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Alfa Laval – spiral heat exchangers

The all-round heat transfer solution

Spiral-shaped heat exchangers are not a new idea

– but Alfa Laval has perfected the design.

Exceptional compactness and self-cleaning design

make Alfa Laval spiral heat exchangers extremely

versatile. Ideal for everything from dirty fluids to high

vacuum condensation.

Product rangesWe provide fixed-size and customizedproduct ranges to meet the needs ofour customers.

Fixed-size rangesWe make small units for general use,and for application-specific purposessuch as the wastewater industry.

Customized rangeTo meet requirements for a range ofsizes and specifications, the majority ofthe spiral heat exchangers we supplyare individually customized.

4 Alfa Laval – spiral heat exchangers

The idea of using spiral-shaped fluidchannels for heat transfer arose inresponse to a particular customer’sprocess problem. Other technologieshad failed, but in this case a spiralproved to be the perfect solution.

That was nearly 70 years ago.

Today, spiral heat exchangers fit per-fectly into Alfa Laval’s extensive prod-uct portfolio – still providing customerswith optimum process solutions.

Spiral heat exchangers are particularlyuseful when a process is “dirty” or “difficult”. In such circumstances, spiralheat exchangers have clear advan-tages over other products that employheat exchange technologies.

Alfa Laval spiral heat exchangers aredesigned on the basis of our extensivethermal and mechanical experience,acquired from both our customers andour production sites.

Customer needs met with customized designNo two customers are alike, and nei-ther are their plants or their processes.To meet all these different needs, engineering solutions and processequipment must be adaptable.

Each Alfa Laval spiral heat exchangerdesign can be customized to meet theprecise process and application needsof individual customers.

Unique shape has unique propertiesA spiral heat exchanger is preciselywhat it says – a circular heat ex-changer with two concentric spiralchannels, one for each fluid.

The curved fluid channels provide opti-mum heat transfer and flow conditionsfor a wide variety of fluids, while keep-ing the overall size of the unit to a minimum.

The result is a heat exchanger that pro-vides maximum heat transfer efficiency,while only taking up a minimum ofinstallation space.

The perfect solutionFrom dirty fluids to high vacuum condensation– spiral heat exchangers from Alfa Laval can do it all

Alfa Laval – spiral heat exchangers 5

Heat exchange duties that benefit fromthe strengths of spiral heat exchangersinclude:● liquid/liquid heating, cooling or heat

recovery, where one or both of the fluids may cause fouling.

● vapour/liquid condensing, particular-ly at very low pressure and/or high-volume flow.

The design, shape and size of the spiral channels can be customized sothat they are a perfect match for thedemands associated with a wide rangeof process fluids, thermal duties andindustrial applications.

Strong on customized solutionsThe spiral heat exchanger is a very ver-satile product.

Many of the duties performed by heatexchangers require one channel perfluid, and this can be a distinct benefit.

Some customers choose spiral heatexchangers to boost the performanceof their existing processes. Others usethem for thermal duties in processesthat would otherwise simply be impossible.

Whether replacing existing “inefficient”technology or being used in revolution-ary new applications, spiral heatexchangers are the first choice forprocesses that involve demanding liquid/liquid duties.

The self-cleaning heat exchanger fordemanding liquid/liquid dutiesSingle channel technology makes keeping clean easier

Single channel technology – whatgoes in must come outAs the name indicates, single channeltechnology means that both fluidsoccupy a single channel, which allowsfully counter-current flow. One fluidenters the centre of the unit and flowstowards the periphery. The other fluidenters the unit at the periphery andmoves towards the centre.

The channels are curved and have auniform cross section, which creates a“spiralling” motion within the fluid.

The fluid is fully turbulent at a muchlower velocity than in straight tube heatexchangers, and each fluid travels atconstant velocity throughout the wholeunit. This removes any likelihood ofdead spots and stagnation.

Solids are thus kept in suspension, andthe heat transfer surfaces are keptclean by the scrubbing action of thespiralling flow.

Self-cleaning keeps costs downThe self-cleaning properties of spiralheat exchangers ensure that the reli-able performance of efficient heattransfer is guaranteed, with minimumdown time for maintenance.

In some duties where alternative heatexchangers would need regular clean-ing, disassembly, repair and maintenance, a spiral heat exchanger

performs for much longer periods, and only requires maintenance duringroutine plant shutdowns.

Fewer unitsThe increased thermal efficiency result-ing from the fully counter-current flowvery often means that a particularassignment requires fewer spiral heatexchangers than the straight-tubealternative.

Lower installation costsSpiral heat exchangers only require avery small area for mounting andaccess, resulting in lower unit installa-tion costs compared with other heatexchangers.


