📄 Sciences Methods and Technologies
International Journal (SciMeTech)

Volume 2 · Issue 2 · 2026
ISSN: 3085-5284
Eco-Friendly Sustainable Drying Techniques for Sludge from Drinking Water Treatment Plants
Daoud EL-ALOUANY, Fatiha BERROUGG, Laben BOUKHATTEM
Pages 130–132 · 1. Laboratory of Sciences Mechanic and Energy, Faculty of Sciences Semlalia, Cadi Ayyad University, Marrakech 40000, Morocco · 2. Center of Sciences and Research on Water and Energy, Cadi Ayyad University, Marrakech 40000, Morocco · 3. National School of Applied Sciences, Cadi Ayyad University, Marrakech 40000, Morocco
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Abstract
The management of sludge generated from Drinking Water Treatment Plants (DWTPs) represents a growing environmental and operational challenge due to its high moisture content and disposal constraints. Conventional thermal drying techniques, although effective, are energy-intensive and contribute significantly to greenhouse gas emissions. This study presents a comparative review of eco-friendly and sustainable drying technologies applicable to DWTP sludge. A systematic analysis of published literature was conducted to evaluate solar drying, greenhouse-assisted drying, low-temperature thermal drying, waste heat-assisted drying, and bio-drying processes. The comparison was based on drying efficiency, energy consumption, carbon emission impact, economic feasibility, and scalability potential. The findings indicate that solar and greenhouse drying systems offer minimal direct energy consumption but are climate-dependent. Waste heat-assisted drying provides a balanced compromise between efficiency and sustainability by reducing primary energy demand by up to 60%. Conventional thermal drying ensures rapid moisture removal but remains the most energy-intensive option. The review highlights the need for DWTP-specific optimization strategies and supports the development of hybrid systems integrating renewable or recovered energy sources to enhance sustainability and align with circular economy principles.
Keywords: Drying, Drinking water treatment sludge, Solar drying, Waste heat recovery, Circular economy

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SciMeTech · Volume 2, Issue 2 · 2026 · ISSN 3085-5284