Air Clean is a company specialising in environmental rehabilitation of polluted air streams, primarily from industrial emissions, waste water and solid waste treatment processes.
Air Clean operates on a worldwide basis, offering the full range of air treatment technologies including; biological, chemical and physical technologies.
Air Clean is a fully integrated company performing all of the production functions in-house including design, manufacture, assembly, installation and final testing.
Access to the latest technology coupled with continuous research and collaboration with Universities and Key Partners ensures Air Clean provide the optimum solution for each individual application by using stand alone or multi – stage technologies (systems integration).
The partnership with Anua Clean Air International ensures Air Clean can offer best in class, patented, MónaShell®, MónaFil® and now the new CrumRubber™ bio-technologies for the treatment of municipal and industrial odour including VOC emissions.
Anua Clean Air International Ltd is a new trading company which is incorporated in Ireland. The company acquired Bord na Móna MónaShell® and MónaFil® brands and the associated patent portfolio for these and new emerging technologies. The company is uniquely positioned to provide back-up and after sales service including technical support, replacement media, system upgrades and new skid mounted or site erected MónaShell®, MónaFil® and CrumRubber™ systems.
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. The Sulphate 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 successfuland this was attributed to the hydrophobic nature of the media. The concept was patented as a roughing process for reduction of H2S prior to biological filters. This allowed for reduced contact times and improved performance with the biological filter.
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 on a high strength airstream containing continuously high levels of H2S (between 200ppm and 400ppm). The initial work in the early 2000’’s demonstrated the crumb rubber media had an excellent affinity for capture of H2S and conversion to sulphate. However early attempts to establish a biofilm on the surface of the media were not successful. Pilot work recommenced in 2009 and ran for three years on an airstream extracted from a transfer point on an industrial waste water anaerobic digester. The initial focus was on establishing conditions under which an attached growth biofilm could form on the surface of the media. Over a three year period critical parameters were optimised and a means of developing an active biofilm on the surface of the media was perfected with this important media. Treatment efficiencies in excess of 98% was achieved on levels up to and in excess of 400ppm. Following successful process development and optimisation the plant was operated for an 18 month period. The airstream that was being piloted had lower oxygen levels and higher carbon dioxide levels that ambient air. This was due to the anaerobic digestion process. Based on the excellent performance of the system and the likely hood that CrumRubber™ had an affinity for volatile siloxanes the next logical step was to adopt the process for biogas and landfill gas treatment.
In 2012 Bord na Mona having installed gas engines on its own landfill experience issues arising from excessively high levels of H2S and volatile siloxanes. This presented an ideal opportunity to trial the CrumRubber™ on a difficult landfill gas application, arising from this a trial was set up in 2013/2014 on what would be classified as a very difficult landfill gas application. Success on this would demonstrate the technology would have also have application on Biogas streams which are very similar in make in general terms H2S levels on Biogas streams from municipal sludge anaerobic digesters would have much lower H2S levels. A three stage 1 m3 pilot plant was designed and build and a successful trials were carried out over a twelve month period on the Landfill gas using a variation of the CrumRubber™ biotrickling technology. Landfill gas H2S Levels in excess of 2000 ppm (peak 4000 ppm) were successful treated during the trial. The data from the trial was used to scale up the technology to treat the full landfill gas stream prior to combustion in the gas engines. These units were manufactured and installed in 2015 and commissioned in Autumn 2015. The units have been in operation for over 12 months successfully removing H2S. What has been noticeable since the start up is that in addition to the removal of H2S the units have also been successful in removing the larger volatile siloxane compounds. This combination has increased engine availability, increased oil change and decoking intervals on the engine and reduced reliance and costs associated with frequent activated carbon change outs.
The application was characterised by the exceptionally high levels of H2S given the technologies ability to cope with such high H2S levels, the affinity CrumRubber™ has for Volatile Siloxanes, and the low operating cost when compared to more conventional technologies. It is clear that CrumRubber™ will have a big future in enabling energy recovery in the form of clean biogas and landfill gas in the resource recovery sector.
A number of new patent applications have been lodged worldwide covering the use of the technology on high H2S air treatment and on Biogas and Landfill gas applications. The first of this type of installation is currently being installed on a high H2S airstream on a municipal waste water application in the middle east.
