RU2153524C2 - Hydrolysis lignin briquettes' production line - Google Patents

Abstract

FIELD: manufacture of building materials. SUBSTANCE: invention relates to processing of fine industrial wastes, in particular vegetable material and wood hydrolysis waste and can be used in production of briquettes from crude hydrolysis lignin. Production line contains, installed in process direction and interconnected by transportation means, lignin pulp preparation unit, pulp concentration unit, drying unit, grinding unit, pressing unit, and blend preparation unit. Drying unit is provided with generator of high- frequency current electromagnetic field and with lignin blocks' transportation conveyor, by means of which pulp dehydration and lignin blocks' pressing units is connected with grinding unit. EFFECT: reduced fire and detonation risk and expanded functional possibilities. 7 cl, 4 dwg

Description

 The invention relates to the field of processing dispersed industrial wastes of wood chemistry and woodworking and can be used in the production of briquettes from technical hydrolysis lignin.

 A known hydrolysis lignin briquetting line, in which, in the course of the technological process, a heat carrier generator, a drying module of the original lignin, connected in series as transport pipelines of the hopper for the initial lignin with a screw feeder, a pneumatic dryer, and a mill mill dryers, containers for dried lignin with a screw feeder, smoke exhaust and wet scrubber, and a briquetting module in the form of a roller pre SSA (Integrated use of raw materials and waste / B. M. Ravich et al., Moscow: Chemistry, 1988, p. 45, Fig. 1-16).

 In a known line, hydrolytic lignin with an initial moisture content of 60-70% is dried in two stages to obtain a lignin mass with a moisture content of 12-18%, which is then pressed under a pressure of 70-100 MPa to obtain lignin briquettes.

 The disadvantages of the known line include the high thermal inertia of the drying module and the high fire and explosion hazard of the drying process.

 A hydrolysis lignin briquette production line is also known, including a lignin pulp preparation module, a lignin pulp enrichment module, a lignin crushing module, a pulp dehydration module, a pneumatic gas drying lignin module with a coolant generator, and a briquette module ( Development of technology and equipment for an integrated line for the production of briquettes and coke briquettes from hydrolytic lignin / Research Report, E.A. Tsyganov, All-Russian Research Institute of Hydrolysis, L., 1986, N 1P 01860050304, pp. 26-28).

 The known line is the closest to the proposed and selected as a prototype.

 In a known line, the initial lignin is dissolved in water to the ratio T: L = 1: 10. The resulting lignin pulp is neutralized with an alkali solution and then enriched by purification of foreign matter, sorting and grinding a large fraction. Next, the enriched lignin pulp is subjected to mechanical dehydration in chamber filter presses with the return of the filtrate to the pulping of the original lignin.

The lignin mass dehydrated on filter presses with a moisture content of 50-55% is disintegrated and fed to air-gas drying. Lignin is dried in a stream of a drying agent (flue gas) with a temperature of ~ 600 ^o C to a moisture content of ~ 15%. Dried lignin is supplied for briquetting. The briquettes are pressed in a roller press at a pressure of ~ 100 MPa.

 The disadvantages of the known line also include the high energy intensity and fire and explosion hazard of pneumogas drying of dispersed lignin mass.

 In addition, the known line does not provide for the possibility of mixing the dried lignin mass with additives, for example, a carbon reducing agent and silica-containing raw materials to obtain a briquetted mixture for smelting crystalline silicon.

 The objective of the invention is to reduce the fire and explosion hazard of the process and expand the functionality of the line by providing the possibility of drying the lignin mass in the form of pressed blocks by the action of the electromagnetic field of high frequency currents and lining the lignin mass before briquetting with special additives.

 The specified technical result is achieved by the fact that the production line of briquettes from hydrolytic lignin, including a lignin pulp preparation unit, a pulp enrichment unit, a pulp dehydration unit, a drying unit with a coolant generator, a crushing unit and a pressing unit, installed during the process and connected by vehicles lignin briquettes according to the invention is equipped with a charge preparation unit placed before the pressing unit briquettes and associated transportation means with a crushing unit, wherein the pulp dehydration unit is a pulp dehydration and lignin block pressing unit, on which a lignin block pressing chamber is mounted, and the drying chamber is equipped with a high frequency electromagnetic field generator and a lignin block conveying conveyor, by means of which a pulp dewatering unit and pressing lignin blocks is associated with a crushing plant.

