C-Capture Biogas Upgrading GSU Technology

C-Capture Gas Sweetening and Upgrading (GSU)

  • There are a number of areas where removal of CO2 from gas streams is important, and the versatility of the C-Capture technology means that it can be adapted for a broad range of such applications.
  • Methane, the main component of natural gas and biogas, is usually produced containing large amounts of CO2, which greatly reduces its potential for combustion, and also gives high variability which is unacceptable for many applications.
  • For natural gas, removal of CO2 and other impurities is referred to as sweetening, whereas for biogas it is called upgrading.
  • The principles behind C-Capture GSU technology are similar to those for C-Capture CCS, but there are also significant differences.
  • For GSU compared to CCS, scales required are more moderate, levels of CO2 in the gas stream are higher, and the most important impurity is H2S, rather than SOx and NOx.
  • The capture solvent selectively reacts with CO2 and H2S and allows unreactive methane to pass through. The solvent loaded with CO2 is then heated, liberating CO2 and hence regenerated for reuse in a continuous process.
  • Current approaches for CO2 removal are amine-based, and have significant issues with energy requirements and corrosion. The C-Capture GSU technology offers an effective, low energy alternative, operating at low temperatures and with low corrosivity, such that relatively inexpensive materials and methods of construction can be used.


The concentration of CO2in the Earth’s atmosphere is now over 400 ppm (0.040%) by volume, rising from a pre-industrial maximum of around 300 ppm.
Drax power station (4000MW, ca. 7% UK supply) produces up to 50,000 tonnes CO2 per day.
A 750ml bottle of Champagne has a typical pressure of over 5 times atmospheric pressure and contains the equivalent of over 4 litres of CO2 under normal conditions
The body produces approximately 1 kg of CO2per day per person, which equates to almost 29,000 kg of CO2 per person over a typical lifetime
CO2 extinguishes flames, and some fire extinguishers, especially those designed for electrical fires, contain liquid CO2 under pressure.
A children’s sweet called Pop Rocks is pressurised with CO2 gas at about 40 bar (580 psi). When placed in the mouth, it dissolves (just like other hard sweets) and releases the gas bubbles with an audible pop.
Human activities such as the combustion of fossil fuels and deforestation have caused the atmospheric concentration of CO2 to increase by about 35% since the beginning of the age of industrialization.
CO2 is an end product in organisms that obtain energy from breaking down sugars, fats and amino acids with oxygen as part of their metabolism.
Photosynthesis uses CO2and water to produce sugars and occasionally other organic compounds, releasing oxygen as a waste product.
Plants can grow up to 50% faster in concentrations of 1,000 ppm CO2 when compared with ambient conditions.
Sources: beekmanwine.com and wikipedia.org