RU2653513C1 - High-energy fuel briquets from composite material based on remains of wooden materials (options) - Google Patents

Abstract

FIELD: fuel.

SUBSTANCE: invention discloses fuel briquettes from a two-component mixture of wood origin: the first component is milled remains of wooden material from wood processing enterprises and / or wood conversion enterprises, and the second component is charcoal, wherein two-component mixture is presented as homogenized composite material obtained by compounding counterdie from milled remains of wooden material and reinforcing of dispersed charcoal particles in two steps: the first stage – with combination of following simulranious processes: drying of remains of wooden material with initial natural humidity, dispersion of initial charcoal and adsorption of dispersed charcoal by counterdie; and the second step is in process of briquetting composite material, preferably by extrusion, combination of drying, dispersing and adsorption is carried out in dynamic ring-bark heat flow of mixture of flue gases with moisture vapor released during drying of remains of wooden material, while content of charcoal in source raw material is maintained within 5÷30 % by weight. Also disclosed are fuel briquettes which, after compression, are pyrolyzed.

EFFECT: technical result consists in obtaining briquettes that have increased heat output, strength and high content of non-volatile carbon.

10 cl, 2 tbl

Description

The present invention relates to the production of briquetted solid fuel based on substances of non-mineral origin, namely: products of logging enterprises and / or wood processing enterprises. The proposed fuel briquettes can be used in domestic conditions for autonomous, environmentally friendly and economical heating of premises, as well as for cooking on barbecue, grills and barbecue without compromising the organoleptic properties of food.

In the metallurgical industry, the proposed wood briquettes are an excellent alternative to the traditional reducing agent - coke (coke ash -10 ÷ 15%; sulfur content in coke - 0.5 ÷ 1.8%). So for the steel industry it is known that the highest quality cast iron is smelted on charcoal.

Also, the proposed briquettes are of interest for all sectors of human activity where an effective low-ash reducing agent with a practical lack of sulfur or an environmentally friendly carbon adsorbent is required.

At present, wood pellets are produced in significant volumes at a large number of enterprises, especially in Europe and North America. There are many technologies for the production of fuel briquettes of various compositions based on forest waste.

To date, a number of authors propose briquetting wood waste using various binders, that is, the use of binders in the molding of fuel briquettes is still relevant.

So, according to the patent RU No. 2187542 “Fuel briquette (options)” (priority date - 04.25.2001; C10L 5/10), the fuel briquette includes as a binder starch, or wheat flour, or dextrin in an amount of 3 ÷ 45 wt. %, and as a filler: according to the first option - chopped charcoal (50 ÷ 93 wt.%), and according to the second - chopped charcoal (35 ÷ 91 wt.%) and sawdust (4 ÷ 15 wt.%).

Nevertheless, the main modern trend in the development of technologies for briquetting lignin-containing raw materials is the rejection of introducing additional binder components into the briquettes.

Known patent RU No. 2369631 "Method for producing fuel pellets" (priority date - 16.06.2005; convention priority - 08.07.2004, No. 20043071; C10L 5/44; patent holder - ARBAFLEYM TECHNOLOGY AC (NO), Cambia AC (NO). According biological material, preferably wood sawdust, is fed to the drying stage and dried to a relative humidity of 40–65 wt.% to 30–45 wt.%; then, possibly through an intermediate storage stage, to the reactor stage and the material is processed under elevated pressure and heating to 200 ÷ 300 by supplying steam. the reactor to soften and reduce the pressure in the reactor in at least two stages: in the first, for separating the material into fibers and separating lignin, and in the second, for transporting the material from the reactor stage to an additional drying stage, possibly through an intermediate storage stage, and the material is granulated. When the pressure in the reactor is reduced, a part of the lignin is released in the first stage, and this lignin acts as a binding agent in subsequent granulation.

