FIELD OF INVENTION
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The inventions refer to the field of industrial processing of combustible carbon-and/or hydrocarbon-containing products and can be used for processing of different technogenic and domestic wastes, including solid fuel wastes such as wood powder, cinder, fine, dust, waste of brewing industry, brewer's grains and also fossil fuel, including brown coal, combustible shale and similar materials.
BACKGROUND OF INVENTION
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There is method of pyrolysis and gasification of soli organic substances or mixtures of organic substances that provides for injection of raw material into one or several drying and pyrolysis reactors, consisting of one or several moving-bed reactors or one or several rotating reactors and moving-bed reactors that ensure contact with material of fluidized bed, resulting in generation of water vapor and pyrolysis products that consist of gases with condensables and solid carbon residuals; feeding of solid carbon residuals, part of water vapor, pyrolysis gas with condensables and material of fluidized bed back to fluidized bed of combustion, where carbon residue of organic substances burns down, material of fluidized bed is heated and fed to back to pyrolysis reactor, where pyrolysis residuals, used as fixed fluidized bed, are burnt down. Dried water vapor and pyrolysis gases with condensables are processed in separate reaction zone of indirect heat exchanger with adding of vapor, oxygen, air or their mixture into pyrolysis gas or heat exchanger in order to create gaseous product of high calorific capacity, in which exhaust gases, generated during combustion, and material of fluidized bed from combustion fluidized bed contact in reactor zone of heat exchanger, using their calorific capacity for Interaction of pyrolysis gases with vapor, oxygen, air or their mixture [description of invention to license of the Russian Federation No. 2272064 OT 27 Jun. 2000, MΠK C10G 9/32, C10J 3/54, C10J 3/56, C10B 49/16, C10B 49/10, C10B 49/22, C10K 3/00, published on 20 Mar. 2006]
SUMMARY OF INVENTION
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The process is developed in order to prevent zone-based treatment of wastes in one unit due to uncertainty of area borders. There for it is proposed to use several units reactors) instead of one unit for generation of gas with high calorific capacity and at high temperatures ((500-900° C.):
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Reactor for pyrolysis in fluidized bed;
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Reactor for combustion of carbon residual in fluidized bed;
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Heat exchanger reactor with catalytic agent.
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Reactors are bind with counterflow in gas phase. This may cause problems upon their operation since it is necessary to maintain equality of material flows and fluidizing velocity in every reactor. Instruments and controls, operating under above-mentioned conditions, are specially designed for this process.
BRIEF DESCRIPTION OF THE DRAWINGS
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FIG. 1 shows method for processing of combustible carbon- and/or hydrocarbon-containing products and reactor.
DETAILED DESCRIPTION
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Presence of hydrogen in fed air and, respectively, obtained gas results in reduction of its calorific capacity and catalytic process velocity in reacting zone (heat exchanger reactor). Gummy products, fed to heat exchange reactor with catalyst agent, can deactivate it that will cause decrease of calorific capacity of resulted gas and replacement of catalytic agent.
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There is method for coal processing with production of heat-treated solid fuel and heat power that includes thermal oxidative treatment of milled coal up to 10 mm in fluidized bed, In this case processing is carried out by simultaneous thermal oxidative processing of coal a temperature of 700-900° c. by partial oxidizing of coal with air and separation of coal mineral part that. is heavier than coal with decrease of ash content of resulted heat-treated solid fuel and milled coal is used as initial raw material. Blasting air is fed to fluidized bed in the volume of 2500-4200 m3/(m2 ×h) [description of invention to license of the Russian Federation No. 2401295 dated 26 Aug. 2009, MΠK C10B 49/10, published on 10 Oct. 2010].This method increases efficiency and simplifies coal processing procedure due to exclusion of the stage of preliminaty beneficiation of raw coal.
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This method provides for preliminary preparation of coal so that its size doesn't exceed 10 mm. This requires special equipment and processing may result in unprocessed coal dust and cinder.
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Gas, produced upon combustion of pyrolysis products and entrained coal particles in fluidized bed, consists of CO2, H2O and N2 and can be used as power fuel as it has almost zero calorific capacity. Moreover, coal particles, mixed with main and auxiliary air, can create explosive mixtures.
