SK278237B6 - Liquid n-mg fertilizer and manufacturing process thereof - Google Patents

Abstract

The fertilizer contains 6 to 1 weight percent of the magnesium oxide and 15 to 35 weight percent of nitrogen, whereby the amidic nitrogen and nitrate nitrogen ratio is of from 1 : 1 to 2,5 : 1 and has a value of from 6,0 to 7,5. The fertilizer is prepared by mixing of the concentrated solution of the magnesium nitrate with the crystalline or prilled urea or its solution and next, by following ammoniacalisation its pH is treated.

Description

These deficiencies are largely eliminated and the range of N-Mg fertilizers is supplemented by a fertilizer with a content of 6 20 to 1% by weight. % magnesium oxide and 15 to 35 wt. The ratio of amide to nitrogen in nitrates is from 1: 1 to 2.5: 1. A concentrated solution of magnesium nitrate is used to prepare it, which is obtained by decomposing magnesite with nitric acid and 25 followed by separation of the precipitated ferric hydroxide with ammonia.

The method of preparing a liquid N-Mg fertilizer consists of mixing 70-85% urea solution with concentrated magnesium nitrate solution with water and 90 30% and 98% ammonium nitrate solution, or the urea prilled or crystalline urea is first dissolved in the concentrated nitrate solution of magnesium and water and the hot solution are mixed with 90-98% ammonium nitrate. After cooling the liquid fertilizer to below 40 ° C, the pH is adjusted to 6.0-7.5 by ammonia.

In the preparation of liquid N-Mg fertilizer, the weight of the raw materials to be mixed is determined by the material balance of nutrients according to the composition of the produced fertilizer and 40 used raw materials. The method of preparation of some types of fertilizers is without the use of ammonium nitrate or water.

The advantage of using intermediates from fertilizers is a simple production method and lower costs.

Liquid N-Mg fertilizer must not be mixed with pesticides containing phosphates and sulphates.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The liquid N-Mg fertilizer contains 23 wt. % nitrogen and 3.5 wt. of magnesium oxide. Amide nitrogen to nitrogen ratio 2.0: 1.

Raw materials: 55

(a) a concentrated solution of magnesium nitrate of 10% by weight; % nitrogen and 8 wt. of magnesium oxide

b) 71 wt. urea solution

c) 95 wt. ammonium nitrate

(d) ammonia gas.

To produce 1 ton of fertilizer, we need 437.5 kg of concentrated magnesium nitrate solution, 463.4 kg of 71% urea solution and 991 kg of 95% ammonium nitrate. After mixing and dissolution, cool the fertilizer 65 to 30 ° C and ammoniaize to pH 7.5. Nitrogen forms in the product in% of total nitrogen:

N amidic

N in nitrate specific weight crystallization temperature pH

Example 2

66.7

33.3 1304.0 kg / m ³

- 34.6 ° C

7.5

The liquid N-Mg fertilizer contains 18.9 wt. % nitrogen and 6 wt. of magnesium oxide. Amide and nitrogen ratio in nitrates 1.5: 1.

Ingredients:

(a) a concentrated solution of magnesium nitrate containing 10% w / w; % nitrogen and 8 wt. of magnesium oxide

b) crystalline urea containing 1.7 wt. waters

(c) ammonia gas.

We prepare liquid N-Mg fertilizer by dissolving 247.3 kg of crystalline urea in 752.7 kg of concentrated magnesium nitrate solution. Ammoniacalization adjusts the pH of the fertilizer to 7.4.

Nitrogen forms in the product in% of total nitrogen:

N amidic

N in nitrate specific weight crystallization temperature pH

1350 kg / m ³ -35 ° C

7.4

Example 3

The liquid N-Mg fertilizer contains 32 wt. % nitrogen and 1 wt. of magnesium oxide. Amide and nitrogen ratio in nitrates 1.5: 1.

Ingredients:

(a) a concentrated solution of magnesium nitrate containing 10% w / w; % nitrogen and 8 wt. of magnesium oxide

b) crystalline urea containing 1.7 wt. waters

c) 95 wt. ammonium nitrate

(d) ammonia gas

To prepare 1 ton of liquid N-Mg fertilizer we need 125 kg of concentrated magnesium nitrate solution, 419.1 kg of crystalline urea, 347.4 kg of 95% ammonium nitrate and 108.5 kg of water. Cool the fertilizer to 28 ° C and ammoniaize to pH 7.3. Nitrogen forms in the product in% of total nitrogen:

N amidic

N in nitrates specific weight crystallization temperature

PH

1318 kg / m ³

-1 ° C

7.3

Example 4

The liquid N-Mg fertilizer contains 30 wt. % nitrogen and 1 wt. of magnesium oxide. The ratio of amodic nitrogen to nitrates is 1.14: 1. Raw materials:

(a) a concentrated solution of magnesium nitrate containing 10% w / w; % nitrogen and 8 wt. of magnesium oxide

b) urea adhered with a content of 0.4 wt. waters

c) 95 wt. ammonium nitrate

(d) ammonia gas

To prepare 11 liquid N-Mg fertilizer we need 125 kg of concentrated magnesium nitrate solution, 383.5 kg of 95% ammonium nitrate, 344.7 kg of urea and 146.8 kg of water. Cool the fertilizer to 25 ° C and ammoniaize to pH 7.5. Nitrogen forms in the product in% of total nitrogen:

N, amidic46.67

N in nitrates53.33 specific weight 1327 kg / m ³ crystallization temperature-13 ° C pH7.5

Industrial usability

The liquid N-Mg fertilizers produced according to the invention are used for basic soil fertilization and foliar application. It is advisable to use fertilizer on magnesium-poor soils and on nutrient-intensive crops. It can also be used to accelerate the decomposition of harvest residues (straw, bark).

Claims (2)

Liquid N-Mg fertilizer, characterized in that it contains from 6 to 1 wt. % magnesium oxide and 15 to 35 wt. nitrogen with an amide nitrogen to nitrogen ratio in nitrates of from 1: 1 to 2.5: 1, and has a pH of from 6.0 to 7.5. A method for producing a fertilizer according to claim 1, characterized by mixing 70-85% urea solution with concentrated magnesium nitrate solution, water and 90-98% ammonium nitrate solution, or urea added. or crystalline urea is first dissolved in a concentrated solution of magnesium nitrate and water, and the hot solution is mixed with 90-98% ammonium nitrate and after cooling of the liquid fertilizer below 40 ° C, the pH is adjusted by ammonia.