SCR system tests conducted

Sea trials, training and scholarship program designed to educate students on clean air technologies.

Image credit:

Updated on 18 Aug 2015 10:41 GMT

Tenneco Inc., a supplier of clean air aftertreatment technologies, is helping engineering midshipmen at the Texas A&M Maritime Academy - part of Texas A&M University in Galveston, United States - to learn first hand how advanced aftertreatment technology can help diesel engines meet new emissions regulations while efficiently and effectively powering the ships of the future.

Midshipmen received hands-on experience this summer with Tenneco's latest large engine selective catalytic reduction (SCR) diesel aftertreatment technology [pictured] on the vessel TS General Rudder, which is operated by the U.S. academy.

Midshipmen helped conduct field tests during their training cruises in the Gulf of Mexico to demonstrate how the system's form, fit, function and performance capabilities can be integrated into a vessel's engine and control architecture.

"Over the next few years, new vessels similar in size to the General Rudder will be required to meet more stringent EPA emissions regulations," said Timothy Jackson, chief technology officer, Tenneco. "The testing conducted on this ship provides us with important data on the system's performance in real-world ocean conditions and gives midshipmen the opportunity to work with some of the industry's most advanced emissions technologies."


Beginning in May 2015, the midshipmen collected and documented over 1,000 hours of real-time operating data, including exhaust backpressure and temperature monitoring, nitrogen oxide (NOx) conversion efficiency and urea quality and consumption.

Tenneco's SCR system was installed on a 33-year-old 800-horsepower, Tier 0 engine that was operational for the duration of the academy's summer cruise training period. While running the engine through multiple duty cycles during real-time operation of the vessel, emission results collected using telematics demonstrated NOx reduction levels that kept the General Rudder compliant with today's stringent EPA Tier IV marine emission requirements under all operational conditions.

"Transforming a 33-year-old mechanical engine into one that meets current EPA Tier IV marine emissions standards clearly demonstrates the effectiveness of Tenneco's SCR system, and how its modular design can be quickly and easily integrated into any engine architecture," Jackson said.

Tenneco conducted similar tests on a 224-foot training vessel in the Great Lakes in 2014. In a series of validation tests, including the ISO 8178 E2 cycle, when a similar engine was outfitted with Tenneco's SCR system, the engine is said to have met all criteria for IMO Tier III, including NOx.


As part of its commitment to continuing education on clean air technologies, Tenneco announced today that it is also awarding $5,000 in scholarships to marine engineering technology students at the University for the 2015-16 academic year.

"One of the primary objectives of this program is to support education and promote clean air technology," said Jackson. "We're pleased to provide scholarships to deserving midshipmen who demonstrate leadership in the field of marine engineering and who have built a greater understanding of clean air technologies. The engineering midshipmen and crew on board with our SCR system provided us with valuable insight, while validating the ease of use for adoption in the marine industry."

"We're pleased that Tenneco has partnered with us to support the educational needs of our students at the Texas A&M Maritime Academy," said Colonel Richard Mallahan, Deputy Superintendent and Chief of Staff of the academy. "This demonstration project helps our midshipmen build important skills, while learning about various types of critical environmental technologies they are likely to encounter in their future maritime careers."

"Today, corporate support of education is paramount in providing the needed funds to help students achieve excellence," said Rear admiral Robert Smith, Superintendent of the Texas A&M Maritime Academy. "This scholarship will be put to good use giving five deserving midshipmen funds to assist them in their studies."

How it works

Tenneco's SCR aftertreatment system aboard the General Rudder features a complete dosing control solution specifically designed for marine engine applications up to 7,500 kilowatts (kW) or 10,000 horsepower. The system is designed to help large engines meet EPA Tier IV and IMO Tier III regulatory requirements and provide precise and reliable delivery of liquid urea via a proprietary injector design, a precision mechatronic fluid delivery pump and customizable remote monitoring and controls.

Tenneco says the SCR system's modular design enables seamless integration for a broad range of engine sizes and works with electrically or mechanically controlled engines. Tenneco also integrates proprietary mixing devices, multiple catalytic configurations and coatings on its SCR that meet performance requirements dictated by emissions legislation. The system has been validated for durability and all components are said to be easy to maintain and service without the need for special tools.

The fluid delivery system with dosing control software is capable of managing multiple injection points and sensors. The system can support urea flows up to 120 metres, which enables a wide array of installation options. Airless urea injection provides high dosing accuracy and consistency.

The system's unique Human Machine Interface (HMI) can be accessed on the front of the fluid delivery box or remotely via a touch screen tablet. It features an easy-to-use interface to access onboard diagnostic functions and to monitor all system parameters, including but not limited to NOx reduction performance and urea concentration levels in real time.