Products and Technologies

Diesel Particulate Filters (DPF)

Emissions legislation is becoming more stringent. The plumes of black exhaust smoke often visible from older diesel vehicles are the product of a range of exhaust gases containing diesel exhaust particulates, or soot particles. As a result, many diesel engines require the addition of a diesel particulate filter (DPF) to comply with new emissions legislation. A diesel particulate filter eliminates almost all soot particulates from the exhaust gases by burning them within: between 85%-100% of the soot is removed from the system. A diesel-powered vehicle equipped with a properly-functioning diesel particulate filter will emit no visible smoke from its exhaust tailpipe.

Our DPF-solutions look similar to a common exhaust silencer and are preferable mounted close to the engine. Inside the particulate filter, the sophisticated alloy foam structure is designed to filter the exhaust gases while minimizing flow restriction, thereby maintaining full engine performance. The exhaust gas flows through the foam and the particulate matters deposit on the filter material.

Any filter has a finite capacity, so diesel particulate filters must be cleaned out to avoid blocking. An overfilled filter causes excessive exhaust backpressure - this can damage or destroy the engine and the DPF itself. When the diesel particulate filter is becoming loaded, either passive or active regeneration is necessary to remove the accumulated soot from the filter – see Regeneration.

Diesel Oxidation Catalyst (DOC)

Unlike a DPF, which cleans exhaust gas by forcing the gas to flow through the filter, a catalytic converter is a flow-through device which cleans gases as they pass through a vehicles exhaust systems. Inside the catalytic converter, a catalyst initiates a chemical reaction to convert noxious by-products of combustion to less toxic substances. The specific catalyzed chemical reactions vary with the type of catalytic converter, e.g. Diesel Oxidation Catalyst (DOC). Combinations with Diesel Oxidation Catalyst and Particle Oxidation Catalyst (POC) are possible too.

Catalytic converters typically consist of a catalyst core or substrate, a washcoat, and the catalyst itself, most often a precious metal.

Selective Catalytic Reduction (SCR)

Selective catalytic reduction (SCR) is one of the most fuel-efficient and cost-effective diesel engine emissions control technologies available for tackling nitrogen oxide (NOx). A SCR can be used to combat NOx from passenger car diesel engines up to large ship diesel engines, even gas turbines.

The SCR technology reduces levels of NOx using ammonia as a reductant within a catalyst system. The reducing agent reacts with NOx to convert the pollutants into nitrogen and water, with a performance up to 90%.