Fewer units, less down timeIn a coke oven plant, four shell-and-tube units were replaced by just onespiral heat exchanger. This savedspace and cost, while increasingperformance at the same time.


Easy accessWhen processes involve fluids that arecapable of causing a high degree offouling, it is important to have easyaccess to the inside of the heatexchanger for cleaning and inspection.

Compared with other types of heatexchanger, spiral units provide the bestaccess to their heat transfer area –with no special tools or lifting equip-ment required.

Each fluid channel is easily accessedvia its cover, exposing the whole of theheat transfer surface.

Two covers enable one or twofouling fluidsBoth hot and cold channels aredesigned to perfectly match the specialneeds of the fluids being used and thethermal duty being performed. Thisprovides total operational securitywhen using either one or two fluids thatcause high fouling.

This is a major advantage for cus-tomers that want to recover heat fromone dirty fluid to another.

Spiral units are the only type of heatexchangers capable of direct heatinterchange between two fluids thatcause high fouling.

Full draining for batch operationAll spiral heat exchangers can bedrained in position, without any need todisconnect pipework or to open the units.

For applications where complete drain-ing of the process fluid is required on aregular basis, the spiral heat exchangercan be installed in an upright position.

This is particularly useful for batch pro-duction processes as it makes it pos-sible to empty all fluid from the unitbetween batches.

Unique performance – the spiral’s highefficiency and easy access designmake heat recovery possible with twofouling fluids – shown here at amunicipal sludge pasteurization plant.

One of the best examples of the flexi-bility of a spiral heat exchanger is itscapability as a condenser.

Different condensing duties place dif-ferent demands on a heat exchanger.The desired condensing performanceis achieved by determining the flowpath of the vapour.

Alfa Laval spiral condensers perfectlycomplement Alfa Laval’s other processcondensers – the AlfaCond and theCompabloc – to provide customerswith a full range of condensers for theentire range of their processes andapplications.

The customized condenserThe versatility of spiral heat exchangers makes them idealfor customized solutions

Maximum product recovery withcounter-current condensingTo condense a mixture of vapours and inert gases, a heat exchanger needs a long flow path. In a spiral heat exchanger this is easily achieved,as the vapour flows in a direction thatis counter-current to the cooling liquid.

This results in a very compact con-denser with the best heat transfer efficiency for maximum productrecovery. The counter-current spiral

condenser can also be designed tosub-cool the condensate and/or theinert gases.

Cross-flow condensing with thelowest possible pressure dropCondensing large volumes of pure vapour needs a unit with a large cross-sectional area and a short flow path. To achieve this, the vapour passes through the con-densing channel in cross flow.

When the vapour/condensate operatein cross flow, the pressure drop is virtu-ally undetectable. This makes the spiralcondenser ideal for systems that oper-ate at very low pressure.


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Two units in one – cross-flow andcounter-current paths in the same unitThe flexible flow-path arrangement andinstallation possibilities provided byspiral heat exchangers give themimportant advantages compared withother condensing solutions.

Two heat exchange duties can be per-formed within a single spiral to furtherreduce capital equipment costs, and tomaximize operating efficiency.

For example, a spiral heat exchangercan act as a condenser and sub-coolerfor condensate and/or inert gases, oras a pre-heater to remove sub-coolingfor vaporizer and reboiling duties.


Installation costs reduced stillfurtherBecause of their function, condensersare often mounted high up at the topof distillation columns.

Due to this high placing, all the ancillaryequipment must be supported on aseparate structure. This greatly in-creases the costs of installation,running and maintenance.

Spiral condensers, however, are avail-able as self-contained units or, moreimportantly for many customers, as acolumn-mount to fit directly onto orwithin an existing distillation column orstripper tower.

It is also possible to build more thanone spiral heat exchanger unit into acomplete condensing tower to accom-modate multiple condensing stages,such as cooling water, chilled waterand refrigerant.

Condensers can also separateSeparation of the condensate pro-duced from the inert gases takes placeinside the spiral. Condensate cantherefore easily be fed back into thecolumn for reflux, or removed for fur-ther processing, without the need forexternal separation equipment.

Fitting a spiral condenser to a towerthus not only increases condensingperformance, but also reduces ancillaryequipment costs and removes theneed for support structures.

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Working closely with our customershelps them to optimize their processesand introduce new forms of heatexchange – such as this fully builtcondensing tower with three spiralbodies.

Direct mounting of a spiral condenserat a stripper tower reduces installationcosts, increases product recovery andreduces pollutant escape.

