RU2314335C2 - Method of production of the granulated solid fuel and the installation for the method realization - Google Patents

Abstract

FIELD: coal industry; municipal services; other industries; methods and devices for production of the grained solid fuel.

SUBSTANCE: the invention is pertaining to the process of production of the grained composite fuel, which is intended for usage in the communal heating supply systems or in the household purposes. The method of production of the grained solid fuel with the help of the installation includes grinding of the coal fines, introduction in the composition of the fuel of the ground vegetable additive (for example, the sawdust or the beet press), their joint grinding in the rotary roller mill, sending of the part of the produced mixture in the volume near to 1/3 to mixing with the binder and formation of the seed grains in the turbo-blade mixer. Further route the received mass of seed grains and the remaining part of the mixture in the volume near 2/3 from the mixer for granulation into the plate granulator. The binding is also routed in the granulator to form the seed grains. The produced granules of the spherical shape in the narrow range of the dimensions within 15-30 mm are dried and cooled in the sectional dryer and packed by means of the weighing-and-filling machine into the tare having the form of the cardboard boxes of the different dimensions intended for usage in the capacity of artificial fuel wood. The technical result of the invention consists in the reduced power input for the production process, simplification of the production process, improvement of ecology, the increased efficiency of production of the final product.

EFFECT: the invention ensures the reduced power input for the production process, simplification of the production process, improvement of ecology, the increased efficiency of production of the final product.

5 cl, 1 tbl, 1 dwg, 8 ex

Description

The invention relates to the production technology of granular composite fuel, which can be used for communal and domestic purposes.

It is known to manufacture carbon-containing fuel - a fuel briquette, which involves grinding raw materials including peat, brown coal, anthracite, coke, wood waste and, as a binder, a sulfonic acid derivative, sodium or potassium humate, paraffin and water glass. The briquette is molded in a paper shell (RF patent No. 2094449, C10L 5/02, 5/10, publ. 10/27/1997). Such a briquette does not have a high calorific value and, therefore, low fuel efficiency.

Closest to the proposed is a method for producing granular solid fuel (RF patent No. 2103328, С10L 5/04, 5/20, 5/00, publ. 01/27/1998), including grinding raw materials - small classes of brown coal, stone, anthracite or their mixtures, drying and heat treatment of coal at 450-600 ° C in a vortex chamber at a heating rate of 10000-15000 deg / min, grinding of coal in a disintegrator and subsequent granulation on a plate granulator in the presence of a binder - lignosulfonate. Finished granules are sent for packaging, and the resulting small fractions are screened out and returned to the process.

The main disadvantages of this method are the high energy intensity of the process at the stage of heat treatment, the use of mainly high-grade coal, as well as the formation of waste in the form of fine fractions. This increases the cost of the method and worsens the working conditions.

Thus, the objectives of the proposed method are to reduce the energy intensity of the production of granules by eliminating the stage of heat treatment, the use of low-grade coal, obtaining the finished product with virtually no separation of fine fractions.

The problem is solved due to the fact that when obtaining granular solid fuel by grinding raw materials - coal fines, granulating in the presence of a binder and drying, it is also proposed to use an additive of crushed plant material as raw materials, after grinding coal fines to particle sizes less than 3 mm, mix joint grinding of coal and plant material in the ratio (wt.%) 75-95: 25-5, respectively, to the particle size of the mixture less than 0.2 mm, part of the mixture in a volume of about 1 / 3 mix with a binder until a mass of germ grains of 3-5 mm in size is formed, and the remaining part of the mixture in a volume of about 2/3 and the formed mass of germ grains are simultaneously directed to granulation, and the same binder is used for the formation of germ grains and granulation.

Wherein

- as plant material, wood sawdust or beet pulp, or finely chopped straw, or pulp of waste from the production of ethyl alcohol is used;

- as a binder, a liquid of plant origin is used - molasses, or sulphite-alcohol stillage - waste from alcohol production, or finely ground slaked lime solution;

- for the formation of germ grains, the binder is fed into the mixture in an amount of 1-10% by weight of the supplied mixture, and for granulation, the binder is fed in an amount of 1-10% of the mass of the mixture sent for granulation.

