Effect of joint thermal utilization of carbonaceous waste and rural refuse on ash fusibility

The study aims to determine characteristics of fusibility of ash produced in joint combustion of coal waste and sunflower residue. The chemical composition of ash of initial fuels and their mixtures at different ratios is found. On this basis, the prognostic indicators were calculated to evaluate probability of scale formation on walls of boiler units. For the analysis of ash behavior, the representative temperatures of ash fusion are determined using the standardized methods. The mechanisms of interaction between individual components of ash of carbonaceous and plant raw materials with formation of new mineral phases are described. It is found that addition of sunflower residue in amount of up to 30%w/w to carbonaceous waste lead to a decrease in the fusion temperature of ash. The further increase in the mass fraction of sunflower residue enhances its resistance to thermal influence. The results demonstrate that control of a biomass proportion in mixed fuels allows adjustment of their fusion temperature.

Duka A. A., Pashkevich M. A., Sverchkov I. P. Effect of joint thermal utilization of carbonaceous waste and rural refuse on ash fusibility. MIAB. Mining Inf. Anal. Bull. 2025;(9):67-85. [In Russ]. DOI: 10.25018/0236_1493_2025_9_0_67.

The study was supported by the Ministry of Science and Higher Education of the Russian Federation (FSRW-2024-0005).

A.A. Duka¹, Researcher, e-mail: duka_aa@pers.spmi.ru, ORCID ID: 0009-0009-6656-7660,
M.A. Pashkevich¹, Dr. Sci. (Eng.), Professor, Head of Chair, e-mail: mpash@spmi.ru, ORCID ID: 0000-0001-7020-8219,
I.P. Sverchkov¹, Cand. Sci. (Eng.), Senior Researcher, e-mail: sverchkov_ip@pers.spmi.ru, ORCID ID: 0000-0003-4725-0050,
¹ Empress Catherine II Saint-Petersburg Mining University, 199106, Saint-Petersburg, Russia.

A.A. Duka, e-mail: duka_aa@pers.spmi.ru.

1. Marinina O., Nevskaya M., Jonek-Kowalska I., Wolniak R., Marinin M. Recycling of coal fly ash as an example of an efficient circular economy: A stakeholder approach. Energies. 2021, vol. 14, pp. 3597—3597. DOI: 10.3390/en14123597.

2. Zhang L., Ponomarenko T. Directions for sustainable development of China’s сoal Industry in the post-epidemic era. Sustainability. 2023, vol. 15, no. 8, article 6518. DOI: 10.3390/su15086518.

3. Pashkevich M. A., Patokin D. A., Danilov A. S. Processing the nitrocellulose-containing waste from the chemical industry to obtain mineral soil additives. Ecology and Industry of Russia. 2024, no. 28(6), pp. 10—17. [In Russ]. DOI: 10.18412/1816-0395-2024-6-10-17.

4. Cheng F., Zhang Y., Zhang G., Zhang Z., Wu J., Zhang D. Eliminating environmental impact of coal mining wastes and coal processing by-products by high temperature oxy-fuel CFB combustion for clean power Generation: A review. Fuel. 2024, vol. 373, article 132341. DOI: 10.1016/j. fuel.2024.132341.

5. Lange I. Yu., Lebedeva Y. A., Kotiukov P. V. A study of water permeability of coal ash and slag to assess the possibility of their use as road pavement layers. International Journal of Engineering Research and Technology. 2020, vol. 13, no. 2, pp. 374—378. DOI: 10.37624/IJERT/13.2.2020.374-378.

6. Chukaeva M. A., Matveeva V. A. Complex processing of high-carbon ash and slag waste. Journal of Mining Institute. 2022, vol. 253, pp. 97—104. [In Russ]. DOI: 10.31897/PMI.2022.5.

7. Zhang L., Wang J., Song X., Bai Y., Yao M., Yu G. Influence of biomass ash additive on fusion characteristics of high-silicon-aluminum coal ash. Fuel. 2020, vol. 282, article 118876. DOI: 10.1016/ j.fuel.2020.118876.

8. Huang J., Li Z., Chen B., Cui S., Lu Z., Dai W., Zhao Y., Duan C., Dong L. Rapid detection of coal ash based on machine learning and X-ray fluorescence. Journal of Mining Institute. 2022, vol. 256, pp. 663—676. [In Russ]. DOI: 10.31897/PMI.2022.89.

