RU2346023C1 - Wood pyrolyser - Google Patents

Abstract

FIELD: heating systems, drying.

SUBSTANCE: invention can be used when utilising industrial wood residue. Dried raw material is put into pyrolysis chamber 1. Into drying chamber 2 live wood is put. Industrial wood residue supplied to silo 26 is fed to gas-generating furnace 5 with screw feeder 14. Gases generated in gas-generating furnace 5 are supplied via gas duct to pyrolysis chamber 1. At wood warming-up stage there supplied is generator gas, with the help of gas blower 4, from pyrolysis chamber 1 through outlet branch pipe 27 and condenser 3 to burner device 7, where it is burning. Flue gases appearing during generator gas burning provide for an additional heating of raw material through pyrolysis chamber 1 wall. After that flue gases are supplied to drying chamber 2 through outlet branch pipe 31 of combustion chamber 6.

EFFECT: improving process efficiency and reducing operating costs.

1 dwg

Description

The invention relates to the field of coal production in wood-chemical production and can be used in the disposal of waste from woodworking enterprises.

A well-known charcoal furnace containing a thermally insulated housing for installing containers with wood and a firebox (see, for example, AS No. 1204627, MKI C10B 1/06, 1986).

The disadvantage of this furnace is the lack of a cooling system, which leads to an increase in the duration of the cycle and, accordingly, to a decrease in productivity. In addition, unused steam-gas mixture pollutes the environment.

There is also a carbon-burning furnace, including a thermally insulated casing for installing containers with firewood, divided into pyrolysis and drying chambers, interconnected by an air duct with a water trap, the pyrolysis chamber being equipped with a diffuser mounted in its bottom and a pipe with a blower and cooler mounted in its upper part , the pipeline from which is led under the diffuser, and the pipeline from the blower is led into the furnace (see, for example, Pat. RF No. 2081148, MKI C10B 1/06, 1994).

The disadvantages of this technical solution include the following. The blower is located at the outlet of the pyrolysis chamber in front of the cooler, which leads to its rapid failure due to the high temperature of the pyrogas (450-500 ° C). The presence of a water lock reduces the drying efficiency, since the drying agent is humidified.

The closest in technical essence and the achieved result to the claimed invention is a charcoal burning furnace containing thermally insulated pyrolysis and drying chambers for installing containers with wood, a furnace, a diffuser, a pipe with gas blowing and a cooler (see Pat. RF No. 2256686, MKI C10B 1/04 , 2004).

The disadvantages of this technical solution include the low efficiency of the drying processes and the low degree of utilization of non-condensable gases. The low drying efficiency is due to the heating of the drying agent through an intermediate coolant, and the low degree of gas utilization is caused by the fact that part of the pyrogas is released into the atmosphere to ensure the operation mode of the installation. In addition, the mixing of pyrolysis and flue gases in the combustion chamber leads to a decrease in their calorific value.

The aim of the invention is to increase the efficiency of the process, by increasing productivity, improving the environmental friendliness of the process and reducing operating costs.

This goal is achieved by the fact that in the installation for pyrolysis of wood, including a pyrolysis and drying chamber, a condenser, a gas blower, a gas furnace and a combustion chamber with a burner, the gas furnace is directly connected to the internal volume of the pyrolysis chamber; the pyrolysis chamber is located in the combustion chamber above the burner device and forms two rectangular channels with it; the combustion chamber is connected by an air duct to the drying chamber; there is the possibility of controlled selection of the excess mixture of pyrolysis and generator gas from the discharge line of the gas blower.

Comparative analysis with the prototype will allow us to conclude that the claimed technical solution is characterized in that the gas-generating furnace is directly connected to the internal volume of the pyrolysis chamber; the pyrolysis chamber is located in the combustion chamber above the burner device and forms two rectangular channels with it; the combustion chamber is connected by an air duct to the drying chamber; there is the possibility of controlled selection of the excess mixture of pyrolysis and generator gas from the discharge line of the gas blower.

Due to the fact that the gas-generating furnace is directly connected to the internal volume of the pyrolysis chamber, the possibility of oxidation of the carbonized product during the pyrolysis is excluded, which leads to an increase in the quality of charcoal. The location of the pyrolysis chamber in the combustion chamber above the burner with the presence of rectangular channels allows for more complete utilization of non-condensable gases in the burner, since they do not mix with flue gases and their calorific value does not decrease, as well as to intensify the pyrolysis process by heating the raw material through the chamber wall pyrolysis. The connection of the combustion chamber with the drying chamber allows the drying process to be carried out more efficiently due to its implementation by the hot gases supplied from the combustion chamber, and not through an intermediate heat carrier. The possibility of controlled selection of the excess mixture of pyrolysis and generator gas allows its energy use in boilers and heat engines.

The invention is illustrated in the diagram, which shows a General view of the installation for the pyrolysis of wood (see drawing).