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We also know method for processing of combustible carbon- and/or hydrocarbon-containing that includes layer-by-layer high temperature processing of above-mentioned materials in reactor in presence of nozzle upon feeding of oxygen-containing agent and water vapor, combustion, carbonization, pyrolysis of combustible components, generation of as vapor mixture and solid residuals, their cooling, removal and extraction from working space of reactor. Hydrocarbon synthesis and pyrolysis area with temperature of 250-400° C. is created directly after carbonization area, temperature of 850-1300° C. is maintained in combustion area, free carbon is extracted in carbonization and pyrolysis area and treated with water vapor in combustion area with generation of free hydrogen that is fed in synthesis and hydration area, while executing synthesis and hydration of hydrocarbons. Rarefaction is created inside working space of reactor and the process is maintained in the presence of catalytic agents that is included into composition of nozzle [description of invention to license of the Russian Federation No. 2385343 dated 10 Dec. 2008, MΠK C10B 49/02, F23G 5/027]. This procedure reduces energy capacity of the process, while expounding process opportunities in the file of control of chemical composition, increasing output of finished products and improving their quality.
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The disadvantage of this method is high emergency capacity of the process due to high cost of injected hydrocarbon, necessity in use of large amount of processed material for maintaining combustion process. If wood waste is used this method reduces economic feasibility of such processing.
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This method doesn't provide for broad technological possibilities in terms of control of chemical composition and increase of the output of finished products. Possibilities for improvement of the quality of finished products are not realized.
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There are special devices for processing of combustible carbon- and/or hydrocarbon-containing products.
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There is a device that contains pyrolytic shaft and rotating reactor, fluidized bed for combustion of pyrolytic residual, reactive area for pyrolytic gases. Circulation of material of fluidized bed between fluidized bed of combustion and pyrolytic reactor is provided. Reactor that have gastight design for feeding of used material and inlet hole for feeding of material of fluidized bed from fluidized bed of combustion is located close to fluidized bed of combustion. Pyrolytic reactor contains helical elements on its bottom end for transfer of fluidized bed, containing overflow for transfer of material of fluidized bed to specified reactor. Fire gases of fluidized bed can be fed to reactive area of heat transfer that is connected to pyrolytic gas reactor [see description of invention to license of the Russian Federation No. 2272064].
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This device is characterized by disadvantages of procedure, for which it is designed.
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There is also reactor for processing of combustible carbon- and/or hydrocarbon-containing products that includes leakproof process chamber with process zones, located in technological order: area for discharging of processed solid residuals with discharging gate, area for feeding of the air and water vapor through corresponding channels, air and water vapor heating area, combustion areas, carbonization and pyrolysis area, derivate products heating area, gas and vapor mixture take off area with, at least, one take off channel and derivative product charging area with gate. Every zone is fitted with, at least, one temperature gauge. Air and water vapor heating zone and vapor-gas mixture take off zone are fitted with pressure gauges. Process chamber contains hydrocarbon synthesis and hydration zone that is located directly after pyrolysis and carbonization zone [see description of invention to license of the Russian Federation No. 2385343].
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This reactor is also characterized by disadvantages of procedure, for which it is designed.
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The solution, solved by this invention, arid achieved technical result are represented by extension of process possibilities for recycling of combustible carbon- and/or hydrocarbon-containing products that will result in complete utilization of processing products, including their small fractions, increase of calorific capacity of vapor-gas mixture, additional heat supply into combustion zone and simplification of water supply to reactor area, omitting super-heated steam preparation stage. As a result emergency capacity of the process is maintained due to cheaper wastes that were not recycled formerly. This provides possibility for controlling chemical corn position, increasing the output of finished products and ensuring their maximum quality, considering such method of treatment.
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For solution of set task and reaching of claimed technical result in the method for processing of carbon- and/or hydrocarbon-containing products that includes preparation of raw materials from derivative products and their consequent layer-by-layer treatment in reactor in the presence of catalytic agents, included into composition of nozzle, upon movement of raw material and nozzle from the top downward in the course of feeding of oxygen-containing agent and water vapor to reactor from bottom upward and including stages of raw material heating, pryrolysis of combustible components, carbonization, combustion, generation of solid residual that is discharged from process space of reactor, generation of vapor-gas mixture, cooling of vapor-gas mixture and its extraction from process space of reactor, rarefaction is created inside processing space of reactor, wet small particles of solid fuel waste are injected, into flow with their transition to liquidized state upon feeding of oxygen-containing agent into reactor from the bottom upward, additional volume of oxygen-containing agent is injected into reactor as a part of main flow that is necessary for further combustion of small particles of solid fuel waste that passed through pyrolysis and carbonization and conversion of their moisture into superheating steam and discharge is performed cyclically with maintenance of sealing of reactor processing space.
