Every Alternative.

Three-Way Catalyst for Emissions Control.

Three-Way CatalystThe Cummins Westport (CWI) ISL G natural gas engine uses Stoichiometric Combustion with cooled gas exhaust recirculation (EGR) and a Three-Way Catalyst (TWC). The ISL G is the first of the CWI products to use a TWC for emissions control. The B and C series engines utilize lean burn technology and an oxidation catalyst.

Stoichiometric combustion with cooled EGR creates the ideal combustion process with the chemically correct mixing of fuel and air, offering increased power density and thermal efficiency. It reduces in-cylinder combustion temperatures and creates an oxygen-free exhaust, which then enables the use of a TWC for nitrogen oxide (NOx) control.

What is a TWC?

A TWC is a simple, maintenance-free device that reduces three harmful emissions: hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxide (NOx). The end products are: water (H2O), carbon dioxide (CO2), and nitrogen (N). A TWC is packaged as a replacement muffler and gives consistent performance across all duty cycles.

inlet three-way catalyst outlet
NOx

CO

HC

© DCL International Inc.
N2

CO2

H2O

Benefits of using a TWC

The ISL G with a TWC requires no diesel particulate filter (DPF) or selective catalytic reduction (SCR). It meets 2010 EPA and CARB emissions standards today, and is maintenance-free.