Forecasting Potential Resources of Humic Substances in the Ukrainian Lignite
Abstract
1. Introduction
- -
- -
- -
2. Materials and Methods
2.1. Materials
2.2. Methods
2.2.1. Extraction of Humic Acids from Lignite
2.2.2. Determination of Physicochemical and Technological Parameters
2.3. Development of a Mathematical Model and Determination of Humic Acid Yield Based on Lignite Characteristics
3. Results and Discussion
3.1. Database Creation
3.2. Development of the Regression Empirical Equation
3.3. Validation of the ESM Adequacy
3.4. Characteristics and Humic Acid Yields of Ukrainian Lignite
- -
- Lower moisture and ash content;
- -
- Lower volatile matter yield;
- -
- Higher oxygen and sulfur content.
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Abbreviations
A | Category A (detailed reserves)—fully explored reserves with their quantity, quality, and occurrence conditions determined with high accuracy. The data are obtained through detailed geological studies and production drilling; |
B | Category B (detailed reserves with certain clarifications)—reserves that have been explored more generally than Category A. They are also sufficiently studied but may require additional refinement during development |
C1 | Category C1 (preliminarily explored reserves)—reserves whose quantity and quality are assessed based on less detailed studies, but are still sufficiently reliable for development and exploitation. Additional geological investigations are required for more precise parameter determination in this category; |
C2 | Category C2 (inferred reserves)—reserves forecasted based on indirect data and geological analogies. These reserves have not yet been sufficiently explored and therefore represent a preliminary estimate requiring substantial additional investigation. |
Aa | Ash content on an air-dried (analytical) basis; |
Ad | Ash content on a dry basis; |
Std | Sulfur content on a dry basis; |
Va | Volatile matter yield on an air-dried (analytical) basis; |
Vaf | Volatile matter yield on an ash-free basis |
Vdaf | Volatile matter yield on a dry, ash-free basis; |
Qsdaf | Gross calorific value on a dry, ash-free basis; |
Qsaf | Gross calorific value on an as-received, ash-free basis; |
HAa | Humic acid yield on an air-dried (analytical) basis; |
HAaf | Humic acid yield on an ash-free basis; |
HAdaf | Humic acid yield on a dry, ash-free basis; |
Wa | Moisture content on an air-dried (analytical) basis; |
Cdaf | Carbon content on a dry, ash-free basis; |
Hdaf | Hydrogen content on a dry, ash-free basis; |
Sdaf | Sulfur content on a dry, ash-free basis; |
Ndaf | Nitrogen content on a dry, ash-free basis; |
Odaf | Oxygen content on a dry, ash-free basis. |
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Region | Recoverable Reserves, kt | Number of Deposits | |
---|---|---|---|
A + B + C1 | C2 | ||
Dnipropetrovsk Region (Ukrainian Shield, Central Uplift, Prydniprovsky Block) | 1,033,945 | 258,053 | 18 |
Dnipropetrovsk Region (Dnieper-Donets Basin, Southern Flank) | 286,699 | 0 | 3 |
Zhytomyr Region (Ukrainian Shield, Central Uplift, Volyn Block) | 10,884 | 0 | 2 |
Zakarpattia Region (Transcarpathian Intermountain Basin, Chop–Mukachevo Zone) | 38,745 | 0 | 4 |
Kirovohrad Region (Ukrainian Shield, Central Uplift, Kirovohrad Block) | 750,833 | 39,604 | 44 |
Kharkiv Region (Dnieper-Donets Coal-Bearing Area) | 389,985 | 0 | 1 |
