A researcher from Technical University of Denmark (DTU) has collaborated with MAN Diesel & Turbo to develop a new software that can help ship owners and operators reduce nitrogen oxide (NOx) and black smoke emissions from their vessels.
The software is expected to be implemented on MAN Diesel's new marine engines by the end of the year, and is intended to enable the marine industry to more easily comply with the International Maritime Organisation’s (IMO) Tier III NOx standards.
IMO's new regulations require any marine diesel engine installed on a ship that was constructed on or after 1 January 2016, and operating in the North American Emission Control Area (ECA) and the US Caribbean Sea ECA, to significantly reduce its NOx emissions.
The new software has been developed by KrænVodder Nielsen and uses EGR technology, which facilitates recirculation of part of the exhaust gas to the ship engine to help limit NOx emissions.
The recirculation takes place with the optimum quantity of exhaust to reduce the formation of NOx, while also ensuring there is sufficient oxygen to combust the fuel. This process prevents black smoke from forming when the ship accelerates or slows down.
Nielsen said: “However, marine engines are very different. Sometimes they are two-stroke engines and not four-stroke engines, so it was not possible to just copy the approach from car engines. I focused instead on developing a new method that is better suited to marine engines.
“I found out that the academic methods for development of the control of a marine engine with EGR technology at that time were too complex. Therefore, it quickly became clear to me that I had to develop a simple model that includes only the critical part of the system that we wanted to improve.
“From there, we developed a new control that coordinates the recirculation and fuel injection without requiring too much tuning of other parts of the system.”
The technology developed by Nielsen has already been tested on a range of marine engines during its development phase.
Image: New software developed to help reduce nitrogen oxides emission from ship. Photo: courtesy of MAN Diesel & Turbo / Technical University of Denmark (DTU).