rb bertomeu, S.L.

Pol. Ind. Fondo de Llitera, Par. 82-83

E-22520 Fraga, Huesca (Spain)

Tel.:  +34 974 47 48 04 

+34 630 43 08 43





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The energy yield of a steam boiler is always related to its ‘energy efficiency’ and is described in the following formula, assuming we ignore any possible heat loss through the boiler body (let us presume that it is very well insulated) :

Heat supplied by the fuel – Heat escaping with flue gases
Heat supplied by the fuel

This is not to be confused with the combustion yield, which refers to the relationship between actual heat produced by combustion and the theoretical heat supplied by the fuel (NCV).
Therefore, in this type of installation it is desirable to maintain:

  • Combustion of optimal quality in order to gain the optimal yield from the Calorific Value of the fuel (with a minimal presence of CO and of unburned HC in combustion gases).
  • Operation with the lowest possible excess of air in combustion, to ensure that the gases are at the highest possible temperature at the boiler intake (maximum coefficient of heat transmission) and that the lowest possible exhaust is released into atmosphere (minimising heat loss).
  • Heat exchangers free from soot and incrusted fouling, in order to prevent any loss in the capacity of heat exchange.

The further the fuel is from being ‘clean’, the greater the difficulty in maintaining the above points at optimal levels.Thus, by using natural gas it is relatively easy to achieve optimal levels, whereas the use of heavy fuel oil is a hindrance in this respect, and requires intensive cleaning maintenance on the installation to prevent a loss of production capacity or an increase in heat loss via the exhaust gases released into the atmosphere.

Specific additives for heavy fuel oil, light fuel oil and Diesel oil such as the various types produced by “rb bertomeu”, are designed to act simultaneously on the three key points by favouring and improving combustion with a low level of excess air, while altering the melting point of ashes, so that they are flakier, less adherents and more powdery. This helps to obtain maximal production with a saving in fuel of up to 8 %.

For further information on this subject, consult the following documents compiled by rb bertomeu (by clicking on the chosen title):
   · Encrustations in fuel oil steam boilers
   · “rb bertomeu” products and its aplications.
   · Dossier rb – Customer reference letters



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