Also known patent RU No. 2518068 "Method for the production of granules or briquettes" (priority date - 05.10.2009; convention priority - 12.15.2008, No.20085249, 02.06.2009, No.20092136; C10L 5/44; patent holder - ZILHA BYOMASS FYUELZ AI Electric (US) According to this patent, a lignin-containing material with a moisture content of less than 30 wt.% Is fed into the reactor, heated to a temperature of 180–235 ° C by injection of steam into the reactor for 1–12 minutes, the pressure is reduced, and the processed material is formed to form granules or briquettes. In the method, the decompression of the reactor is carried out in two ways: the first - sharply reducing the pressure for steam explosion, and the second -. a gradual decrease in pressure without steam explosion lignin-containing material according to the processing method provides a natural binding quality which greatly exceeds the binding characteristics of the wood during mechanical pressing without prior steam treatment.

The common goal of technical solutions for obtaining wood fuel briquettes according to the above patents is the desire to improve the environmental friendliness of briquettes through the use of natural binders extracted from wood.

Common disadvantages of the above technical solutions is the high energy intensity and laboriousness in the production of the final product, which increases the cost of fuel briquettes, reducing competitiveness in conditions of market saturation.

The closest technical solution chosen for the prototype is the technical solution according to patent RU No. 2185420 "Method for producing fuel briquettes and a plant for pressing them" (C10L 5/44, priority - 03/29/2001, expiration date of the patent - 03/30/2006). The method includes grinding, drying, mixing the components of the mixture and subsequent pressing, and the wood waste is initially crushed to fractions no larger than 30 mm, then dried to a moisture content of 18 ÷ 20%, after which charcoal is produced from part of the resulting mass, and another part is crushed into chips 1 ÷ 8 mm long. The resulting chips are dried to a moisture content of 3 ÷ 7%, heating it to 180 ÷ 210 ° C without oxygen. The dried and heated chips are mixed with charcoal, the resulting mixture is subjected to preliminary compression, and then briquettes with a density of 1150 ÷ 1400 kg / m ³ , on which a protective coating is pressed, are pressed from the compressed mixture.

According to the prototype, fuel briquettes of the following composition are made:

- wood waste - 70 ÷ 95 wt. %;

- the rest is charcoal.

It is known that charcoal without a binder is not briquetted with wood waste (we will conditionally call sawdust) if the wood raw material is used without preliminary preparation. To enable briquetting without a binder in the prototype provides the following:

1. Wood briquette with a moisture content of 3 ÷ 7% is sent for briquetting after heat treatment at a temperature of 180 ÷ 210 ° C without oxygen;

2. dried to a moisture content of 3 ÷ 7% and heated sawdust with a mechanical agitator mixed with charcoal in the form of powder and / or granules with a size of 1 ÷ 3 mm in a drying and mixing plant at a temperature of 310 ÷ 320 ° C;

3. The briquetting of the raw material mixture is carried out in stages, gradually raising the pressing pressure:

- 1st stage - pre-mixing screw, where the initial mixture from the drying-mixing plant with an initial density of 120 ÷ 150 kg / m ^{3 is} compacted to 300 ÷ 400 kg / m ³ at 190 ÷ 210 ° C;

- 2nd stage - the power screw of the extruder, where the mixture is compressed to a density of 800 ÷ 850 kg / m ³ at a pressure of 60 MPa at 180 ÷ 210 ° C. The process of extrusion pressing the mixture is preliminary (preparatory) in nature;

- 3rd stage - final pressing by hydraulic press in working piston cylinders, where the mixture is compressed to a pressure of 140 ÷ 200 MPa to 1150 ÷ 1400 kg / m ³ at 190 ÷ 250 ° C.

It is necessary to note some incorrectness of the claims presented in the prototype in paragraph 2, where the interval of the ratio of the components is declared, namely: shavings - 70 ÷ 95%, the rest is charcoal. The incorrectness is due to the fact that the description clearly states that the content of charcoal depends on its state of aggregation: up to 10% by volume in the form of powder and up to 30% by volume in the form of granules.

