(60g) LNG Applications of Printed Circuit Heat Exchangers

In industrial processes heat/cold energy is transferred by a variety of methods, including conduction and conduction-convection in exchangers. Often exchangers operate under steady-state conditions, but in many processes they operate cyclically, as in regenerative furnaces and some cryogenic processes.

Brazed aluminum plate-fin heat exchangers have been widely used for their distinctive features of compact size and cost competitiveness. However, they are not suitable for services requiring durability and robust operation with high temperature differences between cold and hot fluids.

Printed Circuit Heat Exchangers (PCHEs) are compact, high integrity heat exchangers which have been widely used on offshore platforms for many years. They are typically just 20% of the size of equivalent shell & tube heat exchangers, but unlike most compact exchangers, they have a very high pressure capability up to 8700 psi (600 bar). Diffusion bonded stainless steel construction allows far greater temperature differences than with brazed aluminum plate-fin technology and PCHEs are also not limited to the stringent warm up / cool down rates associated with brazed construction.

This paper discusses the technical design features of Printed Circuit Heat Exchangers and their application to the LNG industry. This paper also addresses some of technical/operational aspects of these diffusion bonded exchangers.