RU2185244C2 - Method of production of liquid composite fuel; disintegrator and hydraulic impact-action unit for method embodiment - Google Patents

Abstract

FIELD: technology of production of liquid composite fuels; production of water-and-carbon suspensions in particular. SUBSTANCE: method includes preliminary grinding in disintegrator having housing with inlet and outlet branch pipes, two working members in form of disks of opposite rotation on which grinding members are arranged in concentric rows; disks are directed towards each other and rows of one disk are arranged between rows of other disk. Base of inlet branch pipe found on shaft of one of disks is provided with auger to enhanced grinding of starting materials at any content of moisture. Subsequent fine grinding frequency frequently repeated during one pass is performed in hydraulic impact-action unit having housing with inlet and outlet branch, rotor of centrifugal pump on drive shaft and stator. Rotor is provided with diffusers and stator is provided with confusers; number of confusers is equal to that of diffusers; rotor and stator pair placed in individual housing forms separate section. Device has several sections connected in succession on common drive shaft and placed in common housing. EFFECT: enhanced efficiency of grinding and reduced usage of metals; reduced power requirement. 7 cl, 4 dwg

Description

 The invention relates to a technology for the manufacture of liquid composite fuel mixtures and, in particular, can be used to obtain water-coal suspensions (WCS).

 There is a method of producing a water-coal suspension from brown coal (Demidov Yu.V. et al. Pilot production of WCS from the coals of the Berezovsky section of the Kansk-Achinsk basin. - J. Coal, December, 1993, pp. 42-43), including supplying the source coal into a coarse crusher, then into a cone crusher of fine crushing, after which the coal is sent to a ball mill of the first grinding stage with water, and then the suspension is pumped into the cylinder mill of the second grinding stage. The resulting suspension through a container with a stirrer is pumped into a correction pool for storage. This method is multi-stage, metal consuming, requires high energy costs, and the resulting suspension is not of high enough quality.

 Closest to the proposed is a method for producing a water-coal suspension (patent of the Russian Federation 2138335, 02 C 19/00, publ. 09/27/99), including a dosed supply of pre-crushed to a maximum particle size of the WCS of 8 mm for mixing with water into a homogenizer, and then in the circulation tank. The resulting suspension is fed into a rotary hydropercussion apparatus, in which fine grinding is carried out by generating pulses with a frequency of resonant particle breakdown.

 The disadvantage of this method is the limited frequency of hydroshock pulses during processing in one cycle, insufficient for the preparation of highly concentrated suspensions that meet the requirements for liquid composite fuel intended for direct combustion.

 Thus, the objective of the proposed method is to increase the efficiency of hydropercussion action by repeatedly increasing the frequency of hydropercussion pulses during processing in one cycle.

 The objective is also to improve the quality of the resulting suspension due to more efficient grinding and increase the amount of its solid component.

 The problem is achieved in that in a method for producing composite fuel, comprising a metered supply of pre-ground to finely ground finely ground solid fuel components, mixing with liquid components (water with additives) and subsequent fine grinding in a liquid medium in a hydropercussion device, fine grinding is proposed water hammer treatment to be carried out repeatedly in a single pass in several sections of the hydraulic hammer device.

 In this case, the stage of preliminary grinding of solid constituent components is performed in a disintegrator.

 The main essence of the proposed method lies in the fact that with multiple cascade repetition of hydroshock impact on the processed suspension in several sections of the device, it is possible to significantly increase the grinding efficiency of its solid phase and to obtain a highly concentrated suspension with a solid component up to 55% that meets the highest requirements for liquid energy fuel intended for direct combustion. The inclusion of just one disintegrator device for dry fine grinding of raw material, which is characterized by efficiency and ease of maintenance, in the process, instead of a whole chain of equipment, can reduce the overall technological metal and energy consumption of the installation by tens of times and reduce the cost of its maintenance.

 It is known that for preliminary grinding of the original solid materials (coal, ore, rock, etc.), various devices are used.

 For example, a shock disintegrator is known (US patent 3995814, В 02 С 23/00, publ. 07.12.76), in which the raw material to be crushed is directed to a rotary reflector located in the center, and is discarded from it on an annular screen, in which Larger pieces of material that crush the target material. The output of such a disintegrator has an excessively low degree of grinding and requires further intermediate stages of grinding before serving for fine grinding, necessary for the preparation of WCS.

 Also known are crushers, ball mills and tsilpebs for grinding the starting material to a large grinding fineness (Yu. V. Demidov. Pilot production of WCS from the coals of the Berezovsky section of the Kansk-Achinsk basin. - J. Coal, December, 1993, p. 42). These devices can only be used together to achieve the desired degree of grinding.