To obtain fuel briquettes according to the prototype, a complex energy-consuming production line is provided, which includes repeating technological processes, namely: stage-by-stage briquetting of the raw material mixture (the steps are indicated above), stage-by-stage grinding (chipping machine - up to 100 mm, hammer crusher - up to 30 mm, rotary knife mill - up to 1 ÷ 8 mm) and stage-by-stage drying (to a moisture content of 18-20%), then up to 3-7%) of sawdust. All this significantly increases the capital costs of their production, as well as labor and energy costs.

Also a significant disadvantage of the briquettes according to the above patent is their geometric shape, due to the method of final pressing in hydraulic cylinders, that is, the shape of a solid cylinder. In the process of pyrolysis of such briquettes, problems arise in ensuring the uniformity of pyrolysis in the briquette body, and the mechanical strength of such briquettes also decreases due to the growth of stresses in their central part. Burning fuel briquettes of this form is less efficient and unsafe.

The technical task of the invention is the production of environmentally friendly fuel briquettes recommended for use in everyday life, including for cooking. Moreover, the technology of their manufacture should significantly reduce their cost while significantly increasing all operational characteristics. As in other areas of human activity, to ensure long-term stable demand, it is necessary to produce fuel briquettes that not only correspond to existing consumer properties, but also use only renewable plant materials without the use of fossil components in their manufacture.

The technical result obtained from the use of the invention is an ideal ecological vegetable fuel, including for cooking, since the combustion process of the proposed briquettes provides an efficient energy transfer with the necessary and sufficient period of temperature development for cooking food.

The offered briquettes meet the highest consumer properties:

- environmental friendliness;

- high density while maintaining the capillary structure;

- high hydrophobicity, which is very important in conditions of high humidity, for example, in Japan, environmental humidity practically does not decrease below 60%;

- even burning with a constant flame intensity throughout the entire burning period;

- ease of ignition;

- low smoke emission;

- low formation of fly ash;

- high safety at work;

- preservation of the organoleptic properties of food products in the cooking process.

The technical result is achieved by the fact that in fuel briquettes from a two-component mixture of vegetable, preferably wood, origin: the first component is crushed wood waste from wood harvesting enterprises and / or wood processing enterprises, and the second component is charcoal, the two-component mixture is presented in the form of a homogenized composite material obtained compounding the matrix of crushed wood waste and hardening dispersed particles of charcoal, carried out two stages: the first stage - when combining the following simultaneous processes: drying waste wood with the original natural moisture, dispersing raw charcoal adsorption matrix and the dispersed charcoal; and the second stage is in the process of briquetting the composite material, preferably by extrusion, moreover, the combination of drying, dispersion and adsorption is carried out in a dynamic ring-shaped heat stream of a mixture of flue gases with wood waste vapor released during the drying process, while the content of charcoal in the feedstock is maintained in within 5 ÷ 30 wt. % In this case, the initial size of wood waste and charcoal does not exceed 5 mm; wood waste is in the form of sawdust and / or microchips, and / or shavings, and the moisture content of wood waste before briquetting does not exceed 8 wt. %, and the fuel briquettes are in the form of a prism with a central through hole.

According to the first embodiment of the manufacture of fuel briquettes, reflected in the first paragraph of the claims, the pyrolysis of briquettes is not provided. The briquettes obtained according to the first variant meet all consumer requirements both in terms of storage and transportation, and in terms of direct burning. According to the first embodiment, fuel briquettes are a full-fledged commercial product with its own consumer.

The second option of commodity fuel briquettes obtained by the proposed technical solution (paragraph 6 of the claims) is characterized by the presence of pyrolysis at the end of an identical production line. Pyrolyzed fuel briquettes acquire a number of additional positive consumer properties, for example: increased calorific value, strength, high content of non-volatile carbon.

To clarify the essence of the proposed technical solution, we give the following information.

1. For the manufacture of products of high density and strength using composite materials based on ultrafine and dispersed active powders.

Existing composite materials can be divided into three main classes, distinguished by their microstructure: dispersion-strengthened, particle-reinforced and fiber reinforced. All these materials are a matrix of some substance or alloy in which the second phase is distributed - usually more rigid than the matrix, which serves to improve one or another property. The separation of the three mentioned classes of composite materials is based on the features of their structure.