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Moreover:
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Rings from nickel-containing heat-resistant steel are used as nozzle.
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Wood dust, starch, coal dust or similar materials are used as solid fuel Waste.
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Reactor for processing of combustible carbon- and/or hydrocarbon-containing products includes process chamber with process areas, located in technological order: area for discharging of processed solid residuals with discharging gate, area for feeding of oxygen-containing agent, area for heating of oxygen-containing agent, combustion area, carbonization area, pyrolysis area, area for heating of derivative products and area for loading of resulted products with gate. Process chamber contains area for feeding of wet small particles of solid fuel waste, their pyrolysis and carbonization, connected to areas for feeding and heating of oxygen-containing agent. Channel for feeding of oxygen-containing agent is connected to metering hopper of wet small particles of solid fuel wastes with possibility for generation of fluidized flow in corresponding area inside reactor.
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Moreover:
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Hopper of small particles of solid fuel waste is equipped with dosing, auger and water dozer that is connected to burners, installed at the top of hopper. Hopper is also equipped with level gauge and humidity gauge;
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Area for discharging of solid wastes is made in the form of gate with two locks.
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Inventions are illustrated on drawing of reactor for processing of combustible carbon- and/or hydrocarbon-containing products that realizes corresponding method.
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Method for processing of combustible carbon- arid/or hydrocarbon-containing products is realized in corresponding reactor (lining and control instruments are omitted for clarity) that includes leak-tight process chamber (housing) 1 with process zones, located in technological order: area for discharge of processed solid residuals (2) with discharging gate (3), area for feeding of oxygen-containing agent (and water) (4), area for heating of oxygen-containing agent (and water) (5), combustion area (6), carbonization area (7), pyrolysis area (8), area for heating of derivative products (9), vapor-gas take off area (10) with, at least, one take off channel (11), derivative product discharging area (12) with gate (13). Process chamber 1 contains for feeding of wet small particles of solid fuel waste, its carbonization and pyrolysis (14), connected to areas for feeding of oxygen-containing agent (and water) (4) and heating (5). Channel for feeding of oxygen-containing agent (15) is connected to metering hopper of wet small particles of solid fuel wastes (16) with possibility for generation of fluidized flow in corresponding area (14) inside reactor (1). Dozer unit (16) of wet small particles of solid fuel waste is represented by dosing auger. Hopper (16) is equipped with water dozer (17) that is connected to burners (18) and installed at the top of hopper and also includes level gauge (19) and humidity gauge (20); Area for discharging of solid wastes (2) is designed in the form of gate (21) with two locks (22).
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Method for processing of combustible carbon- and/or hydrocarbon-containing products includes preparation of raw materials from derivative products and their consequent layer-by-layer treatment in reactor in the presence of catalytic agents, included into composition of nozzle, upon movement of raw material and nozzle from the top downward in the course of feeding of oxygen-containing agent and water vapor to reactor from bottom upward and including stages of raw material heating, pryrolysis of combustible components, carbonization, combustion, generation of solid, residual that is discharged from process space of reactor, generation of vapor-gas mixture, cooling of vapor-gas mixture and its extraction from process space of reactor (process chamber 1). Rarefaction is created inside processing space of reactor. Wet small particles of solid fuel waste are injected into flow with their conversion to liquidized state upon feeding of oxygen-containing agent into reactor from the bottom upward, additional volume of oxygen-containing agent is injected into reactor as a part of main flow that is necessary for further combustion of small particles of solid fuel waste that passed through pyrolysis and carbonization stages and conversion of their moisture (and additional water if small particles of solid fuel wastes are not wet enough) into superheating steam and discharge is performed cyclically with maintenance of sealing of reactor processing space.
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Rings from nickel-containing heat-resistant steel omitted for clarity) are used additionally as nozzle. Wood dust, starch, coal dust (including cinder and power) or similar materials are used as solid fuel waste. Let's analyze the following features of inventions.
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Wet small particles of solid fuel waste are injected into now with their conversion to liquidized state upon feeding of oxygen-containing agent into reactor from the bottom upward. Additional volume of oxygen-containing agent is injected into reactor as a part of main flow that is necessary for further combustion of small particles of solid fuel waste that passed through pyrolysis and carbonization stages and conversion of their moisture into super-heating steam. Thus, bottom part of reactor 23 becomes independent (the second) reactor with bottom feeding of derivative products and common combustion area (6) in single housing (1). This requires additional sealing of process space of reactor therefore solid, residual should be discharged for reactor
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This is quite enough for ensuring ecological safety of the process with minimum costs.
