BioSiv
From Biogas to Bio-Methane by Vacuum-Pressure-Swing-Adsorption
For the methane production from biogas a special 6 adsorber process was developed by BIOSIV.
With this unique process it is possible
to reduce the CO2-content even down to ppm range at a low energy consumption.
For this process an adsorbent is used wich allows the separation of gases due to the different kinetics, that means the different velocity of adsorption. Due to the specific pore diameter of the adsorbent, smaller molecules like CO2 or O2 are adsorbed fast. CH4 is a larger molecule that is adsorbed but very slow. The adsorption time therefore has to be optimized, not to long and not to short. On the contrary the longer the desorption time, the better the desorption and the loading capacity. A special step diagram and the use of two independent vacuum pumps results in a longer vacuum phase in compared to conventional VPSA-systems. An additional advantage is the sophisticated valve system as it is shown in the above diagram. A patented system with a single control valve per adsorber vessel ensures a smooth and effective operation of the system.