Wabtec’s marine diesel engine’s EPA T4 / IMO III emissions compliance

Wabtec’s EGR technology delivers EPA T4 / IMO III emissions standards

The adverse impact of air pollutants to human health, particularly NOX, particulate matter and SOX, has triggered emissions regulations in several industry sectors, including the marine sector. Air pollutants in sea going ship’s exhaust gasses are governed by increasingly more stringent emission standards defined in the International Maritime Organization’s Maritime Pollution Convention Annex VI. U.S. flagged ships operating in U.S. waters or in the designated North American and U.S. Caribbean Sea environmental control areas must comply with the emissions limitations defined in the U.S. Code of Federal Regulations, title 40 part 1042, governed by the Environmental Protection Agency.

A common methodology used to meet the IMO III or EPA T4 NOX emission standards is reducing NOX in the exhaust gas through deployment of a Selective Catalytic Reduction (SCR) exhaust gas after-treatment system. An alternative methodology to meet the EPA T4 or IMO III standards is to minimize formation of NOX in-cylinder through deploying Exhaust Gas Recirculation (EGR) technology. In 2015, after 6 years of development, Wabtec Corporation was the first to launch a medium-speed marine diesel engine that is certified to meet the IMO III and EPA T4 standards through an advanced EGR system, while maintaining world class fuel efficiency.

This paper describes Wabtec’s advanced EGR technology and results from independent evaluation studies comparing propulsion configurations based on engines with EGR technology versus those with SCR after-treatment technology on the following aspects: (i) system weight and size; (ii) installation cost; and (iii) operating cost.