The use of a mixture of the same composition for the formation of germ grains and for granulation, as well as the same binder, and the preparation of germ grains in the process of preparing the constituents of the mixture immediately before being fed into the granulator makes it possible to obtain granules of a homogeneous structure, high strength and high ability to ignite . Finished granules are obtained in a narrow range of fractions and with virtually no waste. The specified parameters of the method also contribute to improving the quality of the granules. The use of plant waste increases the flammability of the granules, and the use of molasses increases their strength.

Various devices for producing granular products are known, including carbon containing.

A known installation for producing a carbon-containing product (German patent No. 2421306, B01J 2/14, publ. 11/14/1974). The installation contains containers for coal powder, for additives and for water, from which metered supply of materials to the mixer and mixing in the presence of water are carried out. The resulting mixture from the mixer is fed into a plate granulator, which at the same time from special. coal particles serving as the germinal mass are fed into the container. Additional humidification is also supplied to the granulator from a separate container.

After granulation, the carbon-containing product is obtained in the form of granules or spherical pellets.

The obtained pellets have insufficient mechanical strength, as a result of which product losses during transportation and storage are possible.

Closest to the proposed is the installation described in the application of Germany No. 69613639. T2 B01J 2/00, B01J 2/14, publ. 07/04/2002.

The installation includes a container for bulk (powder) mineral materials, a screw device for grinding fibrous organic materials (wood, paper, cotton), while the tank and screw device are connected to a mixer for mixing mineral and fibrous material. Binders and additives from a series of containers are also sent to the mixer. The mixer through a container and a conveyor is connected to a disk granulator, near which there is also a series of containers for feeding a binder into it. The obtained granules in wet form are sent to a sieve system for selection of granules of the required size, which enter the drying apparatus with a cooling device, and the waste is sent to the process. After drying and cooling, the granules enter a system of vibrating screens, classifying them and directing each class into a separate container, from which the granules are packed into classes in separate containers (bags or bags). This installation is intended for the manufacture of granular products for various purposes.

The main disadvantage of this installation is the technological complexity and multi-stage production of granular finished product, the duration of the process in time and the need for high maintenance costs. And also, during certain stages, dust is emitted, especially at the stage of preparation for granulation using dry binders and at the packaging stage.

The objective of the proposed installation is the technological simplification and increase the efficiency of obtaining granulation of the finished product, as well as improving environmental friendliness and increasing the efficiency of the installation.

The problem is solved in that in the installation for producing granular solid fuel, including a container for raw materials - coal fines and a container for additives - plant material, both connected to a common mixer, as well as a plate granulator connected to a container for a binder, a drying device and a filling device , it is proposed to introduce a device for preliminary grinding of raw materials in the form of a rotary crusher between the container for raw materials - coal fines and the mixer, to introduce the device between the mixer and the plate granulator In order to form germ grains in the form of a turbopaste mixer, also connected to a binder container, the mixer should also be connected to a plate granulator, which is in communication with a drying device in the form of a sectional dryer with a coolant recirculation system in communication with a filling device in the form of a filling machine.

The proposed hardware solution of the installation can significantly simplify it and reduce the staged process of obtaining granules. Introduction to the installation of a device for the formation of germinal grains and the organization of the flow of the mixture, the germinal mass and the binder can reduce the stage and at the same time significantly improve the quality of the granules - their strength and uniformity of size.

Due to the use of highly efficient devices with low energy consumption in the installation, the costs of the entire production cycle of granular fuel are significantly reduced. The rotary crusher provides uniform grinding of coal fines to a particle size of about 3 mm. The rotor-roller mill used as a mixer performs fine grinding of dissimilar materials due to internal recirculation of the particles of the mixture and ensures the production of particles smaller than 0.2 mm. The turbopaste mixer used to obtain the germinal mass provides nuclei in a narrow range of fractions of 3-5 mm, which serves as the basis for the production of finished granules also in a given narrow range of sizes, i.e. improves the quality of the finished product.

