Norwegian purse seiner/trawler and factory vessel Kvannoy has become the world’s first fishing vessel to benefit from Humid Air Motor (HAM) technology following a rebuild performed at MAN PrimeServ Frederikshavn, Denmark.
The main engine is an MAN 16V28/32A rated 3,920kW at 775r/min. The seatrial test results showed a NOx emission of only 3.6g/kWh, measured according to the IMO MARPOL, E2 test cycle. This corresponds to a total NOx reduction of 61.3%, compared to the emission of the main engine running with its original charge air coolers – without HAM.
The new HAM NOx level is 1.2 g/kWh above the IMO Tier III limit and on an annual basis Kvannoy’s accumulated NOx emissions will be reduced by 50 tonnes. The economic benefits are annual savings of NOK 800,000 (€98,660/$138,517) due to reduced NOx taxes for operation within Norwegian waters.
The calculated payback time for the HAM retrofit is approximately three years.
With the HAM system, the turbocharger charge air is saturated with sea water vapour before it enters the charge air channels and engine combustion chambers. As a result, the temperature peaks in the combustion process are lowered, and the formation of NOx is reduced.
The HAM system layout and installation onboard Kvannoy was performed in close co-operation with the DNV classification society. Additionally DNV carried out the final emission analysis, including NOx measurements during seatrial – running the main engine both with and without HAM.
MAN PrimeServ handled the installation and engine retrofit in co-operation with French colleagues and HAM experts. The HAM system units, as well as the control and monitoring equipment, were supplied by MAN Diesel & Turbo France.
