Section 218

Section 218.APPENDIX C Reference Methods and Procedures

Introduction

This Appendix presents the reference methods and procedures required for implementing Reasonably Available Control Technology (RACT). Methods and procedures are identified for two types of RACT implementation:

a) Determination of VOM destruction efficiency for evaluating compliance with the 98 weight percent VOM reduction or 20 ppmv emission limit specified in Sections 218.520 through 218.527 of this Part; and

b) Determination of offgas flowrate, hourly emissions and stream net heating value for calculating TRE.

All reference methods identified in this Appendix refer to the reference methods specified at 40 CFR 60, Appendix A, incorporated by reference in Section 218.112 of this Part.

VOM DESTRUCTION EFFICIENCY DETERMINATION

The following reference methods and procedures are required for determining compliance with the percent destruction efficiency specified in Sections 218.520 through 218.527 of this Part.

a) Reference Method 1 or 1A for selection of the sampling site. The control device inlet sampling site for determination of vent stream molar composition or total organic compound destruction efficiency shall be prior to the inlet of any control device and after all recovery devices.

b) Reference Methods 2, 2A, 2C or 2D for determination of the volumetric flowrate.

c) Reference Method 3 to measure oxygen concentration of the air dilution correction. The emission sample shall be corrected to 3 percent oxygen.

d) Reference Method 18 to determine the concentration of total organic compounds (minus methane and ethane) in the control device outlet and total organic compound reduction efficiency of the control device.

TRE DETERMINATION

The following reference methods and procedures are required for determining the offgas flowrate, hourly emissions, and the net heating value of the gas combusted to calculate the vent stream TRE.

a) Reference Method 1 or 1A for selection of the sampling site. The sampling site for the vent stream flowrate and molar composition determination prescribed in (b) and (c) shall be prior to the inlet of any combustion device, prior to any post-reactor dilution of the stream with air and prior to any post-reactor introduction of halogenated compounds into the vent stream. Subject to the preceding restrictions on the sampling site, it shall be after the final recovery device. If any gas stream other than the air oxidation vent stream is normally conducted through the recovery system of the affected facility, such stream shall be rerouted or turned off while the vent stream is sampled, but shall be routed normally prior to the measuring of the initial value of the monitored parameters for determining compliance with the recommended RACT. If the air oxidation vent stream is normally routed through any equipment which is not a part of the air oxidation process as defined in 35 Ill. Adm. Code 211.350, such equipment shall be bypassed by the vent stream while the vent stream is sampled, but shall not be bypassed during the measurement of the initial value of the monitored parameters for determining compliance with Subpart V.

b) The molar composition of the vent stream shall be determined using the following methods:

1) Reference Method 18 to measure the concentration of all organics, including those containing halogens, unless a significant portion of the compounds of interest are polymeric (high molecular weight), can polymerize before analysis or have low vapor pressures, in which case Reference Method 25(a) shall be used.

2) ASTM D1946-67 (reapproved 1977), incorporated by reference in Section 218.112 of this Part, to measure the concentration of carbon monoxide and hydrogen.

3) Reference Method 4 to measure the content of water vapor, if necessary.

c) The volumetric flowrate shall be determined using Reference Method 2, 2A, 2C or 2D, as appropriate.

d) The net heating value of the vent stream shall be calculated using the following equation:

Where:

H	=	Net heating value of the sample, MJ/ppm, where the net enthalpy per mole of offgas is based on combustion at 25° C and 760 mmHg, but the standard temperature for determining the volume corresponding to one mole is 20° C, as in the definition of F (vent stream flowrate) below
K	=	Constant, 1.740 X 10^-7 (1/ppm) (mole/scm) (MJ/kcal) where standard temperature for mole/scm is 20° C
C_i	=	Concentration of sample component i, reported on a wet basis, in ppm, as measured by Reference Method 18 or ASTM D1946-67 (reapproved 1977), incorporated by reference in Section 218.112 of this Part.
H_i	=	Net heat of combustion of sample component i, kcal/mole based on combustion at 25° C and 760 mmHg. If published values are not available or cannot be calculated, the heats of combustion of vent stream components are required to be determined using ASTM D2382-76, incorporated by reference in Section 218.112 of this Part.

e) The emission rate of total organic compounds in the process vent stream shall be calculated using the following equation:

E	=	Emission rate of total organic compounds (minus methane and ethane) in the sample in kg/hr;
K	=	Constant, 2.494 X 10^-6 (1/ppm) (mole/scm) (kg/g) (min/hr), where standard temperature for mole/scm is 20° C;
M_i	=	Molecular weight of sample component I (g/mole)
F	=	Vent stream flow rate (scm/min), at a standard temperature of 20° C.

f) The total vent stream concentration (by volume) of compounds containing halogens (ppmv, by compound) shall be summed from the individual concentrations of compounds containing halogens which were measured by Reference Method 18.

(Source: Amended at 18 Ill. Reg. 16950, effective November 15, 1994)