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Technology

The Catalytic Reaction

The Vulcan catalytic heater is a diffusion type heater, that operates on a chemical oxidation reduction process that reduces the methane or propane gas in the presence of platinum and oxygen, into moisture, carbon dioxide, and produces Infra red energy from this reaction. There is no forced air or oxygen supplied for the chemical reaction. Air that is required for the reaction is diffused through the heater surface and into the reaction sites at the platinum/gas interface. The catalytic reaction requires that the catalyst be at a temperature of 300° F. This is achieved from an electrical preheat element that is activated for 15 minutes.


After that time either a heat sensitive thermoswitch is closed indicating that the heater is ready to receive the gas or the Manual Start process is initiated and the catalytic process is begun. The gas enters the heater panel and is evenly dispersed through a plenum chamber within the heater. The gas is then distributed into the hot catalyst where it reacts with the platinum in the presence of air. The position of the reaction within the depth of catalyst is dependent upon the volume of gas entering the catalyst. The high-end flow of 6,000 BTU/H per square foot of heater sends the reaction close to the heater surface, at the low-end flow the reaction site is towards the bottom of the catalyst below the heater surface. The surface temperatures will be at high of 950°+ F for high fire, down to 400° F at low fire.

There is no flame with the reaction of gas. As such these heaters are approvable for heating hazardous areas. When products such as Acetone, MEK, Toluene, Octane, and Naphtha are sprayed onto the heater surface there is no combustion of the solvents.

When installing heaters in a totally engineered Vulcan Catalytic System all specifications, installation instructions, plumbing and wiring directions are provided to insure a successful installation.

High Radiant Heaters vs Catalytic Heaters

Catalytic infrared heaters are different than conventional gas radiant heaters that have traditionally been used for drying and curing processes. These conventional heaters use a pre-mixed gas/air mixture that passes through an emitter placed in a housing. The ignition of the mixture is initiated by an electrical spark at the exit point of the gas mixture. Conventional infrared heaters produce an energy flux of 10,000to 120,000 Bbtu/hr2 at 1300°F to 2100°F emitter temperature. Depending on the type of emitter and flow rates, the heaters also can produce visible flames. This characteristic may be an issue in certain types of applications. In recent years catalytic infrared heaters have gained popularity over conventional gas infrared heaters. Catalytic infrared heaters are simple in design and work on a diffusion process in which gas and air meet at a catalyst surface sandwiched between two layers in counter diffusion mode. The heaters produce an energy flux of 2100 to 6,000 Btulhr/ft2 at 500°F to 950°F surface temperature.

Catalytic infrared heaters produce a flameless heat distributed over a wide range of wave lengths. Most significantly, catalytic heaters produce heat in the longer wavelength zone that is most desirable in heating organic material or in evaporating water. Some of the  most salient features of this type of heater are

  • Flameless oxidation

  • No flashback

  • No exterior blower required

  • No significant heat loss from the housing

  • No Nox and an insignificant amount of other combustibles

  • Insignificant sensible heat loss

  • No fear of a VOC explosion due to flameless heat

  • Higher thermal efficiency

Compared to conventional gas radiant heaters, catalytic infrared heaters can be much safer to use in a wide variety of applications.

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Vulcan Catalytic Systems, Ltd. | 300 Highpoint Ave., Portsmouth, RI 02871 | 401-683-2070
Email: jmartin@vulcan-mdf.com