 Known disintegrator for relatively fine grinding of dry special materials (US patent 4406409, 02 C 13/28, publ. 09/27/83), containing two rotors with opposite rotation, concentric in the rings and each carrying two rows of blades that deflect forward and back while rotating, like radial turbine blades. The rotors are mounted on hollow shafts mounted on a fixed common axis. By means of turbo action, the disintegrator produces grinding as a result of multiple collisions of particles in free flight, due to which extremely effective grinding is performed. Such a disintegrator has a complex structure, is expensive, not reliable enough, is intended only for special materials.

 Closest to the proposed one is a disintegrator for relatively fine grinding of various dry materials (AS USSR 915947, 02 C 13/22, publ. 30.03.82), containing a cylindrical body with inlet and outlet nozzles, vertically mounted in it against each other each other with the possibility of rotation in opposite directions, two working bodies with grinding elements in the form of fingers, the first working body made in the form of a disk, and the second in the form of a glass, and one concentrically covers the other. The grinding elements are arranged in concentric rows on the working bodies, and the rows of one body are located between the rows of another body, with each working body having its own drive shaft.

 The disadvantage of this device is a somewhat complicated design and insufficiently effective delivery of crushed material into the inlet pipe. Since the material has high humidity (50% and higher), which often happens in practice, it hangs in the inlet pipe and grinding does not occur at all.

 Thus, the objective of the proposed disintegrator is to simplify its design and create the possibility of grinding the starting materials of any moisture content, as well as simplifying the replacement of worn working bodies.

 To solve this problem, in a disintegrator containing a cylindrical body with inlet and outlet nozzles, two working bodies vertically mounted in it against each other with the possibility of rotation in opposite directions, the first of which is made in the form of a disk with concentric rows of grinding elements located between the rows of grinding elements of the second working body, while each working body is equipped with its own drive shaft, it is proposed that the second working body is also performed in the form of a disk with grinding elements, and in the base of the inlet pipe on the drive shaft of the first disk to install a screw.

 A feature of the device is that the disks are removable, and the cases with an end cap covering its cylinder on the whole circumference on one side, while the cover is made opening.

 The essence of this solution is that the design of the disintegrator is simplified by the implementation of both working bodies in the form of disks with concentric rows of grinding elements, from the working space of which the crushed source material is easily removed. The auger at the base of the inlet pipe helps the efficient operation of the grinding elements, which not only directs the source material into the interdisc space, but also increases the processing efficiency of wet materials (with humidity up to 0-100%), which is not possible for other devices of this class in which wet materials just get stuck in the working bodies. For the convenience of replacing worn disks, they are removable, and the end cover of the housing is made covering it on one side around the entire circumference of the cylinder and opening.

 To perform the stage of fine grinding of solid components to sizes suitable for the preparation of WCS and other types of composite fuel, hydropercussion devices are known.

 For example, a hydropercussion apparatus is known (RF patent 2138335, B 02 С 19/00, publ. 09/27/99) to obtain a fine grinding phase of a WCS, comprising a housing with inlet and outlet nozzles, an internal rotor with centrifugal pump vanes, around the perimeter of a cylindrical ring which made slit-like diffusers; an external countercurrent rotor with slit-like confusers around the perimeter of its cylindrical ring, concentrically covering the internal rotor. The number of diffusers and confusers and their difference are chosen even for the balance of hydraulic shock loads on the axis of the rotors.

 The main disadvantages of this device are, firstly, the presence of only one working chamber for performing a water hammer and, secondly, the fact that two concentrically arranged rotors have different numbers of diffusers of one and confusers of the other, as a result of which the number of complete matches and complete overlaps diffusers with confusers during the rotation of the rotors does not occur or is insufficient to create a resonant wave of water hammer and increase the effect of cavitation.

 Closest to the proposed is a rotary hydropercussion apparatus (AS USSR 1586759, 01 F 7/2, publ. 23.08.90) for producing homogeneous and heterogeneous suspensions, comprising a housing with a concentric rotor and a stator, in which the rotor is slotted diffuser holes along its perimeter, and the stator with slit-like confusers along its perimeter. The dispersion of liquid media in the apparatus is carried out by creating water hammer and cavitation slit-shaped diffusers and confusers of a special shape.

 The main disadvantage of the apparatus is the presence of only one working chamber, which does not significantly increase the force of hydraulic shock and the number of impacts.

 Thus, the objective of the proposed device is to increase the force of water hammer and create a more efficient cavitation process, which allows to achieve finer grinding and mixing of solid and liquid fuel components and to improve the quality of the resulting suspensions.

