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4.1.3 Particulate train operation. For each run, record the data required on the example sheet shown in Figure 5-2. Take readings at each sampling point, at least every 5 minutes, and when significant changes in stack conditions necessitate additional adjustments in flow rate. To begin sampling, position the nozzle at the first traverse point with the tip pointing directly into the gas stream. Immediately start the pump and adjust the flow to isokinetic conditions. Sample for at least 5 minutes at each traverse point; sam
pling time must be the same for each point. Maintain isokinetic sampling throughout the sampling period. Nomographs are available which aid in the rapid adjustment of the sampling rate without other computations. APTD-0576 details the procedure for using these nomographs. Turn off the pump at the conclusion of each run and record the final readings. Remove the probe and nozzle from the stack and handle in accordance with the sample recovery process described in section 4.2.
PLANT LOCATION OPERATOR
BAROMETRIC PRESSURE ASSUMED MOISTURE. % HEATER BOX SETTING. PROBE LENGTH, m. NOZZLE DIAMETER, in.
RUN NO. SAMPLE BOX NO. METER BOX NO. METER AH C FACTOR
PROBE HEATER SETTING
SCHEMATIC OF STACK CROSS SECTION
LEAVING SAMPLE BOX CONDENSER OR TEMPERATURE LAST IMPINGER.
GAS SAMPLE TEMPERATURE
AT DRY GAS METER
INLET OUTLET (Tm inl. OF ITm url. °F
VELOCITY HEAD (APs).
6.3 Volume of water vapor.
ana Vrata=vi (1) T)
4.3 Analysis. Record the data required on the example sheet shown in Figure 5–3. Handle each sample container as follows:
Container No. 1. Transfer the filter and any loose particulate matter from the sample container to a tared glass weighing dish, desiccate, and dry to a constant weight. Report results to the nearest 0.5 mg.
Container No. 2. Transfer the acetone washings to a tared beaker and evaporate to dryness at ambient temperature and pressure. Desiccate and dry to a constant weight. Report results to the nearest 0.5 mg.
Container No. 3. Weigh the spent silica gel and report to the nearest gram.
Use methods and equipment which have been approved by the Administrator to calibrate the orifice meter, pitot tube, dry gas meter, and probe heater. Recalibrate after each test series.
6.1 Average dry gas meter temperature and average orifice pressure drop. See data sheet (Figure 5–2).
6.2 Dry gas volume. Correct the sample volume measured by the dry gas meter to standard conditions (70° F., 29.92 inches Hg) by using Equation 5–1.
equation 5-2 where: Vwsta= Volume of water vapor in the gas
sample (standard conditions),
cu. ft. Vin= Total volume of liquid collected in
impingers and silica gel (see Fig
ure 5–3), ml. p11,0= Density of water, 1 g./ml. M1,0= Molecular weight of water, 18 lb./
conditions, 530° R.
ditions, 29.92 inches Hg.
where: Bwo =Proportion by volume of water vapor in the gas
stream, dimensionless. Vwatd=Volume of water in the gas sample (standard
conditions), cu. ft. V metd=Volume of gas sample through the dry gas meter
(standard conditions), cu. ft. 6.5 Total particulate weight. Determine the total particulate catch from the sum of the weights on the analysis data sheet (Figure 5-3).
equation 5-1 where: Vmeta= Volume of gas sample through the
dry gas meter (standard condi
tions), cu. ft. Vm= Volume of gas sample through the
dry gas meter (meter condi
tions), cu. ft. Tota= Absolute temperature at standard
conditions, 530° R.
meter, inches Hg
orifice meter, inches H,O. 13.6= Specific gravity of mercury. Pata= Absolute pressure at standard con
ditions, 29.92 inches Hg.
equation 5-4 where: c':=Concentration of particulate matter in stack
gas, gr./s.c.f., dry basis. Mo=Total amount of particulate matter collected,
mg. Vmetd=Volume of gas sample through dry gas meter V.
(standard conditions), cu. ft.
6.6.2 Concentration in lb./cu. ft.
-=2.205 x 10-6_M. mgtd
equation 5-5 where:
Mo=Total amount of particulate matter collected, Co=Concentration of particulate matter in stack
mg. gas, lb./s.c.f., dry basis.
Vm... =Volume of gas sample through dry gas meter 453,600=Mg/lb.
(standard conditions), cu. ft. 6.7 Isokinetic variation.
I=Percent of isokinetic sampling.
and silica gel (See Fig. 5-3), ml. PH,O=Density of water, 1 g./ml. R=Ideal gas constant, 21.83 inches Hg-cu. ft./lb.
mole-°R. M.,o=Molecular weight of water, 18 lb./lb.-mole. Vm=Volume of gas sample through the dry gas meter
(meter conditions), cu. ft. Tm=Absolute average dry gas meter temperature
(see Figure 5-2), °R. Pbar=Barometric pressure at sampling site, inches AH=Average pressure drop across the orifice (see
Fig. 5-2), inches H20.
Fig. 5-2), °R.
Equation 2-2, ft./sec. P.=Absolute stack gas pressure, inches Hg. An=Cross-sectional area of nozzle, sq. ft. 6.8 Acceptable results. The following range sets the limit on acceptable isokinetic sampling results: If 90%<I<110%, the results are acceptable,
otherwise, reject the results and repeat the test. 7. Reference. Addendum to Specifications for Incinerator Testing at Federal Facilities, PHS, NCAPC, Dec. 6, 1967.
