The CIMAC Position Paper ‘Gas Engine Aftertreatement Systems’ has been compiled by the CIMAC WG17 'Gas Engines' members and provides an overview regarding the exhaust aftertreatment systems for stationary, 4-stroke natural gas engines. This position paper describes the potential impact of stricter exhaust emission standards on engine performance, engine design and the requirements for exhaust aftertreatment systems for natural gas engines. The paper also aims to compare the characteristics of exhaust emission formation of natural gas engines that are operated in one of two regimes, i.e., learn-burn or stoichiometric.
In addition to the performance comparisons between lean burn and stoichiometric engines the paper also presents a relative costs comparison of different aftertreatment systems for both lean burn and stoichiometric engines.
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In 2018, the industry experienced a series of marine fuel incidents impacting the operation of more than 100 vessels. The specialists of CIMAC WG7 Fuels have prepared a statement .. more
The guideline aims to understand the issue of cold corrosion which has been a regular occurrence with operators of large two-stroke marine engines due to engine operation at low loads. It intends .. more
The CIMAC Position Paper ‘Gas Engine Aftertreatement Systems’ has been compiled by the CIMAC WG17 'Gas Engines' members and provides an overview regarding the exhaust aftertreatment .. more
The CIMAC Working Group 7 Fuels has prepared and issued a guideline to provide answers to the questions that may arise with the publication of ISO 8217:2017, the latest specification of .. more
This guideline follows on from the CIMAC WG7 guideline No 09:2014  which set out the differences between the ISO 4259 approach and that adopted under MARPOL Annex VI in respect of fuel .. more
The CIMAC Working Group 7 Fuels has prepared and issued a guideline on filtration of residual fuels. Traditionally, filters have been considered a safeguard for marine engines, however, a more .. more
This position paper describes how gas engines are influenced by the quality of the gaseous fuel provided. This topic is becoming increasingly important as highly fluctuating renewable energy .. more
New 0.10% sulphur (S) marine fuels recently introduced in the market offer an economically attractive alternative to conventional distillate fuels such as DMA. Before purchasing a new fuel product, .. more
With the introduction of MARPOL Annex VI, the sulphur content of a particular fuel oil is now often the primary factor in assessing whether or not that fuel oil is acceptable for intended use. .. more
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Over the last few years gas-fuelled engines have become more popular also in the marine industry both for on-board power generation and propulsion duties. Whereas the use of gas-fuelled marine .. more
Crankcase explosion is caused due to the overheating of one of the cylinders in the main machinery space. The consequences of the explosion is severe and it affects the working of other engines. .. more
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Especially regarding switch of .. more
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This document intends to collect information about the situations experienced where the Ignition and Combustion properties of the fuel are suspected of having influenced negatively on the .. more
On 10 October 2008, the IMO Marine Environment Protection Committee at its 58th session, by Resolution MEPC.177(58), has adopted amendments to the Technical Code on Control of Emission of Nitrogen .. more
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Today, mainly for 4-stroke medium and .. more
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Current commercial residual fuel specifications cannot reliably predict the ignition and combustion characteristics of a fuel due to lack of a suitable test parameter. They cannot therefore protect .. more
This document briefly explains the importance of technique specific emission regulations. Some general features of the stationary engine plant are presented, such as:
engine types & fuel .. more
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LNG, liquefied natural gas, is natural gas cooled down to about –161 °C at atmospheric pressure and transported as a liquid. It is now rapidly becoming a widely used engine fuel in .. more
Control of Emissions of Air pollution from Locomotive Engines and Marine compression-ignition engines less then 30 litres per cylinder.
This publication discusses the following issues: .. more
Subject: Implementation of new or revised UR
On the occasion of the last CIMAC WG2 meeting at Vaasa in April 2005 we ocassionally learned that some UR have been revised and .. more
Subject: Delivery of EIAPP Certificates
Since that moment when the new IMO regulations regarding NOx came into force claims from engine builders increased. The engine builders .. more
Subject: Attendance at Type Approval Tests (TAT)
Background: Within the last years quite some experience was gained during Type Approval Tests. We have realized that Class surveyors well attended .. more
Use of low sulphur diesel fuels in coastal waters.
CARB / EPA propose that Ocean going ships must use only distillate fuels (diesel oil) with a low sulphur content and a low content of aromatic .. more