Finely dispersed powders are used as additives to obtain dispersion-hardened products, and the amount of additive is possible only to a certain limit so as not to reduce, for example, properties such as plasticity during extrusion, or activation during sintering (pyrolysis) of products.

When using dispersed powders as hardening particles, it is necessary to give the particles, their surface layers, the so-called active state, characterized by an excess supply of free energy. This state of the powder can be, firstly, the result of high macro- and microdefective particles, since dispersed powders are characterized by a certain degree of distortion of the crystal lattice, and, secondly, the result of physicochemical activation of the powder. This explains the proposal of the authors of the claimed invention - to use dispersed particles of charcoal as reinforcing particles.

The crushed wood particles are very heterogeneous and have defective structures, surface irregularities, microcracks, breaks, and the emergence of active physicochemical bonds, including hydroxyl bonds, on the surface of dislocations, which makes it possible to consider crushed wood waste as an ideal matrix for dispersed charcoal particles.

In technological processes using wood, specific effects arising in working environments under the influence of powerful heat fluxes are important (determining) significance. Among the most important effects are the physicochemical changes that occur in the wood material, both reversible and irreversible. Wood is a mixture of amorphous polymers with a developed supramolecular structure - a large number of hydrogen bonds. With simultaneous heat-steam-mechanical treatment of wood particles, the temperature of the polymer transition from the glass transition phase to the elastic and viscous flow state decreases, due to a decrease in hydrogen bonds and a decrease in the degree of polymerization of the material. The presence of a viscous-fluid (liquid) phase on the surface of wood particles ensures the strength and density of the briquette during subsequent pressing. By changing the parameters of the heat-steam-mechanical treatment of sawdust (microchips), it is possible to change the temperature of the transition of wood into a viscous flow state.

Taking into account the above information, the authors propose to combine the process of drying wood chips with flue gases with the initial natural moisture and the processes of grinding (dispersion) and adsorption of charcoal. At the exit from the drying, a composite material is obtained, characterized by maximum preparation for extrusion pressing and further pyrolysis to obtain strong and dense briquettes with increased calorific value.

To obtain durable briquettes, it is necessary that the material in the pressing chamber be in a viscous-fluid (liquid) state, which is ensured, firstly, by the temperature regime (not lower than 170 ° C), and secondly, by the optimum humidity of the pressed raw material. By selecting the optimum moisture content of the raw material mixture going to pressing, it is possible to achieve a change (optimization) in the temperature of transition of wood to a viscous flow state in each case. The need to vary the moisture content of the raw materials before pressing is caused by the fact that the content of dispersed reinforcing charcoal particles in the composite material, which generally increase the viscosity of the pressed mixture, varies within 5–30 wt. % At the same time, the presence of dispersed particles of charcoal sharply increases the vapor-gas permeability of pressed briquettes, which allows briquettes with minimal, practically stable humidity to be obtained at the output, which ensures the mechanical strength of the briquettes.

According to the existing classification of composite materials for a class hardened by particles, it is assumed that the content of hardening particles is 20–25 vol. %

In the prototype, the content in the raw mixture of charcoal in the form of powder particles is allowed only up to 10 vol.%, Which is clearly not enough for the formation of a new homogeneous structure of the briquette. In the case of using prototype up to 30 vol.% Charcoal, but in the form of granules with a size of 1 ÷ 3 mm, the formation of a composite material is generally excluded, since one of the fundamental requirements for composite materials is not satisfied: the material is homogeneous on a macro scale and heterogeneous on a micro scale.

Summarizing, we can conclude that in the structure of the briquettes of the prototype there are no qualitative changes corresponding to the formation of a new composite material that is not found in nature, but is a creation of man. In the prototype, a two-component raw material mixture is only a mechanical mixture of two constituent materials.

