An ammonia supplying system using ammonium salt to reduce the NO_x emissions of a 1.1 MW marine engine

AbstractA solid-SCR (selective catalytic reduction) system using ammonium carbamate (AC) was designed to improve NOx emission reduction efficiency and compensate for the shortcoming of the UWS (urea water solution)-SCR system applied to marine diesel engines. The solid-SCR system was installed on the exhaust line of a 1.1 MW engine for electric power generation in a ship, and its performance of emissions reduction was compared with the existing UWS-SCR system. The NOx emitted from the engine was 9.2 g/kWh, and it is reduced to 1.94 g/kWh when using the UWS-SCR system. Using the solid-SCR system significantly lowered NOx emissions to 0.3 g/kWh, which was 15% of the UWS-SCR system. In addition, the solid-SCR system showed fewer ammonia slip characteristics than the UWS-SCR system. In the solid-SCR system, gaseous ammonia was directly supplied in the exhaust line, and it mixed well with the exhaust gas and reacted well with NOx in the SCR catalyst. An endurance test of the solid-SCR system was conducted for 210 h during actual ship operation. The NOx reducing efficiency was maintained at higher than 90% for 210 h. The AC consumption rate was 1.7–4.3 kg/h for the endurance test.KEYWORDS: Ammonium carbamateammoniaSCR (selective catalytic reaction)marine engineNOx AcknowledgmentsSang-Hee Woo helped with data curation, investigated the data and wrote the original draft. Hassan Raza, Won-Mo Kang, Sang Bom Choe, Myeong Hwan Im, Kyung-Sun Lim, Jeong-Gil Nam devised the methodology and experiment and helped with data curation. Hongsuk Kim conceptualised the data, wrote, reviewed and edited the article and supervised the work.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThe authors acknowledge the funding from the Ministry of Science and ICT [grant number 2019M1A2A210385421] under the project ‘Development of electrostatic filtration systems for removal of fine particulate matters from off-road large diesel engines and their field tests for ships.’Notes on contributorsSang-Hee WooDr. Sang-Hee Woo is a Senior engineer at Korea Institute of Machinery and Materials. He graduated in the application of mechanical engineering from the Hanyang University in Republic of Korea, and he obtained his doctor’s degree from the Hanyang University with a thesis entitled Dust Collector Installed at Train Bottom for Removing Particles in Subway Tunnel. His current research focuses on post-treatment of ICEV engine and non-exhaust particle emission.Hassan RazaHassan Raza is a Ph.D. student of Mechanical Engineering at the University of Science and Technology, Republic of Korea, and working as a research assistant in Korea Institute of Machinery and Materials. He received a B.E. in mechanical engineering from the University of Engineering and Technology, Lahore, Pakistan in 2017 with a distinction of Gold Medal. His research interests and activities as a researcher include environment-friendly vehicles and exhaust gas after-treatment systems of IC engines.Won-Mo KangWon-Mo Kang is a Ph.D. student in Department of Environment Energy Machinery at University of Science & Technology in Republic of Korea, and he is doing research at Korea Institute of Machinery and Materials. He obtained his Master’s degree from the University of Science & Technology with a thesis entitled ‘A Study on Low-Temperature NOx Conversion by O3 feed in Automotive Diesel Engines Equipped with Cu-Zeolite SCR Catalyst’. His current research focuses on NOx reduction at low temperature.Sang Bom ChoeSang Bum Choe is an assistant professor at Mokpo Maritime University. He graduated in Mokpo Maritime University in Republic of Korea, and he obtained his Ph.D. degree from the Mokpo Maritime University. His current research focuses on fluid dynamics and flow visualisation.Myeong Hwan ImMyung Hwan Im is an associate professor at Mokpo Maritime University. He graduated in the Mokpo Maritime University in Republic of Korea, and he obtained his Ph.D. degree from the Mokpo Maritime University. He is interested in ship engine and material strength.Kyung Sun LimKyung-Sun Lim is an engineer of T/S Segero at Mokpo Maritime University. He graduated in the application of maritime engineering from the Mokpo Maritime University in Republic of Korea, and he obtained his Master’s degree from the Mokpo Maritime University with a thesis entitled an experimental study on the analysis for shape modification and collection efficiency of small oil boom in channel. His current research focuses on NOx reduction of Diesel Engine and Cavitation of Propeller.Jeong Gil NamProf. Jeong-Gil Nam is a professor at Mokpo Maritime University, Division of Marine Engineering in Mokpo, Republic of Korea. He obtained his doctor’s degree from the Korea Maritime University. He is interested in development of emission reduction system from diesel engines.Hongsuk KimDr. Hongsuk Kim is a Principal engineer at Korea Institute of Machinery and Materials. He got his PhD degree from Sungkyunkwan Univ. in 2003. His major research area is emissions of ICEV engine. He has been published many perpers on emission reduction systems.