Upgrade of methane from landfill gas by PSA

• Type: Article in International Scientific Journal
• Date: 2005

Authors

Simone Cavenati (Author) FEUP; Carlos Grande (Author) FEUP; Alírio Rodrigues (Author) FEUP

Journal

Title: Energy & Fuels

Vol. 19 No. 6

Pages: 2545-2555

ISSN: 0887-0624

Publisher: American Chemical Society

Indexing

ISI Proceedings

Scientific classification

CORDIS: Technological sciences > Engineering > Chemical engineering

Other information

Resumo (PT): This work focuses on the production of pipeline grade methane from landfill gas (LFG). Vacuum pressure swing adsorption technology using a kinetic adsorbent, Carbon Molecular Sieve 3K (Takeda), was employed for the separation of methane-carbon dioxide mixture. Adsorption equilibrium and kinetics of methane and carbon dioxide are reported at 298, 308, and 323 to model the adsorption-based process. A four-step Skarstrom-type cycle was employed comprising pressurization, feed, counter-current blowdown, and counter-current purge with product. Co-current pressurization with feed stream and counter-current pressurization with product were evaluated. The separation of a mixture of CH4 (55%)-CO2 (45%) was tested using two different four-step cycles: pressurization with feed stream, feed, blowdown, and purge with product and pressurization with product, feed, blowdown, and purge with product. The results indicate that purity of methane higher than 96% can be obtained with recovery higher than 75%. The difference of the performance in the non-adiabatic and adiabatic cases was also studied. It was observed that the temperature in the column increases allowing a faster and more important desorption of carbon dioxide in the blowdown step, retaining more CO2 in the column and improving methane purity and recovery.

Abstract (EN): This work focuses on the production of pipeline grade methane from landfill gas (LFG). Vacuum pressure swing adsorption technology using a kinetic adsorbent, Carbon Molecular Sieve 3K (Takeda), was employed for the separation of methane-carbon dioxide mixture. Adsorption equilibrium and kinetics of methane and carbon dioxide are reported at 298, 308, and 323 to model the adsorption-based process. A four-step Skarstrom-type cycle was employed comprising pressurization, feed, counter-current blowdown, and counter-current purge with product. Co-current pressurization with feed stream and counter-current pressurization with product were evaluated. The separation of a mixture of CH4 (55%)-CO2 (45%) was tested using two different four-step cycles: pressurization with feed stream, feed, blowdown, and purge with product and pressurization with product, feed, blowdown, and purge with product. The results indicate that purity of methane higher than 96% can be obtained with recovery higher than 75%. The difference of the performance in the non-adiabatic and adiabatic cases was also studied. It was observed that the temperature in the column increases allowing a faster and more important desorption of carbon dioxide in the blowdown step, retaining more CO2 in the column and improving methane purity and recovery.

Language: Portuguese

Type (Professor's evaluation): Scientific