S.L. 549.56 Art. 10Multi-firing units. S.L. 549.77

(1) Permits for combustion plants made up of multifiring units involving the simultaneous use of two or more fuels shall include conditions relating to compliance with emission limit values which shall be established as follows:

(a) by taking the emission limit value relevant to each individual fuel and pollutant corresponding to the rated thermal input of the combustion plant as given in Schedules I, II, III, IV, V, VI and VII;

(b) by determining fuel-weighted emission limit values, which are obtained by multiplying the above individual emission limit value by the thermal input delivered by each fuel, the product of multiplication being divided by the sum of the thermal inputs delivered by all fuels; and

(c) by aggregating the fuel-weighted limit values.

(2) In multi-firing units using distillation and conversion residues from crude-oil refining for own consumption, alone or with other fuels, the provisions for the fuel with the highest emission limit value (determinative fuel) shall apply notwithstanding sub-regulation (1) of this regulation, if during the operation of the combustion plant the proportion contributed by that fuel to the sum of the thermal inputs delivered by all fuels is at least 50%. Where the proportion of the determinative fuel is lower than 50%, the emission limit value is determined on a pro rata basis of the heat input supplied by individual fuels in relation to the sum of the thermal inputs delivered by all fuels as follows:

(a) by taking the emission limit value relevant for each individual fuel and pollutant corresponding to the rated thermal input of the combustion plant as given in Schedules I, II, III, IV, V, VI and VII;

(b) by calculating the emission limit value of the determinative fuel (fuel with the highest emission limit value according to Schedules I, II, III, IV, V, VI and VII and in the case of two fuels having the same emission limit value, the fuel with the higher thermal input); this value is obtained by multiplying the emission limit value laid down in Schedules I, II, III, IV, V, VI and VII for that fuel by a factor of two, and subtracting from this product the emission limit value of the fuel with the lowest emission limit value;

(c) by determining the fuel-weighted emission limit values, which are obtained by multiplying the calculated fuel emission limit value by the thermal input of the determinative fuel and other individual emission limit values by the thermal input delivered by each fuel, the product of multiplication being divided by the sum of the thermal inputs delivered by all fuels; and

(d) by aggregating the fuel-weighted emission limit values.

(3) As an alternative to sub-regulation (2), the following average emission limit values for sulphur dioxide may be applied (irrespective of the fuel combination used):

(a) for the plants referred to in regulations 3(1) and 4(1): -3 1000 mg SO .Nm , averaged all over such plants 2 within the refinery; and

(b) for the ‘new’ plants referred to in regulation 3(2): 600 mg SO .Nm-3, averaged all over such plants within the 2 refinery, with the exception of gas turbines: Provided that the competent authority shall ensure that the application of this provision does not lead to an increase in emissions from existing plants.

(4) In the case of combustion plants with multifiring units involving the alternative use of two or more fuels, the emission limit values to be included in the permit shall be those in Schedules I, II, III, IV, V, VI and VII corresponding to each fuel used.

(5) The emission limit values determined according to the procedures prescribed by sub-regulations (1) to (4) are the highest permissible limit values. Permits issued under regulation 4 of Integrated Pollution Prevention and Control Regulations may include stricter emission limit values, particularly in order to ensure compliance with the BAT requirement.