Technical Committee Fuel Oils

Determination of relevant sulphur limit of domestic heating oil for the promotion of oil condensing boilers

Different oil condensing boilers, which were available on the German market, have been investigated in order to determine the relevant limit for sulphur content in domestic heating oil. Up to now, the condensate from oil condensing boilers has to be neutralized in many cases due to local legislation. The composition of the condensates from oil boilers came out to be similar to the condensate from gas condensing boilers, as long as the sulphur content of heating oil is below 100 mg/kg. As the neutralization of condensate from gas condensing boilers is usually not required up to 200 kW-boilers, there should be no technical reason for neutralization, as long as the sulphur content is below 100 mg/kg. However, boiler manufactures are convinced, that only if the sulphur content is as low as 50 mg/kg, it will be possible to develop reliable oil condensing boilers for a reasonable price. Calculations of the total energy consumption came to the result, that primary energy can be saved. The increase of efficiency on the boiler side has more influence than the energy needed for desulphurization.