Cerney S.A.U.

Recovery boilers for high-temperature gases with ash

This solution for heat recovery from incineration gases is the embodiment of CERNEY’s R&D.

The proposal we received from our customer –the prestigious firm Kalfrisa– was to recover thermal energy and cool the gases down to a temperature suitable for discharge into the atmosphere. Having now achieved these goals, the proposal has proven to be both profitable and environmentally friendly.


Treating these gases was complex due to both their extremely high temperature (>900ºC) and their composition, making it necessary to avoid corrosion or obstructions due to the accumulation of unburned material.


The following technical solutions were developed to overcome the issues raised in the project:

  • Ceramic compound for high temperatures: our recovery boilers are protected thanks to a ceramic compound installed in the high-temperature areas, thus thermally insulating and protecting the most sensitive parts of the boiler.
  • Customised equipment design: working with gases at such high temperatures means the boilers have a large transmission surface, which conditions their design and accessibility. This issue has been overcome by balancing speeds and offsetting convection, as well as providing suitably sized equipment in line with the location, with full accessibility for cleaning and for removing any unburned material.
  • Internal cleaning system using compressed air: a bespoke cleaning system based on high-pressure air pulses was incorporated in order to prevent the pipes from becoming blocked. This system can be configured for time-based operation or to work indirectly based on the degree of fouling, which can be ascertained from the gas output temperature.

At Cerney Boilers we seek effective solutions for each particular situation. If you need to provide a custom thermal engineering solution, do not hesitate to contact us.