Alfa Laval has announced the launch of its DuroShell plate-and-shell heat exchanger, which is optimised for use as an LNG vaporiser.
The robust DuroShell provides higher thermal efficiency than conventional plate-and-shell designs, as well as excellent fatigue resistance. Thanks to new research into glycol freezing, it can now be used in even more compact and cost-effective installations.
“The continued rise in the number of vessels sailing with LNG is one of the most significant trends in today’s marine industry,” says Jonny Hult, Head of Marine Heat Transfer Equipment at Alfa Laval. “With more and more ships relying on LNG as fuel, we are seeing greater demand for vaporiser technology that can dependably resist freezing and the fatigue caused by pressure and temperature. DuroShell is exceptional in this regard.”
DuroShell has been optimised for use as a vaporiser in fuel gas applications. With its 100% stainless steel design, it can reliably handle LNG entry temperatures that approach -170°C or lower. Now Alfa Laval has also performed an extensive laboratory freeze testing, gaining knowledge that will lead to lower capital and operational costs.
“Extreme low temperatures are not an issue for DuroShell, but a glycol mix with a freezing point of around -50°C has the potential to freeze when it meets plate surfaces as cold as -90°C,” Hult explains. “Solving this problem with a higher glycol flow is a very expensive solution for our customers, so Alfa Laval has worked with SINTEF Energy Research to find the correlation of flows on both sides and thereby avoid freezing of fluid on the hot side.” Hult concludes that this will let shipbuilders use a more compact plate-and-shell design with smaller pumps and pipes, which, in turn, will mean CAPEX and OPEX savings for the ship owner.
DuroShell’s ability to withstand the large temperature differences in fuel gas supply systems stems partly from its CutWing plates, which feature the patented Alfa Laval RollerCoaster™ plate pattern. This design provides high turbulence that improves heat transfer efficiency and thus significantly reduces the risk of freezing and fouling.
Another unique feature is the PowerPack™ distribution tubes, which run all the way through the plate pack and secure an optimised flow distribution onto the heat transfer surface. This design further enhances the strength of the plate pack for added fatigue resistance in demanding LNG duties.
Read the article online at: https://www.hydrocarbonengineering.com/product-news/26042019/alfa-laval-launches-new-heat-exchanger/