Given the poor quality of fuel on which many ship engines currently run, the global shipping industry has been pilloried recently for its poor emissions performance. Now, it has an opportunity to assist in shore-side emissions reduction by once again consuming some of the products which nobody else wants.
Seatrade recently reported on glycerol, also known as glycerine, a by-product of the biodiesel production process. Biodiesel use is growing in land-transportation applications because of its favourable emissions profile, but experts are saying that refiners will have to find uses for the surplus of glycerol in order to make a ramping-up of production financially viable.
If adopted by shipping, glycerol could potentially match the emissions-saving properties of low-sulphur marine diesel or even liquid natural gas at a fraction of the cost of dirtiest bottom-of-the-barrel fuel oil, and would be available in plentiful supply. Now, the Glycerine Fuel for Engines and Marine Sustainability (GLEAMS) project, a joint programme involving Lloyd’s Register, Aquafuel Research, Gardline Marine Sciences, Redwing Environmental and Marine South East, is moving to facilitate exactly that.
Currently, the infrastructure is simply not available for a quick adoption of the new fuel. However, there is an extremely strong case if distribution can be set up. David Rea, project manager at Marine South East, tells Seatrade: “Glycerol represents a more thermally efficient combustion process than marine diesel oil (MDO) or heavy fuel oil (HFO), and therefore the basic carbon reduction calculation is improved. Cleaned fuel-grade glycerol will be 2-3% of the carbon level of MDO or HFO.”
On top of this, glycerol is more stable than most fossil fuels - nearly impossible to ignite accidentally, water soluble, and non-toxic, potentially making storage and retrofit far easier. “The marine [storage] requirements will need to come from other sources,” Rea notes, however: “On land we prefer internally coated steel fuel tanks or stainless steel tanks; no fire risk criteria and no vapour risk criteria.”
Many standard HFO engines could be converted with relative ease; retrofit would include new fuel piping, automated fuel valves, automated inlet air valve installation and exhaust catalyst installations, Rea explains. “If the standard engine automation and control systems are at a low level then additional automation hardware and software may be required.”
Glycerol has already been adopted by a number of land-based industries, including Anaerobic Digestion (AD) plants and Cogeneration (CHP) plants. The improving utilisation has increased its price from $80 per tonne to $240 in recent years – still less than a third of the price of heavy fuel oil in many bunkering locations - where it has remained relatively stable. However, Rea notes, “The quantity of crude glycerol produced from biodiesel production will increase due to the accepted increase of biodiesel manufacture.”
Now, shipping faces the intriguing prospect of being able to do for biofuel production what it has done for oil refining. The prospect of a workable distribution network before the IMO’s 2020 sulphur deadline is wildly optimistic, but to a shipping market squeezed by rocketing fuel costs, the possibility of an alternative could be an exciting proposition.