Three temperature stages of the new carbonization furnace

Three temperature stages of the new carbonization furnace

The drying stage

 starts from ignition until the furnace temperature rise to 160°C. At this time, the moisture contained in the machine rod mainly depends on the external heat and the heat generated by its own combustion to evaporate. The chemical composition of the mechanical rods has hardly changed.

The initial stage of carbonization

 This stage mainly relies on the combustion of the rod itself to generate heat, so that the furnace temperature rises to between 160 and 280 °C. At this time, the wood material undergoes a thermal decomposition reaction, and its composition begins to change. Among them, unstable components, such as hemicellulose, are decomposed to generate CO2, CO, and a small amount of acetic acid.

 Full carbonization stage

 The temperature in this stage is 300 to 650°C.

During this stage, the wood material undergoes rapid thermal decomposition, and a large number of liquid products such as acetic acid, methanol, and wood tar are produced. In addition, flammable gases such as methane and ethylene are produced, and these flammable gases are burned in the furnace. Thermal decomposition and gas combustion generate a large amount of heat, which increases the furnace temperature, and the wood material is dry-distilled into charcoal at high temperatures.

To calcine high-temperature charcoal, in addition to the above three stages, we also need to increase the heat, so that the temperature in the furnace continues to rise to about 800 ° C ~ 1000 ° C so that the volatile substances remaining in the charcoal can be discharged, and the charcoal content can be increased. The carbon content of carbon increases the graphite structure of carbon and enhances the conductivity. Carbonization is an important part of making charcoal. The carbonization process is the core of the production technology of machine-made charcoal. It's like building a building. Good materials are the base of the building in the underground part. The carbonization technology in the carbonization process is the above-ground part of the building. Carbonization is divided into three stages: low-temperature exhaust, high-temperature calcination, and cooling. When the salary rod enters the carbonization furnace, it has about 8% moisture, which is the enemy of carbonization. Because the mechanism salary rod is most afraid of moisture, the moisture in the salary rod will seriously affect the carbonization quality. Therefore, drain time is essential. The moisture removal time is generally 10-15 hours for earth kilns and 2-3.5 hours for machine-made kilns. Long heating time can prevent the rods from being damp and cracked and ensure the quality of carbonization. When the furnace temperature rises to 300 degrees, a large amount of combustible gas can be produced in the furnace. It is reasonable to say that three cubic meters of methane gas can be produced per kilogram of raw materials. These gases are used to heat the furnace. The discharge can be used for drying heat sources above 400 degrees. It is necessary to seal the anaerobic closed fire in the heat preservation and calcination stage. It can be taken from spontaneous combustion or water cooling. After the charcoal leaves the kiln, it must be ventilated before the charcoal is discharged to prevent carbon dioxide poisoning. The charcoal coming out of the kiln should be placed outdoors for more than 8 hours. To prevent the resurgence of ashes, resulting in a fire.