The sectional design of the drying device maintains a predetermined temperature in each section of the device. The coolant recirculation system reduces energy consumption. The filling machine produces finished goods of high consumer properties, convenient for use for various purposes, as well as warehousing and storage. The cardboard casing also serves as a means for easily kindling fuel artificial logs.

The installation device is illustrated by the attached drawing, in which the installation diagram contains a container 1 for raw materials - coal fines, equipped with a dispenser 2, feeding coal fines into the rotor crusher 3, from which the crushed coal is fed into the mixer - rotary-roller mill 4. From the tank 5 for additives - plant material - the additive through the dispenser 6 is fed into the mixer 4, equipped with a drive (in the diagram without positions), from which part of the mixture in a volume of 1/3 is supplied to the device for the formation of the mass of germ grains Itel 7, which also contains a binder from a tank 8 through a dispenser 9. The remaining part of the mixture in a volume of 2/3 from a mixer 4 is fed into a disk granulator 10, into which a germinal mass from a turbopaste mixer 7 and a binder from a tank 8 are simultaneously fed through a dispenser 9 The finished granules from the granulator 10 are sent to a drying device - sectional dryer 11, from which the finished product is sent to a filling machine 12, packing the granules in a container 13 in the form of parallelepipeds - cardboard boxes or in the form of bags of the required capacity.

The method using the installation is as follows. The main energy component of the composite fuel is coal fines with a particle size of less than 50 mm, placed in the tank 1 in the form of a hopper. From the container 1 by the dispenser 2, coal fines are fed into the rotary crusher 3 for preliminary grinding to a particle size of less than 3 mm. Next, the crushed coal is fed into a mixer - a rotary-roller mill 4, into which crushed plant material, for example wood sawdust (or beet pulp, or finely ground straw, or pulp of waste from the production of ethanol) is fed from a tank 5 in the form of a hopper through a batcher 6 mixed and crushed in a mill 4 to particle sizes less than 0.2 mm The ratio of coal and plant parts in the mixture is (wt.%) 75-95: 25-5, respectively. The mixture accumulates in the mixer tank 4.

A part of the prepared mixture in a volume of about 1/3 of the accumulator is sent to the formation of germ grains in a turbopaste mixer 7, into which for this purpose a binder, for example molasses, is fed from the container 8 through the dispenser 9 in an amount of 1-10% of the weight of the mixture fed to the mixture . When processing the mixture in a turbopaste mixer, a mass of germ grains of 3-5 mm in size is formed for the subsequent formation of granules. The germinal mass is fed into a disk-shaped granulator 10, into which at the same time the rest of the mixture is fed in a volume of about 2/3 from the accumulator of the mixer 4. The ratio of the flows from the mixer 4 to the turbopaste mixer 7 and directly to the granulator 10 can vary from 1/3 to 1/4 . At the same time, the same binder (molasses, or sulphite-alcohol stillage - a waste of alcohol production, or a solution of slaked finely ground lime), which is supplied to form germ grains, is supplied from granulator 10 from container 8 through dispenser 9. The binder is also fed to the granulator in an amount of 1-10% by weight of the mixture sent to granulation.

Granulation is carried out by rolling on a dish-shaped granulator 10 at a plate angle of 45-75 degrees and a rotation speed of 30-90 rpm. The granulation process takes 20-30 minutes. The granulation process control system is automatic with granule size regulation by dosing of raw materials and binder, tilt angle and plate rotation speed. Ready-made wet granules of spherical shape with a diameter of 15-30 mm through a tray by gravity are released into the drying device 11 in the form of a sectional dryer with a coolant recirculation system. The granules are dried at a temperature of 120-250 ° C for 5-25 minutes, classified and cooled in the last section of the dryer. The cooled granules are fed into the filling device 12 in the form of a filling machine, which packs the finished fuel into a container 13 in the form of a parallelepiped in the form of corrugated cardboard boxes intended for use as artificial logs. The sizes of the boxes can be different depending on the purpose of the fuel and the requirements of customers, for example 10 × 10 × 30 cm, 15 × 15 × 30 cm, 15 × 15 × 40 cm, etc.

The obtained granular fuel in the form of artificial logs can be used for communal boilers, domestic stoves, fireplaces, for use in suburban, as well as in extreme conditions, etc.

