Sampling was carried out at Site B on 26-28 September 2002. Samples were collected from the swarf baghouse stack, wheel melt baghouse and furnace 2 discharges to determine the concentration and mass emission of PCDD and PCDF present in the gases discharged to the atmosphere.
4.1 Introduction
The sample point was located in the stack exiting from the swarf baghouse stack. The sample point is more than 8 diameters downstream and approximately 3 diameters upstream from any disturbance to flow.
Two sample points had been installed for sampling particulate. However, these were not suitable for dioxin sampling due to restricted access. One additional port was added for dioxin sampling.
Details of the sampling times and stack dimensions are:
- Sampling time: 8:57-12:57
- Stack dimensions: 0.7 metre diameter circular duct.
4.2 Results
4.2.1 Swarf drier
Table 4.1: Stack gas conditions at the swarf baghouse stack sampling point
| CO2 | Temperature(°C) | Moisture(%) | Velocity(m/s) | Flow rate | ||
|---|---|---|---|---|---|---|
| (%, wet) | (%, dry) | (m3/s) | (m3/s, 0°C, 1 Atm, dry) | |||
| 1.8 | 1.8 | 94.0 | 2.4 | 9.3 | 3.6 | 2.6 |
Table 4.2: Results of isokinicity for swarf baghouse stack
| Sample | Actual sample volume (m3, 0°C, 1 Atm, dry) | Calculated sample volume (m3, 0°C, 1 Atm, dry) | Isokinicity (%) |
|---|---|---|---|
| 1 | 3.8996 | 3.7368 | 104% |
All samples are within the required isokinicity range of 100 ± 10%
Table 4.3: Average combustion gas results for swarf baghouse stack
| CO (mg/m3) | SO2 (mg/m3) | NO (mg/m3) | O2 (%) | NO2 (mg/m3) |
|---|---|---|---|---|
| < 11 | < 25 | 17.7 | 18.7 | <9 |
The weight of scrap metal melted during this sample was 4 tonnes.
Table 4.4: Summary results from swarf baghouse stack
| Concentration (ng/m3) | Emission (ng/hr) | Emission (ng/tonne) | ||
|---|---|---|---|---|
| Sum of PCDD and PCDF congeners | Excluding LOD values | 1.64 | 15,315 | 15,315 |
| Including half LOD values | 1.64 | 15,315 | 15,315 | |
| Including LOD values | 1.64 | 15,315 | 15,315 | |
| Total I-TEQ | Excluding LOD values | 0.0199 | 186 | 186 |
| Including half LOD values | 0.0210 | 196 | 196 | |
| Including LOD values | 0.0222 | 207 | 207 | |
| Total WHO-TEQ | Excluding LOD values | 0.0203 | 189 | 189 |
| Including half LOD values | 0.0214 | 200 | 200 | |
| Including LOD values | 0.0226 | 211 | 211 |
Table 4.5: Results from swarf baghouse stack (individual congeners)
View results from swarf baghouse stack (individual congeners) (large table)
4.2.2 Wheel melt furnace
The sample point was located in the stack exiting from the wheel melt baghouse stack. The sample point is more than 8 diameters downstream and approximately 3 diameters upstream from any disturbance to flow.
Two sample points had been installed for sampling particulate. However, these were not suitable for dioxin sampling due to restricted access. One additional port was added for dioxin sampling.
Details of the sampling date, times and stack dimensions are:
- Sample date and time: 27 September 2002, 11:29-15:32
- Stack dimensions: 0.60 metre diameter circular duct.
Table 4.6: Particulate emissions from wheel melt baghouse stack
| Sample | Sample mass (g) | Particulate emissions | |
|---|---|---|---|
| (mg/m3, dry, 0°C, 1 Atm) | (kg/h) | ||
| 1 | 0.0001 | 0.02 | 0.00021 |
Note: The sample mass is below the limit of detection.
Table 4.7: Average stack gas conditions at the wheel melt baghouse stack sampling point
| CO2 | Temperature(°C) | Moisture(%) | Velocity(m/s) | Flow rate | ||
|---|---|---|---|---|---|---|
| (%, wet) | (%, dry) | (m3/s) | (m3/s, 0°C, 1 Atm, dry) | |||
| <0.5 | <0.5 | 63.0 | 0.7 | 11.0 | 3.5 | 2.8 |
Table 4.8: Results of isokinicity for wheel melt baghouse stack
| Sample | Actual sample volume (m3, 0°C, 1 Atm, dry) | Calculated sample volume (m3, 0°C, 1 Atm, dry) | Isokinicity (%) |
|---|---|---|---|
| 1 | 4.7979 | 5.0816 | 94 |
All samples are within the required isokinicity range of 100 ± 10%.
