Handbook of Solvents - George Wypych - ChemTech - Ventech!

18.1 Measurement and estimation of solvents emission and odor 1217
Measuring point
chimney
2
3
4
Time
11.25 - 12.00
12.45 - 13.10
13.10 - 14.30
13.50 - 14.40
09.25 - 09.55
09.55 - 10.25
09.15 - 09.45
09.45 - 10.15
10.15 - 10.45
Volume flow,
Nm³/h
39 240
33 900
108 650
Carbon
concentration,
mgC/Nm³
72.4
56.3
56.3
48.2
56.3
64.3
112.5
152.8
160.8
(1) The odorant concentration does not refer to the times stated.
Mass flow, gC/h
2 841
2 209
2 209
1 634
1 908
2 180
12 223
16 602
17 471
Odorant
concentration (1) ,
GE/m³
91
87
93
100
115
98
213
Mass flow,
TGE/m³
4 151
3 969
4 242
3 747
4 309
12 837
27 900
The EU VOC Directive for plants for wood coating with a solvent consumption of 15 -
25 t/year requires an emission limit of 100 mg C/Nm³.
In the example, this is only met at chimneys 2 and 3.
As a parallel to these measurements, using activated carbon tubes and subsequent gas
chromatographic evaluation it was determined that the main components of VOCs were acetone,
ethyl acetate, toluene, butyl acetate, xylene, ethylbenzene (Table 18.1.6). Butyl acetate
and ethyl acetate were the main components in the respective solvent mixtures.
Table 18.1.6. Measured results for individual components at different measuring
points
MPC*
1
2
3
4
Acetone Ethyl acetate Toluene Butyl acetate Ethyl benzene Xylene
Conc a MF b Conc a MF b Conc a MF b Conc a MF b Conc a MF b Conc a MF b
6.5
4.5
11.0
4.5
-
-
9.0
5.5
229
158
432
176
-
-
978
597
15.5
11.0
24.5
9.0
4.5
15.5
20.0
27.0
546
387
961
353
152
525
2 173
2 933
9.0
5.5
14.5
6.5
2.0
5.5
9.0
18.0
317
194
569
255
68
186
978
1 956
15.5
11.0
24.5
14.5
3.5
8.0
17.0
37.0
545
387
961
569
118
271
1 847
4 020
1.0
1.0
1.0
-
0.5
1.0
2.0
3.5
352
352
39
-
17
34
217
380
4.2
2.5
6.5
-
2.0
5.5
8.0
17.0
158
88
255
-
68
186
869
1 847
*MPC = Measuring point chimney; a concentration in mg/Nm³; b MF = mass flow in g/h
2 nd Example: Emissions measured in a spray-room
The usual technique of measuring VOC emissions in plants by means of the FID according
to VDI 3481/page 3 has the shortcoming that individual components in the gas mixture
cannot be measured separately, but only determined as total carbon. Also the device
needs to be placed in the immediate vicinity of the measuring point and requires frequent
calibration.