The filling machine can also pack the finished product into containers of various capacities.

An example of obtaining granules.

To obtain 5 tons per hour of granules, 4200 kg per hour of coal fines of grade T coal is fed from the hopper to a rotary crusher, where it is crushed to 3 mm. Then, the crushed coal is fed to a rotor-roller mill. 750 kg per hour of wood sawdust is fed there. The mixture is crushed to a particle size of less than 0.2 mm and accumulates in the drive. From a drive of 3500 kg per hour, the mixture is fed by a spiral conveyor to a plate granulator with a diameter of 3 m. There, 70 kg per hour of a binder is supplied in the form of an aqueous solution containing 35 kg of molasses. Also from the drive 1500 kg per hour of the mixture is fed into a turbo-mixer, where 30 kg per hour of the binder is supplied in the form of an aqueous solution containing 15 kg of molasses. From the turbopost mixer, the resulting croup in the form of grains with a diameter of 3 mm is fed into the granulator. Examples of the proportions of the components in the mixture are given in the table. Finished granules with a diameter of about 30 mm exit the granulator to a receiving tray, from where they are fed with a vertical elevator into a vertical dryer for drying at a temperature of 120 ° C for 15 minutes. The dried granules from the dryer are discharged into the tray of the spiral conveyor feeding the granules into the hopper of the metering device of the filling machine. The dosing device dispenses 700 kg of granules in big bags. With appropriate settings, the dispenser dispenses 50 kg portions to paper kraft bags. The mass of granules can vary up to 5 kg, with packaging in small paper kraft bags. With the appropriate setting of the dosing device, portions of 5 kg granules are packed in cardboard boxes of 150 × 150 × 300 mm in size.

Examples of ratios of the components of the mixture.

No. The components of the mixture,% Drying Modes Coal Herbal supplement Binder Temperature, ° C Time min one 75 twenty 5 120 25 2 80 fifteen 5 180 twenty 3 85 10 5 240 fifteen four 90 5 5 180 10 5 75 24 one 250 5 6 75 fifteen 10 120 fifteen 7 94 5 one 250 10 8 85 5 10 250 twenty Note: in all examples, the finished product yield is about 100%.

Claims (5)

1. A method of producing granular solid fuel, including grinding raw materials - coal fines and granulating in the presence of a binder, characterized in that the raw material is also added an additive of crushed plant material, after grinding coal fines to particle sizes less than 3 mm, coal is mixed and co-milled and plant material in the ratio, wt.%: 75-95: 25-5, respectively, to a particle size of the mixture less than 0.2 mm, part of the mixture in a volume of about 1/3 is mixed with a binder until m the seeds are germinal grains 3-5 mm in size and at the same time the remainder of the mixture is sent to granulation in a volume of about 2/3 and the formed mass of germinal grains, while the same binder is used to form germinal grains and granulation, granulation is carried out until granules of size 15 are formed -30 mm, the obtained granules are dried at 120-250 ° C for 5-25 minutes. 2. The method according to claim 1, characterized in that as an additive to the plant material, wood sawdust or beet pulp is used. 3. The method according to claim 1, characterized in that molasses is used as a binder. 4. The method according to claim 1 or 3, characterized in that for the formation of germ grains, the binder is fed into the mixture in an amount of 1-10% by weight of the supplied mixture and for granulation, the binder is fed in an amount of 1-10% of the mass of the mixture sent to granulation . 5. Installation for implementing the method according to claims 1 to 4, including a container for raw materials - coal fines and a container for additives - plant material, both connected to a common mixer, as well as a plate granulator connected to a container for a binder, a drying device and a filling device characterized in that between the capacity for raw materials - coal fines and the mixer, made in the form of a rotor-roller mill, a device for preliminary grinding of raw materials in the form of a rotary crusher is introduced, between the mixer and the dish-shaped granulate a rum is introduced connected with them a device for the formation of germ grains in the form of a turbopaste mixer, also connected to a container for a binder, and the mixer is connected to a disk granulator, which is in communication with a drying device in the form of a sectional dryer with a coolant recirculation system in communication with the filling device in the form filling machine.