Alfa Laval announced the launch of its gasket-free, 100% stainless steel AlfaNova M HP 400 plate heat exchanger for use as cargo condenser and/or heater aboard liquid petroleum gas (LPG) carriers.
A compact, lightweight alternative to traditional shell-and-tube heat exchangers, the AlfaNova M HP 400 assists the ship owner in meeting the requirements of the Chemical Distribution Institute’s “Ship Inspection Report for Chemical and Gas Tankers,” seventh edition. It also provides ship owners with the benefits of higher efficiency, increased safety, greater temperature flexibility, and lower total cost of ownership.
With the introduction of the AlfaNova M HP 400 to the maritime industry, Alfa Laval now provides the LPG market with the option of using this cost-effective cargo condenser as an indirect system instead of using shell-and-tube or welded-type condensers.
“We have adapted the proven fusion-bonded AlfaNova heat exchangers to the cargo conditioning requirements of LPGs,” says Johan Lennartsson, Alfa Laval Marine & Diesel’s regional marketing manager who is responsible for working with contractors and shipyards for liquid gas carriers. “By combining an innovative 100% stainless steel brazing filler and patented fusion technology, AlfaFusionTM, in a compact heat exchanger, we are able to provide an ideal cargo condenser for indirect LPG reliquefaction systems. The AlfaNova M HP 400 has the same low weight and high efficiency as a copper brazed plate heat exchanger but is suitable for all LPG media including ammonia.”
Versatility and safety for indirect cargo cooling
As an indirect cargo condenser, the AlfaNova uses fresh water or glycol solution as the cooling media to condense gas vapour into its liquid form. The fresh water is cooled by a traditional gasketed titanium plate heat exchanger, which uses seawater as the cooling media. This type of heat exchanger is easy to clean because it provides the crew with full accessibility to seawater side.
Safety is another advantage of an indirect system. In case of a leak in the traditional direct cargo condenser, gas may enter the seawater side in the cargo condenser and release valuable cargo into the harbour. However, in the event of a condenser leakage in an indirect system, gas can only enter the intermediate loop.
Energy savings and fast turnaround time
The AlfaNova M HP 400 offers two main advantages over indirect systems that are currently used:
- Lowering the condensing pressure, which translates to tangible cargo compressor energy savings.
- Increasing the condensing capacity thereby reducing port-to-port time. This, of course, has a positive effect on both costs and transportation efficiency.
Testing soon underway aboard an LPG carrier
Danish shipping company Lauritzen Kosan, specialized in the transportation of LPG and chemical gases has cast its vote of confidence in the AlfaNova by recently signing a contract to purchase, install and test the AlfaNova M HP 400 on one of its vessels. The company currently operates six LPG carriers that use central coolers and stainless steel AlfaRex plate heat exchangers as cargo condenser systems. By installing the AlfaNova M HP 400 alongside the AlfaRex unit, Lauritzen Kosan intends to minimize power consumption in order to keep the operating costs of its reliquefaction plant as low as possible and reduce in-port turnaround time.
Lightweight and compact
A patented AlfaFusion bonding technique stands behind AlfaNova innovation, which has proven effective in tough industrial applications, such as industrial ammonia chillers used as evaporators and condensers. Weighing in just under 400 kilograms (900 pounds), the AlfaNova M HP 400 is much lighter than current technologies. Its small footprint occupies a mere 0.5 square metres, which is a fraction of the space required by comparable condensers.
What lies ahead: LNG fuel applications
“We are aware of the keen interest in using liquefied natural gas (LNG) as fuel, in order to comply with the new International Maritime Organization regulations in sulphur emission control areas (SECAs),” continues Lennartsson. “We believe that, in the future, owners of LNG fuelled vessels together with Alfa Laval will find many uses for AlfaNova in LNG fuel handling systems.”
LNG World News Staff, September 20, 2012;