9. Kiryushina E. V., Zenkov I. V., Hung T. L., Dmitrieva M. L., Yuronen Yu. P., Vokin V. N., Cherepanov E. V., Raevich K. V., Latyntsev A. A., Pavlova P. L., Kuzina L. N., Lunev A. S., Shtresler K. A. Environmental studies of disturbed lands after coal mine closure on sites of the Moscow Region coal basin in the Tula Region. Ugol'. 2024, no. 7, pp. 91—95. [In Russ]. DOI: 10.18796/004157902024-7-91-95.

10. Aleksandrova T., Nikolaeva N., Afanasova A., Chenlong D., Romashev A., Aburova V., Prokhorova E. Increase in Recovery efficiency of iron-containing components from ash and slag material (coal combustion waste) by magnetic separation. Minerals. 2024, vol. 14, no. 2, article 136. DOI: 10.3390/min14020136.

11. Andreenko T. I., Kiseleva S. V., Rafikova J. Yu. Energy potential of agricultural waste in the southern regions of Russia (Volgograd region, Republic of Crimea). Don agrarian science bulletin. 2017, no. 39, pp. 63—72. [In Russ].

12. Kovekhova A. V., Arefieva O. D., Zemnukhova L. A., Samokhina D. A. Inorganic compounds of sunflower stems. Izvestiya Vuzov. Prikladnaya Khimiya i Biotekhnologiya. 2023, vol. 13, no. 2, pp. 220—227. [In Russ]. DOI: 10.21285/2227-2925-2023-13-2-220-227.

13. Zhuikov A., Glushkov D., Pleshko A., Grishina I., Chicherin S. Co-combustion of coal and biomass: Heating surface slagging and flue gases. Fire. 2025, vol. 8, no. 3, article 106. DOI: 10.3390/ fire8030106.

14. Zhou C., Liu G., Wang X., Qi C. Co-combustion of bituminous coal and biomass fuel blends: Thermochemical characterization, potential utilization and environmental advantage. Bioresource Technology. 2016, vol. 218, pp. 418—427. DOI: 10.1016/j.biortech.2016.06.134.

15. Fu B., Liu G., Mian M., Zhou C., Sun M., Wu D., Liu Y. Co-combustion of industrial coal slurry and sewage sludge: Thermochemical and emission behavior of heavy metals. Chemosphere. 2019, vol. 233, pp. 440—451. DOI: 10.1016/j.chemosphere.2019.05.256.

16. Fermoso J., Corbet T., Ferrara F., Pettinau A., Maggio E., Sanna A. Synergistic effects during the co-pyrolysis and co-gasification of high volatile bituminous coal with microalgae. Energy Conversion and Management. 2018, vol. 164, pp. 399—409. DOI: 10.1016/j.enconman.2018.03.02.

17. Zhu H., Liao Q., Hu L., Xie L., Qu B., Gao R. Effect of removal of alkali and alkaline earth metals in cornstalk on slagging/fouling and co-combustion characteristics of cornstalk/coal blends for biomass applications. Renewable Energy. 2023, vol. 207, pp. 275—285. DOI: 10.1016/j.renene.2023.03.022.

18. Niu Y., Tan H., Wang X., Liu Z., Liu H., Liu Y., Xu T. Study on fusion characteristics of biomass ash. Bioresource Technology. 2010, vol. 101, no. 23, pp. 9373—9381. DOI: 10.1016/j.biortech.2010.06.144.

19. Du S., Yang H., Qian K., Wang X., Chen H. Fusion and transformation properties of the inorganic components in biomass ash. Fuel. 2014, vol. 117, pp. 1281—1287. DOI: 10.1016/j.fuel.2013.07.085.

20. Kharko P. A., Danilov A. S. Evaluation of the effectiveness of neutralization and purification of acidic waters from metals with ash when using alternative fuels from municipal waste. Journal of Mining Institute. 2024, pp. 1—10. EDNCGGRHJ. [In Russ].

21. Zhu Y., Tan H., Niu Y., Wang X. Experimental study on ash fusion characteristics and slagging potential using simulated biomass ashes. Journal of the Energy Institute. 2018, vol. 92, no. 6, pp. 1889—1896. DOI: 10.1016/j.joei.2018.11.005.

22. Lachman J., Baláš M., Lisý M., Lisá H., Milčák P., Elbl P. An overview of slagging and fouling indicators and their applicability to biomass fuels. Fuel Processing Technology. 2021, vol. 217, article 106804. DOI: 10.1016/j.fuproc.2021.106804.

