Small-scale Biogas Upgrading: Green Gas with DMT’s Carborex® MS
Author: Lems, R. and Dirkse E.H.M.
Keywords: Carborex-MS, CHP, Biogas, Bio-methane, CBG, Car fuel, Gas separation, Green gas, Gas Membrane, Small
Abstract: More and more effort is being put in the utilization of bio-solids. Bio-solids can be an important source for useful products like fertilizers and biogas. DMT has been developing biogas treatment plants for over 20 years following the market developments closely.
Biogas was first seen as a nuisance (e.g. landfills, creating odor problems and methane emissions). A flare has always been a cheap and simple solution. But with time, more and more biogas was produced intentional from bio-solids to generate energy.
In the current market, the choice for utilization of the biogas is usually a choice for a single technology (e.g. boiler, CHP or upgrading to natural gas/ fuel quality), which is than fixed for the next 10-20 years. At the same time economical feasibility, especially for biogas upgrading, but also the other technologies, is based on “the bigger the better” principle, which is relying on the benefit of scale. This is in contrast to the reality where the biggest potential for biogas production is on small-scale sites.
DMT has developed a biogas upgrading plant with the focus on small-scale utilization of bio-solids. In this article it is shown that, also with a biogas production of only 50-200Nm3/h, it is feasible to utilize biogas as a combination of energy sources. The DMT Carborex MS® is a modular plant built in a container. The biogas upgrading is performed with gas selective membranes. The upgraded gas with a methane concentration of 96-98% CH4 can be used in the local gas grid, or can be further compressed to 220 bar and used as vehicle fuel (CBG). To optimize the energy balance and to prevent methane emissions, the off-gas from the membranes is burned in a micro-turbine, to produce electricity and heat.
Read the article here.