Kinetics of the Drying Process of Composite Biopellets on a Convective Drying Bench

image_print
DOI https://doi.org/10.15407/pmach2025.03.023
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher Anatolii Pidhornyi Institute of Power Machines and Systems
of National Academy of Science of Ukraine
ISSN  2709-2984 (Print), 2709-2992 (Online)
Issue Vol. 28, no. 3, 2025 (September)
Pages 23-33
Cited by J. of Mech. Eng., 2025, vol. 28, no. 3, pp. 23-33

 

Authors

Zhanna O. Petrova, Institute of Technical Thermophysics of NAS of Ukraine (2a, Maria Kapnist str., Kyiv, 03057, Ukraine), e-mail: bergelzhanna@ukr.net, ORCID: 0000-0001-7385-8495

Vadym M. Paziuk, Institute of Technical Thermophysics of NAS of Ukraine (2a, Maria Kapnist str., Kyiv, 03057, Ukraine), e-mail: vadim_pazuk@ukr.net, ORCID: 0000-0002-4955-1941

Yuliia P. Novikova, Institute of Technical Thermophysics of NAS of Ukraine (2a, Maria Kapnist str., Kyiv, 03057, Ukraine), e-mail: yuliianovikova3@gmail.com, ORCID: 0000-0002-6705-1000

Anton I. Petrov, Institute of Technical Thermophysics of NAS of Ukraine (2a, Maria Kapnist str., Kyiv, 03057, Ukraine), e-mail: monoton10@gmail.com, ORCID: 0000-0003-4851-3115

 

Abstract

In Ukraine, there is a problem of overflowing sediment maps, to which activated sludge, which eventually turns into sludge deposits, is constantly added. The accumulated sludge deposits are outdated, have lost most of their nutrients, became too mineralized and are practically unsuitable for direct biofuel production. The elimination of accumulated sediments is necessary for the efficient and uninterrupted operation of treatment plants, as well as for land reclamation. However, due to the energy crisis around the world, it is possible to use them with the creation of fuels based on obsolete sludge, peat and biomass to solve this problem. Therefore, it is important to develop a technology for processing obsolete sludge into fuel pellets that can be used as fuel for, as an example, mini-CHPPs that simultaneously produce heat and electricity. Since obsolete sludge deposits have a low content of organic matter, it is proposed to create composite pellets for their better utilization, followed by their drying and combustion, in which the resulting ash will be used to make building materials. Therefore, the aim of the study was to investigate the drying processes of composite pellets on a convective plant and generalize them with a theoretical calculation. The drying processes of composite pellets based on obsolete sludge deposits, peat and biomass and identifies effective drying modes are studied in the paper. As a result, the influence of the coolant temperature on the drying time of the sludge-peat composition was determined, which shows that an increase in temperature reduces the drying time of the pellets by 1.4 times. Comparison of the drying kinetics of two- and three-component pellets at 80 °C and 120 °C indicates that the drying time of three-component pellets is by 1.1 to 1.4 times shorter than that of two-component pellets. Increasing the temperature of the coolant reduces the drying time of three-component pellets by about 1.5 times. Theoretical studies with the construction of generalized drying curves for composite pellets calculated by the method of V. V. Krasnikov showed a coincidence with experimental data. The relative and kinetic drying coefficients were calculated from the generalized drying curves and the drying speed, and the formulas for the drying time of two- and three-component pellets were obtained.

 

Keywords: sludge deposits, peat, biomass, granulation, briquettes, drying.

