Table 1.
Comparison of Particle Detection Methods in High-Pressure Gas
Particle | Offline Method | Online Detection with a Decompression |
Principle | Collection of particle samples | Effect of throttling decompression |
Size | Particle size analyzer such as: | Online measurement devices |
| ① Coulter principle: multisizer 3 or 4e (Beckman Coulter, US) | Optics: Promo 2000 or 3000/Weles 3000 (PALAS GmbH, Germany) |
| ② Optics: Welas digital 1000 or 2000 (PALAS GmbH, Germany) TSI-3330 (TSI, US) |
| ③ Aerodynamics: TSI-3321 (TSI, US) |
Concentration | Based on particle mass | Based on particle size |
Table 2.
Parameters of the Device Depicted in Fig. 1
Parameters | Value |
Sampling nozzle diameter /mm | 6 |
Test gas flow /L/min |
|
OPC particle size range /μm | 0.5–40 |
Maximum of number concentration
|
|
Thickness of window /μm | 2 |
Power of light /W | 35 |
Pressure sensor accuracy /Pa |
|
Temperature sensor precision /°C |
|
Filter precision /μm | 0.3 |
Accuracy of flowrate controller /L | 1 |
Table 3.
Component and Content of Natural Gas in #1 and #2 Stations
Component |
|
|
|
|
|
Mol /% | 95.80 | 1.70 | 0.20 | 0.80 | 1.50 |
Molar mass | 16.04 | 30.07 | 42.08 | 44.01 | 28.01 |
Table 4.
Collected Particles Analyzed Via EDS and SEM
Content % | C | O | Na | Fe | Al | Si |
1# | 3.21 | 35.63 | 0.45 | 50.71 | 4.70 | 5.30 |
2# | 3.17 | 37.83 | 0.26 | 54.30 | 1.36 | 3.08 |
Table 5.
Volume Fraction and Refractive Index of Each Composition
Material | Chemical Formula | Volume Fraction/% | Refractive Index |
1# | 2# |
Iron oxide |
| 8 | 7 | 2.42 |
Goethite | FeO(OH) | 11 | 12 | 2.26 |
Quartz |
| 40 | 38 | 1.5 |
Plagioclase |
| 32 | 31 | 1.529 |
Siderite |
| 9 | 12 | 1.875 |
Table 6.
Comparison of Online and Offline Test Results
Station Number | Online Test Size Range /μm |
| Error/% |
Online | Offline |
1# | 0.56–19.82 | 16.81 | 255.89 | 93.4 |
1# | 0.56–19.82 | 17.43 | 255.24 | 93.2 |
1# | 0.56–19.82 | 17.62 | 259.85 | 93.2 |
1# | 0.56–19.82 | 18.38 | 274.30 | 93.3 |
1# | 0.56–19.82 | 19.51 | 299.38 | 93.5 |
2# | 0.56–19.82 | 6.82 | 72.25 | 90.6 |
2# | 0.56–19.82 | 6.98 | 71.02 | 90.2 |
2# | 0.56–19.82 | 4.95 | 55.30 | 91.0 |
2# | 0.56–19.82 | 7.69 | 82.30 | 90.7 |
2# | 0.56–19.82 | 14.88 | 149.65 | 90.1 |
2# | 0.56–19.82 | 11.39 | 113.78 | 90.0 |
2# | 0.56–19.82 | 8.73 | 90.23 | 90.3 |
2# | 0.56–19.82 | 11.21 | 112.35 | 90.0 |
2# | 0.56–19.82 | 6.56 | 71.30 | 90.8 |
Table 7.
Basic Parameters of the Optical System
Parameters | Value |
Refractive index at standard conditions (
) | 1.000444 |
Length between window 1 and 2
| 14200 (
) |
Divergent light angle
| 13 |
Thickness of glass window /mm | 2.0 |
Focused light spot diameter
| 82 |
Table 8.
Dynamic Model Results at Different Pressures (0.1 MPa, 2.36 MPa, 3.42 MPa, 5 MPa, 7 MPa, and 9 MPa)
P/MPa |
|
|
|
|
|
0.10 | 13.00 | 82 | 0.0 | 0 | 0.0 |
2.36 | 12.87 | 82 | 34.8 | 189 | −50.7 |
3.42 | 12.80 | 82 | 51.9 | 336 | −62.3 |
5.00 | 12.70 | 82 | 78.3 | 647 | −73.8 |
7.00 | 12.57 | 82 | 113.4 | 1254 | −82.4 |
9.00 | 12.42 | 82 | 150.6 | 2182 | −87.6 |
Table 9.
Fitting Formulas of the Original and Modified Particle Size under Different Gas Pressure in Fig. 9
Gas Pressure/MPa |
|
|
|
|
0.1 | 0 | 1 | 1 |
2.36 | 0.226 | 2.055 | 0.9999 |
3.42 | 0.372 | 2.176 | 0.9996 |
5 | 0.474 | 2.642 | 0.9998 |
7 | 0.672 | 3.243 | 0.9998 |
9 | 0.895 | 3.873 | 0.9997 |
Table 10.
Comparison of Modified Online and Offline Test Results
Station Number |
| Median Particle Size/μm |
Online Modification | Offline | Error/% | Online Modification | Offline | Error/% |
1# | 218.53 | 255.89 | 14.6 | 3.13 | 3.39 | 7.6 |
1# | 224.15 | 255.24 | 12.2 | 3.14 | 3.40 | 7.8 |
1# | 229.24 | 259.85 | 11.8 | 3.16 | 3.40 | 7.1 |
1# | 239.86 | 274.30 | 12.6 | 3.21 | 3.43 | 7.3 |
1# | 254.22 | 299.38 | 15.1 | 3.25 | 3.45 | 7.0 |
2# | 63.33 | 72.25 | 12.3 | 3.60 | 3.28 | 9.8 |
2# | 65.25 | 71.02 | 8.1 | 3.60 | 3.29 | 9.4 |
2# | 47.06 | 55.30 | 14.9 | 3.53 | 3.21 | 9.9 |
2# | 70.84 | 82.30 | 13.9 | 3.61 | 3.29 | 9.7 |
2# | 134.87 | 149.65 | 9.9 | 3.75 | 3.45 | 8.7 |
2# | 104.28 | 113.78 | 8.3 | 3.71 | 3.41 | 8.8 |
2# | 80.82 | 90.23 | 10.4 | 3.55 | 3.27 | 8.6 |
2# | 103.13 | 112.35 | 8.2 | 3.62 | 3.32 | 9.0 |
2# | 61.70 | 71.30 | 13.5 | 3.60 | 3.28 | 9.8 |