Biogas from anaerobic digestion is one of the most well-established renewable energy sources. Improvements in biogas technology are achievable through the production of biomethane, an upgrading that requires the development of processes aimed at effectively storing and refining biogas. Although carbon dioxide is the major contaminant in the raw biogas during the production of biomethane, it has been shown that the removal of hydrogen sulfide and other minor pollutants can be of crucial importance for the technological and economic feasibility of the whole gas upgrading chain. The application of hydrate-based technologies to biogas upgrading has been poorly investigated and limited to the separation of CH4/CO2 mixtures. In addition, different interpretations can be found in literature. In the present paper, a hydrate-based process was used to carry out tests on the upgrading of biogas mixture in order to assess the effective practicability of such method for this purpose. The experimental apparatus consists of a high-pressure cylindrical stainless steel vessel with a total internal volume of 25 l. It was used in previous works for methane and carbon dioxide hydrate formation processes. The objective of the investigation is to evaluate the selectivity and the separation efficiency of the process and the role of hydrogen sulphide in the hydrate equilibrium.
Purification of biomethane from biogas through hydrate-based technology
CASTELLANI, BEATRICE;ROSSI, Federico;NICOLINI, ANDREA;FILIPPONI, MIRKO;MORINI, ELENA;COTANA, Franco
2014
Abstract
Biogas from anaerobic digestion is one of the most well-established renewable energy sources. Improvements in biogas technology are achievable through the production of biomethane, an upgrading that requires the development of processes aimed at effectively storing and refining biogas. Although carbon dioxide is the major contaminant in the raw biogas during the production of biomethane, it has been shown that the removal of hydrogen sulfide and other minor pollutants can be of crucial importance for the technological and economic feasibility of the whole gas upgrading chain. The application of hydrate-based technologies to biogas upgrading has been poorly investigated and limited to the separation of CH4/CO2 mixtures. In addition, different interpretations can be found in literature. In the present paper, a hydrate-based process was used to carry out tests on the upgrading of biogas mixture in order to assess the effective practicability of such method for this purpose. The experimental apparatus consists of a high-pressure cylindrical stainless steel vessel with a total internal volume of 25 l. It was used in previous works for methane and carbon dioxide hydrate formation processes. The objective of the investigation is to evaluate the selectivity and the separation efficiency of the process and the role of hydrogen sulphide in the hydrate equilibrium.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