 

Full text: Download in PDF

 

References

  1. (2007). Mulovyi maidanchyk [Sludge pad]: Patent 27951 Ukraine: MPK (2006) C02F 11/00, u200705576, announced 05/21/2007, published 11/26/2007 (in Ukrainian).
  2. Sniezhkin, Yu. F., Petrova, Zh. O., Paziuk, V. M., & Novykova, Yu. P. (2021). Stan tekhnolohii ochyshchennia stichnykh vod v Ukraini ta sviti [State of wastewater treatment technologies in ukraine and the world]. Teplofizyka ta teploenerhetyka – Thermophysics and Thermal Power Engineering, vol. 43, no. 1, pp. 5–12. https://doi.org/10.31472/ttpe.1.2021.1.
  3. Kamyab Moghadas, B., Fallah Fard, H., & Ghasemi, M. (2025). Analyzing and reusing industrial wastewater sludge in cement production: Environmental and economic implications. Results in Chemistry, vol. 16, article 102299. https://doi.org/10.1016/j.rechem.2025.102299.
  4. Salazar-Batres, K. J. & Moreno-Andrade, I. (2025). Review of the effects of trace metal concentrations on the anaerobic digestion of organic solid waste. BioEnergy Research, vol. 18, article 24. https://doi.org/10.1007/s12155-025-10826-y.
  5. Zandvoort, M. H., van Hullebusch, E. D., Gieteling, J., & Lens, P. N. L. (2006). Granular sludge in full-scale anaerobic bioreactors: trace element content and deficiencies. Enzyme and Microbial Technology, vol. 39, iss. 2, pp. 337–346. https://doi.org/10.1016/j.enzmictec.2006.03.034.
  6. Zhang, Y., Feng, Y., Yu, Q., Xu, Z., & Quan, X. (2014). Enhanced high-solids anaerobic digestion of waste activated sludge by the addition of scrap iron. Bioresours Technology, vol. 159, pp. 297–304. https://doi.org/10.1016/j.biortech.2014.02.114.
  7. Agani, I. C., Suanon, F., Biaou, D., Yovo, F., Tomètin, L. A. S., Mama, D., & Azandegbe, E. C. (2016). Biogas recovery from sewage sludge during anaerobic digestion process: effect of iron powder on methane yield. International Research Journal of Environment Science, vol. 5 (1), pp. 7–12.
  8. Gran, S, Motiee, H, Mehrdadi, N, & Tizghadam, M. (2022). Impact of metal oxide nanoparticles (NiO, CoO and Fe3O4) on the anaerobic digestion of sewage sludge. Waste and Biomass Valorization, vol. 13, pp. 4549–4563. https://doi.org/10.1007/s12649-022-01816-8.
  9. Linville, J. L., Shen, Y., Schoene, R. P., Nguyen, M., Urgun-Demirtas, M., & Snyder, S. W. (2016). Impact of trace element additives on anaerobic digestion of sewage sludge with in-situ carbon dioxide sequestration. Process Biochemistry, vol. 51, iss. 9, pp. 1283–1289. https://doi.org/10.1016/j.procbio.2016.06.003.
  10. An, J., Yun, S., Wang, W., Wang, K., Ke, T., Liu, J., Liu, L., Gao, Y., & Zhang, X. (2023). Enhanced methane production in anaerobic co-digestion systems with modified black phosphorus. Bioresource Technology, vol. 368, article 128311. https://doi.org/10.1016/j.biortech.2022.128311.
  11. Liu, L., Yun, S., Ke, T., Wang, K., An, J., & Liu, J. (2023). Dual utilization of aloe peel: aloe peel-derived carbon quantum dots enhanced anaerobic co-digestion of aloe peel. Waste Management, vol. 159, pp. 163–173. https://doi.org/10.1016/j.wasman.2023.01.036.
  12. Núñez, D., Oulego, P., Collado, S., Riera, F. A., & Díaz, M. (2022). Separation and purification techniques for the recovery of added-value biocompounds from waste activated sludge. A review. Resources, Conservation and Recycling, vol. 182, article 106327. https://doi.org/10.1016/j.resconrec.2022.106327.
