Critical review on on-site sanitation technologies: Typologies, treatment and transition towards circular economy

• Published in: Bioresource technology 2025-02, Vol.418, p.131954, Article 131954
• Main Authors: Patwa, Aakash, Kumar, Amit, Vijay, Ritesh
• Format: Article
• Language: English
• Subjects: Challenges; Characteristics; Faecal sludge; Resource Recovery; Sanitation; Septage
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2024.131954

[Display omitted] •On-site sanitation from source to solution in diverse global contexts.•On-site sanitation requires cost-effective nature-based treatment with less footprint.•Need for research and development in on-site treatment of faecal sludge.•Emphasis on resource recovery and circular economy for sustainable sanitation. Around 4.2 billion people globally depend on on-site sanitation systems, with 43% relying on basic or unsafe facilities with key challenges of containment, emptying, transport, treatment and resource recovery from faecal sludge. This review paper critically examines faecal sludge characteristics and treatment technologies in terms of urine diversion capability, land requirements and capital as well as operational expenditure based on Indian and international practices. Apart from these, the review also provides reuse-recycle of processed manure, treated effluent and bio-energy from faecal sludge to create environmental and economic benefits. The review also highlights future research on the development of nature-based solutions for solid–liquid separation and treatment, low footprints and on-site treatment for fostering a circular economy. Ultimately this review emphasizes the importance of advancing faecal sludge management to address global sanitation challenges and to create sustainable solutions for environmental protection.