 In a preferred embodiment of the invention, the pulp dewatering and pressing unit for lignin blocks is arranged as a lining apparatus with a filtrate collecting tank connected to the pressing chamber.

 Moreover, the lining apparatus is a hopper with a filtering conveyor, and the pressing chamber is installed on the bed of the filtering conveyor.

 In this case, the drying unit is a tunnel chamber connected by an air duct to a coolant generator in a closed loop.

 Moreover, the conveyor for transporting lignin blocks is made in the form of perforated plates of non-magnetic metal, mounted on both sides on traction chains placed on a frame installed in the tunnel chamber.

 In addition, the generator of the electromagnetic field of high-frequency currents is a high-potential electrode in the form of a perforated sheet of non-magnetic metal, connected by a waveguide to a high-frequency generator, and the electrode is mounted above the conveyor for transporting lignin blocks.

 In this case, the preparation of the mixture is at least one storage hopper with a dispenser associated with the mixer.

 The advantage of the proposed line lies in the fact that the combination of its distinctive features, due to the possibility of forming a lignin mass in the form of pressed blocks and drying them by exposure to a high-frequency electromagnetic field, allows reducing the fire and explosion hazard of briquette production by eliminating the gas-gas drying of dispersed lignin mass. In addition, the subsequent disintegration of the lignin blocks and lining of the lignin mass with ingredients to produce, in addition to fuel briquettes, briquettes for the metallurgical industry, expands the functionality of the line.

 The invention is illustrated by drawings, where in FIG. 1 schematically shows a general view of the line; in FIG. 2 shows the installation of pulp dehydration and pressing of lignin blocks; in FIG. 3 shows a drying unit; in FIG. 4 is a plan view of FIG. 3.

 The hydrolysis lignin briquette production line comprises, installed during the technological process and interconnected by vehicles, a lignin pulp preparation unit 1, a lignin pulp enrichment unit 2, a lignin block dehydration and pressing unit 3, a drying unit 4, a crushing unit 5, a charge preparation unit 6 and installation 7 for pressing fuel and / or charge lignin briquettes.

 Installation 1 for the preparation of lignin pulp is intended for pulping hydrolysis lignin and is a receiving hopper 8 with a bypass pipe 9.

 Installation 1 by a pipeline for the transportation of pulp is connected to the buffer tank 10 of installation 2.

 Installation 2 enrichment of lignin pulp is a buffer tank 10, a hydrocyclone 11 and a collecting tank 12 of the pulp, interconnected by a transport pipeline.

 The buffer tank 10 is designed to separate impurities and alkaline treatment of the pulp and is made in the form of a housing 13 with a conical bottom 14 and a cover 15 with nozzles for the input of the pulp 16 and sodium hydroxide 17. In the central part of the housing there is a mixer 18, in the lower part - outlet pipe 19 pulp, and in the bottom 14 of the body - a valve for dumping foreign matter (not shown).

 The hydrocyclone 11 is designed to separate sand and sludge and is a cylindrical body 20 with a feed 21 and a sand nozzle 22 and a drain pipe 23.

 The collection tank 12 is designed to reserve the stock of pulp and is made in the form of a housing 24 with nozzles for input 25 and output 26 of the pulp installed respectively in the upper and lower parts of the housing, a mixer 27 of the pulp located in the central part, and a valve for dumping sand and slag in the bottom of the body (not shown).

 Installation 2 by a transport pipeline is connected to the lining apparatus 28 of installation 3.

 Installation 3 of pulp dehydration and pressing of lignin blocks is intended for preliminary pulp dehydration and forming from the obtained lignin mass of blocks in the form of plates with a residual moisture content of up to ~ 45% and is a lining apparatus 28 in the form of a hopper with a leveling drum 29 and a filter conveyor 30 mounted on the bed 31, and a pressing chamber 32 mounted on the latter in the form of a vibrating table 33 with longitudinal sides 34, front 35 and rear 36 of the slide and punch 37.

 To increase the degree of dehydration of lignin blocks, a filter conveyor with a pressing chamber is connected to a vacuum chamber 38 connected by a pipeline to the tank 39 of the filtrate collector.

 The filtrate tank-collector 39 is connected by a transport pipeline to the hopper 8 of unit 1 and / or a hydrolysis line (not shown in the drawing).