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Catalyst, included into composition of nozzle, is required for improvement of reactor performance. One of the main requirements is long service life. Nickel, included into composition of rings from heat-resistant steel, meet these requirements.
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So called “the second reactor” uses the cheapest non-recyclable raw materials, namely solid fuel wastes such as wooden dust, starch, coal dust (including cinder and powder) or similar materials, for example, brewer's grains. It is necessary to consider that recycling of such wastes on the basis of new technology becomes cost effective.
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As for reactor, its process chamber 1 contains area for feeding of wet small particles of solid, fuel wastes, their pyrolysis and carbonization (14), adjacent to area for feeding of oxygen -containing agent (and water) (4) and area for heating of oxygen-containing agent or water (5). For technical point of view such solution of process chamber 1 is considered to be structurally incorrect as it “pollutes” oxygen-containing agent. Connection of its channel (15) to memetering hopper of wet small particles of solid fuel wastes (16) deepens this problem. Technological contradiction is evident. However, formation of fluidized flow from wet small particles of solid fuel wastes in corresponding area (14) inside reactor is the reflection of the fact that “convenient” reactor with top feeding of war material from derived products includes feeding of additional derived products but with bottom loading.
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This allows (see above) gaining of some technological, benefits that are peculiar for two independent devices by structurally simple methods, namely due to parametrical reserve of reactor. In order to ensure optimal parameters of reactor performance dozer for wet small particles of solid fuel waste (16) of hopper (16) is represented by dosage auger. Meter hopper contains (16) contains level gauge (19) and humidity gauge (2), connected to burners (18), and water dozer (17). Reactor remains unchanged in all other aspects except the fact that area for discharge of solid residuals 2 is equipped with gate 21 with two lockers 22. This ensures necessary leakproofness of process chamber (housing) 1.
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The essence of invention is performance of “double gasification” in one apparatus, when hydrocarbon and/or hydrocarbon-containing raw material is fed from the top in the form of bricks or pellets, pieces or chips in namely turf, coal, wood and waste (liquid hydrocarbons can be used for irrigation) and wet chips and coal dust are fed together with air or oxygen-enriched air in fluidized from the bottom, Every type of raw material, supplied from the top and bottom, passes through heating areas 9 and 5, pyrolysis and carbonization areas 8, 7 and 14. Combustion area 6 (oxidation area) is common for top and bottom flow of raw materials. Wet chips and/or coal dust, brewer's grains or similar materials are carriers of hydrocarbon and water vapor.
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Water separates upon heating and evaporation. Acetic acid, pyrolysis water and tars are extracted upon pyrolysis. Main component of tars is carbonic acid. Carbonic acid and acetic acids oxidizes with oxygen up to CO2 and H2O. Water and carbonic dioxide participate in reactions with hydrocarbon CO2+C=2CO, at combustion area.
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Water vapor interacts with hydrocarbon according to the reaction C+H2O═CO+H2 at temperature above 850° C.
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These reactions are ensured by heating of surface of the rings that are similar to Rasching rings from heatproof stainless steel that contains up to 23-30% of nickel, being catalyst for these processes, up to 1000° C., This nozzle, having large free volume and developed surface, ensures the following:
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Identification of all above-mentioned processes of heating, evaporation, pyrolysis, carbonization and combustion oxidation);
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Process high-ash raw materials with dry ash extraction.
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Since combustible part of wastes (chips and other materials) is oxidized up to CO
2 and H
2O in fluidized bed of the air in reactor, this results in generation of heat for maintenance of temperature regime in reactor and carrying out endothermic reactions CO
2+C=2CO— 41 kcal/mol and C+H
2O— 31 kcal/mol, including some part of hydrocarbon, extracted from raw materials, fed from the top. Generated CO and H
2 increase calorific capacity of exhaust gas of reactor that may be used in boilers for production of hot water and water vapor. Thus, complete recycling, of wastes is ensured without additional energy consumption.
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Exhaust gas, generated during recycling of tears, tars, bitumen, oil sand, bogheads, shales etc , can be used for synthesis of different fuels, production of raw materials fir chemical industry. This is parametrial reserve of developed technology.
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Inventions are illustrated by the following example.