Table 4.9: Combustion gas results
| CO (mg/m3) | SO2 (mg/m3) | NO (mg/m3) | O2 (%) | NO2 (mg/m3) |
|---|---|---|---|---|
| < 11 | < 25 | < 12 | 21.1 | <9 |
The weight of scrap metal melted during this sample was 5.487 tonnes.
Table 4.10: Summary results from wheel melt baghouse stack
| Concentration (ng/m3) | Emission (ng/hr) | Emission (ng/tonne) | ||
|---|---|---|---|---|
| Sum of PCDD and PCDF congeners | Excluding LOD values | 0.00188 | 19.2 | 14.0 |
| Including half LOD values | 0.0132 | 136 | 99.0 | |
| Including LOD values | 0.0246 | 252 | 184 | |
| Total I-TEQ | Excluding LOD values | 0 | 0 | 0 |
| Including half LOD values | 0.000491 | 5.03 | 3.67 | |
| Including LOD values | 0.000981 | 10.1 | 7.34 | |
| Total WHO-TEQ | Excluding LOD values | 0 | 0 | 0 |
| Including half LOD values | 0.000588 | 6.04 | 4.40 | |
| Including LOD values | 0.00118 | 12.1 | 8.80 |
Table 4.11: Results from wheel melt baghouse stack (individual congeners)
View results from wheel melt baghouse stack (individual congeners) (large table)
4.2.3 Furnace 2
One sample point was located in a vertical section of stack approximately 4 diameters downstream and more than 4 diameters upstream from a disturbance to flow.
Details of the sampling date, times and stack dimensions are:
- Sample date and time: 26 September 2002, 11:04-15:58
- Stack dimensions: 1.43 metre diameter circular duct.
Table 4.12: Particulate emissions from furnace 2
| Sample | Sample mass (g) | Particulate emissions | ||
|---|---|---|---|---|
| (mg/m3, dry, 0°C, 1 Atm) | mg/m3 (dry, 0°C, 12% CO2) | (kg/h) | ||
| 1 | 0.0020 | 0.67 | 5.7 | 0.017 |
Table 4.13: Average stack gas conditions at the furnace 2 sampling point
| CO2 | Temperature(°C) | Moisture(%) | Velocity(m/s) | Flow rate | ||
|---|---|---|---|---|---|---|
| (%, wet) | (%, dry) | (m3/s) | (m3/s, 0°C, 1 Atm, dry) | |||
| 1.4 | 1.4 | 255 | 2.9 | 8.7 | 14.1 | 7.1 |
Table 4.14: Results of isokinicity for furnace 2
| Sample | Actual sample volume (m3, 0°C, 1 Atm, dry) | Calculated sample volume (m3, 0°C, 1 Atm, dry) | Isokinicity (%) |
|---|---|---|---|
| 1 | 2.9946 | 3.2262 | 93 |
All samples are within the required isokinicity range of 100 ± 10%.
Table 4.15: Average combustion gas results for furnace 2
| CO (mg/m3) | SO2 (mg/m3) | NO (mg/m3) | O2 (%) | NO2 (mg/m3) |
|---|---|---|---|---|
| < 11 | < 25 | 23.9 | 19.0 | <9 |
The weight of scrap metal melted during this sample was 1.952 tonnes.
Table 4.16: Summary results from induction furnace 2
| Concentration (ng/m3) | Concentration (ng/m3 11% O2) | Emission (ng/hr) | Emission (ng/tonne) | ||
|---|---|---|---|---|---|
| Sum of PCDD and PCDF congeners | Excluding LOD values | 0.00334 | 0.017 | 84.9 | 198 |
| Including half LOD values | 0.0172 | 0.086 | 437 | 1019 | |
| Including LOD values | 0.0311 | 0.16 | 790 | 1841 | |
| Total I-TEQ | Excluding LOD values | 0 | 0 | 0 | 0 |
| Including half LOD values | 0.00100 | 0.0050 | 25.3 | 59.0 | |
| Including LOD values | 0.00199 | 0.010 | 50.7 | 118 | |
| Total WHO-TEQ | Excluding LOD values | 0 | 0 | 0 | 0 |
| Including half LOD values | 0.00107 | 0.0054 | 27.3 | 63.6 | |
| Including LOD values | 0.00215 | 0.011 | 54.5 | 127 |
Table 4.17: Results from induction furnace 2 (individual congeners)
View results from induction furnace 2 (individual congeners) (large table)
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4 Site B
April 2004
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