How do the different Bright Biomethane’s Carbon Clean® filters work?
Bright Biomethane uses a specially impregnated activated carbon type in the form of pellets for the removal of toxic H2S. This special carbon has the strong property that it takes longer for the carbon to be saturated with H2S. The carbon has an adsorption capacity of 60% of its own weight. For regular carbon this is around 40%. As a result, it takes longer for the special carbon to be refilled so it is more economical to use. Since the H2S in biogas can be present in relatively large quantities (up to 1,000 ppm), the activated carbon must be replaced from time to time when it is saturated. The PurePacs systems from Bright contain two active H2S carbon filters that work independently of each other. At the time of changing the saturated carbon, the installation can still work and produce biomethane.
For the removal of volatile organic compounds, Bright Biomethane uses carbon in the form of so-called granules. This type of carbon is very suitable for removing VOC from the biogas. Since there is less VOC in the biogas than H2S, only one filter is needed for this.