In 2013 just under $26 billion will be spent to remove carbon monoxide, volatile organic compounds and particulate carbon from stationary and mobile sources. Ninety-two percent of the market purchases will be for mobile sources. This is the conclusion reached in Thermal/Catalytic World Air Pollution Markets published by the McIlvaine Company. (www.mcilvainecompany.com)
Gasoline fueled vehicles typically use a 3-way catalyst (TWC) to convert three pollutants: carbon monoxide (CO), hydrocarbons (HC) and oxides of nitrogen (NOx) to carbon dioxide (CO2), water (H2O) and nitrogen (N2).
Diesel-fueled vehicles use a diesel oxidation catalyst (DOC), which uses oxygen (O2) in the exhaust gas stream to convert carbon monoxide to CO2 and hydrocarbons to H2O and CO2. These converters often operate at 90 percent efficiency, virtually eliminating diesel odor and helping to reduce visible particulates (soot). A DOC can reduce particulate matter (PM) by up to 50 percent, but more effective PM removal may be required and is achieved with diesel particulate filters (DPF). NOx emissions are more challenging, with selective catalytic reduction (SCR) and NOx traps (or NOx Absorbers) as the two main removal techniques used. NOx removal treatment is analyzed in a separate report.
Diesel particulate filters remove particulate matter found in diesel exhaust by filtering exhaust from the engine. The filters are commonly made from ceramic materials such as cordierite, aluminum titanate, mullite or silicon carbide. To ensure that particulates are oxidized at a sufficient rate, the filter must operate at a sufficient temperature and with oxidizing gases, which can be supplied by the exhaust gas stream in some systems. This filter is referred to as the ‘passive’ filter, and regenerates continuously during the regular operation of the engine. Passive filters usually incorporate some form of a catalyst.
Sales of emission control systems are being driven by increased regulations. European standards are setting the pace for the world, and many countries have adopted these or similar standards. Low Emissions Zones are progressively implemented in many urban areas in Europe and these request diesel vehicles to meet a satisfactory level of exhaust emissions before they are allowed to drive inside the zone. In the state of California, the California Air Resources Board has mandated that all Class 7 and Class 8 heavy diesel trucks meet certain emission targets by 2016, with interim targets established for 2011, 2012 and 2013 such that 90 percent of current operating diesel trucks will be required to meet these targets by 2014.
The industrial market for thermal treatment not including flares will be just under $1.9 billion in 2013.
The biggest investment will be for regenerative thermal oxidizers (RTO). Regenerative catalytic oxidizers were once thought to be an important development, but have never met expectations. Direct thermal is used where there is ample fuel value in the gas being treated. Catalytic oxidation is used where there is enough fuel value that combustion will take place in the presence of a catalyst. The regenerative thermal approach is used where there is a low fuel value and it is important to recapture the heat of combustion in order minimize fuel consumption.
For more information on: Thermal/Catalytic World Air Pollution Markets, click on: http://www.mcilvainecompany.com/brochures/air.html#n007.