What is printed circuit heat exchangers?
Printed Circuit Heat Exchangers (PCHEs) are characterised as
high integrity plate type heat exchangers. They are fabricated from
flat metal plates (sheets) that have fluid flow channels chemically
etched into them using the same process as printed circuit hence
the product name.
The etched plates are stacked and diffusion bonded together to
make the core of the heat exchanger(s). PCHEs can be made of one or
several cores welded together to suit the duties required. Headers
and nozzles are attached to the core(s) to complete the
exchanger.
PCHE are highly compact, highly robust exchangers and can
achieve high thermal effectiveness of over 98% depending on the
process:
- PCHE are four to six times smaller than conventional shell and
tube heat exchangers of the equivalent duty.
- They have a pressure capability in excess of 600 bar (9000
psi) and can cope with extreme temperatures, ranging from cryogenic
to above 900°C (1650°F).
They are well established in the upstream hydrocarbon
processing, petrochemical and refining industries. They can
incorporate more than two process streams into a single unit. This
design feature has space and weight advantages, reducing exchanger
size together with piping and valve requirements.
Additional functions can be included in the exchanger design,
such as chemical reaction, mass transfer and mixing, optimising the
process considerably.
The association of chemical etching and diffusion bonding
processes into a single product allow the use of a wide range of
materials of construction enabling the use of a wide range of clean
fluids in the heat exchanger, including corrosive ones.
