RU2373262C2 - Method of producing fuel granules - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: method of producing fuel granules from organic fibrous material includes breakage of organic fibrous material to 0.25-0.15 mm, moistening and heating are combined and put under the steam treatment heated to 130-180°C under the pressure from 4 to 5 atm, and the compaction of the material obtained is made in the matrixes with the proportion of diametre and length pf the channel 7:78-80.

EFFECT: enlargement of the range of the solid-propellant thermal sources, utilisation of the waste products of the millet and improvement of the environment conditions.

2 cl, 2 ex

Description

The present invention relates to methods for producing solid fuels of vegetable origin and can be used for industrial and domestic needs and in the fuel industry.

The creation of inexpensive and environmentally friendly fuels with high energy characteristics from production waste is an urgent problem at the present time. When creating such fuel, the task of disposing of waste generated during the processing of grain crops is also solved, for example, when millet is obtained from millet, up to 30% of millet husk, which is a scaly shell, is formed.

A known method of producing molded products, mainly fuel briquettes (AS USSR No. 763454, class C10L 5/44, publ. 09/15/1980).

By the proposed method, it is possible to obtain fuel in the form of briquettes from reed cut waste. The method is ineffective for processing waste containing a small amount of organic compounds that contribute to the formation of stable durable granules, such as waste from millet production.

A known method of producing fuel briquettes (AS USSR No. 1458377, class C10L 5/44, publ. 02.15.1989).

According to the known method, wood waste ground to 0.1-0.5 mm is heated to 90-100 ° C for 3-8 minutes and mixed with 4-25 wt.% Peat dust. The mixture is pressed under pressure of 40-70 MPa in a matrix heated to 180-210 ° C.

The disadvantages of this method are: the lack of disposal of waste generated during the processing of grain crops, since in this case, for the manufacture of fuel briquettes, in addition to the main source material (sawdust), a binder material is used - peat. Consequently, the cost of the product increases, the process is lengthened and complicated, and the combustion products have a more complex structure, which means that they pollute the environment more.

A fuel agent is known (RF Patent No. 2237083, class C10L 5/44, publ. 2004.09.27).

The fuel product contains a solid base of organic origin and a binder, while buckwheat peeling waste is used as a solid base, and buckwheat peeling flour waste, natural dust and sawdust are used as a binder

A disadvantage of the known fuel means is the complex composition, the introduction of additional components, the inability to utilize millet production waste.

Closest to the claimed technical essence and the achieved result, selected as a prototype, is a method for producing fuel briquettes from organic fiber material, mainly from wood waste (AS USSR No. 1047393, class C10L 5/44, publ. 07.10. 83 g.). The method includes grinding the organic material to a particle size of not more than 85% of the minimum size of the resulting briquettes, drying and pressing the dried material into briquettes. Before pressing in the crushed material, the moisture content is maintained at 16-28%, pressing is carried out at a pressure providing heating of the resulting briquettes to 163-177 ° C, and the resulting briquettes are dried to a moisture content of 7-8%. The description of the invention provides data on obtaining the proposed method of fuel pellets with a thickness or length of approximately 3.2-12.7 mm

The disadvantage of this method is that it is not applicable for processing waste containing a small amount of organic compounds that contribute to the formation of stable durable granules, such as waste from millet production.

The objective of the claimed invention is to create a technology for processing waste from the production of millet into solid fuel.

The technical result from the use of the invention is to expand the range of solid fuel heat sources, utilize millet production waste and improve the environment.

The specified result is achieved by the fact that in the method of producing fuel granules from organic fibrous material, including grinding organic fibrous material, moistening, heating and pressing the obtained material, millet production waste is used as organic fibrous material, and grinding of organic fibrous material is carried out to 0.25- 0.15 mm, humidification and heating are combined and carried out by treatment with steam heated to 130-180 ° C and under pressure from 4 to 5 atm, and pressing the resulting mother la is carried out in the matrixes with the diameter ratio and the length of the channel 7: 78-80. Millet husk is a waste of millet production.

Millet husk is used as a filler in the manufacture of chipboards, and husk is also used as fuel for burning in industrial boilers. But the volume of consumption in particleboard is very low, and the use of husks as fuel can only be local in nature, since the volume is large, the bulk density is small, therefore, transporting it somewhere is expensive and inexpedient. It is for logistics that husks are turned into pellets.