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Continuous reactor with functional diameter of 1500 mm and cylindrical part 10000 mm high, working capacity of 1.8m3 was used for realization of the method. Wood briquettes with humidity of 15% wt, and wood dust with humidity of 50% wt, were used as combustible products for recycling.
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Prepared raw materials from briquettes, including nozzle from heat-resistant steel rings, were loaded through leakproof flood gates 24 into upper part of process chamber 1 of reactor, where not big but stable, rarefaction was maintained.
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Oxygen-containing agent and wet wood dust, taken from metering hopper (16) with their conversion into fluidized state by means of air flow, generated by special device (25) (fan, blower etc.), and also additional volume of oxygen-containing agent as a part of main flow, necessary for further combustion of wood dust that passed states of pyrolysis, carbonization and conversion of their moisture to superheated steam, were simultaneously fed to reactor from bottom upward though special channel (15).
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Heating of raw materials, pyrolysis of combustible components, carbonization, combustion and generation of fixed residual, discharged from working space of reactor cyclically and retention of its leakproofness, took place while movement of raw material (main flow of processed products) from the top downward. Solid residual was separated from heatproof rings by means of mesh screens that were repeatedly sent for preparation of raw material i.e. mixing with wooden briquettes.
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Chemical processes, accompanied b emission of additional heat, took place during recycling of wood dust while it moves from bottom upward. This optimized heat and chemical processes that took place upon layer-by-layer processing of main flow of raw material.
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This process resulted in generation of vapor-gas mixture, heated from 150° C. to 220° C. This vapor-gas mixture Was extracted from working space for further utilization.
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Comparative analysis of processing of wood briquettes with humidity of 15% wt. in presence of nozzle from heatproof steal, available in two variants, is represented below.
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The 1st variant. Wood briquettes are recycled with the rate of 2000 kg/h without bottom feeding of wood dust. Table 1 shows composition of gas at the output of reactor.
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TABLE 1 |
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Component name |
Quantity, kg/h |
Percentage, weight |
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|
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Water vapor |
725 |
15.5 |
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Carbon dioxide |
272 |
5.8 |
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Carbon oxide |
1208 |
25.8 |
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Carbonic mixture |
212 |
4.5 |
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Acetic acid. methanol |
85 |
1.8 |
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Methane |
70 |
1.5 |
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Hydrogen |
16 |
0.3 |
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Nitrogen |
2098 |
44.8 |
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Total |
4685 |
100 |
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|
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Calorific capacity of gas is 1322 kcal/kg
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The 2nd variant: Wood briquettes are recycled with the rate of 2000 kg/h with feeding of dust at rate of 200 kg/h together with an under humidity of 50% wt. upon creation of fluidized bed inside reactor. Table 2 shows composition of gas at the output of reactor.
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TABLE 2 |
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Component name |
Quantity, kg/h |
Percentage, weight |
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|
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Water vapor |
725 |
15.1 |
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Carbon dioxide |
272 |
5.6 |
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Carbon oxide |
1383 |
28.7 |
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Cabonic mixture |
212 |
4.4 |
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Acetic acid. methanol |
85 |
1.8 |
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Methane |
70 |
1.5 |
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Hydrogen |
33 |
0.7 |
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Nitrogen |
2033 |
42.2 |
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Total |
4813 |
100 |
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|
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Calorific capacity of gas is 1479 kcal/kg
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Thus processing of wood dust with bottom feeding of wet wood dust to output of reactor through take off channel 11 results in generation of gas with higher calorific capacity (approximately by 11.9%).
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In order to reach the same result it is also possible to use briquetted industrial and domestic wastes, tires, non-carbonized coal, turf, brown coal etc. It is also possible to use coal fines, brewer's grains, starch, slats and similar materials, i.e. products that were not commercially recycled formerly. As a result percentage of most significant components will change significantly-upon expressed trend for increase of calorific capacity of gas. Realization of inventions results in extension of technological possibilities for recycling of combustible carbon- and/or hydrocarbon-containing products. This allows ensuring complete utilization of derivative products, including their small fractions, increasing calorific capacity of vapor-gas mixture, supplying additional heat to combustion area and simplifying process of feeding of water to reactive area. Moreover, this invention provides possibility for maintaining of energy capacity of the process due to use of cheap, almost unrecyclable wastes, controlling chemical composition, increasing output of finished products, ready for further use, and ensuring maximum quality, considering such method of treatment.
