Faecal sludge (Septage) is the slurry that contains both solid and liquid waste that accumulates in onsite sanitation systems (OSS) e.g. septic tanks. It is raw or partially digested slurry that results from the collection, storage or treatment of combinations of excreta and blackwater, with or without greywater. This has three main components – scum, effluent and sludge. It has an offensive odour, appearance and contains significant levels of grease, grit, hair, debris and pathogenic micro organisms. In the current scenario, the construction and management of OSS are left largely to ineffective local practices and there is lack of holistic septage management practices.
|Faecal sludge (septage) management involves collection, treatment and proper disposal/ reuse. Efficient faecal sludge (septage) management include safe disposal of the treated septage.|
It is safe removal of septage from on-site sanitation systems. In urban areas different situations prevail that facilitates or restricts collection of septage from septic tanks. There are variety of OSS in urban/ small towns and cities wherein the rate of septage generation will vary and thus influence the collection.
It is taking septage from source to treatment facility. Most commonly in urban areas of India de-sludging trucks, mounted tractors; vacuum trucks are used to collect the septage. Th e size and design varies across India for transport vehicles and are mostly indigenously assembled. For inaccessible areas small sized vaccutug, are more convenient for de-sludging septage.
Septage can be treated in a variety of ways that is best suitable for the region. There are varieties of options that can be appropriately selected considering factors like cost and reuse possibilities. The quality and quantity of septage desludged from on-site systems also affects the selection of treatment option. Land application, co-treatment at STP, natural treatment options and dewatering and co-composting with solid waste are some of common and easily adaptable treatment options.
|Disposal / reuse
The humus produced after composting can be used as a soil conditioner. Septage can also be used as an energy resource. There are some international and national examples where experiments have been conducted to generate energy from Septage.
|Waste to Energy Plant, Nashik, Maharashtra|
|Green Bio-compost and Animal Farming for Faecal sludge treatment|
|FSTP at Khulna, Bangladesh|
|FSTP at Jhenaidah, Bangladesh|
|FSTP at Faridpur, Bangladesh|
|FSTP at Leh, India|
|Centralized Sludge Treatment Facility (CSTF), Sungai Udang, Malaysia|
|Geobag for fecal sludge drying – Malacca, Malaysia|
|Regional Sewage Treatment Plant (Co-treatment of fecal sludge) at Kuala Sawah, Malaysia|
|Faecal Sludge Treatment at Devanahalli Bengaluru|