In the proposed technical solution, the original completely new technology for the preparation of a two-component raw material mixture in a dynamic ring-shaped powerful steam-gas-heat flow allows one to obtain a new composite material for briquetting, which is visually (on a macro scale) perceived as a structurally homogeneous material. Moreover, the claimed interval of the content of reinforcing dispersed particles of charcoal within 5 ÷ 30 wt. %, taking into account the bulk density of dispersed charcoal (0.26 ÷ 0.45 g / cm ³ ), significantly exceeds the known limits (20 ÷ 25 vol.%) recommended by the existing practice of creating particle-hardened composite materials.

A significant increase in the content of reinforcing particles in the proposed composite material leads to a five-fold increase in the strength of briquettes (both pyrolyzed and non-pyrolyzed) compared to briquettes from a matrix material without reinforcing particles obtained by identical technology. In this case, the density of the products increased to 1.3 g / cm ³ .

The high strength properties of briquettes from the proposed composite material are to some extent related to the high affinity of the matrix material (sawdust) and the material of reinforcing dispersed particles (charcoal). Materials of similar origin (wood) give higher adhesive properties to the composite based on them. In addition, such a composite material during the combustion process behaves as a homogeneous material. The structure of extruded briquettes is a homogeneous structure that is outwardly close to plastic, and the structure that retains high porosity. After pyrolysis, the geometric shape of the extruded briquette does not change, but only the geometric parameters change, and during the pyrolysis, the porous nature of the product’s structure is manifested visually.

Thus, the totality of the proposed starting components, subjected to the original, at the level of the invention, processing in a dynamic looped powerful heat multicomponent stream, provides a material that is not found in nature and has properties different from the properties of each component taken separately, that is, obtaining a composite material.

2. As stated in the claims, a composite material is obtained by compounding a matrix of wood waste and reinforced dispersed particles of charcoal in two stages: the first by combining the drying of wood waste and dispersing and adsorbing charcoal, and the second by briquetting, preferably extrusion .

In the prototype, the first stage of mixing the components of the working mixture is carried out in the mixer by traditional mechanical mixing with agitators in the mixer at a temperature of 310 ÷ 320 ° C, and the mixture is heated to 180 ÷ 210 ° C and dried to a moisture content of 3 ÷ 7% wood sawdust and charcoal. Under such conditions, activation of charcoal is impossible, since in order to remove resinous substances formed during the dry distillation of wood and filling the pores in ordinary charcoal, first of all, a powerful stream of superheated steam is required, which is not realized with wood sawdust moisture of 3-7%. Therefore, a deep, at the pore level, especially micropores and mesopores, the interpenetration of individual components of the composite material in the prototype is not possible.

Initial sawdust is a unique material, characterized in that the individual fibers are spatially individualized, hydrated and shortened. This leads to the retention of a significant amount of water by sawdust (up to 50-60% of the total volume). This amount of moisture is sufficient for steaming both the sawdust and charcoal. Therefore, the author proposed a joint thermal preparation of the components of the composite material in a dynamic ringed powerful multicomponent heat flow, including the source flue gases and the resulting vapor-gas mixture.

Both in the prototype and in the proposed solution, in the compressed body of the briquette, the individual fragments are interconnected using lignocellulosic wood fibers acting as a binder. Lignocellulose is a mixture of three types of natural water-insoluble polymers: cellulose, hemicellulose and lignin, which are present in different proportions depending on the origin of lignocellulose. Lignocellulose has a fibrous structure. Therefore, sawdust is molded without the addition of a binder, since they themselves stick together when they are briquetted at elevated temperatures. The minimum ductility temperature of wood is 163 ° C. At temperatures above the minimum, the elastic deformations arising in the material at the briquetting pressure completely disappear and the particles come into close contact with each other. The cohesion of the interface, the mutual penetration of individual fibers, particles and the possible adhesion of heat-softened lignin (a natural binder between wood fibers) - all this causes a binding effect that gives sufficient strength after cooling after pressing.

All of the above processes of hardening the briquette, in General, are characteristic of both the prototype and the proposed briquettes. However, the adhesion of heat-softened lignin for briquettes according to the proposed technical solution has a distinctive mechanism. The binding of particles of sawdust to particles of reinforcing dispersed activated charcoal particles is carried out more firmly at the pore level.

