SU1011619A1 - Process for producing liquid complex fertilizers - Google Patents

Abstract

1. METHOD FOR PREPARING LIQUID COMPLEX NUCLEAR FERTILIZERS by neutralizing extraction polyphosphoric acid with gaseous ammonia at a temperature of 270–380 ° C with subsequent dissolution of the resulting melting solution and cooling the finished product; In order to improve the quality of the product by reducing the amount of insoluble impurities in it and reducing the consumption of polyphosphoric acid, an ammonium orthophosphate solution or a mixture of orthophosphoric acid is used as an ammonia-containing solution. slots and ammonia. 2. The method according to claim 1, which is also distinguished by the fact that the ammonia-containing solution takes in the amount of 1-45% of the total amount injected.

Description

OUB CO. The invention relates to a method for producing liquid complex fertilizers widely used in agriculture. A known method of producing liquid complex fertilizers, including non-recrystallization of extraction polyphosphonic acid heated to 60 ° C, hectare, form of ammonia, dissolution of neutralization products in ammonia during and cooling of complex complex fertilizers 13. However, this method cannot be used to obtain fertilizers with stable the content of condensed forms and the consumption of polyphosphoric acid. You can’t lower it below 340.4 kg per ton of finished product. The closest to the proposed technical essence and the achieved result is a well-known method of producing liquid complex fertilizers by neutralizing extraction polyphosphoric acid with gaseous ammonia at 270-380 ° C, followed by dissolving the resulting melt with amix-containing solutions and cooling the finished product. According to this method, the extraction polyphosphoric acid is heated to 70-120 ° C and neutralized with gaseous ammonia. The molar ratio of the initial components is 2-3. The melt of poly, ammonium phosphate is dissolved in a solution of ammonia water by the addition of gaseous ammonia. For cooling the melt, the cooled finished product is introduced before dissolving or at the dissolving stage. The solution of liquid complex fertilizers is cooled in a refrigerator to 20-35 Cf. The disadvantage of this method is that the fertilizers contain insoluble impurities, which impairs the quality of the finished product, as well as high consumption of polyphosphoric acid. 340.4 kg 1 ton of finished product. The amount of insoluble impurities in the solution is determined by the sequestration coefficient C E. E. Mg-O-2.5Ae, 0 ,, o ,,. which in this case is 0.08-0.1. The purpose of the invention is to improve the quality of the product by reducing the amount of insoluble impurities in it and reducing the consumption of polyphosphoric acid. The goal is to achieve a coherent method that includes neutralizing the extraction polyphosphoric acid with gaseous ammonia at 270-380 ° C, the subsequent dissolution of the resulting ammonia-containing melt solutions and cooling the finished product / in which an ammonium-containing solution or a mixture of orthophosphoric acid is used as the ammonia-containing solution. It is advisable to take the ammoniacal solution in the amount of 1-45%. of the total amount of P O entered. The introduction of ammonium orthophosphate or a mixture of orthophosphoric acid and ammonia makes it possible to stabilize the conversion factor O ,, in solution to op: 5: about 55%. At this conversion rate, the condensed forms are present mainly in the form of a pyroform, which has the highest solubility and binding efficiency of oxides such as soluble complexes. In addition, the ammonium orthophosphates injected contain fluorine, which increases the value of the sequestration coefficient. The formation of soluble complexes of Fe, l and decreases the loss of i to 5%. The introduction of ammonium orthophosphates at the dissolution stage allows to reduce the amount of polyphosphoric acid added while maintaining the same system performance. The feasibility of the chosen amount of ammonium orthophosphates introduced into the process is illustrated in the table.