Cherkasy Region (Vatutine Geological and Industrial District) | 82,225 | 1524 | 8 |
Total: | 2,593,316 | 299,181 | 80 |
Deposit Name | Sample No. | Wa, wt.% | Aa, wt.% | Ad, wt.% | Va, wt.% | Vdaf, wt.% | Sdt, wt.% | Qsdaf, Kkal/kg | HAa, wt.% | HAdaf, wt.% | Elemental Composition, wt.% | ||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cdaf | Hdaf | Sdaf | Ndaf | Odaf | |||||||||||
Mokrokalyhirske, Ukraine | 1 | 16.50 | - ** | 47.90 | - | 57.80 | 2.11 | - | - | 87.58 | 80.65 | 4.39 | 3.52 | 1.25 | 10.19 |
2 | 8.70 | - | 8.60 | - | 50.10 | 1.77 | - | - | 49.59 | 67.89 | 4.55 | 1.92 | 1.33 | 24.31 | |
3 | 30.40 | - | 36.40 | - | 69.70 | 2.72 | - | - | 82.86 | 60.58 | 4.82 | 3.64 | 1.29 | 29.67 | |
Average * | 18.53 | - | 30.97 | - | - | 2.20 | - | - | 73.34 | 69.71 | 4.59 | 3.03 | 1.29 | 21.39 | |
Chakwal, Pakistan | 4 | 4.32 | 56.40 | - | 19.81 | - | - | 3236 | 25.50 | - | 26.73 | 12.39 | 5.05 | 0.00 | 55.83 |
5 | 2.60 | 57.20 | - | 17.30 | - | - | 3021 | 27.40 | - | 20.03 | 0.37 | 0.01 | 0.00 | 79.59 | |
6 | 5.33 | 55.89 | - | 19.67 | - | - | 3074 | 25.30 | - | 30.38 | 2.75 | 18.57 | 0.00 | 48.30 | |
7 | 3.44 | 58.43 | - | 18.41 | - | - | 3381 | 25.40 | - | 31.01 | 5.27 | 38.26 | 0.00 | 25.43 | |
8 | 3.80 | 56.70 | - | 18.50 | - | - | 3256 | 27.10 | - | 14.70 | 1.69 | 13.04 | 0.00 | 70.57 | |
9 | 4.44 | 47.22 | - | 18.83 | - | - | 3188 | 28.30 | - | 22.38 | 17.46 | 0.00 | 0.00 | 60.16 | |
Arenas de Rey and Puentes de García Rodríguez, Spain | 10 | 9.60 | 5.40 | - | 46.40 | - | - | - | - | 47.90 | 60.91 | 4.15 | 6.35 | 0.88 | 27.71 |
11 | 7.70 | 32.20 | - | 32.20 | - | - | - | - | 50.70 | 61.36 | 5.20 | 3.33 | 0.77 | 29.34 | |
Thar, Pakistan | 12 | 23.00 | 14.00 | - | 34.00 | - | - | 3809 | 35.00 | - | - | - | - | - | - |
Xiaolongtan, China | 13 | 9.30 | - | 10.50 | - | 42.30 | - | - | - | 57.80 | 57.47 | 5.01 | 1.16 | 1.58 | 34.78 |
Wa, wt.%. | Ad, wt.% | Vdaf, wt.% | Elemental Composition, wt.% | ||||
---|---|---|---|---|---|---|---|
Cdaf | Hdaf | Ndaf | Sdaf | Odaf | |||
26.40 | 13.00 | 61.80 | 69.55 | 4.65 | 0.70 | 3.37 | 21.73 |
Deposit Name | Wa, wt.% | Aa, wt.% | Ad, wt.% | Sdt, wt.% | Vdaf, wt.% | Qsdaf, MJ/kg | Qaf, MJ/kg |
---|---|---|---|---|---|---|---|
Mokrokalyhirske lignite open-pit mine | 17.90 | 21.10 | 25.70 | 3.17 | 60.70 | 28.33 | 23.97 |
Morozivske deposit | 14.00–15.20 | 15.00–20.20 | 17.60–23.50 | 2.70–4.00 | 61.10–68.70 | 24.62–28.68 | 18.56–24.48 |
№ | Wa, wt.% | Vaf, wt.% | Qaf, kJ/kg | HAaf, wt.% |
---|---|---|---|---|
X1i | X2i | X3i | Yi | |
1 | 16.50 | 41.89 | 22,156 | 63.50 |
2 | 8.70 | 45.38 | 20,062 | 44.91 |
3 | 30.40 | 41.29 | 12,708 | 49.12 |
4 | 4.32 | 45.38 | 12,971 | 58.33 |
5 | 2.61 | 40.43 | 12,329 | 64.06 |
6 | 5.33 | 44.59 | 12,192 | 57.36 |
7 | 3.44 | 44.29 | 13,679 | 61.01 |
8 | 3.78 | 42.76 | 13,128 | 62.61 |
9 | 4.44 | 35.68 | 12,763 | 53.68 |
10 | 9.63 | 49.00 | 17,740 | 43.04 |
11 | 7.70 | 47.54 | 17,124 | 44.95 |
12 | 23.00 | 39.53 | 12,289 | 40.70 |
13 | 9.30 | 37.95 | 15,607 | 51.86 |
Sample No. | X1, wt.% | X2, wt.% | X3, kJ/kg | Y, wt.% | Yireg, wt.% | εi |
---|---|---|---|---|---|---|
1. | 16.50 | 41.89 | 22156 | 63.50 | 50.54 | 0.2565 |
2. | 8.70 | 45.38 | 20062 | 44.91 | 52.30 | 0.1412 |
3. | 30.40 | 41.29 | 12708 | 49.12 | 44.24 | 0.1103 |
4. | 4.32 | 45.38 | 12971 | 58.33 | 54.67 | 0.0669 |
5. | 2.61 | 40.43 | 12329 | 64.06 | 58.65 | 0.0922 |
6. | 5.33 | 44.59 | 12192 | 57.36 | 54.69 | 0.0489 |
