RU2001038C1 - Process for the preparation of liquid peat-humic suspension fertilizers - Google Patents

Abstract

Usage: the invention relates to agriculture. The purpose of the invention: reducing the cost of manufacturing, storing and transporting fertilizer by concentrating humic acids in it. The essence of the invention is in a method involving mixing peat with a 1.0 - 2.5% aqueous solution of potassium hydroxide, it is new that the components are mixed in a ratio of 1: (4-5), during mixing, into the mixture periodically caustic potassium is added, keeping its concentration in the solution no more than the initial one, while adding it to the mixture is stopped when the concentration of humic acids in the solution is stabilized.

Description

The invention relates to agriculture, which can be used to produce concentrated liquid and suspended peat humic fertilizers.

A known method for producing liquid complex humic fertilizers (HCSF) and suspended peat-humic fertilizers (STHU), comprising treating peat with a 2% aqueous solution of caustic potassium, peat-humic fertilizers. Specifications TU214 RSFSR 9-204-88. Ministry of Fuel Industry of the RSFSR, Republican Peat Mining Industrial Association, 1988).

There is also a known method for producing HCGF in which peat is treated with a 1.0-2.5% aqueous solution of potassium hydroxide. It has been established that at such alkali concentrations, the purest humic acids are secreted, containing the largest number of active functional groups, which are plant growth stimulants 1.

With an increase in the concentration of alkali to 3% and higher in the isolated humates, a decrease in the content of active functional groups and an increase in ash content are noted. This is explained by the fact that more specific alkaline solutions extract not only all humic substances of peat, but also the organic matter of carbohydrates, lignin, waxes, bitumen, which, although they contain a part of functional groups, are less active or even inhibitors.

The second condition for the production of HCSU and STHU is the use of such an amount of a 1.0-2.5% alkali solution so that it is sufficient not only to extract all the purest humic acids by forming potassium humates, but also to ensure a parallel formation process potassium oxide and for a residual alkali concentration in the fertilizer.

In particular, in the above solution, ZHKGU and STGU are obtained by exposure to 1000 l of a 2% aqueous solution of caustic potassium per 50 kg of peat, i.e. 20 kg of water and 0.4 kg of caustic potassium are consumed per 1 kg of peat. With ego in the obtained fertilizers, the concentration of humic acids should be at least 2 g / l in the HCS, at 5 g / l in the STU, and 13 g / l in potassium (K20) in the HCS and STG.

Based on the foregoing, it follows that although the treatment of peat with a 1.0-2.5% aqueous solution of caustic potassium and contributes to the extraction of the most active groups of humic acids, but obtained in this way ZHKGU and STGU contain a significant amount of water, which is ballast, and relatively small amount of humic

acids.

This feature of liquid and suspended peat humic fertilizers increases the costs of their manufacture, storage and transportation, because requires

Compared to concentrated fertilizers of large areas of production and storage facilities, more productive and bulk production equipment and more capacious containers

5 for storage and transportation.

You can, of course, reduce the water content in the fertilizer by its evaporation, but this method is energy intensive and for this reason is not profitable.

0 The aim of the invention is to reduce the costs of manufacturing, storing and transporting HCSU and STHU by concentrating humic acids concentrated in the fertilizer.

5 This is achieved by the fact that in the well-known

the method of producing liquid and suspended peat humic fertilizers, the movement of peat with an aqueous solution of potassium hydroxide is carried out in a ratio of 1- (4-5)

0 about the mixing process, caustic potassium is added to the mixture, maintaining its concentration in the solution no more than the initial one, while the addition of caustic potassium to the mixture is stopped until the concentration of gu5 minic acids in the solution stabilizes.

The essence of the proposed method is as follows.

Mixing peat with a 1.0-2.5% aqueous alkali solution is carried out in

0 such a ratio that produces the most concentrated peat mixture. At the same time, its consistency should be such that the mixture is not overly thickened and that it can be

5 is relatively easy to mix and pipe.

It was experimentally established that, depending on the quality and grade of peat, to obtain such a mixture, at least 4-5 parts by weight of an aqueous solution of alkali per 1 part by weight is necessary. peat. An increase in this ratio of more than 5 results in less concentrated fertilizer.

At the same time, the amount of alkali contained in the resulting mixture of such a concentration is insufficient to extract all light fractions of humic acids from peat. In particular, in the known method (see Peat-humic fertilizers ... sheet 5, table 4), 1000 l of a 2% potassium hydroxide solution, i.e. the ratio of aqueous alkali to peat is 20.

Therefore, during the interaction of peat with an alkali solution, the concentration of alkali in the mixture decreases and can ultimately reach a value at which the formation of humates stops. In this case, part of the light fractions of humic acids will remain in peat.

In order to extract all the light fractions of humates from peat, the mixture is added with the addition of dry potassium hydroxide or its concentrated solution during mixing and the alkali concentration is restored to the initial one. As a result, the evolution of humates and the formation of potassium oxide continue. As light fractions of humic acids are recovered from peat, the growth in the content of humates in the mixture slows down and finally stops. This means that the fertilizer production process is complete and the addition of caustic potassium to the solution must be stopped.

Example. Getting STGU in a known manner. 50 kg of peat is mixed with 1000 l of a 2% potassium hydroxide solution. The analysis results are as follows: the content of humic acids is 3.9 g / l: the final concentration of potassium hydroxide is 0.5-0.6%; the content of potassium (potassium oxide) is 13 g / l.

Example 2. Getting STGU the proposed method.

a) 50 kg of peat is mixed with 200 l of a 2% potassium hydroxide solution (4 kg of dry potassium hydroxide).

The analysis results are as follows: - the content of humic acids is 11.3 g / l; - The final concentration of potassium hydroxide is -0.24 g / l.

b) 3.5 kg of dry potassium hydroxide are added to a similar mixture based on an increase in its concentration to 2.0%.

The analysis results are as follows: - the content of humic acids is 20.0 g / l; - final concentration of potassium hydroxide is 0.5 g / l.

c) 3.0 kg is added to a similar mixture

dry potassium hydroxide based on an increase in its concentration to 2%.

The analysis results are as follows: - the content of humic acids is 23.0

0 g / l; - concentration of caustic potash - 1.2%.

Due to the fact that the increase in the content of humic acids in the mixture was substantially slowed down while maintaining a sufficiently high concentration of caustic potassium, the addition of dry caustic potassium was no longer done.

From a comparison of examples of obtaining STHU known to the proposed methods, we can conclude:

The concentration of humic acids in the fertilizer obtained by the proposed method is 23.0% instead of 3.0 g / l according to the known method;

the water content in the fertilizer obtained by the proposed method is 5 times less than in the fertilizer obtained in a known manner;

the total amounts of humic acids extracted with 50 kg of peat by the known and proposed methods are almost identical.

Using the proposed method for producing liquid and suspended peat-humic fertilizers provides

5 compared with the known method, the production of fertilizers more concentrated in humic acids, which significantly reduces the costs of their production, including operating equipment, storage and transportation, allows increasing the production of peat and humic fertilizers on existing equipment. (5G) USSR Copyright Certificate

5 N. 1323555 C. C 05 F 11/02, 1987.