New Vehicles and Engines
The most effective way to use catalyst, filter and adsorber technologies is as part of an integrated system on a new vehicle.
This allows the system to be designed as a complete, optimised unit, with the vehicle’s calibration set to give the best performance under each individual operating condition in the ‘map’ contained in the vehicle’s engine control unit (ECU). Exhaust gas aftertreatment technologies can then complement, where appropriate, mechanical measures such as improvements to fuel management and the combustion process.
The technology pages show the range of catalysts, filters and adsorbers that are available. Some are only appropriate for particular types of engines (for instance three-way catalysts are used with gasoline and gas engines) but all can be used in a variety of vehicle and machinery applications.
The range of applications covers small, hand-held equipment such as grass trimmers and chainsaws, road vehicles including motorcycles, cars, delivery vans, trucks and buses, through to construction and agricultural equipment, railway locomotives and ships.
Legislation for passenger cars, commercial vehicles and buses is evolving. The stringent requirements that the vehicles need to comply with regarding pollutant and greenhouse gas emissions have undoubtedly revolutionised the automotive industry, meaning different options are available in the market. As technology continues to be developed, the future of personal and commercial transport will comprise a range of technologies from ‘conventional’ gasoline and diesel to electrified – mild, full or plug-in hybrid – and full electric vehicles.
With greater attention on fuel efficiency and carbon dioxide (CO2) emissions, an increasing number of diesel and gasoline passenger cars are electrified in a ‘mild hybrid’ set-up, with battery technology providing fuel economy benefits, Full hybrid electric vehicles (FHEV), most of which use a gasoline engine along with a battery that is recharged when the brakes are used, have been available in Europe for around 20 years.
Plug-in hybrid electric vehicles (PHEV) are similar to battery electric vehicles (BEVs), but with an internal combustion engine (often a gasoline one) that can take over when the charge in the battery has been used.
Levels of electrification are expected to increase for commercial vehicles and buses, particularly those devoted to urban/regional missions. This can allow further emissions reductions in the medium/long term.
Retrofitting Catalyst Systems
A number of existing vehicles can be retrofitted with catalytic converters, diesel particulate filters (DPFs) and Selective Catalytic Reduction (SCR) systems. Tax reductions or vehicle-use restrictions have provided the incen`tive and diesel retrofit technologies have demonstrated their ability to significantly reduce unwanted emissions at reasonable costs without jeopardising vehicle or machine performance.
A range of aftertreatment technologies – including the necessary fuel and engine controls to make them work reliably – are available for a wide range of heavy-duty vehicles and non-road mobile machinery. Many thousands of trucks and buses have been engineered to reduce particulate or NOx emissions and to meet the latest EU emissions standards by adding a particulate filter or SCR system.