AccScience Publishing / AJWEP / Online First / DOI: 10.36922/AJWEP025130093
Submit to AJWEP
Cite this article
15
Download
78
Views
Journal Browser
Volume | Year
Issue
Search
Forthcoming Issue
Current Issue
View All
News and Announcements
View All
REVIEW ARTICLE

A critical review of recent dewatering technologies: Performance and applications

Hari Bahadur Darlami1 ,  Ajay Kumar Jha1* ,  Kshitiz Ghimire1
Show Less
1 Department of Aerospace and Mechanical Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University, Nepal
AJWEP, 025130093 https://doi.org/10.36922/AJWEP025130093
Received: 27 March 2025 | Revised: 17 June 2025 | Accepted: 1 July 2025 | Published online: 6 August 2025
© 2025 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Download PDF
Cite
XML
Abstract

Biogas plants play a major role in Nepal’s renewable energy efforts. However, managing the by-product remains challenging due to its high water content. The high water content increases the difficulty in transporting, storing, or reusing the material, especially in rural and farming areas. Dewatering provides a practical solution by removing moisture, thereby transforming the slurry into a drier, more manageable material. This review compares several dewatering technologies used in agriculture, industry, and wastewater treatment, with a focus on how they can help manage biogas slurry in developing countries such as Nepal. Various machines, such as screw presses, belt presses, and centrifuges, as well as novel method including thermally assisted mechanical dewatering (TAMD), are included in this review. These technologies were compared based on key factors, including moisture removal rate, energy consumption, nutrient saving, and operational parameters. Results show that TAMD gives the best moisture removal, whereas screw presses use less energy and keep useful nutrients in the digestate. Low-cost and fuel-free machines also show potential for small-scale use in rural areas. Despite these options, the data, infrastructure, and support to apply these technologies widely are still insufficient in Nepal. This paper highlights the need for improved local research, enhanced policies, and increased investment to enlarge the scale of these systems. Doing so could help Nepal maximize the value of its biogas plants, providing cleaner energy and enhancing agricultural productivity.

Keywords
Dewatering
Organic fertilizers
Biodigestate
Sun drying
Total solid
Thermally assisted mechanical dewatering
Funding
The authors would like to thank the University Grant Commission, Bhaktapur, Nepal, for granting us with UGC Faculty Research Grant (Award No. FRG-78/79-Engg-01).
Conflict of interest
The authors declare they have no competing interests.
References
  1. Water and Energy Commission Secretariat. Energy Sector Synopsis Report. Kathmandu: Water and Energy Commission Secretariat; 2024.

 

  1. Alternative Energy Promotion Centre. Progress at a Glance: Year in Review FY 2080/81 (2023/24). Kathmandu: Alternative Energy Promotion Centre; 2024.

 

  1. Woli L. Biogas plants and its impact on rural life in Nepalese communities. Shanti J. 2022;1:197-216. doi: 10.3126/shantij.v1i1.47817

 

  1. Raut P, Koirala S. Study of Slurry Management in Waste-to-Energy Large Scale Biogas Plants in Nepal. Kathmandu: Alternative Energy Promotion Center; 2021.

 

  1. Rao B, Wang G, Xu P. Recent advances in sludge dewatering and drying technology. Drying Technol. 2022;40(15):3049-3063. doi: 10.1080/07373937.2022.2043355

 

  1. Exabytes. Fabriflex. Available from: https://www. fabriflex.com.my/articles/dewatering-bags-sludge-management [Last accessed on 2024 Apr 15].

 

  1. Kumar A, Verma LM, Sharma S, Singh N. Overview on agricultural potentials of biogas slurry (BGS): Applications, challenges, and solutions. Biomass Convers Biorefin. 2023;13:13729-13769. doi: 10.1007/s13399-021-02215-0

 

  1. Jha AK, Darlami HB, Gautam R, Pun K. Production of clean energy from duckweed. Int J Eng Technol. 2024;2(1):80-95. doi: 10.3126/injet.v2i1.72523

 

  1. Shere DP, Agrawal DR. Extrusion Technology: Transforming Food Processing. New Delhi: BP International; 2024.

 

  1. Roos, CJ. Biomass Drying and Dewatering for Clean Heat and Power. Washington, DC: U.S. Department of Energy and National Renewable Energy Laboratory. 2008. Available from: https://www.nrel.gov/docs/ fy00osti/28097.pdf [Last accessed on 2025 Apr 15].

