简介:SUMMARY OF METHOD
2.1 This method employs a sampling module and meter box to withdraw a 20-L sample of
effluent gas containing volatile organic compounds from a stationary source at a flow rate of 1 L/min,
using a gla简介:SUMMARY OF METHOD
2.1 This method employs a sampling module and meter box to withdraw a 20-L sample of
effluent gas containing volatile organic compounds from a stationary source at a flow rate of 1 L/min,
using a glass-lined probe heated to 130 ± 5EC and a sampling method for volatile organic
compounds (SMVOC) train.
2.2 The gas stream is cooled to 20EC by passage through a water-cooled condenser and
volatile organic compounds are collected on a set of sorbent traps (Tenax®-GC/Tenax®-
GC/Anasorb®-747). Liquid condensate is collected in an impinger placed between the two Tenax®-
GC traps and the Anasorb®-747 trap. The first and second traps contain 1.6 g of Tenax®-GC each
and the third trap (back trap) contains 5.0 g of Anasorb®-747. A total number of sorbent tube sets
to encompass a total sampling time of 2 hrs is collected: i.e., if a sampling rate of 1 L/min for 20
minutes is used, a total of six sorbent tube sets will be collected in 2 hr of sampling.
2.3 Alternative conditions for sample collection may be used, collecting a sample volume of
20 L or less at a flow rate reduced from 1 L/min. (Operation of the SMVOC under these conditions
is referred to as SLO-SMVOC.) The SLO-SMVOC may be used to collect 5 L of sample (0.25
mL/min for 20 min) or 20 L of sample (0.5 L/min for 40 min) on each set of sorbent tubes. These
smaller sample volumes collected at lower flow rates should be considered when the boiling points
of the volatile organic compounds of interest are below 0EC (see Table 1) to prevent breakthrough.
Refer to Sec. 2.2 for the total number of tube sets collected per run.详细>