When pressed on the surface of the briquette, a lignocellulosic rigid annular shell is formed, that is, a shell made of a natural binder, so there is no need to form an additional protective coating. The briquettes obtained in the proposed solution are practically non-hygroscopic.

3. In the process of semi-industrial testing of the production technology of the proposed briquettes, a significant increase in the performance of extrusion presses with standard electricity consumption was revealed. This is because the combined steaming of sawdust and charcoal allows you to get a softer texture of the composite material than in the material of the prototype.

4. With regard to the size of the grinding of the starting components, the authors do not put forward stringent requirements: preferably no more than 5 mm. This applies both to wood waste and charcoal, since the initial degree of grinding of charcoal is leveled to the required dispersion due to mechanical grinding (abrasion) in the process of joint high-speed movement in a powerful thermal ring flow.

The combined movement of wood waste and dispersed particles of charcoal in an intense turbulent heat flow provides a uniform distribution of reinforcing particles of coal in the volume of the wood matrix. The uniform distribution of the hardening particles allows one to obtain a composite material with an equivalent linear expansion coefficient in the volume of the briquette during the pyrolysis process, which means to preserve its integrity as much as possible, which determines a significant increase in its strength. This also substantiates the increase in the strength of even not pyrolyzed briquette.

5. The proposed geometry of the briquette allows you to:

- intensify the process of their manufacture on extruder presses;

- to ensure uniformity and equivalence of the processes of pressing (manufacturing) in the volume of the briquette;

- to ensure uniform burning in the volume of the briquette due to the presence inside the central hole of a plurality of equivalent ignition points.

The presence of an internal through hole is not only technologically necessary, but as described above increases the number of ignition points. The main combustion surface is located inside the briquette and thus occupies a sheltered position protected by the briquette itself.

A comparative analysis of the essential features of the proposed technical solutions and solutions for the prototype showed the following.

The inventive fuel briquettes have a novelty in comparison with the briquettes of the prototype, differing from them in a number of essential features: firstly, the briquettes are made from particle-hardened composite material, the matrix of which is ground wood waste, and dispersed particles of charcoal are used as hardening particles. Secondly, the proposed composite material is characterized by the greatest possible homogeneity and isotropy, which means density and strength, due to the use of two-stage compounding in the technology of its manufacture, which allows to realize and enhance the properties of each initial component with maximum benefit. The fundamental difference from the prototype, which mainly determines the positive result of the invention, lies in the first stage of compounding: combining the simultaneously proceeding processes of drying wood waste with the original natural moisture content, dispersing the initial charcoal and adsorbing the dispersed charcoal matrix. The first stage of compounding the starting components is carried out in a dynamic ring-shaped heat flow of a mixture of flue gases with the moisture vapor of wood waste released during the drying process. The resulting composite material is the result of the physico-chemical properties of the starting components that are simultaneously changing in time, occurring both in the process of their combined heat-steam-mechanical treatment in a powerful looped multicomponent dynamic heat flow, and in the process of extrusion pressing. In the claimed technical solution, the distinguishing feature of the prototype is also the geometric shape of the fuel briquettes: a prism with a central through hole.

The comparative analysis of the essential features of the proposed solution and the prototype solution indicates that the claimed solution meets the patentability criterion of "novelty."

Compliance with the current technical level follows from a patent search and a search in the subject technical literature, the results of which are given in the “analogues” description section.

As a result of a search by patent and other technical sources of information, technical solutions were not identified that are characterized by a combination of essential features similar to the proposed solution that achieve similar results when used, which allows us to conclude that the proposed technical solution meets the patentability criterion of “inventive step”.

However, some features characterizing the claimed solution are identified in currently known information sources.