The method is as follows. Millet production wastes are crushed to 0.25-0.15 mm on a roller mill. The crushed raw material enters the auger mixer, in which it is mixed with superheated steam, due to which the raw material is moistened and heated. Then the raw material is fed to a granulator press, in which it passes through the matrix under high pressure and, as a result, a granule is formed. The ratio of the diameter of the holes of the matrix to their length is 7: 78-80, with this ratio the most successful formation of granules occurs, the ratio is selected experimentally.

Granules are obtained, respectively, with a diameter of 7 mm and a length of 5 to 15 mm.

The following examples illustrate the invention.

Example 1

Raw materials (millet husk) with an initial moisture content of 8-12% and a fractionality of up to 2 mm are fed to a BZN roller mill. The crushed raw material up to 0.25-0.15 mm enters the screw mixer, in which humidification and heating are carried out by treatment with steam heated to 130 ° C and under pressure from 4 to 5 atm, and then the resulting material is pressed in a press granulator OGM-1.5 (LITHUANIA) in matrices with a ratio of the diameter and length of the channel 7: 78-80.

The finished product has the form of granules (cylindrical columns) with dimensions: diameter from 7 mm to a length of 5 to 15 mm.

The obtained granules had the following characteristics:

Humidity - 8.86% iso 589-81 din 52183

Density - 685 g / l

Calorific value - 4515 kcal / kg iso 1928-95 din 51900

Ash content - 8.41% iso 1171 din 51719.

All parameters were determined in Incolab services Russia s.c. (test certificate attached).

Examples 2

Raw materials (millet husk) with an initial moisture content of 8-12% and a fractionality of up to 2 mm are fed to a BZN roller mill. The crushed raw material up to 0.25-0.15 mm enters the screw mixer, in which humidification and heating are carried out by treatment with steam heated to 180 ° C and under a pressure of 4 to 5 atm, and then the resulting material is pressed in an OGM press granulator -1.5 (LITHUANIA) in matrices with a ratio of the diameter and length of the channel 7: 78-80.

The finished product has the form of granules (cylindrical columns) with dimensions: diameter from 7 mm to a length of 5 to 15 mm.

The obtained granules had the following characteristics:

Humidity - 8.86% iso 589-81 din 52183

Density - 685 g / l

Calorific value - 4515 kcal / kg iso 1928-95 din 51900

Ash content - 8.41% iso 1171 din 51719.

All parameters were determined in Incolab services Russia s.c. (test certificate attached.)

When grinding millet husk less than 0.15 mm, high grinding costs are required due to increased electricity consumption, the need for additional processing equipment, and when grinding millet husk more than 0.25 mm, the granules are unstable, easily broken, crumble, and therefore not suitable to transportation.

When processing with steam heated below 130 ° С, the granulation process is not observed - the feedstock passes through the matrices freely without changing its shape, but at a temperature of more than 180 ° С the energy consumption increases, additional processing equipment is needed, the cost of production of granules grows, and working conditions worsen.

At a pressure of less than 4 atm, no granulation process is observed, since the feedstock passes through the matrix freely without changing its shape, and at a pressure of more than 5 atm, energy consumption increases, additional processing equipment is needed, and the cost of production of granules increases.

The ratio of the diameter and length of the channel was chosen 7: 78-80, since with a smaller ratio the productivity of the equipment decreases, which leads to an increase in the cost of production, accelerated wear of expensive technological equipment occurs, and with a larger ratio of the diameter and length of the channel, there is no granulation process at all or the granule is obtained unstable, fragile.

Thus, the proposed method allows to obtain fuel pellets from millet husk, which is a waste of millet production. The resulting fuel meets the requirements for fuel, and at the same time is cheap, environmentally friendly. Using the proposed method also solves the problem of recycling millet production waste.

Claims (2)

1. A method of producing fuel granules from organic fibrous material, including grinding organic fibrous material, moistening, heating and pressing the obtained material, characterized in that millet production waste is used as organic fibrous material, organic material is ground to 0.25-0, 15 mm, humidification and heating are combined and carried out by treatment with steam heated to 130-180 ° C and under pressure from 4 to 5 atm, and the obtained material is pressed in matrices with the corresponding Ocean diameter and length of the channel 7: 78-80. 2. The method of producing fuel granules from organic fibrous material according to claim 1, characterized in that millet husk is used as a waste of millet production.