  13. Geissdoerfer, M., Savaget, P., Bocken, N. M. P., & Hultink, E. J. (2017). The circular economy – A new sustainability paradigm? Journal of Cleaner Production, vol. 143, pp. 757–768. https://doi.org/10.1016/j.jclepro.2016.12.048.
  14. Bharathiraja, B., Yogendran, D., Ranjith Kumar, R., Chakravarthy, M., & Palani, S. (2014). Biofuels from sewage sludge – A review. International Journal of ChemTech Research, vol. 6, no. 9, pp. 4417–4427.
  15. Zhao, P., Shen, Y., Ge, S., & Yoshikawa, K. (2014). Energy recycling from sewage sludge by producing solid biofuel with hydrothermal carbonization. Energy Conversion and Management, vol. 78, pp. 815–821. https://doi.org/10.1016/j.enconman.2013.11.026.
  16. Raheem, A., Sikarwar, V. S., He, J., Dastyar, W., Dionysiou, D. D., Wang, W., & Zhao, M. (2018). Opportunities and challenges in sustainable treatment and resource reuse of sewage sludge: A review. Chemical Engineering Journal, vol. 337, pp. 616–641. https://doi.org/10.1016/j.cej.2017.12.149.
  17. García, M., Urrea, J. L., Collado, S., Oulego, P., & Díaz, M. (2017). Protein recovery from solubilized sludge by hydrothermal treatments. Waste Management, vol. 67, pp. 278–287. https://doi.org/10.1016/j.wasman.2017.05.051.
  18. Li, H., Li, Y., & Li, C. (2013). Characterization of humic acids and fulvic acids derived from sewage sludge. Asian Journal of Chemistry, vol. 25, no. 18, pp. 10087–10091. https://doi.org/10.14233/ajchem.2013.15162.
  19. Suárez-Iglesias, O., Urrea, J. L., Oulego, P., Collado, S., & Díaz, M. (2017). Valuable compounds from sewage sludge by thermal hydrolysis and wet oxidation. A review. Science of the Total Environment, vol. 584–585, pp. 921–934. https://doi.org/10.1016/j.scitotenv.2017.01.140.
  20. Karn, S. K. & Kumar, A. (2019). Protease, lipase and amylase extraction and optimization from activated sludge of pulp and paper industry. Indian Journal of Experimental Biology, vol. 57, pp. 201–205.
  21. Nabarlatz, D., Stüber, F., Font, J., Fortuny, A., Fabregat, A., & Bengoa, C. (2011). Activated sludge characterization: Extraction and identification of hydrolytic enzymes. Water Production and Wastewater Treatment. Nova Science Publishers, Inc., pp. 11–26.
  22. Nabarlatz, D., Vondrysova, J., Jenicek, P., Stüber, F., Font, J., Fortuny, A., Fabregat, A., & Bengoa, C. (2010). Hydrolytic enzymes in activated sludge: Extraction of protease and lipase by stirring and ultrasonication. Ultrasonics sonochemistry, vol. 17, iss. 5, pp. 923–931. https://doi.org/10.1016/j.ultsonch.2010.02.006.
  23. Ni, H., Fan, X. M., Guo, H. N., Liang, J. H., Li, Q. R., Yang, L., Li, H., & Li, H. H. (2017). Comprehensive utilization of activated sludge for the preparation of hydrolytic enzymes, polyhydroxyalkanoates, and water-retaining organic fertilizer. Preparative Biochemistry and Biotechnology, vol. 47, iss. 6, pp. 611–618. https://doi.org/10.1080/10826068.2017.1286599.
  24. Chen, J. (2017). From waste to treasure: turning activated sludge into bioplastic poly-3-hydroxybutyrate. Chinese Journal of Biotechnology, vol. 33, iss. 12, pp. 1934–1944. https://doi.org/10.13345/j.cjb.170391.
  25. Pittmann, T. U. & Steinmetz, H. (2014). Polyhydroxyalkanoate production as a side stream process on a municipal waste water treatment plant. Bioresource Technology, vol. 167, pp. 297–302. https://doi.org/10.1016/j.biortech.2014.06.037.