 The problem is solved due to the fact that in the hydropercussion device containing a housing with inlet and outlet nozzles, a centrifugal pump rotor on the drive shaft, made with slot-like diffusers around the perimeter of its ring, and a stator with slot-like confusers around the perimeter of its ring, the number of confusers is proposed perform the stator equal to the number of rotor diffusers, place the stator-rotor pair in a separate housing by forming a section, perform several sections in series connected by their outputs-inputs to the common m drive shaft and arranged in a general unit enclosure.

 A feature of the device is that the stator of each section is proposed to be movable.

 The peculiarity is also that the output of the last section is connected with the input of the first section by a pipeline bypass line installed between the inlet and outlet pipes of the device’s common casing, into which the control choke is integrated.

 The essence of the proposed solution lies in the fact that when the fluid passes through the rotors of all sections, it creates kinetic energy, which, as a result of periodic overlapping of the rotor diffusers and stator confusers, is converted into hydrodynamic shock energy.

When the rotor diffusers and stator confusers coincide during rotation, so-called nozzles are formed that create cavitation, which is a mechanism for converting mechanical energy (both potential and kinetic) into several types of energy: into thermal energy with heating of the medium; into the energy of hydrodynamic shock during the collapse of cavitation bubbles with the destruction and dispersion of both solid particles and particles of various liquid phases with the formation of suspensions and emulsions; into the energy of the chemical interaction of the components of the processed medium - the activation of substances. In each section of the device, the process of hydrodynamic shock and cavitation occurs m times = n • Z, where n is the number of revolutions of the drive shaft; Z is the number of diffusers in the rotor. To enhance the impact, the processes in each section are repeated n times, and due to the multiplicity of circulation of the liquid medium by the throttle along the bypass line, the required processing quality is achieved. Thus, the multi-sectional design of the device allows several times to increase the intensity of the impact, the condition for the equality of the number of diffusers and confusers makes it possible to create an impulse of movement of the processed medium with a high and steep front. This, in turn, allows you to create pulsed effects in a wide range: 1.0-100 kW / cm ² while increasing the efficiency of processing processes up to 80%. The radially movable stator provides better alignment of the rotors and stators in the package of sections.

 The invention is illustrated by drawings.

 Figure 1 shows a flow chart of a process for producing a liquid composite fuel; figure 2 is an axial section of a disintegrator; figure 3 is a side view of the device hydropercussion action with partial axial sections; figure 4 is an end section along aa device hydropercussion action.

 The technological scheme (Fig. 1) contains a unit A for dosing and supplying liquid components (water with additives), a unit B for dosing and supplying dry components of the starting materials to the unit C of the disintegrator for preliminary grinding, and then to the unit G for mixing pre-ground dry components with liquid components and the subsequent supply of the mixture to the node D of the hydropercussion device for fine grinding and final mixing of the components and obtaining the target suspension, which is fed to the node E of the storage tank, or through cr F n on the bypass line W to the node D for further processing.

 The disintegrator for dry grinding of the original solid material (for example, coal) included in the installation for implementing the method comprises a housing 1, an end cover 2, a removable disk 3 with three-row concentrically arranged grinding elements (bills), a removable disk 4 with two-row bits, a drive shaft 5 of the disk 4 and the drive shaft 6 of the disk 3, the inlet pipe 7 of the loading hopper, the discharge window 8 of the output pipe, auger 9, a removable device 10 for the cover 2, the pulley 11.

 The device of hydropercussion action (Fig. 3) for fine grinding and obtaining the target suspension contains several sections installed in a common housing, each in a separate housing 12, each section contains a rotor 13 of a centrifugal accelerator pump with slit-like diffuser openings 14, mounted on a common for all sections to the drive shaft 15, and the stator 16 with slit-like openings - confusers 17, mounted radially movably in the housing 12 of the section. In the two extreme sections from the outside on the common drive shaft, sealing devices 18 and bearing assemblies 19 are installed. Studs 20 tighten the housings 12 of all sections into a single unit, which is placed in a common heat and sound insulating housing 21. The housing 21 has an inlet pipe 22, an output a pipe 23, between which a bypass line 24 is installed with an adjustment choke 25 integrated therein.

 The technological process of obtaining fuel is as follows.

 Liquid and solid components are metered at nodes A and B. Solid components of the source material (eg coal) are fed to node B for preliminary grinding in a disintegrator. The crushed components are fed to unit G, where liquid components (for example, water and special additives) are simultaneously supplied. In node D, the components are mixed to form a coarse suspension, which is fed to node D of the hydropercussion device, in which the components of the suspension are dispersed, heated and activated until a finely dispersed suspension is formed, which is fed to storage tank E. The formation of a thin suspension of the required quality is carried out during one technological cycle, lasting a split second. If for some reason it is necessary to repeat the treatment, the suspension is recycled through the valve Ж and the bypass line З to the unit Г for repeated mixing with a corresponding reduction in the supply of primary components from the metering units.

