Alfa Laval recently celebrated its 100th anniversary in the marine industry. As the company enters its second century of marine service, it is focused on the challenges ahead, including its heat exchanger offering, which is rapidly developing to meet the challenges of fuel gas supply, explains Global Business Manager, Heat Transfer Equipment, Johan Lennartsson.
Alfa Laval continues to assert its leadership in marine heat transfer. Even in gasketed plate heat exchangers, an industry staple, the company is pushing boundaries. Recent years have seen the introduction of maintenance-friendly ClipGrip gaskets and more robust frame designs, but also process advances, such as a significant increase in heat transfer area through Alfa Laval’s CurveFlow plates.
Some of its most important innovations are occurring in a new range of duties, driven by the switch to low-sulphur fuels. As vessels move towards LNG, LPG, methanol or even other gas alternatives, they still need to condition the fuel before it reaches the engine. The variety of different fuel gas systems creates an extremely challenging range of heating and cooling needs – all of which Alfa Laval is committed to meet.
The industry’s widest thermal portfolio
Alfa Laval has more than 20 years of experience in heating and cooling LNG/LPG at sea. Building on this expertise, the company has developed a wide portfolio of efficient, small-footprint heat exchangers for key heating and cooling applications in marine fuel gas systems.
The solutions include versatile semi-welded and copper-brazed plate heat exchangers, but also unique products like the fusion-bonded and gasket-free Alfa Laval AlfaNovaM, produced in 100% stainless steel, or the specially engineered Alfa Laval Duroshell, a robust plate-and-shell model that can perform low-pressure LNG vaporisation duties.
We continue to explore both new designs and new manufacturing techniques, by closely matching the demand of the applications, we achieve the highest performance.
Dealing with extreme temperatures and pressures
At the far end of the performance scale is the Alfa Laval printed circuit heat exchanger (PCHE), a diffusion-bonded unit for temperatures from cryogenic up to 800°C. Tailor-made with fully customisable fluid channels, it handles pressures up to 650 bar, such as those found in high-pressure gas injection.
The PCHE is a unique technology on its own, up to 80% smaller and lighter than the shell-and-tubes otherwise required for these duties. But it is also a critical part of complete conditioning systems for fuel gas supply, where LNG is pressurised at more than 300 bar and vaporised at cryogenic temperatures.
Application as well as technology leadership
The extreme temperatures and pressures involved in fuel gas applications are not to be taken lightly. For this reason, Alfa Laval is focused not only on the development of its technology, but also on how it is used. The company is conducting fuel gas application testing – the most comprehensive of its kind in the marine industry – that is due to be completed during 2018.
Safety and reliability are crucial for heat exchangers in fuel gas systems, as they are part of the vessel’s main propulsion. These are new applications where the number of reference systems is limited, so it’s important to establish the operating parameters with certainty. Customers need to know not only the design limitations, but also the practical considerations to avoid freezing and other potential safety issues.