SU971833A1 - Process for producing complex fertilizer - Google Patents

Description

This invention relates to a technique for producing complex fertilizers widely used in agriculture.

A known method for producing a slow-acting phosphate fertilizer of phosphorite flour, including enrichment and grinding of easily decomposable phosphate ores 1.

"

The disadvantage of this method is the unsatisfactory physical (highly powdered powder) and agrochemical qualities of the product — a single-component fertilizer containing phosphorus in a difficult-to-digest plant form,

The closest in technical essence and the achieved result to the proposed one is the method of crawling complex fertilizer by grinding phosphate rock, mixing the phosphate mineral salt, granulating and drying the pulp. According to this method, CWS or KSe is used as a mineral salt mixed with ammonium nitrate. At the same time, the salt is introduced in the amount of 0.05-0% by weight. am (or KjO including nitrogen ammonium nitrate} per 1 wt. h. phosphate 2},

The disadvantage of this method is that the content of the digestible form does not exceed 35% of the total amount of P2O5 g contained in the fertilizer.

The purpose of the invention is to increase the content of the assimilable form of PjOj in fertilizer.

This goal is achieved by the fact that

10 method for producing complex fertilizer by grinding phosphate rock with mineral salts, granulating and drying the pulp; sulfate is used as a mineral salt

15 ammonium, taken in the amount of 0.51, 2 weight. h, nitrogen to 1 weight. including phosphorus thioxide.

In this case, ammonium sulphate is taken in the form of a solution or suspension and introduced

20 into phosphate flour before the formation of a pulp with F T (1-3.5): 1, and before pelleting, the pulp is kept under stirring for 0.5-3 hours at 50-90 C.

25

The quantitative limit of the introduced ammonium sulfate is due to the fact that its introduction is less than 0.5 weight. hours (nitrogen relative to phosphorus pentoxide) does not increase enough

30 digestible forms in fertilizer, and

the introduction of more than 1.2 weight. h neeffekfMBHO.

In addition, this quantity corresponds to a favorable agrochemical point of view

nutritional components in fertilizer. In tab. 1 shows the degree of recovery into an absorptive form depending on the amount of ammonium sulfate added, as well as data by a known method.

The ratio of N: P205

(KjO

; known)

1.Phosphoric Flour Original

2. Phosphoritic flour with potassium chloride (prototype)

3. Phosphoritic flour with the lower limit of the holding temperature of the pulp () due to the fact that when it decreases, the fraction of the acceptable form of PjOj in the fertilizer decreases, and above 90 ° C the evaporation increases significantly. Shutter speed less than 0.5 hours is insufficient, and above 3 hours, it is not appropriate. Example 1. In the reactor 100 watts are mixed. phosphoric flour composition,%: P2O5 - 30:, CaO - 42, MDO - 2.7 and 344 incl. ammonium sulfate solution concentration of 50%. The formed pulp (L: T 3.5: 1) is maintained at and under constant stirring for 2 hours, then granulated and dried. 275 are obtained in L of the finished product of composition,% - l P-, O (–7.4, -10.9,. N — 13.1 (N 1.2). Example 2. In the reactor, 100 h.h. phosphate flour of the composition indicated in example 1 and 120 ppm of ammonium sulphate suspension. The formed pulp (L: T 1: 1) is kept under constant stirring for 3 hours, then granulated and dried. .ch, of the finished product of composition,%: - 17.5, PjOf:, St N - 8.7 (N: P-jOf, 0.5: 1). Example 3. In a reactor, 100 parts by weight of phospholite are mixed flour is the degree of extraction

PyOs and digestible

sixteen

Claims (2)

22-35 tava,% 20.5, CaO - 33, - 3.7 and 203 incl. ammonium sulfate solution concentration 48%. The resulting pulp (L: T i 1: 2) is kept at 70 ° C for 0.5 hours, and then granulated and dried. Poluchiaot 200 B.ch. finished product composition,%: total - 10/5 / Pa ° sb - 6.2, N - 9.9 {N Р7О5 1: 1). The proposed method allows to obtain complex fertilizers that do not contain chlorine and to increase by 1.3-2 times the content of the assimilable form P} in the fertilizer. Claim 1. A method of obtaining a complex fertilizer by grinding phosphorites, mixing the formed phosphorus flour with mineral salts, granulating and drying the pulp, characterized in that ammonium sulfate is used to increase the content of the digestible form and the fertilizer , taken in the amount of 0.5 -1.2 weight.h. nitrogen to 1 weight.h. phosphorus pentoxide. 2. Method POP.1, characterized in that the sulfate a1 "4 they are taken as a solution or suspension, is introduced into the phosphate rock prior to processing" 979733 " calling pulp with F: T (1-3.5): 1, ai. pozin ME Mineral technology, pulp before granulation of high salt, Chemistry, 1970, Part 2, p. 819. “Ive with stirring for. R, -5 - 3 hours at 50-9. CL, 2, Ratobylska A.D. Ovoga, Sources of Information, Schenye Phosphate Ores, Nedra, 1979, taken into account when expertly 5 sec. 165 (prototype).