3.1 Introduction
Sampling was carried out at Site A on 19 September 2002. Samples were collected from the arc furnace discharge to determine the concentration of PCDD and PCDF present in the gases discharged to the atmosphere.
There were two sample ports on the duct exiting the arc furnace. The sample ports were approximately five diameters down stream from any disturbance to the flow and approximately one diameter upstream from the exit to the flow. As such the ports were not ideal for sampling particulate matter.
Each duplicate was sampled from one port.
Details of the sampling times and stack dimensions are:
- sampling times: Samples 1 and 2 (duplicate sampling): 11:58-15:10
- stack dimensions: 0.57 x 0.53 metre rectangular duct.
3.2 Results
Table 3.1: Particulate emissions from arc furnace
| Sample | Sample mass (g) | Particulate emissions | |
|---|---|---|---|
| (mg/m3, dry, 0°C, 1 Atm) | (kg/h) | ||
| 1 | 0.0451 | 17.8 | 0.42 |
| 2 | 0.0281 | 7.3 | 0.20 |
| Average | 12.6 | 0.31 | |
Table 3.2: Average stack gas conditions at the arc furnace sampling point 1 (small hot box)
| CO2 | Temperature (°C) | Moisture (%) | Velocity (m/s) | Flow rate | ||
|---|---|---|---|---|---|---|
| (%, wet) | (%, dry) | (m3/s) | (m3/s, 0°C, 1 Atm, dry) | |||
| <0.5 | <0.5 | 25.8 | 1.3 | 24.1 | 7.3 | 6.6 |
Table 3.3: Average stack gas conditions at the arc furnace sampling point 2 (large hot box)
| CO2 | Temperature (°C) | Moisture (%) | Velocity (m/s) | Flow rate | ||
|---|---|---|---|---|---|---|
| (%, wet) | (%, dry) | (m3/s) | (m3/s, 0°C, 1 Atm, dry) | |||
| <0.5 | <0.5 | 25.8 | 1.2 | 27.6 | 8.3 | 7.5 |
Table 3.4: Results of isokinicity for arc furnace
| Sample | Actual sample volume (m3, 0°C, 1 Atm, dry) | Calculated sample volume (m3, 0°C, 1 Atm, dry) | Isokinicity (%) |
|---|---|---|---|
| 1 | 2.5333 | 2.7918 | 91% |
| 2 | 3.8386 | 4.1972 | 91% |
All samples are within the required isokinicity range of 100 ± 10%.
Table 3.5: Average combustion gas results
| CO (mg/m3) | SO2 (mg/m3) | NO (mg/m3) | O2 (%) | NO2 (mg/m3) |
|---|---|---|---|---|
| 54.5 | < 25 | 24.7 | 21.1 | <9 |
The weight of scrap metal melted during the sampling was 3.45 tonnes. This number was used for both samples as sampling occurred at the same time.
Table 3.6: Summary results from arc furnace sample 1 trap, rinses and filter
| Concentration (ng/m3) | Emission (ng/hr) | Emission (ng/tonne) | ||
|---|---|---|---|---|
| Sum of PCDD and PCDF congeners | Excluding LOD values | 0.609 | 14,381 | 13,339 |
| Including half LOD values | 0.649 | 15,313 | 14,203 | |
| Including LOD values | 0.688 | 16,245 | 15,068 | |
| Total I-TEQ | Excluding LOD values | 0.0118 | 279 | 259 |
| Including half LOD values | 0.0136 | 322 | 298 | |
| Including LOD values | 0.0154 | 365 | 338 | |
| Total WHO-TEQ | Excluding LOD values | 0.0140 | 330 | 306 |
| Including half LOD values | 0.0158 | 372 | 345 | |
| Including LOD values | 0.0175 | 414 | 384 |
Table 3.7: Results from arc furnace (individual congeners sample 1 trap, rinses and filter)
View results from arc furnace (individual congeners sample 1 trap, rinses and filter) (large table)
Table 3.8: Summary results from arc furnace sample 2 trap, rinses and filter
| Concentration (ng/m3) | Emission (ng/hr) | Emission (ng/tonne) | ||
|---|---|---|---|---|
| Sum of PCDD and PCDF congeners | Excluding LOD values | 1.06 | 28,515 | 26,448 |
| Including half LOD values | 1.06 | 28,515 | 26,448 | |
| Including LOD values | 1.06 | 28,515 | 26,448 | |
| Total I-TEQ | Excluding LOD values | 0.0218 | 590 | 547 |
| Including half LOD values | 0.0235 | 635 | 589 | |
| Including LOD values | 0.0252 | 681 | 632 | |
| Total WHO-TEQ | Excluding LOD values | 0.0240 | 648 | 601 |
| Including half LOD values | 0.0257 | 694 | 644 | |
| Including LOD values | 0.0274 | 740 | 686 |
Table 3.9: Results from arc furnace (individual congeners sample 2 trap, rinses and filter)
View results from arc furnace (individual congeners sample 2 trap, rinses and filter) (large table)
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3 Site A
April 2004
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