 Installation 3 retractable roller table 40 is connected to the conveyor of the drying unit 4.

 The drying unit 4 is designed to dry the formed lignin blocks to a moisture content of ~ 12% by exposure to the electromagnetic field of high-frequency currents and a directed flow of coolant - air and is a tunnel chamber 41 connected by an air duct 42 to a closed circuit with a coolant generator 43. Along the axis of the chamber on the frame 44 is mounted conveyor 45 in the form of perforated plates 46 of non-magnetic metal, for example of brass, mounted on both sides of the traction chains 47, placed in the guide rails on the tension and sprocket wheels 48. The conveyor frame is grounded.

 A high-potential electrode 49 is installed above the upper branch of the conveyor to create an electromagnetic field of high-frequency currents in the form of a perforated sheet of non-magnetic metal, such as brass, mounted on insulators with height adjustment (not shown).

 The electrode 49 of the waveguide 50 is connected to a generator 51 of high frequency.

 To quench the electromagnetic waves of high-frequency currents, the chamber 41 is connected at the input and output with pre-chambers 52 mounted on the frame of the conveyor 45.

 Installation 4 by a conveyor belt 53 is associated with the installation 5 crushing of dried lignin blocks.

 Installation 5 crushing lignin blocks is designed to obtain from dried lignin blocks lignin mass with a particle size of minus 10 mm and are, for example, twin roll crusher 54 with gear rolls.

 Installation 5 by a chain elevator 55 is connected with the storage hopper 56 of the installation 6 of the preparation of the charge.

 Installation 6 of the preparation of the mixture is designed to mix the initial components of the mixture and represents at least one storage hopper 56 with a dispenser 57 and a mixer 58, for example a screw connected to a dispenser.

 Unit 6 is connected to the hopper 59 of unit 7 for pressing fuel and / or charge lignin briquettes.

 Installation 7 is intended for the manufacture of lignin briquettes - fuel and / or charge and is a high-pressure roller press 60 connected by a screw presser 61 with the hopper 59 of the charge.

 Line installations and communication vehicles have a drive with a centralized control panel (not shown).

 The line works as follows.

 The initial hydrolysis lignin with an acidity of ~ 0.72%, an ash content of 3-5%, a moisture content of ~ 65% is loaded into the receiving hopper 8 of unit 1, where it is diluted with water to the ratio W: T = 10: 1, and then connecting the hopper 8 to the bypass pipeline 9 mixes thoroughly, circulating in a closed circuit between them.

 The obtained lignin pulp is transported to the column 10 of the pulp enrichment unit 2.

 In the vessel 10, the lignin pulp entering the housing 13 through the nozzle 16 is neutralized with stirring by the stirrer 18 with a 10% sodium hydroxide solution entering through the nozzle 17, and then after separation by density from foreign matter through the nozzle 19 it is fed to the cyclone 11 for classification .

 The precipitated impurities and inclusions are discharged from the housing 13 with a small amount of pulp through a discharge valve in the bottom 14.

 In hydrocyclone 11, the pulp entering the housing 20 through the supply nozzle 21 is separated by hydraulic density with the discharge of the enriched pulp being discharged through the pipe 23 to the collecting tank 12, and the sands through the nozzle 22 to the dump.

 In the collection tank 12, the enriched pulp (acidity 0.60%, ash 1.2%) entering the housing 24 through the nozzle 26 is averaged over the composition with stirring by the mixer 27 and is transported through the nozzle 26 to the lining apparatus 28 of the installation 3 dehydration of the pulp and pressing of lignin blocks.

 In the lining apparatus 28, the lignin pulp is lined with a filter conveyor 30, where it is regulated by the thickness of the layer by the leveling drum 29 and partially dehydrated by gravity and vacuum in the vacuum chamber 38. The lignin mass thus prepared is fed by the filter conveyor to the pressing chamber 32. Formation and dehydration lignin blocks in the pressing chamber 32 is made by lowering the sliders 35, 36 and the punch 37. Moreover, to increase the degree of dehydration, the lignin blocks at the time of pressing are vibration and vacuum respectively drive the vibrating table 33 and the vacuum chamber 38.

