BioMem – the key technology for biomethane in natural gas quality
On the way from biogas to biomethane of natural gas quality, the raw gas is first compressed to 10 – 16 bar using a high-pressure compressor.
The waste heat from the compression process can be made available for extraction via a heat exchanger. The compression stage is followed by a drying stage with temperature control and an activated carbon filter.
The next step is the most important one: the separation of CO2 and water vapor using highly selective hollow fiber membranes. This is based on the different permeabilities (migration speeds) of gases in polymers.
The SEPURAN® Green membrane module from Evonik is the innovative heart of the plant.
Ideal if only a portion of a biogas plant's output is to be extracted and processed into biomethane. The offgas is then recycled and added to the mix, and the downstream CHP plant can easily compensate for the reduced methane concentration; efficiency decreases only minimally.
The operation of Bio CNG filling stations – even in intermittent operation – is the primary area of application for this process.
Picture: Gas processing plant of Gastechnik Himmel
Here, the highly selective membrane modules are arranged in such a way that both product gas and off-gas are concentrated several times.
In this way, a methane slip of less than 0.5 % can be achieved.
This concept ensures the highest possible methane yield while simultaneously ensuring the lowest emissions.
The components for desulfurization, compression, condensation, filtration, and gas separation can be delivered assembled in closed containers. The modular design makes adaptation to any desired plant size possible and cost-effective.
The plant is being built in cooperation with GT-Himmel at the Korneuburg site near Vienna.
The system leaves our factory in a modular design, fully pre-assembled, pre-built, tested and TÜV-approved.
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