7. | 3.44 | 44.29 | 13679 | 61.01 | 55.78 | 0.0938 |
8. | 3.78 | 42.76 | 13128 | 62.61 | 56.58 | 0.1065 |
9. | 4.44 | 35.68 | 12763 | 53.68 | 60.71 | 0.1158 |
10. | 9.63 | 49.00 | 17740 | 43.04 | 49.62 | 0.1327 |
11. | 7.70 | 47.54 | 17124 | 44.95 | 51.52 | 0.1275 |
12. | 23.00 | 39.53 | 12289 | 40.70 | 49.05 | 0.1702 |
13. | 9.30 | 37.95 | 15607 | 51.86 | 56.78 | 0.0867 |
Average relative approximation errors (ε) | 0.1192 |
Moisture Content, Wa, wt.% | Volatile Matter Content, Vaf, wt.% | Higher Heating Value, Qaf, kJ/kg | Calculated Content HA, HAreg, af, wt.% | HA Content, HAaf, wt.% | Relative Approximation Error, % |
---|---|---|---|---|---|
X1 | X2 | X3 | Yreg | Y | ε |
26.40 | 43.80 | 16458 | 44.56 | 48.33 | 7.80 |
No. | Region Name | HA Content | ||
---|---|---|---|---|
HAaf, wt.% | HAa, wt.% | HAdaf, wt.% | ||
1 | Dnipropetrovsk Region (Dnieper-Donets Basin, Southern Flank) | 52.77–55.83 | 38.52–49.46 | 59.13–62.72 |
2 | Dnipropetrovsk Region (Ukrainian Shield, Central Uplift, Prydniprovsky Block) | 44.03–45.92 | 35.44–40.44 | 51.18–74.57 |
3 | Zhytomyr Region (Ukrainian Shield, Central Uplift, Volyn Block) | 47.34–47.42 | 36.40–37.30 | 56.19–62.01 |
4 | Zakarpattia Region (Transcarpathian Intermountain Basin, Chop–Mukachevo Zone) | 45.91–49.19 | 35.77–37.87 | 52.87–62.03 |
5 | Kirovohrad Region (Ukrainian Shield, Central Uplift, Kirovohrad Block) | 40.86–48.48 | 31.54–40.05 | 47.36–62.72 |
6 | Kharkiv Region (Dnieper-Donets Coal-Bearing Area) | 44.94–47.14 | 32.53–41.05 | 52.57–56.72 |
7 | Cherkasy Region (Vatutine Geological and Industrial District) | 43.17–51.59 | 31.15–42.95 | 46.11–58.63 |
HA Name | Wa, wt.% | Ad, wt.% | Vdaf, wt.% | Elemental Composition, wt.% | ||||
---|---|---|---|---|---|---|---|---|
Cdaf | Hdaf | Ndaf | Sdaf | Odaf | ||||
From Sample No. 1 of the Mokrokalyhirske lignite open-pit mine | 8.50 | 13.50 | 43.20 | 63.13 | 3.90 | 1.46 | 4.20 | 27.31 |
From Sample No. 2 of the Mokrokalyhirske lignite open-pit mine | 5.30 | 8.20 | 41.00 | 58.20 | 3.70 | 3.80 | 3.13 | 31.17 |
From Sample No. 3 of the Mokrokalyhirske lignite open-pit mine | 12.10 | 11.00 | 55.80 | 63.81 | 3.70 | 1.23 | 0.76 | 30.50 |
From the Morozivske deposit sample | 8.00 | 4.30 | 50.30 | 62.30 | 3.86 | 0.79 | 4.79 | 28.26 |
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Share and Cite
Pyshyev, S.; Miroshnichenko, D.; Shved, M.; Riznyk, V.; Bilushchak, H.; Borisenko, O.; Miroshnychenko, M.; Lypko, Y. Forecasting Potential Resources of Humic Substances in the Ukrainian Lignite. Resources 2025, 14, 117. https://doi.org/10.3390/resources14080117
Pyshyev S, Miroshnichenko D, Shved M, Riznyk V, Bilushchak H, Borisenko O, Miroshnychenko M, Lypko Y. Forecasting Potential Resources of Humic Substances in the Ukrainian Lignite. Resources. 2025; 14(8):117. https://doi.org/10.3390/resources14080117
Chicago/Turabian StylePyshyev, Serhiy, Denis Miroshnichenko, Mariia Shved, Volodymyr Riznyk, Halyna Bilushchak, Olexandr Borisenko, Mikhailo Miroshnychenko, and Yurii Lypko. 2025. "Forecasting Potential Resources of Humic Substances in the Ukrainian Lignite" Resources 14, no. 8: 117. https://doi.org/10.3390/resources14080117
APA StylePyshyev, S., Miroshnichenko, D., Shved, M., Riznyk, V., Bilushchak, H., Borisenko, O., Miroshnychenko, M., & Lypko, Y. (2025). Forecasting Potential Resources of Humic Substances in the Ukrainian Lignite. Resources, 14(8), 117. https://doi.org/10.3390/resources14080117