1. So, the manufacture of fuel pellets from biomass, consisting of components with different lignin content, acting as a natural binder in the formation of granules, is known, for example, from Chinese patent CN 101824347 "Fuel granules from plant materials, production method and equipment for implementing the method "(C10L 5/44; priority - 03/06/2009; applicant - BEIJING FANOURUIDE TECHNOLOGY CO LTD, UNIV NANJING FORESTRY; publication - 09/08/2010). As a constituent of pressed biomass, mainly wood waste characterized by natural highly m of lignin and straw with a low lignin content. According to the method, each of the constituent biomass materials is crushed, separately dried, then mixed and subjected to steam softening. Next, the softened biomass is molded, cooled and granular fuel is packaged. The straw is dried in an oven to the state that ensures its optimal grinding in the future. Wood waste is crushed in two stages: the first - up to 10 ± 0.2 mm in a wood crusher, the second - up to 5 mm in a grinder. The crushed wood is dried in a dryer to a water content of 10 ÷ 16 wt. % The mixing of the crushed dried wood waste and dry straw is carried out in mechanical-type mixing apparatuses, where additional grinding of the raw mix takes place. Before pressing, the mixed biomass is softened with steam and granules are formed with a diameter of 6–8 mm and a length of 1–5 times the particle diameter. Press temperature 100 ± 5 ° C. After pressing, the fuel granules are cooled, sieved and then packaged

In the process of heat treatment (drying), the lignin contained in wood waste undergoes a number of physico-chemical changes that reduce its bonding ability. Therefore, separate drying of the components of the mixture results in the production of less durable granules, which is confirmed in the above patent by the need to sift the finished array of fuel granules.

2. The use of a dynamic stream of superheated water vapor in the preparation of wood waste for pressing is known from patent RU No. 2046821 “Method for the manufacture of fuel briquettes from wood waste” (C10L 5/44, patent holder - Scientific and technical and production and implementation center “TOKEMA” (BY ), priority - 08/12/1992). According to this method, steam treatment is carried out in the filtration mode, which requires a rather complicated production line with significant energy and labor costs.

3. To minimize the hardware content of technological lines for the production of wood briquettes, a number of authors propose to isolate lignin from lignin-containing materials by steam treatment at temperatures up to 250 ° C directly in the pressing equipment. This solution is protected in CA patent No. 1141376 “Method for the isolation of lignin from lignin-containing materials and products obtained by this method” (C07G 1/00, inventor - LONG EDWARD, priority 15.02.1983) and patent RU No. 2191799 “Method for lignin-containing briquetting materials and a set of tools for its implementation ”(C10F 7/06, patent holder - Open Joint-Stock Company Altai Research Institute of Engineering Technology, priority - 08/14/2000). In both solutions, the press is made with the possibility of preliminary steaming of the pressed material directly in front of the pressing chamber. Pressing equipment of this type is characterized by low productivity due to the cyclical nature of its action (cyclic steam supply).

Currently, it is not known from the available sources of information, that is, from the current state of the art, to fabricate a composite material of plant origin under the conditions of a powerful looped multicomponent dynamic heat flow consisting of flue gases, ground wood waste with natural initial moisture content, ground charcoal and steam gases released from wood waste in the process of their movement in the heat flow.

The above information regarding both the prototype and the known solutions in a similar field allows us to conclude that the claimed new combination of known and unknown features, which differs in both the technical nature of the features and their sequence and relationship, ensures the achievement of a higher result in the proposed solution in comparison with the well-known level solutions - obtaining environmentally friendly fuel briquettes with high consumer properties.

The claimed fuel briquettes in February 2017 were tested at VNIITP-TESTING CENTER LLC (St. Petersburg) in the testing laboratory of peat and its processed products. The test results are presented: in table. 1 - for non-pyrolyzed briquettes, in table. 2 - for pyrolyzed briquettes.

Industrial production of the inventive wood briquettes is as follows.

