RU2256686C1 - Charcoal kiln - Google Patents

Abstract

FIELD: wood-chemical production.

SUBSTANCE: the invention is pertaining to the field of resin industry, in particular, to wood-chemical production and also intended for production of charcoal and for complex utilization of wood wastes. The charcoal kiln contains a heat-insulated chamber of pyrolysis and drying used for installation of containers with firewood, a fire box, a scatter, a pipeline with an air blower and a cooler. At that the drying chamber is supplied with a heater and it is stand-alone unit. The scatter represents vertically placed perforated headers fixed in the lower part of the container communicating with a gas duct of the fire-box through a compactor. The fire box is made in the form of in series connected a gas generator and a combustion chamber. The pipeline is supplied with a heat insulation. The cooler is made in the form of a jacket-tubular heat-exchanger, the inter-pipe space of which is connected with the heater of the stand-alone drying chamber and the air blower is located behind the cooler. The invention allows to improve the operational characteristics of the charcoal kiln at production of the high quality charcoal.

EFFECT: the invention ensures improved the charcoal kiln operational characteristics at production of the high quality charcoal.

1 dwg

Description

The invention relates to the field of coal production in the wood-chemical industry.

A well-known charcoal furnace containing a thermally insulated casing for installing containers with wood and a firebox (see, for example, AS USSR No. 1204627, MKI C 10 V 1/06, 1986).

The disadvantage of this furnace is the lack of a gas distribution system, which dramatically reduces the yield of coal due to its burnout in the upper part of the furnace and the formation of smut in the lower part.

The closest in technical essence and the achieved result to the invention is a charcoal incinerator, including a thermally insulated casing for installing containers with wood, divided into pyrolysis and drying chambers, interconnected by an air duct with a water seal, and the pyrolysis chamber is equipped with a diffuser mounted in its bottom and mounted in its upper part by a pipeline with a blower and a cooler, the pipeline from which is led under the diffuser, and the pipeline from the blower is led into the furnace (with ., For example, Pat. RF №2081148, IPC C 10 B 1/06, 1994).

The disadvantages of this technical solution include the following. The design of the diffuser in the form of a horizontal perforated plate leads to a decrease in the quality of the obtained charcoal due to the uneven distribution of temperature along the height of the chamber: overheating in the upper part and underheating in the lower part of the pyrolysis chamber. The location of the blower at the outlet of the pyrolysis chamber (pyrogas temperature 450-500 ° C) in front of the cooler leads to its rapid failure. In addition, in the well-known charcoal furnace, a significant part of the heat of the pyrogases is not utilized.

The aim of the invention is to improve the operational characteristics of the charcoal furnace with high quality charcoal.

This goal is achieved by the fact that in a carbon-burning furnace, including heat-insulated pyrolysis and drying chambers for installing containers with wood, a furnace, a diffuser, a pipe with a blower and a cooler, the drying chamber is equipped with a heater, made autonomous; the diffuser is a vertically arranged perforated manifolds mounted in the lower part of the container, communicating with the flue of the furnace through the seal; the furnace is made in the form of a series-connected gas generator and a combustion chamber; the pipeline is insulated; the cooler is made in the form of a shell-and-tube heat exchanger, the annular space of which is connected to the heater of an autonomous drying chamber, and the blower is located after the cooler.

Comparative analysis with the prototype allows us to conclude: the claimed technical solution is characterized in that the drying chamber is equipped with a heater, made autonomous; the diffuser is a vertically arranged perforated manifolds mounted in the lower part of the container, communicating with the flue of the furnace through the seal; the furnace is made in the form of a series-connected gas generator and a combustion chamber; the pipeline is insulated; the cooler is made in the form of a shell-and-tube heat exchanger, the annular space of which is connected to the heater of an autonomous drying chamber, and the blower is located after the cooler.

Thanks to perforated vertically located collectors, a rational structure of the movement of flue gas inside the pyrolysis chamber and uniform heating of the entire volume of wood is ensured, which makes it possible to obtain coal with high quality characteristics. The implementation of the cooler in the form of a shell-and-tube heat exchanger allows not only to reduce the cooling time of the finished coal, which leads to a decrease in the process time as a whole, but also to collect liquid pyrolysis products, and use the utilized heat to dry the pyrolysis feed in an autonomous drying chamber. The implementation of the furnace in the form of a series-connected gas generator and combustion chamber allows you to process illiquid raw materials from woodworking and sawmilling, charcoal fines, as well as utilize gaseous combustible pyrolysis products. Thermal insulation on the pipeline does not allow heavy resins to condense on the pipe walls and prevents heat loss. The presence of a seal between the container and the flue ensures a uniform supply of flue gases to the collectors. The implementation of the autonomous drying chamber provides a more stable course of the pyrolysis process, and also allows you to use the heat of pyrogas for drying wood raw materials, and for other technological purposes.

The invention is illustrated by the drawing, which shows a General view of the charcoal furnace (side view).

