Evaluation of Emissions Characteristics of Marine Diesel Engine Intake of Exhaust Gas of Lean Burn Gas Engine

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Yoshifuru Nitta ◽  
Dong-Hoon Yoo ◽  
Sumito Nishio ◽  
Yasuhisa Ichikawa ◽  
Koichi Hirata ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Co2 Emissions ◽  
Exhaust Gas Recirculation ◽  
Marine Diesel Engine ◽  
Exhaust Gas ◽  
Lean Burn ◽  
Gas Engine ◽  
Marine Diesel ◽  
Gas Recirculation

The need for reductions of nitrogen oxides (NOx), sulfur oxides (SOx), and carbon dioxide (CO2) emissions has been acknowledged on the global level. However, it is difficult to meet the strengthened emissions regulations by using the conventional marine diesel engines. Therefore, lean burn gas engines have been recently attracting attention in the maritime industry. Because they use natural gas as fuel and can simultaneously reduce both NOx and CO2 emissions. On the other hand, since methane is the main component of natural gas, the slipped methane, which is the unburned methane emitted from the lean burn gas engines, might have a potential impact on global warming. The authors have proposed a combined exhaust gas recirculation (C-EGR) system to reduce the slipped methane from the gas engines and NOx from marine diesel engines by providing the exhaust gas from lean burn gas engine to the intake manifold of the marine diesel engine using a blower. Since the exhaust gas from the gas engine includes slipped methane, this system could reduce both the NOx from the marine diesel engine and the slipped methane from the lean burn gas engine simultaneously. This paper introduces the details of the proposed C-EGR system and presents the experimental results of emissions characteristics on the C-EGR system. As a result, it was confirmed that the C-EGR system attained more than 75% reduction of the slipped methane in the intake gas. Additionally, the NOx emission from the diesel engine decreased with the effect of the exhaust gas recirculation (EGR) system.

Evaluation of Emissions Characteristics by Charging Exhaust Gas From Lean Burn Gas Engine Into Marine Diesel Engine

2016 ◽  
Author(s):  
Yoshifuru Nitta ◽  
Dong-Hoon Yoo ◽  
Sumito Nishio ◽  
Yasuhisa Ichikawa ◽  
Koichi Hirata ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Co2 Emissions ◽  
Diesel Engines ◽  
Marine Diesel Engine ◽  
Exhaust Gas ◽  
Maritime Industry ◽  
Lean Burn ◽  
Gas Engine ◽  
Marine Diesel

Reductions of Nitrogen oxides (NOx), sulphur oxides (SOx) and carbon dioxide (CO2) emissions have been acknowledged on the global level. The International Maritime Organization (IMO) has developed some mandatory or non-mandatory instruments such as codes, amendments, recommendations or guidelines to strengthen the emissions regulations on ships engaged in international voyage. However, it is difficult to meet the strengthened emissions regulations on the conventional marine diesel engines. Lean burn gas engines have been thus recently attracting attention in the maritime industry. The lean burn gas engines use natural gas as fuel and can simultaneously reduce both NOx and CO2 emissions. On the other hand, since methane is the main component of natural gas, the slipped methane which is the unburned methane emitted from the lean burn gas engines might have a potential impact on global warming. The authors investigated on a ship installed conventional marine diesel engines and lean burn gas engines, and have proposed a C-EGR (combined exhaust gas recirculation) system to reduce the slipped methane from the gas engines and NOx from marine diesel engines. This system consists of a marine diesel engine and a lean burn gas engine, and the exhaust gas emitted from the lean burn gas engine is provided to the intake manifold of the marine diesel engine by a blower installed between both engines. Since exhaust gas from the gas engine including slipped methane, this system could reduce both the NOx from the marine diesel engine and the slipped methane from the lean burn gas engine simultaneously. This paper introduces the details of the proposed C-EGR system, and presents the experimental results of emissions and engine performance characteristics on the C-EGR system. In the experiment, the diesel engine was operated at three load conditions of 25, 50 and 75% along with the propeller load curve. In order to keep the slipped methane concentration constant, the gas engine was operated at a constant load condition of 25%. The intake exhaust gas quantity which is supplied to the diesel engine was adjusted by the blower speed. As a result, it was confirmed that the C-EGR system attained more than 75% reduction of the slipped methane in the intake gas. In addition, the NOx emission from the diesel engine decreased with the effect of the EGR system. Also the fuel consumption of the diesel engine did not increase, because of the methane combustion in the intake gas.

