Novel Fluropolymer Membrane for the Separation of Carbon Dioxide from Methane in Biogas Digestors

Separating carbon dioxide from methane is a key challenge for the renewable gas industry. Biogas is produced largely on farms or small waste centers, not at large centralized plants. While there are existing technologies to separate methane from carbon dioxide, they require multiple stage high pressure, and are sensitive to process poisons. An efficient and cost effective solution is needed to bring down barriers that previously prevented small scale operations from transforming their biogas into usable fuel. CMS has developed a membrane aimed at allowing users to capture, separate and upgrade existing biogas streams that would otherwise be lost or under-valued.

Designed to operate at low pressure while maintaining high selectivity(>20) and permeance, Optiperm^TMbiogas has demonstrated promising performance in laboratory testing. Optipermâ„¢ biogas is stable in the presence of water and hydrogen sulfide, requiring less pretreatment. Initial laboratory tests show that the membrane is stable in feeds with up to 100% humidity and 300ppm of hydrogen sulfide.

Results from the first field demonstration of Optipermâ„¢ biogas will be shared. Working with Energy Projects Manager Matt Steiman at the Dickinson College Farm, a small spiral wound module system has been installed. The system takes raw biogas feed directly from the digester with no pretreatment. The pilot is intended to demonstrate successful operation under field conditions for an extended period of time. Optiperm^TMbiogas technology will be tested for a period of at least 2 months to demonstrate stability in the field and validate performance measured in the CMS laboratory. Optiperm^TMbiogas upgrading streams from 60% to 90% methane in a single stage.