The coal burning furnace contains a pyrolysis chamber 1, a furnace 2, a cooler 3, a drying chamber 4. The housing of the pyrolysis chamber 1 is made of welded steel sheets and provided with heat insulation to prevent heat loss 5. The container 6 is equipped with perforated collectors 7 fixed to the bottom of the container. The container is connected to the flue gas duct 8 by means of a sealing assembly consisting of a seal 9 embedded in a groove and a sealing collar 10. The flue gas duct is equipped with a slide gate 11. The pyrolysis chamber is closed from above by a cover 12 through a sealing assembly consisting of a seal 13 embedded in a groove , and a sealing collar 14. The furnace 2 consists of a series-connected gas generator 15 and a combustion chamber 16. The gas generator is equipped with a screw feeder 17 with an electric drive 18, a waste bin 19 and a belt conveyor 20. Gas generator the pipe 21 is connected to the combustion chamber 16, which consists of the main gas burner 22 and the burner of the afterburner of non-condensable pyrogases 23 and is equipped with turbulators 24 to stabilize the flame 24. A blower 27 is connected to the gas generator 15 with a discharge pipe 25 provided with a valve 26. The blower 27 is also connected to the combustion chamber 16 by a pipe 28 provided with a valve 29. The pyrolysis chamber in the upper part of the pipe 30 communicates with a condensation system including a vapor-gas mixture cooler 3 and a condensate collector 31, connected enny conduit 32 with blower 33. The conduit 34 is connected to conduit 36 via valve 37 with the combustion chamber 16, the conduit 38 through the valve 39 to the gas duct 8, and through valve 35 to the atmosphere. The annular space of the cooler by 3 pipelines 40, 41 is connected to the heaters 42 of the drying chamber 4. The pipelines 30, 40, 41 are provided with thermal insulation.

The pyrolysis chamber 1 has a number of technological holes for installing thermocouples 43, 44 and a metal probe 45 for monitoring the readiness of coal. In the inoperative state, the holes are closed with threaded plugs.

The drying chamber 4 is a structure similar to the pyrolysis chamber 1, additionally equipped with heaters 42, a blower 46 and a hatch for drying air 47.

The process of obtaining charcoal in the considered charcoal furnace is as follows. The container 6 with pre-dried wood is loaded into the pyrolysis chamber 1 and closed with a lid 12. Another container with raw wood is placed in the drying chamber 4.

Illiquid woodworking waste loaded into the hopper 19 by a belt conveyor 20, is fed by a screw feeder 17 in the required amount to the gas generator 15. The blower 27 is turned on, the valve 26 of the discharge pipe 25 is opened. After the raw materials are ignited in the gas generator through the door 48, the gas generation process begins. The generator gas produced by the gas generator, through the pipe 21 enters the combustion chamber 16. Through the combustion door of the combustion chamber 49, the main burner 22 is set on fire and the valve 29 of the discharge pipe 28, which feeds air to the combustion chamber 16, opens.

After ignition of the combustion chamber, the blower 33 is turned on, the slide gate valve 11 and the shutter 35 open, the shutters 39 and 37 are closed.

Flue gases pass through a gas duct 8 and perforated collectors 7, are distributed over the entire area of the pyrolysis chamber 1, uniformly heating the pyrolysis raw materials, and, when cooled, are released into the atmosphere.

The initial stage of the carbonization process is with the absorption of heat generated by the furnace. After the wood warms up to a temperature of 120-150 ° C, the loss of bound moisture occurs and the decomposition of less stable organic substances begins with the formation of carbon dioxide, carbon monoxide and acetic acid. Further heating of the wood to a temperature of 150-275 ° C will cause a process of carbonization. With the start of the carbonization process, the valve 35 is closed and the valve 37 is opened. Non-condensable gases are fed through the pipe 36 to the afterburner to the combustion chamber. Closing the gate valve 26 leads to a decrease in the production of generator gas, and the process flow is supported by the afterburning of non-condensable gases.

The progress of the carbonization process is controlled by the temperature in the upper and lower parts of the pyrolysis chamber, measured by thermocouples 43, 44. The temperature can be controlled by opening or closing the shutters 26 and 29 of the discharge pipelines 25 and 28. At a temperature of 275-450 ° C, rapid heat generation and the formation of the main the amount of decomposition products. Calcination of coal and the removal of volatile substances occur at a temperature of 450-550 ° C.

Coal readiness is determined by probing the products of carbonization in the chamber with a metal probe 45 through the holes in the lower part of the pyrolysis chamber body and in the container according to the value of puncturing resistance.

During all stages of the wood carbonization process, the vapor mixture is condensed in a shell-and-tube heat exchanger 3 and collected in a collector 31. The coolant from the annular space of the heat exchanger 3 is pumped to the heaters 42 of the drying chamber or discharged to the consumer using the pump 50.

At the end of the pyrolysis process, the gate 11 and the valve 37 are closed, the valve 39 is opened, the process of cooling charcoal begins. Pyrogas, passing through a shell-and-tube heat exchanger 3, are cooled and fed through a pipe 38 to the flue gas duct 8, where, dispersed through the perforated collectors 7, they rise upwards and, passing through a layer of finished coal, intensively cool it to 50 ° C.

At the end of the cooling process, thermocouples are removed. Then the lid 12 opens with a telpher and the container and coal are unloaded from the container and the container with the dried raw material is installed in the pyrolysis chamber, and the container with the raw material prepared for drying is put into the drying chamber.

Thus, the use of the proposed technical solution allows to increase the operational characteristics of the installation and the quality of charcoal subjected to carbonization in the installation, by ensuring stable process conditions in all parts of the chamber and reducing the time of the technological process as a whole and increasing the efficiency of the furnace.

Claims (1)

Coal burning furnace, including heat-insulated pyrolysis and drying chambers for installing containers with wood, a furnace, a diffuser, a pipe with a blower and a cooler, characterized in that the drying chamber is equipped with a heater, made autonomous; the diffuser is a vertically arranged perforated manifolds mounted in the lower part of the container, communicating with the flue gas duct through the seal; the furnace is made in the form of a series-connected gas generator and a combustion chamber; the pipeline is insulated; the cooler is made in the form of a shell-and-tube heat exchanger, the annular space of which is connected to the heater of the autonomous drying chamber, and the blower is located after the cooler.