 The peculiarity of the operation of the unit In the preliminary grinding of solid components (disintegrator) is that when dry source material enters the disintegrator (Fig. 2) through the nozzle 7, it enters the screw 9 at the base of the inlet nozzle and is pressed into the interdisc space, in which it is crushed between grinding elements (bills) of discs 3 and 4. In this case, the feed material always has some moisture, which when sticking pieces of bulk materials usually complicates the work of the disintegrator. The introduction of a screw into it allows you to load materials with humidity in the range of 0-100%. The crushed material is easily removed from the interdisc space, since there are no transverse partitions at the outlet. The maintenance of the disintegrator is facilitated by making the disks with the grinding elements removable and making the lid 2 covering the cylinder of the casing all around on one side (openable).

 The degree of processing of dry materials in the disintegrator is presented in table. 1.

 The operation of the node D - devices hydropercussion is as follows.

 The suspension of the primary processing from the mixer G is fed into the inlet pipe 22 and then sequentially to all sections through the rotors 13 of the centrifugal pumps and the radially movable stators 16. The rotors 13 - accelerator pumps, when rotated on the drive shaft 15, give kinetic energy passing through them, which due to the periodic overlap of the diffusers 14 of the rotors by the walls of the stators 16 is converted into the energy of hydrodynamic shock. When combining diffusers 14 rotors and confusers 17 stators and opening the diffuser-confuser system, a temporary structure is formed, called a nozzle, which creates cavitation in the processed liquid medium, producing a fine dispersion, heating, activation and mixing of all components of the suspension, which in one cascade passage through All sections achieve high quality. If for individual applications it is necessary to increase the fineness of dispersion, it is possible to increase the multiplicity of circulation of the medium to be processed in all sections, which is carried out through the adjustment choke 25 along the bypass line 24. In this case, the required processing quality is achieved. The resulting suspension or emulsion is discharged through the pipe 23. To reduce heat loss and noise, the overall housing of the device is made with an insulating layer. The resulting suspension can be sent both for direct use and stored in a tank. The degree of processing achieved in this device is shown in table. 2.

 Table 1 presents the results of dry grinding on a coal disintegrator of the Chernigov deposit with an initial particle size of 10 - 0 mm with a moisture content of 16% (sample 1) and 8% (sample 2), as well as silicate blocks with a particle size of 15 - 3 mm.

 In the table. 2 shows the results of wet processing of the above coal samples in an aqueous-solar medium to obtain a coal-water-solar fuel (VUST) and in water to produce a water-coal fuel (VUT), as well as a sample 2, crushed directly in a hydraulic impact device (UGD) without preliminary grinding in the disintegrator. In this case, composite fuel in both cases contained coal as a solid phase up to 55%.

Claims (7)

 1. A method of producing a liquid composite fuel, comprising a metered supply of pre-crushed to a fine fineness grinding of solid constituent components for mixing with liquid components and subsequent fine grinding in a liquid medium in a hydropercussion device, characterized in that fine grinding is carried out repeatedly in a single pass in several sections of the hydropercussion device.  2. The method according to p. 1, characterized in that the preliminary grinding of the solid components is carried out in a disintegrator.  3. A disintegrator comprising a cylindrical body with inlet and outlet nozzles and two working bodies vertically mounted in it against each other with the possibility of rotation in opposite directions, the first of which is made in the form of a disk with concentric rows of grinding elements located between the rows of grinding elements of the second working body, with each working body equipped with its own drive shaft, characterized in that the second working body is also made in the form of a disk with grinding elements, and in Hovhan inlet on the drive shaft of the first drive screw is mounted.  4. The disintegrator according to claim 3, characterized in that both disks are removable, and the case is equipped with an end cover that covers its cylinder on the whole circumference on one side, while the cover is made opening.  5. A hydropercussion device, comprising a housing with inlet and outlet nozzles, a centrifugal pump rotor on the drive shaft, made with slit-like diffusers around the perimeter of its ring, and a stator with slit-like confusers around the perimeter of its ring, characterized in that the number of stator confusers is equal to the number of diffusers the rotor, the rotor-stator pair is placed in a separate housing by forming a section, the device contains several sections connected in series with their outputs-inputs on a common shaft and placed in a common housing oystva.  6. The device according to p. 5, characterized in that the stator of each section is movable.  7. The device according to p. 5, characterized in that the output of the last section is connected to the input of the first section by a pipeline bypass line installed between the inlet and outlet pipes of the device’s common casing, into which an adjustment choke is integrated.

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