Biogas cleaning equipment

Patent No. 1-0032321 “Biogas cleaning device and biogas cleaning system including this device” published on June 27, 2022, was granted to Dr. Nguyen Tuan Minh and colleagues from the Institute of Environmental Technology, Vietnam Academy of Science and Technology. The invention is in the field of environmental biotechnology.

Biogas is an extremely valuable source of energy derived from the biomass of wastewater treatment plants, livestock farms and landfills that is increasingly recognized worldwide as a high-end renewable energy source and a major contributor to the global energy supply by replacing existing fossil fuel sources like coal, oil and gas. Currently, besides the common use of biogas at the scale of households and livestock farms in many territories of Vietnam, domestic scientists also continue to research to improve technology, in order to improve the efficiency and quality of biogas, contributing to reducing greenhouse effects and bringing practical economic benefits.

The invention of Dr. Nguyen Tuan Minh et al. refers to a biogas cleaning device, in which biogas generated from an anaerobic decomposition system is continuously cleaned on a high-performance centrifugal device. In particular, the biogas cleaning device consists of a fixed part and a moving part, in which, the moving part is arranged inside the housing so that the axis of rotation of the lower disc penetrates the first vent, and is connected and driven by an electric motor through a gear reducer, between the rotating shaft and the housing is air-sealed thanks to sealing gaskets. The sorbent solution tank of the device is equipped with an agitator, whose sorbent inlet pipe is connected to the outlet of the apparatus. With this design, after the biogas is passed through the pipe, the pump will spray the absorbed solution into the tube and rotate to cause the droplets to move centrifugally and disperse into the steel foil. As a result, the droplets of KOH solution will come into contact with biogas from the outside and react to absorb impurities such as H2S, CO2, thereby cleaning the gas stream. Dr. Minh added: "The team also installed sensors to check the pH of the adsorbent solution and make it easy to operate automatically."

The advantage of this invention is to thoroughly treat the H2S, CO and CO2 gasses contained in KHS to create a clean gas mixture that meets the standards for generator running. The device using salt gabions is set up to control fully automatically, removing salt deposits from the absorbent solution to ensure the concentration of the absorbent solution and easy to remove. In addition, the equipment uses KOH absorbent solution, so the waste product after the process is a solution including K2S, K2CO3 will be added to the production of organic fertilizer without having to be disposed of as using other absorbent solutions.

Biogas Cleaning Equipment of the Institute of Environmental Technology

To test the practical effect, the research team coordinated and installed an anaerobic sludge decomposition system to recover biogas to burn electricity generation at Saigon – Mien Central Beer Joint Stock Company in Buon Ma Thuot city, Dak Lak. The results showed that the gas samples, after cleaning completely, did not contain H2S; CO and CO2 are also partially treated by interacting with the absorbent solution and meet the standards for running generators.

Translated by Phuong Ha
Link to Vietnamese version

Related news