visual crop adds a certain amount of moderate-element compound or trace compound, makes the granular nitrogen-potassium composite fertilizer that contains multi-nutrient element, also can add small amounts of pigment in the course of processing and make colored fertilizer.

The purpose of this invention is to provide a kind of production technique that changes the quickly solidifying composite fertilizer of domestic conventional process flow fully.

The present invention is achieved in that process for preparing quickly solidifying composite fertilizer of the present invention has following flow process: a. charging reaction, raw materials such as urea, potassium, phosphorus, ammonium are mixed and heated to 75 ℃-85 ℃, and make it to become slip; B. granulation is delivered to the disc type shower nozzle of rotation with slurry, splashes into oil groove, becomes particle by oil cooling; C. roller screen de-oiling, with particle by roller grizzly, again through vertical centrifugal machine particle and separating of oil; D. face powder is pounced on an amount of powder at particle surface; E. sub-sieve is packed.

Advantage of the present invention is: 1, good operational environment, the basic no dust pollution of whole process of production, non-wastewater discharge.2, production cost is low.Former 30,000 tons of production line installed powers are 120KW, coal consumption 180Kg/h, this production line installed power 65.7KW, coal consumption 130kg/h, operator 18 people/classes, these production line 13 people/classes.And workman's manipulation strength is low.3, use range is wide, the original production line can only be produced nitrogenous 20% the composite fertilizer that is no more than, full slurry process granulation production line can only be produced high-concentration compound fertilizer both at home and abroad, the composite fertilizer of the high, medium and low concentration of this production line all can produce, can produce compound (N, P, K content are more than 50%) of ultrahigh concentration through testing this production line, (the slow phase was 9 months, and controlled release fertilizer etc. can add trace element, herbal medicine, pigment also can to produce slow released fertilizer.4, smooth, the rounding of particle surface can be compared with import composite fertilizer, and the cost rate height needs returning charge hardly.5, cost is low, and this production line has been initiated in the domestic composite fertilizer machinery and adopted stainless precedent at material through the place, and price only is the cost of former carbon steel production line, in the work-ing life of having improved equipment greatly, has reduced the input again of composite fertilizer manufacturing enterprise.6, floor space is little, and the whole production line floor space is half of original production line, has reduced the factory building input of using producer.

Below in conjunction with accompanying drawing embodiments of the invention are described in further detail.

Fig. 1 is a process flow sheet of the present invention.

Process for preparing quickly solidifying composite fertilizer as shown in Figure 1 is urea, potassium, phosphorus, ammonium to be mixed and heated to lower temperature (being generally 75-85 ℃) make it to become slip, one go on foot and abroad compare at this point, for production composite fertilizer enterprise, be not subjected to the restriction of urea stoste yet, simplify production unit, reduced production cost.Slip is delivered to the disc type shower nozzle of rotation, splash into oil groove, by oil cooling, heat is taken away by recirculated water, and through roller grizzly, vertical centrifugal machine is pounced on quantitative powder to particle and separating of oil at particle surface, gets final product through the screening packing.

Claims (1)

1, a kind of process for preparing quickly solidifying composite fertilizer is characterized in that having following technical process:

A. charging reaction is mixed and heated to 75 ℃-85 ℃ with raw materials such as urea, potassium, phosphorus, ammoniums, makes it to become slip;

B. granulation is delivered to the disc type shower nozzle of rotation with slurry, splashes into oil groove, becomes particle by oil cooling;

C. roller screen de-oiling, with particle by roller grizzly, again through vertical centrifugal machine particle and separating of oil;

D. face powder is pounced on an amount of powder at particle surface;

E. sub-sieve is packed.