23. Petrova T. A., Epishina A. D. Anti-corrosion protection of pipelines at mining and processing enterprises. Obogashchenie Rud. 2023, no. 6, pp. 52—58. [In Russ]. DOI: 10.17580/or.2023.06.09.

24. Qin Y., Feng M., Zhao Z., Vassilev S. V., Feng J., Vassileva C. G., Li W.-Y. Effect of biomass ash addition on coal ash fusion process under CO2 atmosphere. Fuel. 2018, vol. 231, pp. 417—426. DOI: 10.1016/J.FUEL.2018.05.110.

25. Pang C. H., Hewakandamby B., Wu T., Lester E. An automated ash fusion test for characterisation of the behaviour of ashes from biomass and coal at elevated temperatures. Fuel. 2013, vol. 103, pp. 454—466. DOI: 10.1016/j.fuel.2012.06.120.

26. Avgushevich I. V., Sidoruk E. I., Bronovets T. M. Standartnye metody ispytaniya ugley. Klassifikatsii ugley [Standard test methods for coals. Classifications of coals], Moscow, 2019, 576 p.

27. Yao X., Zhou H., Xu K., Xu Q., Li L. Evaluation of the fusion and agglomeration properties of ashes from combustion of biomass, coal and their mixtures and the effects of K2CO3 additives. Fuel. 2019, vol. 255, article 115829. DOI: 10.1016/j.fuel.2019.115829.

28. Ma X., Li F., Ma M., Fang Y. Investigation on blended ash fusibility characteristics of biomass and coal with high silica—alumina. Energy & Fuels. 2017, vol. 31, no. 8, pp. 7941—7951. DOI: 10.1021/acs.energyfuels.7b01070.

29. Chen C., Bi Y., Huang Y., Huang H. Review on slagging evaluation methods of biomass fuel combustion. Journal of Analytical and Applied Pyrolysis. 2021, vol. 155, no. 9, article 105082. DOI: 10.1016/j.jaap.2021.105082.

30. Zhuikov A., Glushkov D., Pleshko A., Grishina I., Chicherin S. Co-combustion of coal and biomass: heating surface slagging and flue gases. Fire. 2025, vol. 8, no. 3, article 106. DOI: 10.3390/ fire8030106.

31. Vassilev S. V., Baxter D., Vassileva C. G. An overview of the behaviour of biomass during combustion: part I. Phase-mineral transformations of organic and inorganic matter, Online. Fuel. 2013, vol. 112, pp. 391—449. DOI: 10.1016/j.fuel.2013.05.043.

32. Vassilev S. V., Baxter D., Vassileva C. G. An overview of the behaviour of biomass during combustion: Part II. Ash fusion and ash formation mechanisms of biomass types. Fuel. 2014, vol. 117, pp. 152—183. DOI: 10.1016/j.fuel.2013.09.024.

33. Deng S., Tan H., Wei B., Wang X., Yang F., Xiong X. Investigation on combustion performance and ash fusion characteristics of Zhundong coal co-combustion with coal gangue. Fuel. 2021, vol. 294, article 120555. DOI: 10.1016/j.fuel.2021.120555.

34. Lv Y., Niu Y., Liang Y., Liu S., Wang D., Hui S. Experiment and kinetics studies on ash fusion characteristics of biomass/coal mixtures during combustion. Energy & Fuels. 2019, vol. 33, no. 10, pp. 10317—10323. DOI: 10.1021/acs.energyfuels.9b02563.

35. Vu D. H., Bui H. B., Bui X. N., An-Nguyen D., Le Q. T., Do N. H., Nguyen H. A novel approach in adsorption of heavy metal ions from aqueous solution using synthesized MCM-41 from coal bottom ash. International Journal of Environmental Analytical Chemistry. 2020, vol. 100, no. 11, pp. 1226— 1244. DOI: 10.1080/03067319.2019.1651300.

36. Yiming Z., Houzhang T., Yanqing N., Xuebin W. Experimental study on ash fusion characteristics and slagging potential using simulated biomass ashes. Journal of the Energy Institute. 2018, vol. 92, no. 6, pp. 1889—1896. DOI: 10.1016/j.joei.2018.11.005.

37. Zhai M., Li X., Yang Di., Ma Zh., Dong P. Ash fusion characteristics of biomass pellets during combustion. Journal of Cleaner Production. 2022, vol. 336, article 130361. DOI: 10.1016/j. jclepro.2022.130361.