Corporate Brochure 12

History, experience and expertiseIt takes experience to build the kind of expertise that provides answers

The largest manufacturer of heattransfer equipment in the worldOur worldwide sales and service repre-sentatives ensure that we can provideexcellent local service to all prospectiveand existing customers, while alsodrawing on the wider experience andexpertise accumulated within our global organization.

This wealth of knowledge and experi-ence is especially relevant to the spiralheat exchanger.

Alfa Laval has been making spiral heatexchangers for more than forty years.During this period, Alfa Laval has pro-duced more than 30,000 spiral unitsfor a wide variety of industries and cus-tomers all over the world.

Today, Alfa Laval has three productionsites that provide worldwide supplyand service to its spiral heat exchangercustomers.

They are situated in:● France● The United States● India

Please contact your local Alfa Lavalrepresentative to arrange a visit andrequest a tour of our facilities.



Continual developmentSpiral heat exchangers are a well-established product, and have beenaround for a long time. Nevertheless,Alfa Laval heat exchangers aredesigned using the very latest tech-niques and testing methods.

Our sales staff are equipped withsophisticated, state-of-the-art calcula-tion and quotation tools.

Our manufacturing and R&D depart-ments are constantly working to makeimprovements on production tech-niques and component design – againdrawing on the vast pool of skills andknow-how available within Alfa Laval.

Inspiration from our customersOur best source of information andinspiration is our customers.

Spiral heat exchangers are customizedproducts, engineered to meet theneeds of each new installation. Afterall, no two customers are alike, andneither are their plants or their pro-cesses.

Over time, spiral heat exchangers havebecome standard equipment for agreat many processes in many industries.

We enjoy working closely with our cus-tomers to meet the challenge ofimproving their processes. Selectingspiral heat exchangers can help cus-tomers in the following ways:● by improving an existing thermal duty● by helping to develop alternative

solutions and new processes

Whatever the duty, Alfa Laval has anextensive catalogue of references, thenecessary experience, and a completeheat exchanger product portfolio. Weare confident of being able to recom-mend the best heat exchange solutionfor your process.

Minimum Maximum

Area range per body 1 m 2 700 m 2

10 ft 2 7000 ft 2

Design temperature -100 0C 400 0C-150 0F 750 0F

Design pressure Full vacuum 40 barg and above 580 psig and above

Pressure vessel codes PED, ASME, AS1210 and others

Standard construction materials Stainless steel, carbon steel

Other construction materials Any metal that can be cold formed and welded – includingDuplex, titanium, Hastelloy, 904L

Performance range


Performance and applications

Typical applications


Type of fluids and gases Fouling liquids – containing solids, fibres, liquors, slurries and sludges.Gases – pure vapour and mixtures with inert gases.

Type of duty Liquid/liquid – preheating, heating, cooling, interchanging, heat recovery.Vapour/liquid – top condensers, reflux condensers, vacuum condensers,

vent condensers, reboilers, gas coolers.

Type of industry● Petrochemical● Refinery● Steel making● Pulp and paper● Metal/ore processing● Wastewater treatment● Pharmaceutical● Vegetable oil processing● Distillery

A lifetime commitmentFor us at Alfa Laval, our obligation toyou as a customer does not stopshort at delivery. Our Parts & Serviceorganization is there to ensure thatyour process always runs at peakperformance. This is a commitmentthat extends throughout the lifetimeof the system. We call it NonstopPerformance.

Nonstop Performance is based on ourglobal network of experts, who arealways on standby to provide you withgenuine spare parts on site, in morethan 50 countries, 365 days a year,right around the clock.

Nonstop Performance


In terms of service, we speak yourlanguage. Alfa Laval service is basedon a profound insight into the needsof the process industry. We see everyproduct as part of a process andunderstand the role it plays withinthat process. We can therefore workin close collaboration with you to tailoran individual service package thatmatches your requirements perfectly.

Service must result in bottom-linebenefits. We therefore help you tocalculate the savings that will resultfrom any proposed service package,and the real-term benefits it willprovide.

Challenge us to show you!

Alfa Laval in brief

Alfa Laval is a leading global provider ofspecialized products and engineeredsolutions.

Our equipment, systems and servicesare dedicated to helping customers tooptimize the performance of theirprocesses. Time and time again.

We help our customers to heat, cool,separate and transport products such asoil, water, chemicals, beverages, food-stuffs, starch and pharmaceuticals.

Our worldwide organization worksclosely with customers in almost 100countries to help them stay ahead.

How to contact Alfa LavalUp-to-date Alfa Laval contact details forall countries are always available on ourwebsite at www.alfalaval.com

PPM00056EN 0305

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