WinGD has reported successful factory acceptance tests for the first two X-DF2.0 dual-fuel engines to feature intelligent control by exhaust recycling (iCER).
The new technology is said to enable further improvements to fuel consumption and emissions performance from X-DF engines which were introduced to the market seven years ago.
Targeting even more refined combustion control and optimised performance, WinGD introduced the X-DF2.0 upgrade with iCER technology in 2020. This is reported to improve fuel consumption by around 8% in gas mode and 6% in diesel mode, reduce methane slip by up to 50%, as well as satisfying Tier III NOx emissions limits in both modes. This performance improvement has been confirmed in recent factory acceptance tests for iCER with engine builders CMD in China and IHI Power Systems in Japan.
“We are delighted that the factory acceptance tests prove what we have known from our internal development validations – iCER optimises fuel efficiency and emissions without compromising the reliability and low capex that has made X-DF so popular over the past seven years,” said Dominik Schneiter, vice president R&D, WinGD.
Using iCER’s low-pressure exhaust recycling technology, engines can harness high recycling rates of up to 50%, WinGD reports, allowing the engine to reach higher compression ratios that further reduce fuel consumption and emissions. Exhaust gas recycling can be used across the full engine load profile in both gas and diesel mode. In gas mode, the pilot fuel required is the same across the full engine load range.
WinGD states that iCER technology has proven advantages compared with high-pressure exhaust gas recycling technologies, which offer lower recycling rates, limiting the compression ratios they can reach. It says that this lower combustion control capability of high-pressure EGR systems typically leads to greater diesel pilot fuel injection at higher loads, impacting Tier III compliance, overall emissions and fuel efficiency.
Available with either on-engine or off-engine iCER, X-DF2.0 offers operators the flexibility to optimise combustion with or without exhaust recycling. Using combustion stability mode without recycling, engines run on a ratio of gas and diesel fuel depending on engine load.
X-DF’s injection technology is said to minimise the amount of fuel used and enables engines to achieve stable combustion up to 100% load with the least possible amount of diesel fuel. For gas carriers, iCER can provide further flexibility through fuel sharing mode, which allows operators to use available boil-off LNG supplemented with diesel or VLSFO.
X-DF engines are being deployed across several merchant sectors, with particularly strong uptake on LNG carriers. The X72DF engine has become a popular choice for twin engine LNG carriers, with more than 200 installations and around 37,000 in-service running hours.
