Handbook of Hygiene Control in the Food Industry

12.2 Heat exchanger design

On a purelyheattransferbasis,the designof any heatexchangeris a balance
between achieving the desiredthermal duty and the associated capital and
runningcosts. The increasingcostof energy has also led to a far greater
implementationof heatrecoveryand process integrationapproaches.

Table12.1 Classificationof maintypesof foodindustryheatexchangers

Generictype Optionsavailable Otherpotentialoptions

Plate Standardgap/widegap Platesgasketedor welded
Conventionaldesign,fluidsA and B
flowthroughalternatechannels
Dualplate
Each`plate'consistsof two plates
withan air gap in between
Platein shell
Platepackwithalternateplates
ungasketedand wholepackinstalled
withina shell.Allowslargervolumes
of vapourto be handledthan
conventionaldesign.Liquidflows
throughgasketedchannels

Scraped
surface

Rotary

Bladeson rotatingshaftscrape

internalheattransfersurface.External

jacketfor heating/coolingmedium

Horizontalor vertical

orientation

Linear

Scraperson shaftmovein linear,

reciprocatingmotion

Horizontalor vertical

orientation,multipletubes

availablewithinshell

Tube
(straight)

Monotube

A singletubewithina tube

Multipletubein tube

A singleshellwithinwhichthereare

a numberof smallerdiametertubes

Tripletube

Threeconcentrictubes,fluidA flows

throughinnertubeand outerannulus,

productB thoughinnerannulus

Tubesmaybe smoothor

corrugated.Angleof

corrugationrelativeto the

verticalcan be variedto

alterheattransfer

characteristics

Tube
(coiled)

Monotube

A singletubewithina tube

Tripletube

Threeconcentrictubes,fluidA flows

throughinnertubeand outerannulus,

productB throughinnerannulus

Improvingthe hygienicdesign of heatingequipment 213