339.63

40.2

40.4

-336.94 49.9 272.77 61.5 221.00 70.6 193.20

74.1

183.74

46

84.0

79.0

4.95 58.0 2.1 0.257, 0 55.0 O

0.05

49.0

0.55 As can be seen from the table, the minimum amount of orthophosphates should be at least 1%, since this results in a noticeable decrease in the consumption of extraction polyphosphoric acid and an increase in the sequestration coefficient. Moreover, the minimum amount of injected orthophosphates is also determined by the possibility of exact dosing of the components. The maximum amount of orthophosphates should not exceed 45%, since despite the high coefficient of sequestration and large savings of polyphosphoric acid, an increase in the share of orthophosphates leads to a decrease in the coefficient of version, which causes crystallization of salts and the solution becomes fluid. The method is carried out as follows. Extraction polyphosphoric acid is heated to TO-lio C and fed into a tubular reactor, where gaseous ammonia is fed at 90-240 ° C. The reactor temperature in the reactor is 270 DLO, the molar ratio Mn ,, is 1: 2-3. Ammonium polyphosphate melts are sent from the reactor for dissolution. Before dissolving, a portion of the cooled solution of liquid complex fertilizers (the finished product is fed to the lower part of the tubular reactor or to the dissolution stage. An ammonium orthophosphate solution (or orthophosphoric acid) and an ammonia gas are supplied to the dissolution stage. The temperature at the dissolution stage is BO-EO C. The resulting solution of the liquid complex hyphenations is sent to a cooler for cooling. I return part of the solution either to the neutralization stage or to the dissolving stage. The finished product is removed from the process, the pH of the new product - 6.2–6.7, the conversion rate of the P ,, sequestration coefficient is 0.102–0.52. Using the proposed method allows obtaining liquid complex fertilizers practically free of insoluble impurities and reducing the consumption of polyphosphoric acid by 30–35 The method allows the use of orthophosphoric acid and ammonium orthophosphates obtained in the processing of phosphate raw materials containing a large amount of Mg. And one and a half oxides. To obtain 1 t of 10-34-0 brand utility equipment to the reactor, the jigging is 193.2 kg of apatite extraction polyphosphoric acid (52% kg of gaseous ammonia heated at the same time, taking into account losses of 0.1% heated to The neutralization temperature is 360 C. The resulting melt of ammonium polyphosphates with a coefficient: conversion rate - 85% is fed to dissolving in a solution of ammonium orthophosphate in the neutralization reactor, where ammonia is supplied in an amount of 26 kg, a mixture of ammonium orthophosphate in. form 55 % pulp in the amount of 45% of the total, introduced with extraction polyphosphoric acid and ammonium orthophosphates, which is 625 kg. (- 147 Kg, ammonia - 44 kt). The melting of the melt is carried out at and pH-6.5. The resulting solution of LCU is cooled in a refrigerator from 60 to. The result is 1 t of 10-34-O housing and utility services with a conversion ratio of P. 55%, sequestration coefficient - 0.52. The plant capacity is 70.6 t / h, the consumption of PPFC (per 1 ton of oil is 10-34-07 - 193 , 2 kg. PRI mme R 2. To obtain 1 t of a 10-34-0 LCU, 221.22 kg of apatite extraction polyphosphoric acid (in terms of PZR, taking into account losses of 0.1%) heated to, and simultaneously served up are loaded into the reactor kg of ammonia gas heated to. The neutralization temperature is 360 ° C. The resulting melt of ammonium polyphosphates with a conversion ratio of R. 85% is supplied to dissolve ammonium orthophosphate solutions in a reactor-neutralizer, which simultaneously serves ammonia in an amount of .26 kg, a mixture of ammonium orthophosphates in a 55% pulp in the form of a 55% pulp with EPPK and ammonium orthophosphates prepared by ammonization of apatite extraction phosphoric acid - 28%, which is 556 kg (including 119 kg of ammonia - 37 kg. Dissolving of PFA melts is carried out at 60 ° C and pH 6.6. The resulting HCU solution is cooled refrigerated ke from 60 to. As a result, 1 t of 10-34-0 brand utility services with a conversion rate of 53% and a sequestration ratio of 0.41 are obtained. The capacity is 60 tons / h, the consumption of EPFC (1 ton ZHKU) 221, 22 kg., Frozen. To obtain 1 ton of 10-34-0 grade G1SU, 337.33 kg of apatite extraction polyphosphoric acid (calculated and taking into account the loss of 0.1%) heated to 80 are loaded into the reactor. With, and at the same time serves 91 kg of gaseous ammonia, heated to 90 ° C. The neutralization temperature is 360 C. The resulting PFA melt with a P / J.O5 conversion ratio of 85% is fed to the dissolving reactor-neutralizer, where ammonia in the amount of 30 kg is simultaneously fed, extraction orthophosphoric acid from apatite is 28% in the amount of 1% of total Р2.0у - 15 kg. The dissolution of the melt is carried out at bos and pH 6.7. The resulting solution of utility services is cooled in the refrigerator from 60 to. As a result, 1 t of a 10-: 34-0 utility service utility with a conversion ratio of P. 79.1% and a coefficient of sequestration j 0.102 are obtained. The capacity is 40.4 t / h, the consumption of PPFC (according to RLOe per 1, t of utility services - 337 kg.

EXAMPLE 4 To obtain 1 t of a 10-34-0 class utility unit, 221; 22 kg of apatite extraction polyphosphoric acid, CB, is calculated for PO. and taking into account the loss of 0.1%, they heat up to and simultaneously deliver 59 kg of gaseous ammonia,

heated up. The neutralization temperature is. The resulting PFA melt with a conversion factor P {(Oj- 85% is fed to the dissolving reactor-neutralizer, where 63 kg of ammonia and Karatau extraction orthophosphoric acid are simultaneously supplied - 23% P / g (with a ratio (M O: 8 and 7. The amount of extraction orthophosphoric acid was eEg 35% of the total or 517.4 kg. Dissolution of the melt is carried out at a pH of 6.7. The resulting solution of the utility is cooled in a refrigerator from 60 to 35 C. The result is 1 ton of utility equipment of 10- 34-0

With a conversion rate of 53%,

sequestration coefficient - 0.25. Capacity is 60 t / h, flow rate 0 PFC (according to PiOg- per 1 ton 221.22 kg.

Claims (2)

('54) 1. METHOD FOR PRODUCING LIQUID COMPLEX FERTILIZERS by neutralizing extraction polyphosphoric acid with gaseous ammonia at a temperature of 270-380 ° С followed by dissolving the obtained melt with ammonia-containing solutions and cooling the finished product, which is related to the fact that , in order to improve the quality of the product by reducing the amount of insoluble impurities in it and reducing the consumption of polyphosphoric acid, an ammonium orthophosphate solution or a mixture of orthophosphoric acid is used as an ammonia-containing solution and ammonia. 2. The method according to claim 1, such as with the fact that the ammonia-containing solution is taken in an amount of 1-45% of the total amount injected ^₽ 2. ° 5 used in rural method of producing liquid fertilizer, including