As the feedstock, wood chips and / or microchips and / or wood chips, as well as charcoal, as a rule, are substandard. The humidity of the feedstock is natural and is not adjusted before the drying oven. The size of the feedstock supplied to the drying ring furnace of the original author's design does not exceed 5 mm. Dosing of both types of feedstock is carried out by weight. The load in the drying furnace of charcoal can vary within 5 ÷ 30 wt. % Within these limits, charcoal acts as a reinforcing element of the final composite material, the matrix of which are, for example, sawdust. In the drying oven, the first stage of compounding a two-component mixture is carried out under conditions of combining simultaneously occurring processes: drying of wood waste with the original natural humidity, dispersion of the original charcoal and adsorption of the dispersed charcoal matrix. A homogenized material leaves the drying oven and is fed to the extrusion press for briquetting. The moisture content of the material before briquetting does not exceed 8 wt. % Practically humidity ranges from 5 ÷ 8 wt. % depending on the plasticizability of the material. Briquettes obtained on an extrusion press have a stable spatial prismatic shape and are the target marketable product corresponding to the first claim.

To obtain the second type of the target commercial product corresponding to the sixth claim, the briquettes after pressing are sent to the pyrolysis furnace of the original author's design.

Laboratory tests of both types of briquettes showed their significant advantage in terms of calorific value, as well as environmental indicators. The use in the production of the inventive briquettes of the original cost-effective high-performance equipment of the author's development significantly reduces the cost of production while improving its quality. The inventive fuel briquettes made of composite material are a new worthy product in the market of environmentally friendly molded fuels.

Claims (10)

1. Fuel briquettes from a two-component mixture of plant, preferably wood, origin: the first component is crushed wood waste from wood-cutting enterprises and / or wood processing enterprises, and the second component is charcoal, characterized in that the two-component mixture is presented in the form of a homogenized composite material obtained by compounding matrices of ground wood waste and reinforced dispersed particles of charcoal, carried out in two stages: the first stage - when combining the following simultaneously occurring processes: drying of wood waste with the original natural humidity, dispersion of the original charcoal and adsorption of the dispersed charcoal matrix; and the second stage is in the process of briquetting the composite material, preferably by extrusion, moreover, the combination of drying, dispersion and adsorption is carried out in a dynamic ring-shaped heat stream of a mixture of flue gases with wood waste vapor released during the drying process, while the content of charcoal in the feedstock is maintained in within 5 ÷ 30 wt. % 2. Fuel briquettes made of composite material according to claim 1, characterized in that the initial particle size of wood waste and charcoal does not exceed 5 mm. 3. Fuel briquettes from a composite material according to claim 1, characterized in that the wood waste is in the form of sawdust, and / or microchips, and / or shavings. 4. Fuel briquettes from a composite material according to claim 1, characterized in that the moisture content of wood waste before briquetting does not exceed 8 wt. % 5. Fuel briquettes from a composite material according to claim 1, characterized in that the fuel briquettes are in the form of a prism with a central through hole. 6. Fuel briquettes from a two-component mixture of vegetable, preferably wood, origin: the first component is crushed wood waste from wood-cutting enterprises and / or wood processing enterprises, and the second component is charcoal, characterized in that the two-component mixture is presented in the form of a homogenized composite material obtained by compounding matrices of ground wood waste and reinforced dispersed particles of charcoal, carried out in two stages: the first stage - when combining the following simultaneously occurring processes: drying of wood waste with the original natural humidity, dispersion of the original charcoal and adsorption of the dispersed charcoal matrix; and the second stage is in the process of briquetting the composite material, preferably by extrusion, moreover, the combination of drying, dispersion and adsorption is carried out in a dynamic ring-shaped heat stream of a mixture of flue gases with wood waste vapor released during the drying process, while the content of charcoal in the feedstock is maintained in within 5 ÷ 30 wt. %, and the briquettes are subjected to pyrolysis. 7. Fuel briquettes from a composite material according to claim 6, characterized in that the initial particle size of wood waste and charcoal does not exceed 5 mm. 8. Fuel briquettes from a composite material according to claim 6, characterized in that the wood waste is in the form of sawdust, and / or microchips, and / or shavings. 9. Fuel briquettes from a composite material according to claim 6, characterized in that the moisture content of wood waste before briquetting does not exceed 8 wt. % 10. Fuel briquettes made of composite material according to claim 6, characterized in that the fuel briquettes are in the form of a prism with a central through hole.