  26. Jimenez, J., Vedrenne, F., Denis, C., Mottet, A., Déléris, S., Steyer, J. P., & Rivero, J. A. C. (2013). A statistical comparison of protein and carbohydrate characterisation methodology applied on sewage sludge samples. Water Research, vol. 47, iss. 5, pp. 1751–1762. https://doi.org/10.1016/j.watres.2012.11.052.
  27. Wei, L., Wang, K., Kong, X., Liu, G., Cui, S., Zhao, Q., & Cui, F. (2016). Application of ultra-sonication, acid precipitation and membrane filtration for co-recovery of protein and humic acid from sewage sludge. Frontiers of Environmental Science & Engineering, vol. 10, pp. 327–335. https://doi.org/10.1007/s11783-014-0763-9.
  28. Li, H., Li, Y., Jin, Y., Zou, S., & Li, C. (2014). Recovery of sludge humic acids with alkaline pretreatment and its impact on subsequent anaerobic digestion. Journal of Chemical Technology and Biotechnology, vol. 89, iss. 5, pp. 707–713. https://doi.org/10.1002/jctb.4173.
  29. Dong, Y., Zhu, F. F., Zhang, R. Y., Zhang, D. R., Wang, P., & Chen, B. L. (2019). Preliminary study on extraction and purification of ceramide in sewage sludge. China Environmental Science, vol. 39, iss. 5, pp. 2063–2070.
  30. Olkiewicz, M., Caporgno, M. P., Fortuny, A., Stüber, F., Fabregat, A., Font, J., & Bengoa, C. (2014). Direct liquid–liquid extraction of lipid from municipal sewage sludge for biodiesel production. Fuel Processing Technology, vol. 128, pp. 331–338. https://doi.org/10.1016/j.fuproc.2014.07.041.
  31. Revellame, E. D., Hernandez, R., French, W., Holmes, W. E., Benson, T. J., Pham, P. J., Forks, A., & Callahan II, R. (2012). Lipid storage compounds in raw activated sludge microorganisms for biofuels and oleochemicals production. RSC Advances, vol. 2, iss. 5, pp. 2015–2031. https://doi.org/10.1039/C2RA01078J.
  32. Petrova, Zh. O., Novikova, Yu. P. (2021). Pidhotovka syrovyny, stvorennia kompozytsii ta hranuloutvorennia z zastarilykh mulovykh vidkladen, torfu ta biomasy [Preparation of raw materials, creation of compositions and granulation from obsolete sludge, peat and biomass]. Keramika: nauka i zhyttia – Ceramics: Science and Life, no. 1, pp. 14–18 (in Ukrainian). https://doi.org/10.26909/csl.1.2021.2.
  33. Petrova, Zh. A. & Slobodyanyuk, E .S. (2019). Energy-efficient modes of drying of colloidal capillary-porous materials. Journal of Engineering Physics and Thermophysics, vol. 92, iss. 5, pp. 1231–1238. https://doi.org/10.1007/s10891-019-02038-x.
  34. Petrova, Zh. O. & Sniezhkin, Yu. F. (2018). Enerhoefektyvni teplotekhnolohii pererobky funktsionalnoi syrovyny [Energy-efficient heat technologies for processing functional raw materials]. Kyiv: Naukova dumka, 192 p. (in Ukrainian).
  35. Sniezhkin, Yu  F., Paziuk, V. M., Petrova, Zh. O., & Chalaiev, D. M. (2012). Teplonasosna zernosusharka dlia nasinnievoho zerna [Heat pump grain dryer for seed grain]. Kyiv: LLC “Polihraf-Servis”, 154 p. (in Ukrainian).
  36. Tkachenko, S. Y. & Spivak, O. Yu. (2007). Sushylni protsesy ta ustanovky [Drying processes and installations]: A textbook. Vinnytsia: Vinnytsia National Technical University, 76 p. (in Ukrainian).
  37. Pohozhykh, M. I., Potapov, V. O., Pak, A. O., & Zherebkin, M. V. (2016). Enerhoefektyvni tekhnolohii ta tekhnika sushinnia kharchovoi syrovyny [Energy-efficient technologies and techniques for drying food raw materials]: A textbook. Kharkiv: Kharkiv State University of Food Technologies, 234 p. (in Ukrainian).

 

Received 14 May 2025

Accepted 31 May 2025

Published 30 September 2025