VietNamNet Bridge - Using pyrolysis technology, Phan Van Tuan has successfully built up a process of making smokeless coal which is friendly to the environment and safe for users.

Coal stoves remain the choice of many Vietnamese thanks to low cost and high convenience. However, this is not a good choice because of the environmental problems. 

Coal produces substances harmful to the environment and human health during the combustion process such as NO2, SO2, CO and CH4. Regular contact with the toxic gas will cause cancer and other serious diseases, while the inhalation of gases will cause respiratory diseases to children.

Tuan, an engineer from Bui Gia Transport and Construction Works Company, understands that some types of gas generated during the burning process like CO, CH4 and acetone are all combustible gases and they can produce heat. 

He also learned that in some developed countries, combustible gases can be applied to generate heat and help minimize fuel consumption.

In Vietnam, Pham Thuy Phuong and her co-workers from the Institute of Chemical Technology in 2012 successfully invented a version of a furnace utilizing the principle.

The coal furnace uses the direct pyrolysis method (the heat from incineration chamber creates a direct impact on firewood and generates the carbonization process).

The great advantage of the furnace is that it can be built at a low cost, the combustion technology is simple and it is suitable to many different types of materials.

However, there is a big disadvantage that it cannot run continuously. It takes 24 to 30 hours to cool down to get charcoal. Therefore, it cannot be used to make coal in large quantities.

Tuan and his co-workers, aware of the problems, invented a furnace that runs on a close process which comprises a combustion chamber, firewood containing tank, condensers and air circulation system.

When the furnace operates, the heat from the combustion chamber will be brought directly to the firewood tank where the carbonization process takes place. The gases to be generated during the process will be collected in condensers and will be brought back to the combustion chamber through the air ventilation system.

According to Tuan, with the method, users will only need to use fuel once, because the heat to be generated during the combustion will be re-used many times. As the firewood tank is replaceable, users don’t have to wait while they can change the tanks to maintain continuous production.

Tuan’s furnace not only can help minimize the toxic gases to be discharged into the environment, but the coal created by the furnace gives blue flame and produces very little smoke.

Kham Pha