Graphite heat exchangers

For over 50 years, GAB Neumann has been offering a complete range of graphite heat exchangers for the most corrosive applications in the pharmaceutical and the chemical industries. Our product portfolio includes annular groove graphite heat exchangers, graphite coolers, graphite heaters, and graphite block heat exchangers. These pieces of equipment can be used as coolers, heaters, interchangers, absorbers, condensers, or evaporators.

Annular groove graphite heat exchangers

Annular groove graphite heat exchangers (interchangers)  are especially adapted to the heating or cooling of ultra-corrosive liquid chemicals. This specific design allows heat recovery between two ultra-corrosive fluids.

Heavy-duty graphite condensers

Heavy-duty graphite condensers combine efficiency and reliability. They are used for vapor condensation.

Graphite partial condensers

Graphite annular groove partial condensers combine efficiency and reliability. They are used for the condensation of vapors that contain a high amount of non-condensable.

Graphite block heat exchangers

Graphite block heat exchangers offer a versatile and modular design. They can be used for all kinds of applications including the cooling, heating, absorption, condensation or evaporation of ultra-corrosive chemicals.

Graphite shell and tube heat exchangers

Graphite shell and tube heat exchangers offer a versatile design. They can be used for all kinds of applications including the cooling, heating, absorption, condensation, or evaporation of large flowrates of ultra-corrosive chemicals.

Annular groove graphite evaporators

With their specific design our annular groove graphite evaporators & reboilers are especially adapted to the evaporation of highly corrosive chemicals. Annular groove graphite evaporators & reboilers turn the liquid form of a chemical substance such as water or a solvent into its gaseous-form.

Custom-made graphite heat exchangers

Whenever needed GAB Neumann designs and manufactures custom-made graphite heat exchangers to fulfill specific requirements.


  • Impervious graphite: GAB GPX1, GPX1T or GPX2
  • Shell, Pressure plates and flanges: carbon steel or stainless steel
  • Tie rods, nuts, bolts, washers, springs: stainless steel

Key features

  • Design pressure: -1 barg (full vacuum) to +16 barg (232 psig)
  • Design temperature: -60 to +230°C (-76 to 446°F)
  • Heat transfer area: 0,3 to 163 m2 (3 ft2 to 1755 ft2)
  • Design: according to European Pressure Equipment Directive 2014/68/EU (PED) or ASME Code

Key Benefits

  • Outstanding corrosion resistance on one side or on both sides
  • Outstanding heat transfer performance thanks to adjustable cross sections on both sides
  • Flexible modular design
  • High operational safety
  • Short lead time
  • Long lifetime

Main applications

  • Cooling, condensation, heating, evaporation and absorption of ultra-corrosive chemicals
  • Heat transfer between two ultra-corrosive chemicals
  • Heat recovery

Heat exchangers

A heat exchanger is a process device which transfers heat from one medium to another without direct contact between fluids. Heat is transferred by conduction through the exchanger materials which separate the mediums being used. The most common types of heat exchangers in the industry are plate and frame heat exchangers as well as shell and tube heat exchangers. The thermal performance of heat exchangers can vary significantly. It is therefore essential to select the type of heat exchanger that is the most adapted to the specific application. There are a number of considerations including flow rate, pressure drop, design pressure and temperature, materials compatibility, fouling, and many more that should be taken in account. 

GAB Neumann’s graphite heat exchangers

GAB Neumann’s graphite heat exchangers are designed to cool down, condense, heat up, evaporate, sublime, crystallize, or absorb ultra-corrosive chemicals. Safety, reliability, availability, and performance on the long-term are our primary considerations when we size, design and manufacture heat exchangers.

Whether we talk about our annular groove or block heat exchangers, our extended and highly customizable graphite heat exchanger portfolio enables us to provide particularly adapted solutions to ultra-corrosive heat transfers. All our heat exchangers’ designs are totally modular to best fit with individual process specification. The number and size of blocks or discs, the drilling diameters, the channel widths, the nozzle diameters, as well as the number of passes both on process and service sides can be adapted to best meet the velocities, pressure drops, and heat transfer requirements.

Our annular groove graphite heat exchangers are dedicated to the heating and cooling of ultra-corrosive liquids. Their specific design prevents fouling and ensures a high overall heat transfer coefficient.

Our annular groove heavy duty graphite condensers are dedicated to the condensation of ultra-corrosive vapors. They can also be used as crystallizers.

With their large specific heat transfer surfaces on process side, our annular groove graphite partial condensers are particularly adapted to the condensation of vapors containing a high amount of non-condensable gases. They are mostly used as secondary condensers after larger primary condensers.

Our cylindrical block heat exchangers are extremely versatile. They can be used as condenser, coolers, heaters, absorber or evaporators. They can be fitted with all kinds of optional features such as sight glasses, demountable headers to better fit the process requirements.

All our graphite heat exchangers are machined after phenolic resin impregnation thus guarantying a totally free of resin heat transfer surface and ensuring therefore the highest possible heat transfer rate.

Industrial processes:

  • Phosphoric acid
  • Sulfuric acid
  • Hydrochloric acid
  • Hydrofluoric acid
  • Bromhydric acid
  • Crop protection
  • Fumed silica
  • Silicones
  • Titanium dioxide
  • Fine chemicals
  • Active pharmaceutical ingredients
  • Carbon steel and stainless-steel pickling
  • Copper electrolysis
  • Epichlorohydrin
  • Vinyl chloride monomer
  • Fire retardants
  • Flavors and fragrances
  • Vitamins
  • Isocyanates
  • Viscose
  • Polycarbonate
  • Coagulants
  • Treatment, purification and concentration of spent acids
  • Sulfuric acid dilution
  • and many more…

GAB Neumann GmbH

Alemannenstrasse 29

79689 Maulburg


Tel: +49 (7622) 6751 0

Fax: +49 (7622) 6751 20

GAB Neumann GmbH | Alemannenstrasse 29 | D-79689 Maulburg | Phone +49 (7622) 6751 0 | Fax +49 (7622) 6751 20 | E-Mail |