 The squeezed water (filtrate) through a channel in a vibrating table (not shown in the drawing) is discharged into a vacuum chamber 38, and from it, after removing the vacuum, it is transported to a collection tank 39, from where it is sent to a receiving hopper 8 and / or to a hydrolysis plant for sugar extraction.

 Upon completion of the formation of lignin blocks, the sliders 35, 36 and the punch 37 are lifted and the molded lignin blocks are filtered by a filter conveyor 30 to the extendable roller table 40, and from the latter are distributed on the chain conveyor 45 of the drying unit 4.

 In a drying installation 4, lignin blocks dehydrated to a moisture content of ~ 40% are transported by a chain conveyor through a tunnel chamber 41 along a high-potential electrode 49 and, passing through a high-frequency electromagnetic field generated by it, are heated from the inner layers to the outer ones, evaporating moisture.

 The water vapor generated in this case by a directed stream of hot air pumped by the heat generator 43 is blown out of the chamber 41 into the air duct 42 and further into the atmosphere.

 Upon completion of drying, the lignin blocks are removed from the tunnel chamber 41 by a chain conveyor 45, reloaded onto a conveyor belt 53 and transported to the lignin block crushing unit 5.

 In unit 5, lignin blocks dried to a moisture content of ~ 12% are subjected to grinding to obtain a lignin mass with a particle size of minus 10 mm.

 The resulting lignin mass from under the crusher 54 is fed into the storage hopper 56 installation 6 preparation of the mixture.

 In the installation 6, the dry lignin mass from the hopper 56 through the dispenser 57 is fed to the mixer 58, where in the case of preparation of the charge for fuel briquettes it is mixed, and in the case of preparation of the charge, for example, for a carbon reducing agent used in metallurgy, it is mixed in a ratio of 1: 1 with fine-grained petroleum coke (GOST 22898-78).

 The prepared mixture from the mixer 58 is fed into the hopper 59 of the installation 7 of the pressing of fuel briquettes and / or briquettes of a complex carbon reducing agent.

 In the installation 7, the lignin mixture from the mixer 58 is fed into the hopper 59 by a screw presser 61 into the mouth between the rolls of the press 60, on the bandages of which there are cells for forming briquettes. Pressed briquettes are transported from under the press rolls to the finished goods warehouse.

 Thus, the proposed line, due to the distinguishing features made according to the invention, allows, due to the possibility of drying the lignin mass by exposing the dehydrated lignin blocks to the electromagnetic field of high frequency currents, to reduce the fire and explosion risk of drying and, moreover, due to the possibility of introducing into the lignin mass before briquetting charge additives to expand the functionality of the line.

Claims (7)

 1. The production line of briquettes from hydrolytic lignin, including a lignin pulp preparation unit, a pulp enrichment unit, a pulp dehydration unit, a drying unit with a heat carrier, a crushing unit and a lignin briquette pressing unit, characterized in that that it is equipped with a charge preparation unit placed before the installation of pressing lignin briquettes and connected by means of conveyor the crushing plant, while the pulp dehydration unit is a pulp dewatering and lignin block pressing unit, on which a lignin block pressing chamber is mounted, and the drying chamber is equipped with a high frequency electromagnetic field generator and a lignin block conveyor conveyor, by means of which the pulp dehydration unit and lignin block pressing unit are connected with crushing plant.  2. The line according to claim 1, characterized in that the installation of pulp dehydration and pressing of lignin blocks is made in the form of a lining apparatus with a filtrate collecting tank connected to the pressing chamber.  3. The line according to claim 2, characterized in that the lining apparatus is a hopper with a filter conveyor, while the pressing chamber is installed on the bed of the filter conveyor.  4. The line according to claim 1, characterized in that the drying installation is a tunnel chamber connected by an air duct to a coolant generator in a closed loop.  5. The line according to claim 1, characterized in that the conveyor transporting lignin blocks is made in the form of perforated plates of non-magnetic metal, mounted on both sides on traction chains mounted on a frame installed in the tunnel chamber.  6. The line according to claim 1, characterized in that the electromagnetic field generator of the high-frequency currents is a high-potential electrode in the form of a perforated sheet of non-magnetic metal, connected by a waveguide to a high-frequency generator, while the electrode is mounted above the conveyor for transporting lignin blocks.  7. The line according to claim 1, characterized in that the charge preparation unit is at least one storage hopper with a dispenser connected to the mixer.

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