The Process for Biogas Upgrading:
The SGI-PSA process for upgrading of raw biogas to bio natural gas quality applies a Vacuum regenerated Pressure Swing Adsorption (PSA) technology. CO2, higher CxHy,H2S, odours and other undesired components will be simultaneously removed by activated carbon and carbon molecular sieves. A methane purity of >96%Vol as well as methane recoveries of 98% can be achieved. The SGI - PSA CO2 removal plants are providing low-cost bio natural gas with a reliable, flexible and trouble free process. SGI - PSA systems and machinery components for feed gas compression and vacuum generation are successfully employed for the bulk removal of CO2 from various raw gases. The useful capacities range from several 100 Nm3/h bio natural gas product up to several 1000 Nm3/h.



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Special Features

Particular features of SGI's PSA process and machinery components are high CH4 recovery rates, low operating and maintenance costs and operational simplicity. Extensive know-how and engineering expertise guarantee the design and construction of tailor-made and economical plants of the highest quality. Modular, containerized design of the CO2 removal plants reduces erection time and costs at site. The fully prefabricated machinery containers are thoroughly tested before they leave SGI's workshop.


The Advantages

  • High CH4-Recovery > 98%
  • High CH4-purity > 96%Vol
  • High bio natural gas quality
  • Partial removal of N2 and O2
  • Low energy for dry running machinery up to
    ≤ 0,17 kWh/Nm3 for feed gas ≥ 800Nm3/h and
    ≤ 0,20 kWh/Nm3 for feed gas ≤ 800 Nm3/h
  • Dry process without oil contaminations
  • No use of chemicals
  • Low corrosion
  • Less maintenance
  • Reliable and flexible process
  • Fully automatic operation
  • Competitive investment cost
  • Containerized design


Process Flow Diagram of SGI Biogas CO2 Removal PSA Process


SGI - Biogas - PSA

  • High efficiency
  • Long maintenance free operation
  • Base frame installation
  • Automatic start and stop in every operating position
  • Automatic adjusting process in accordance to feed gas quantity and quality
  • Low maintenance costs


SGI - Dry Rotating Machinery

  • Dry and oil-free gas compression and evacuation
  • Non-contacting rotating  type
  • Long maintenance free operation
  • Special seal gas system
  • Base frame installation
  • Frequency controlled motor
  • Air cooled system
  • Low energy consumption
  • Low maintenance costs


SGI - Machinery Container

SGI - Biogas - PSA and Multi Stage Machinery Container for:

  • Biogas - PSA
  • Dry and oil-free gas compression and evacuation

Advantage of machine container installation

  • No need for a special machine foundation, only a concrete base plate is required  for the machine container
  • No need for a noise protected and ventilated machine house or building
  • The PSA and the machinery  is completely installed and piped in the machine container
  • The machines are installed inside the container on flexible machine  elements so that no dynamic machine forces are transferred to the concrete base plate
  • Wiring of PSA machines and instrumentation to a terminal box inside the machine container
  • Noise protection of the machine container wall down to 80 dB(A)pressure sound level in 1 m distance from outside container wall
  • Ventilation inside the container to transfer the radiated machine heat via the ventilation air outside the container including inlet and outlet noise elimination  houses
  • Short installation time because  PSA and machinery inside container is completely mounted, piped, instrumented, wired and tested.


 Container installed machinery fully assembled and tested, ready for start-up.