Other significant air emissions (ton)
66
0
1,000
2,000
3,000
4,000
5,000
1,023.0
1,444.5
16.1 2.7 57.7 19.2
222.9 239.2
5.1 7.4 157.7 110.1
4,330.5
3,553.9
Nox
Sox
N
2
0
CH
4
Fluoride
emissions
PFC’s
Particles
2011
2012
Calculation methods for ΝΟx, SOx and Dust emissions
Nevertheless, the environmental strat-
egy of MYTILINEOS Group comprises
key initiatives that focus on improv-
ing our performance relating to green-
house gas and CO
2
emissions over the
next years. These include the follow-
ing:
The most extensive possible use of
natural gas as the primary fuel in-
stead of oil in aluminium production,
with ALUMINIUM S.A. already mak-
ing efforts to optimise the use of
lime (purchase/production).
In the Energy sector, PROTERGIA
S.A. by selecting natural gas as the
In the Metallurgy sector (aluminium production):
Α. Dust:
Dust concentration in the plant’s point emission sources is meas-
ured as follows: (a) By isokinetic sampling, with a frequency of four
samplings per year at the plant’s Α070, FLN, H15, H1, H28 chim-
neys; (b) using continuous measurement analysers at the anodes
kiln, revolving and static components and lime kiln furnaces; and
(c) by isokinetic sampling, with monthly samplings at the no. 1-2
and no.3-4 Gas Treatment Centres for the electrolysis gases. For
calculating the quantities of annual emissions in tons, the following
were used: (a) For point sources where isokinetic sampling is used,
the average of the four concentration values (in mg/Nm3) and of
the flow rate (in Nm3/s); and (b) for point sources where contin-
uous measurement is used, the average of the daily concentration
values (in mg/Nm3) and of the flow rate (in Nm3/s) from the iso-
kinetic samplings of all years for which these are available.
Β. ΝΟx:
Annual emissions of nitrogen oxides refer only to fuel consump-
tion (fuel oil) and were calculated stoichiometrically, using an emis-
sion factor of 5.363 g/kg of fuel (Guide to Energy Investments, Min-
istry of Development, 2005). NOx emissions from processes are not
measured or calculated (no official method is available yet).
C. SO
2
:
Annual sulphur dioxide emissions refer only to fuel consumption
(fuel oil) and are calculated based on its sulphur content as this is
shown on the chemical analysis sheets. Sulphur dioxide emissions
from the anodes baking process are not calculated (no verifiable
method is available).
In the Energy sector:
In the case of the power production plants of PROTERGIA S.A., be-
cause of the quality of the consumed fuel (natural gas), no emis-
sion limit values apply for SO
2
and particle emissions (in accordance
with the Environmental Terms Approval Decisions in force for these
plants, and under the applicable Community and Greek law on air
emissions from combustion plants). Consequently, emission limit
values only apply for NOx (in this particular case, NO
2
) with the fol-
lowing acceptance limits:
- 50 mg/Nm3 (on a dry basis with 15% Ο
2
), for operation with a
load above 70%;
- 75 mg/Nm3 (on a dry basis with 15% Ο
2
), for operation with a
load above 70% and with an annual total electrical efficiency above
50%.
NOx levels are measured continuously by the plants’ CEMS and the values logged
are expressed in mg/Nm
3
. On the basis of inventory data, acceptance limits
were not exceeded.