 

  1. Chaedir BA, Kurnia JC, Sasmito AP, Mujumdar AS. Advances in dewatering and drying in mineral processing. Drying Technol. 2021;39(11):1667-1684. doi: 10.1080/07373937.2021.1907754

 

  1. Zhang X, Ye P, Wu Y. Enhanced technology for sewage sludge advanced dewatering from an engineering practice perspective: A review. J Environ Manage. 2022;321:115938. doi: 10.1016/j.jenvman.2022.115938

 

  1. Pan JR, Huang C, Cherng M, Li KC, Lin CF. Correlation between dewatering index and dewatering performance of three mechanical dewatering devices. Adv Environ Res. 2003;7:599-602. doi: 10.1016/S1093-0191(02)00052-7

 

  1. Zhou X, Jiang G, Wang Q, Yuan Z. A review on sludge conditioning by sludge pre-treatment with a focus on advanced oxidation. Royal Soc Chem Adv. 2014;4:50644-50652. doi: 10.1039/C4RA07235A

 

  1. Roos CJ. Biomass Drying and Dewatering for Clean Heat and Power. Washington: Springer; 2008.

 

  1. Al Seadi T, Drosg B, Fuchs W, Rutz D, Janssen R. Biogas digestate quality and utilization. In: The Biogas Handbook. Netherlands: Elsevier; 2013.

 

  1. Rojas M, Manrique R, Hornung U, et al. Advances and challenges on hydrothermal processes for biomass conversion: Feedstock flexibility, products, and modeling approaches. Biomass Bioenergy. 2025;194:107621. doi: 10.1016/j.biombioe.2025.107621

 

  1. Yadav S, Jha AK, Darlami HB. Design and improvement of dewatering system implemented for biogas slurry. Int J Multidiscip Res. 2023;5(6):1-27. doi: 10.36948/ijfmr.2023.v05i06.9184

 

  1. Ford M, Fleming R. Mechanical Solid-Liquid Separation of Livestock Manure Literature Review. Ontario: Ridgetown College; 2002.

 

  1. Mohanty MK. Screen bowl centrifuge dewatering process: A parameteric study. Phys Sep Sci Eng. 2007;1(2):70376. doi: 10.1155/2007/70376

 

  1. Powers JP, Corwin AB, Schmall PC, Kaeck WE. Construction Dewatering and Groundwater Control: New Methods and Applications. New Jersey: John Wiley and Sons, Inc.; 2007.

 

  1. Emerging Technologies for Biosolids Management. EPA.Gov; 2006. Available from: https://www.epa.gov/ biosolids/emerging-technologies-biosolids-management [Last accessed on 2025 Apr 15].

 

  1. Riedel DJ. An Investigation into the Mechanisms of Sludge Reduction Technologies, MSc Thesis, Department of Civil and Environmental Engineering. Blacksburg, USA: Virginia Polytechnic Institute and State University; 2009.

 

  1. More M, Agrawal C, Sharma D. Development of screw press-dewatering unit for biogas slurry. In: Chokkadi S, Bandyopadhyay R, editors. Smart Sensors Measurement and Instrumentation. Lecture Notes in Electrical Engineering. Singapore: Springer; 2023.

 

  1. Guev V, Zazykina L, Sysoeva I, Lukashenko V. Advantages and disadvantages of mechanical manure dewatering. E3S Web Conf. 2021;285:04004. doi: 10.1051/e3sconf/202128504004

 

  1. Śniatała B, Al-Hazmi HE, Sobotka D, Zhai J, Makinia J. Advancing sustainable wastewater management: A comprehensive review of nutrient recovery products and their applications. Sci Total Environ. 2024;937:173446. doi: 10.1016/j.scitotenv.2024.173446

 

  1. Kataria Mahendra B, George PM, Mehta H, Jivani RG. Experiments for Deisgning a Screen for a Screw Press for Dewatering of Cattle Dung Slurry. Chennai: National Conference on Recent Trends in Engineering and Technology; 2011.

 

  1. Mahmoud A, Olivier J, Vaxelaire J, Hoadley AFA. Electro-dewatering of wastewater sludge: Influence of the operating conditions and their interactions effects. Water Res. 2011;45:2795-2810. doi: 10.1016/j.watres.2011.02.029

 

  1. Drosg B, Baxter D. Nutrient Recovery by Biogas Digestate Processing. UK: IEA Bioenergy; 2015.

 

  1. Mahmoud A, Fernandez A, Arlabosse P, Cammarata G, editor. Analysis of Electrical Phenomena Occurring in Thermally Assisted Mechanical Dewatering Processes (TAMD)-a Preliminary Study, Modelling and Simulation. Croatia: InTech; 2008.