Martin, Robert M., Construction Details of Isokinetic Source Sampling Equipment, Environmental Protection Agency, APTD-0581.
Rom, Jerome J., Maintenance, Calibration, and Operation of Isokinetic Source Sampling Equipment, Environmental Protection Agency, APTD-0576.
Smith, W. S., R. T. Shigehara, and W. F. Todd, A Method of Interpreting Stack Sampling Data, Paper presented at the 63d Annual Meeting of the Air Pollution Control Association, St. Louis, Mo., June 14-19, 1970.
Smith, W. S., et al., Stack Gas Sampling Improved and Simplified with New Equipment, APCA paper No. 67–119, 1967.
Specifications for Incinerator Testing at Federal Facilities, PHS, NCAPC, 1967.
Equation 5-6 METHOD 6-DETERMINATION OF SULFUR DIOXIDE
EMISSIONS FROM STATIONARY SOURCES 1. Principle and applicability.
1.1 Principle. A gas sample is extracted from the sampling point in the stack. The acid mist, including sulfur trioxide, is separated from the sulfur dioxide. The sulfur dioxide fraction is measured by the bariumthorin titration method.
1.2 Applicability. This method is applicable for the determination of sulfur dioxide emissions from stationary sources only when specified by the test procedures for determining compliance with New Source Performance Standards.
2.1.1 Probe-Pyrex 1 glass, approximately 5 to 6 mm. ID, with a heating system to prevent condensation and a filtering medium to remove particulate matter including sulfuric acid mist.
2.1.2 Midget bubbler-One, with glass wool packed in top to prevent sulfuric acid mist carryover.
2.1.3 Glass wool.
2.1.5 Drying tube-Packed with 6 to 16 mesh indicating-type silica gel, or equivalent, to dry the sample.
2.1.6 Valve-Needle valve, or equivalent, to adjust flow rate.
2.1.7 PumpLeak-free, vacuum type.
2.1.8 Rate meter-Rotameter or equivalent, to measure a 0-10 s.c.f.h. flow range.
2.1.9 Dry gas meter-Sufficiently accurate to measure the sample volume within 1%.
2.1.10 Pitot tube-Type S, or equivalent, necessary only if a sample traverse is required, or if stack gas velocity varies with time.
2.2 Sample recovery.
2.2.2 Polyethylene storage bottles-TO store impinger samples.
1 Trade names.
2.3.1 Pipettes--Transfer type, 5 ml. and 10 ml. sizes (0.1 ml. divisions) and 25 ml. size (0.2 ml. divisions).
2.3.2 Volumetric flasks—50 ml., 100 ml., and 1,000 ml.
2.3.3 Burettes-5 ml. and 50 ml.
3.1.2 Isopropanol, 80%-Mix 80 ml. of isopropanol with 20 ml. of distilled water.
3.1.3 Hydrogen peroxide, 3%—dilute 100 ml. of 30% hydrogen peroxide to 1 liter with distilled water. Prepare fresh daily.
3.2 Sample recovery.
3.3.3 Thorin indicator-1-(0-arsonophenylazo)-2-naphthol-3,6-disulfonic acid, disodium salt (or equivalent). Dissolve 0.20 g. in 100 ml. distilled water.
3.3.4 Barium perchlorate (0.01 N)-Dissolve 1.95 g. of barium perchlorate (Ba (C10,), 3H,O] in 200 ml. distilled water and dilute to 1 liter with isopropanol. Standardize with sulfuric acid. Barium chloride may be used.
3.3.5 Sulfuric acid standard (0.01 N)— Purchase or standardize to +0.0002 N against 0.01N NaOH which has previously been standardized against potassium acid phthalate (primary standard grade).
4.1.1 Preparation of collection train. Pour 15 ml. of 80% isopropanol into the midget bubbler and 15 ml. of 3% hydrogen peroxide into each of the first two midget impingers. Leave the final midget impinger dry. Assemble the train as shown in Figure 6–1. Leak check the sampling train at the sampling site by plugging the probe inlet and pulling a 10 inches Hg vacuum. A leakage rate not in excess of 1% of the sampling rate is acceptable. Carefully release the probe inlet plug and turn off the pump. Place crushed ice around the impingers. Add more ice during the run to keep the temperature of the gases leaving the last impinger at 70° F. or less.
4.1.2 Sample collection. Adjust the sample flow rate proportional to the stack gas velocity. Take readings at least every five minutes and when significant changes in stack conditions necessitate additional adjustments in flow rate. To begin sampling, position the tip of the probe at the first sampling point and start the pump. Sample proportionally throughout the run. At the conclusion of each run, turn off the pump and record the final readings. Remove the probe from the stack and disconnect it from the train. Drain the ice bath and purge the remaining part of the train by drawing clean ambient air through the system for 15 minutes.
4.2 Sample recovery. Disconnect the impingers after purging. Discard the contents of the midget bubbler. Pour the contents of the midget impingers into a polyethylene shipment bottle. Rinse the three midget impingers and the connecting tubes with dis