Study on the Influence of Industrial Coke Oven Size on the Quality of Metallurgical Coke
<p>Schematic diagram of the large-scale supporting thermal balance device.</p> "> Figure 2
<p>Variation of coke thermal strength CSR<sub>25</sub> at multi-temperatures with reaction temperature <span class="html-italic">T</span>.</p> "> Figure 3
<p>The difference between the thermal strength values of the two cokes under multi-temperature conditions as well as their variation with the reaction temperature <span class="html-italic">T</span>.</p> "> Figure 4
<p>The optical anisotropy index (OTI) of coke samples.</p> "> Figure 5
<p>The XRD patterns of coke samples.</p> "> Figure 6
<p>The micro-pore size distribution of coke samples.</p> "> Figure 7
<p>Adsorption and desorption isotherms of coke samples.</p> "> Figure 8
<p>The nano-pore size distribution of coke samples.</p> ">
Abstract
:1. Introduction
2. Materials and Methods
2.1. Blending Coal and Coking Test
2.2. Determination of Coke Conventional Quality Indexes
2.3. Determination of Coke Thermal Strength at Multiple Temperatures
2.4. Characterization of Coke Microstructure
2.4.1. Carbon Structure
2.4.2. Pore Structure
3. Results and Discussion
3.1. Influence on the Conventional Coke Quality Indexes
3.2. Influence on the Coke Thermal Strength Indexes at Multiple Temperatures
3.3. Influence on the Carbon Structure
3.3.1. Optical Texture
3.3.2. Microcrystalline Structure
3.4. Influence on the Pore Structure
3.4.1. Micro-Pore Structure
3.4.2. Nano-Pore Structure
3.5. Discussion
4. Conclusions
- The conventional quality indexes show that the cold and thermal strengths of Coke-7m are higher than those of Coke-6m, indicating that the large-capacity coke oven plays a role in improving the quality of metallurgical coke;
- The thermal strength indexes at multiple temperatures show that the large-capacity coke oven obviously improves the thermal strength when coke solution loss tends to the “uniform reaction model” or “unreacted core model” at low or high temperatures but has little effect on the thermal strength when coke solution loss tends to the “gradient reaction model” at medium temperatures;
- Regarding carbon structure, the optical texture results show that Coke-7m has a higher content of coarse mosaic texture and fibrous texture; the microcrystalline structure results show that Coke-7m has a larger size and denser microcrystalline structure. The existence of advantages in carbon structure may be an important reason for the better macroscopic quality of metallurgical coke refined by large-capacity coke ovens;
- The industrial coke oven size has little influence on the pore structure of metallurgical coke. The micro-pore structure of Coke-7m is similar to that of Coke-6m, and the nano-pore structure is even more developed than that of Coke-6m.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Coal Type | Ratio (%) | Source |
---|---|---|
Gas coal | 9 | Shandong, China |
1/3 coking coal | 8 | Henan, China |
Fat coal | 25 | Shanxi, China |
Coking coal | 44 | Shanxi, China |
Lean coal | 14 | Shanxi, China |