Installation for pyrolysis of wood contains a pyrolysis chamber 1, a drying chamber 2, a condenser 3, a gas blower 4, a gas furnace 5, a combustion chamber 6, a burner 7.

The gas furnace 5 is a gas generator equipped with a screw feeder 14 with an electric drive 11, a waste bin 26 and a blower fan 12. The gas furnace 5 is hermetically closed by a door 24 and connected to the pyrolysis chamber 1 through a gate 10.

The pyrolysis chamber 1 is equipped with a hermetically sealed door 17, as well as the inlet 28 and the outlet pipe 27. A distribution grid 15 is installed inside the pyrolysis chamber. Through the outlet pipe 27, the pyrolysis chamber 1 is connected in series with the condenser 3 and the gas blower 4. The discharge line of the gas blower 4 is connected through the valves 9 , 8, 29 with a burner device 7, an inlet pipe 28 and power equipment, respectively. The pyrolysis chamber 1 is located horizontally in the combustion chamber 6 and forms two rectangular channels with it. In the lower part of the combustion chamber 6, a burner device 7 is installed horizontally in the center. Also, the combustion chamber 6 is equipped with blow holes 16 and a branch pipe 31. Through a branch pipe 31, the combustion chamber 6 is connected to the ejector 30 of the drying chamber 2. There is a tap in the upper part of the drying chamber 2 23 for exhaust gases. The chamber is hermetically closed by a door 24 located on the side. Inside the chamber there is a container 22 made of perforated metal material, on rollers 19 and a fan 18.

The process of obtaining charcoal in the installation for pyrolysis of wood is as follows.

Pre-dried raw material is placed in the pyrolysis chamber 1 and closed with a lid 17. Raw wood is placed in the drying chamber 2.

The woodworking fuel waste loaded into the hopper 26 is transferred by the screw feeder 14 in the required quantity to the gas-generating furnace 5. They are ignited through the door 24, and the gasification process begins in the gas-generating furnace 5. The productivity of the gas-generating furnace 5 is controlled by the rotational speed of the electric actuator 11, the valve 13 and the gate 10. The gases generated in the gas-generating furnace 5 are supplied through the gas duct through the inlet pipe 28 to the pyrolysis chamber 1 and are evenly distributed over the section of the pyrolysis chamber 1 due to the distribution grid 15, heating the pyrolysis feedstock.

The initial stage of the process is with the absorption of heat generated by the gas generator furnace 5. After the wood is heated 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. At the stage of heating the wood, the generator gas from the pyrolysis chamber 1 through the branch pipe 27 and the condenser 3 is fed by a gas blower 4, with the shutter 8 closed, to the burner 7, where it is burned. The flue gases generated during the combustion of the generator gas provide additional heating of the feedstock through the wall of the pyrolysis chamber 1. Next, the flue gases are supplied through the exhaust pipe 31 of the combustion chamber 6 to the drying chamber 2. In the ejector 30 of the drying chamber 2, the flue gas is mixed with air to provide the specified drying parameters agent (100-200 ° C). In the drying process of the feedstock, the circulation of the drying agent through the container 22 is carried out by the fan 18. The spent drying agent is released into the atmosphere through the outlet 23 of the drying chamber 2. Also during the process, the generator gas is taken through the valve 29 for its use for energy purposes.

Further heating of wood to a temperature of 150-450 ° C will cause the process of carbonization of raw materials. With the beginning of the carbonization process, depending on the need for combustible gas, the gate 10 is covered or closed. In this case, the course of the pyrolysis and drying of the raw material is carried out due to the heat of 7 non-condensable pyrogases burned in the burner device.

During all stages of the pyrolysis process, the vapor mixture is condensed in a condenser 3 and collected in a collector 25.

At the end of the pyrolysis process, the valve 8 opens, the valve 9 and the gate 10 close, and the process of cooling charcoal begins. Pyrogases passing through a condenser 3 are cooled and fed by gas blower 4 through a valve 8 and an inlet pipe 28 to the pyrolysis chamber 1. In the pyrolysis chamber 1, the pyrogases passing through charcoal intensively cool it.

At the end of the cooling process, door 17 opens and coal is unloaded. A container 22 with dried raw materials is removed from the drying chamber 2, which is placed in the pyrolysis chamber 1, and a new container with raw materials is loaded into the drying chamber.

Thus, the use of the proposed technical solution allows to increase the efficiency of the pyrolysis process by increasing productivity, improving environmental performance and reducing operating costs.

Claims (1)

A wood pyrolysis installation, including pyrolysis and drying chambers, a condenser, a gas blower, a gas furnace and a combustion chamber with a burner, characterized in that the gas furnace is directly connected to the internal volume of the pyrolysis chamber; the pyrolysis chamber is located in the combustion chamber above the burner device and forms two rectangular channels with it; the combustion chamber is connected by an air duct to the drying chamber; there is the possibility of controlled selection of the excess mixture of pyrolysis and generator gas from the discharge line of the gas blower.