§ 63.1513
Equations for determining compliance.
(a) THC emission limit. Use Equation 6 to determine compliance with an emission limit for THC:

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Where,
E = Emission rate of measured pollutant, kg/Mg (lb/ton) of feed;
C = Measured volume fraction of pollutant, ppmv;
MW = Molecular weight of measured pollutant, g/g-mole (lb/lb-mole): THC (as propane) = 44.11;
Q = Volumetric flow rate of exhaust gases, dscm/hr (dscf/hr);
K1 = Conversion factor, 1 kg/1,000 g (1 lb/lb);
K2 = Conversion factor, 1,000 L/m3 (1 ft3/ft3);
Mv = Molar volume, 24.45 L/g-mole (385.3 ft3/lb-mole); and
P = Production rate, Mg/hr (ton/hr).
(b) PM, HCl and D/F emission limits. (1) Use Equation 7 of this section to determine compliance with an emission limit for PM or HCl:

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Where:
E = Emission rate of PM or HCl, kg/Mg (lb/ton) of feed;
C = Concentration of PM or HCl, g/dscm (gr/dscf);
Q = Volumetric flow rate of exhaust gases, dscm/hr (dscf/hr);
K1 = Conversion factor, 1 kg/1,000 g (1 lb/7,000 gr); and
P = Production rate, Mg/hr (ton/hr).
(2) Use Equation 7A of this section to determine compliance with an emission limit for D/F:

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Where:
E = Emission rate of D/F, µg/Mg (gr/ton) of feed;
C = Concentration of D/F, µg/dscm (gr/dscf);
Q = Volumetric flow rate of exhaust gases, dscm/hr (dscf/hr); and
P = Production rate, Mg/hr (ton/hr).
(c) HCl percent reduction standard. Use Equation 8 to determine compliance with an HCl percent reduction standard:

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Where,
%R = Percent reduction of the control device;
Li = Inlet loading of pollutant, kg/Mg (lb/ton); and
Lo = Outlet loading of pollutant, kg/Mg (lb/ton).
(d) Conversion of D/F measurements to TEQ units. To convert D/F measurements to TEQ units, the owner or operator must use the procedures and equations in “Interim Procedures for Estimating Risks Associated with Exposures to Mixtures of Chlorinated Dibenzo-p-Dioxins and -Dibenzofurans (CDDs and CDFs) and 1989 Update” (EPA-625/3-89-016), incorporated by reference in § 63.1502 of this subpart, available from the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, Virginia, NTIS no. PB 90-145756.

(e) Secondary aluminum processing unit. Use the procedures in paragraphs (e)(1), (2), and (3) or the procedure in paragraph (e)(4) of this section to determine compliance with emission limits for a secondary aluminum processing unit.

(1) Use Equation 9 to compute the mass-weighted PM emissions for a secondary aluminum processing unit. Compliance is achieved if the mass-weighted emissions for the secondary aluminum processing unit (EcPM) is less than or equal to the emission limit for the secondary aluminum processing unit (LcPM) calculated using Equation 1 in § 63.1505(k).

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Where,
EcPM = The mass-weighted PM emissions for the secondary aluminum processing unit;
EtiPM = Measured PM emissions for individual emission unit i;
Tti = The average feed rate for individual emission unit i during the operating cycle or performance test period; and
n = The number of emission units in the secondary aluminum processing unit.
(2) Use Equation 10 to compute the aluminum mass-weighted HCl emissions for the secondary aluminum processing unit. Compliance is achieved if the mass-weighted emissions for the secondary aluminum processing unit (EcHCl) is less than or equal to the emission limit for the secondary aluminum processing unit (LcHCl) calculated using Equation 2 in § 63.1505(k).

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Where,
EcHCl = The mass-weighted HCl emissions for the secondary aluminum processing unit; and
EtiHCl = Measured HCl emissions for individual emission unit i.
(3) Use Equation 11 to compute the aluminum mass-weighted D/F emissions for the secondary aluminum processing unit. Compliance is achieved if the mass-weighted emissions for the secondary aluminum processing unit is less than or equal to the emission limit for the secondary aluminum processing unit (LcD/F) calculated using Equation 3 in § 63.1505(k).

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Where,
EcD/F = The mass-weighted D/F emissions for the secondary aluminum processing unit; and
EtiD/F = Measured D/F emissions for individual emission unit i.
(4) As an alternative to using the equations in paragraphs (e)(1), (2), and (3) of this section, the owner or operator may demonstrate compliance for a secondary aluminum processing unit by demonstrating that each existing group 1 furnace is in compliance with the emission limits for a new group 1 furnace in § 63.1505(i) and that each existing in-line fluxer is in compliance with the emission limits for a new in-line fluxer in § 63.1505(j).

[65 FR 15710, Mar. 23, 2000, as amended at 69 FR 53984, Sept. 3, 2004]