 

  1. Mahmoud A, Arlabosse P, Fernandez A. Application of a thermally assisted mechanical dewatering process to biomass. Biomass Bioenergy. 2011;35(1):288-297. doi: 10.1016/j.biombioe.2010.08.037

 

  1. Chen W. Optimization of sludge dewatering through pretreatment, equipment selection, and testing. Drying Technol. 2013;31:193-201. doi: 10.1080/07373937.2012.723658

 

  1. Wakeman RJ. Separation technologies for sludge dewatering. J Hazard Mater. 2007;144:614-619. doi: 10.1016/j.jhazmat.2007.01.084

 

  1. Bhojwani S, Topolski K, Mukherjee R, Sengupta D, El-Halwagi MM. Technology review and data analysis for cost assessment of water treatment systems. Sci Total Environ. 2019;651:2749-2761. doi: 10.1016/j.scitotenv.2018.09.363

 

  1. Liu Z, Luo F, He L, Wang S, Wu Y, Chen Z. Physical conditioning methods for sludge deep dewatering: A critical review. J Environ Manage. 2024;360:121207. doi: 10.1016/j.jenvman.2024.121207

 

  1. Verheijen LAHM, Wiersema D, Pol LWH. Handling of by-Products and Treatment of Waste. Management of Waste from Animal Product Processing. Amsterdam: J. De Wit International Agriculture Centre; 1996.

 

  1. Chen G, Yue PL, Mujumdar AS. Sludge dewatering and drying. Drying Technol. 2006;20:883-916. doi: 10.1081/DRT-120003768

 

  1. Molinos-Senante M, Maziotis A. Evaluation of energy efficiency of wastewater treatment plants: The influence of the technology and aging factors. Appl Energy. 2022;310:118535. doi: 10.1016/j.apenergy.2022.118535

 

  1. Asmarketing. Engineers for Life. Available from: https://sludgedryer.in/belt-filter-press-vs-screw-press-dewatering-the-ultimate-guide-for-efficient-sludge-management [Last accessed on 2025 Apr 09].

 

  1. Lee JY, Chen PY. Optimization of heat recovery networks for energy savings in industrial processes. Processes. 2023;11(2):321. doi: 10.3390/pr11020321

 

  1. Malik A, Sohani E, Shahreza MS, Aliyu AM. Retrofitting of a full-scale dewatering operation for industrial polymer effluent sludge. Advances in new methods of wastewater treatment and management). Processes. 2024;12(4):703. doi: 10.3390/pr12040703

 

  1. Buckley R, Spagnuolo EK. Techno-economic assessment of underground mine dewatering systems. In: Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining. Perth: Australian Centre for Geomechanics; 2024.

 

  1. Novak JT. Dewatering of sewage sludge. Drying Technol. 2006;24(10):1257-1262. doi: 10.1080/07373930600840419

 

  1. Meyer T, Amin P, Allen DG, Tran H. Dewatering of pulp and paper mill biosludge and primary sludge. J Environ Chem Eng. 2018;6(5):6317-6321. doi: 10.1016/j.jece.2018.09.037

 

  1. Jha AK, Jojiju S, Darlami H, Basnet B. Performance evaluation of dewatering systems for bio-digestate for developing countries. Energy Storage Conver. 2024;2(3):1431. doi: 10.59400/esc.v2i3.1431

 

  1. Olusegun HD, Ajiboye TK. The design, construction and testing of a vertical squeeze cassava pulp dewatering machine. Int J Eng Appl Sci (IJEAS). 2010;2(1):27-43.

 

  1. Mudryk K, Jaroslaw Fraczek MJ, Wrobel M, Dziedzic K. Analysis of mechanical dewatering of digestate. Agric Eng. 2016;20(4):157-166. doi: 10.1515/agriceng-2016-0073

 

  1. Marcel EO, Nduka NB, Abam FI. Multiobjective optimization of integrated milling-sieving-dewatering machine for grain slurry starch production. Futo J Ser (FUTOJNLS). 2021;7(2):82-91.

 

  1. Afeni TB, Adebanjo TL, Idowu KA, Akindutire T. Design and fabrication of fueless dewatering machine for small and medium scale miners. J Inventive Eng Technol (JIET). 2021;1(2):1-11.

 

  1. Bergins C, Hulston J, Strauss K, Chaffee AL. Mechanical/ thermal dewatering of lignite. Part 3: Physical properties and pore structure of MTE product coals. Fuel. 2007;86(1-2):3-16. doi: 10.1016/j.fuel.2006.06.019

 

  1. Lin L, Wang Y, Liu X, Zhang X. Water-absorption-trough dewatering machine for estimation of organic carbon in moist soil. Environ Pollut. 2021;284:117445. doi: 10.1016/j.envpol.2021.117445
Share
Back to top
Asian Journal of Water, Environment and Pollution, Electronic ISSN: 1875-8568 Print ISSN: 0972-9860, Published by AccScience Publishing
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here
Accept