As part of an extensive research program in the early 2000’s to develop a catalytic roughing filter for H2S removal Bord na Mona identified Crumb Rubber as an ideal media with the capability to catalytically remove and convert H2S to sulphate which deposited on the surface of the crumb rubber media (origin of material waste automobile tyres). The media could be regenerated by continuous or intermittent flushing with water. Typical removal efficiencies for levels from 10 to 200 ppm of H2S ranged from 30 to 70 percent. Initial attempts to get the media to operate as a support media for biological treatment were not successful and this was attributed to the hydrophobic nature of the media. The concept was patented but never fully comericialised.
In 2009 a new research program was commenced to identify an inert recovered biotrickling media for treatment of H2S. The testing of Crumb Rubber on a high strength H2S air stream was resumed. The initial work demonstrated the crumb rubber media had an excellent affinity for capture of H2S and conversion to sulphate. However the media was not ideal for establishing biological activity. Over a three year period critical parameters were optimised and a means of developing successful biological treatment was perfected with this important media. Treatment efficiencies in excess of 98% was achieved on levels up to and in excess of 400ppm. Following this successful trials were carried out on Landfill gas using a variation of this technology. Levels in excess of 2000 ppm were successful treated with this technology on landfill gas. Two separate patents have been applied for on this technology one for treatment of air and one for treatment of landfill gas and biogas. Anua Clean Air International Ltd has acquired the rights to the air cleaning patent and Bord na Mona have retained the rights to the gas cleaning technology.