Evaluating dedicated exhaust gas recirculation on a stoichiometric industrial natural gas engine

2019 ◽  
pp. 146808741986473 ◽  
Author(s):  
Chris A Van Roekel ◽  
David T Montgomery ◽  
Jaswinder Singh ◽  
Daniel B Olsen
Keyword(s):  
Natural Gas ◽  
Power Density ◽  
Positive Impact ◽  
Exhaust Gas Recirculation ◽  
Exhaust Gas ◽  
Lean Burn ◽  
Gas Engine ◽  
Natural Gas Engine ◽  
Excess Air ◽  
Gas Recirculation

Due to the market presence that natural gas has and is expected to have in the future energy sector, research and development of novel natural gas combustion strategies to increase power density, lower total emissions, and increase overall efficiency is warranted. Dilution whether by excess air or by exhaust gas recirculation has historically been implemented on diesel, natural gas, and gasoline engines to mitigate various regulated emissions. In the large industrial natural gas engine industry, excess air dilution or ultra-lean-burn operation has afforded lean-burn engines increased power density and reduced NO x emissions. This advance in technology has allowed lean-burn engines to compete in markets such as electrical power generation which previously they had not been able. However, natural gas engines utilizing a non-selective catalytic reduction system or three-way catalyst must operate under stoichiometric conditions and thus are limited in power density by exhaust gas temperatures. In previous gasoline small engine research, a novel exhaust gas recirculation technique called dedicated exhaust gas recirculation was shown to have a positive impact on engine-out emissions of NO x and unburned hydrocarbons while also lowering exhaust component temperatures. This work seeks to understand the consequences of implementing a dedicated exhaust gas recirculation system on a multi-cylinder stoichiometric industrial natural gas engine. The results of this initial evaluation demonstrate reductions in engine-out NO x and CO emissions and improvements in engine-out exhaust gas temperatures with the dedicated exhaust gas recirculation technique. However, in a low-turbulence combustion chamber, dedicated exhaust gas recirculation significantly lowers the overall rate of combustion and results in significant differences in cylinder-to-cylinder combustion.

Effects of Exhaust Gas Recirculation on Combustion and Emission of a Marine Diesel Engine

2014 ◽  
Vol 926-930 ◽  
pp. 905-908 ◽  
Author(s):  
Hong Liang Yu ◽  
Gong Zhi Yu ◽  
Shu Lin Duan
Keyword(s):  
Diesel Engine ◽  
Theoretical Basis ◽  
Exhaust Gas Recirculation ◽  
Marine Diesel Engine ◽  
Exhaust Gas ◽  
Cylinder Pressure ◽  
Fishing Vessel ◽  
Marine Diesel ◽  
Gas Recirculation ◽  
Load Conditions

Taking into account the formation of thermal NO, the local balance method and Extended Zeldovich model were used in the paper to simulate the combustion and emission of a marine diesel engine with the AVL FIRE software and to verify the model. The effects of exhaust gas recirculation(EGR) ratios of 0%, 10%and 20% on combustion and emission of a diesel engine were discussed. The purpose of the paper provided a theoretical basis for the marine diesel engine upgrade of Chinese small and medium sized vessels, especially fishing vessel engine. The results show that with the increasing of EGR ratio,the cylinder pressure and combustion temperatures decreases and the peak of soot also shown a downward trend and more gentle, under the same load conditions.

Sign in / Sign up

Export Citation Format

Share Document