Vacuum Insulated LNG Piping
The performance and economic advantages of vacuum insulation have been realized in many industries and applications for decades. Extensive and unnecessary boil-off gas, pipeline insulation maintenance and repair, and running and maintaining large compressors and/or reliquefiers no longer need to be common burdens and expenses for LNG plant and terminal operation. Furthermore, when considering all aspects of the plant design and cost of using VIP versus mechanically-insulated piping, the initial capital investment can be lower with VIP.
Prefabricated vacuum-insulated piping has been used for nearly 50 years in critical applications for transferring liquid helium, liquid hydrogen, liquid nitrogen, and many other cryogenic liquefied gases. Originally developed for its fast cool down and steady-state heat leak values, VIP has evolved into a safe and economic solution for its dependability, ease of site installation, and long-term low maintenance operation.
Advantages of LNG VIP:
INSTALLATION of VIP is a simple process that can reduce construction time considerably. With prefabricated pipe sections provided in common lengths of 30 meters, including elbows and tees, the number of field welds can be reduced by more than 75%. Each connection made in the field can be mechanically-insulated or vacuum-jacketed in a matter of hours. The jacket pipe material is sufficient to support the weight of the spool so supports, guides, and anchors are also simple and easy to install. Additionally, the outside diameter of VIP is approximately 150mm less than the mechanically-insulated pipe which can reduce the size and/or number of piping supports throughout the plant. Our team can also manufacture the VIP in prefabricated, self-contained modules that include trusses, supports, expansion loops, and other process piping for spanning between jetty pilings.
HEAT LEAK PERFORMANCE of VIP is a minimum of one-tenth the value of mechanically-insulated piping. This not only significantly reduces the boil-off gas (BOG) in a steady state operating condition but also results in much faster cool-down time and allows transfer of LNG over much greater distances. Less BOG in the piping transfer system can reduce the number and size of compressors or reliquefiers needed to keep pace with loading or off-loading operations at liquefaction and regasification facilities. This saves a tremendous amount of time and money in capital investment, maintenance costs, and energy costs throughout the life of the plant.
LOW MAINTENANCE of VIP is also an advantage when compared to other types of insulated piping. Once a VIP system is installed and operational it can remain maintenance free for many years. Mechanically-insulated pipe is prone to loss of its vapor barrier causing moisture and ice to build up and deteriorate the insulation resulting in an increased heat leak and more BOG. Maintaining a large mechanically-insulated system sometimes requires a full-time crew. Contact PHPK Technologies today to learn more about our vacuum-insulated piping for LNG service.
