Aftertreatment Technologies

To meet Tier 4 interim/Stage IIIB emissions standards and beyond, Cat aftertreatment components have been designed to match application needs.

For small to medium applications:

• Service-free compact systems
• Passive regeneration
• No supplemental fuel needed

For medium to large applications:

• Durable packaged systems designed to withstand even the most demanding applications
• Fuel-efficient, reliable regeneration
• Operates automatically

Cat aftertreatment components include:

• Diesel Oxidation Catalyst (DOC)
  The DOC uses a chemical process to transform pollutants in the exhaust stream into less harmful components.
  
• Diesel Particulate Filter (DPF)
  A DPF traps additional particulate matter that’s carried in the exhaust stream, preventing it from being released into the atmosphere.
• Passive Regeneration System (C4.4 ACERT, C6.6 ACERT)
  All Cat Tier 4 Interim/Stage IIIB engines use a passive regeneration system that continually regenerates at a slow rate, during normal machine operation, using the heat from the engine’s exhaust gas.
• Cat Regeneration System (C7.1 ACERT –C18 ACERT
  The Cat Regeneration System (CRS), is an active regeneration system used in engines rated130–560 bkW (175–750 bhp) when supplemental regeneration is needed. CRS elevates exhaust gas temperatures to promote oxidation and burn off soot in the DPF.