Total | 100 |
Name | Proximate Analysis, wt % | St,d (%) | Rmax (%) | Thermoplastic Indexes | Bulk Density (t/m3) | Fineness (%) | ||||
---|---|---|---|---|---|---|---|---|---|---|
Mt | Ad | Vdaf | FCad | G | Y (mm) | |||||
Blending coal | 11.64 | 9.68 | 26.60 | 64.40 | 0.90 | 1.32 | 71.53 | 16.75 | 0.75 | 70 |
Coke Sample | Proximate Analysis, wt % | St,d (%) | ||
---|---|---|---|---|
Mad | Ad | Vdaf | ||
Coke-6m | 0.41 | 12.28 | 1.19 | 0.84 |
Coke-7m | 0.37 | 12.25 | 1.14 | 0.82 |
Coke Sample | M40 (%) | M10 (%) |
---|---|---|
Coke-6m | 87.08 | 6.41 |
Coke-7m | 88.90 | 5.20 |
Coke Sample | CRI (%) | CSR (%) |
---|---|---|
Coke-6m | 23.48 | 66.03 |
Coke-7m | 22.63 | 67.90 |
Coke Sample | CSR25 (%) | |||||
---|---|---|---|---|---|---|
1050 °C | 1100 °C | 1150 °C | 1200 °C | 1250 °C | 1300 °C | |
Coke-6m | 66.17 | 64.01 | 57.76 | 59.22 | 61.57 | 63.37 |
Coke-7m | 68.86 | 65.53 | 58.11 | 59.62 | 61.65 | 64.56 |
Coke Sample | ΔCSR25 (%) | |||||
---|---|---|---|---|---|---|
1050 °C | 1100 °C | 1150 °C | 1200 °C | 1250 °C | 1300 °C | |
Coke-6m | +2.16 | 0 | −6.25 | −4.79 | −2.44 | −0.64 |
Coke-7m | +3.33 | 0 | −7.42 | −5.91 | −3.88 | −0.97 |
Coke Sample | Content of Different Optical Textures (vol. %) | |||||||
---|---|---|---|---|---|---|---|---|
Isotropic Texture | Fine Mosaic Texture | Medium Mosaic Texture | Coarse Mosaic Texture | Incompletely Fibrous Texture | Completely Fibrous Texture | Leaflet Texture | Fusinite and Fragmental Texture | |
Coke-6m | 2.9 | 12.7 | 56.0 | 2.7 | 0.0 | 0.0 | 2.0 | 23.7 |
Coke-7m | 1.8 | 10.2 | 47.8 | 9.5 | 0.7 | 1.7 | 0.7 | 27.6 |
Optical Texture Type | Assignment |
---|---|
Isotropic texture | 0.0 |
Fine mosaic texture | 1.0 |
Medium mosaic texture | 1.5 |
Coarse mosaic texture | 2.0 |
Incompletely fibrous texture | 2.5 |
Completely fibrous texture | 3.0 |
Leaflet texture | 4.0 |
Fusinite and fragmental texture | 0.0 |
Coke Sample | Lc (nm) | La (nm) | d002 (nm) |
---|---|---|---|
Coke-6m | 1.78 | 4.82 | 0.3419 |
Coke-7m | 1.90 | 4.99 | 0.3414 |
Coke Sample | Average Pore Size APS (μm) | Average Pore-Wall Thickness APWT (μm) | Porosity P (%) |
---|---|---|---|
Coke-6m | 87.31 | 59.30 | 60.66 |
Coke-7m | 87.06 | 59.54 | 59.94 |
Coke Sample | Specific Surface Area S (m2/g) | Pore Volume V (mm3/g) | Average Pore Size ͞r (nm) |
---|---|---|---|
Coke-6m | 2.00 | 5.20 | 10.40 |
Coke-7m | 4.13 | 9.80 | 9.49 |
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Hao, L.; Zhang, J.; Cheng, H.; Xiao, L.; Liao, F.; Hu, W. Study on the Influence of Industrial Coke Oven Size on the Quality of Metallurgical Coke. Processes 2024, 12, 1637. https://doi.org/10.3390/pr12081637
Hao L, Zhang J, Cheng H, Xiao L, Liao F, Hu W. Study on the Influence of Industrial Coke Oven Size on the Quality of Metallurgical Coke. Processes. 2024; 12(8):1637. https://doi.org/10.3390/pr12081637
Chicago/Turabian StyleHao, Liangyuan, Jianliang Zhang, Huan Cheng, Luying Xiao, Fei Liao, and Wenjia Hu. 2024. "Study on the Influence of Industrial Coke Oven Size on the Quality of Metallurgical Coke" Processes 12, no. 8: 1637. https://doi.org/10.3390/pr12081637