Faecal Sludge and Septage Treatment with Thermal Processes at Narsapur

Scale of service

15 cu.m. per day

Area of installation (Sq. Ft.)

12,500 sqft




Biochar*, Treated Water, Thermal Energy

Year of Installation


Capital investment (INR)

1.5 Cr excl. GST

No. of Users


Treatment time

One day. Solids treatment – Typically 12 hours. Liquid treatment – Typically 3 days HRT





Location of the technology:
Google Maps Location - 16.427238 ; 81.700406. The site is on the eastern part of the city near Godavari river. 

Need for technology

Over 70% of India’s towns and cities have no access to sewers or treatment options to manage their septic tank and pit waste. This waste is desludged and disposed in water bodies, drains and fields. The need for septage treatment is to improve the quality of life of the people in these 3000+ non-sewered towns and cities across India and of the truck operators and workers engaged in the sanitation sector. 

System description

The system follows six stages and treats solids and liquids in the septage:
Screening and Storage – A receiving station with screening unit, grit chamber and one day septage storage
Solid-Liquid Separation in the septage – Dewatering unit with polymer dosing, mixing  followed by thickening and dewatering
Removal of Pathogens in the Liquid Filtrate – Pasteurization at 85 C
Treatment of the liquid to meet PCB norms – Phytorid with tertiary treatment facility (PSF+ACF+UV)
Moisture removal from the solids – Mechanical Drying
Treatment of solids for pathogen kill and useful output - Pyrolysis

Operation and maintenance:

Electricity Consumed ( In units)

8 to 12 units per hour for a 10-hour operating day

Maintenance of the installation

Periodic cleaning of the screening unit and grit chamber, Backwash in the pasteurization system and tertiary treatment facility, Cleaning of the heat exchangers, General upkeep, maintenance and tuning.

O&M cost (INR)

 About INR 2.5 lakhs per month in this plant. But typically, INR 1.5 lakhs

Technology provider perspective:

The Thermal FSTP at Narsapur treats all the septage generated in the town to generate treated water, thermal energy and biochar / ash which are within environmentally responsible limits. The plant is modular and scalable while occupying a small land footprint. Biosafety is the critical parameter behind designing the plant. In addition, the system works in a diverse range of weather conditions and has been beneficial for the town of Narsapur since January 2018.

Social Aspect
Perspective towards the technology/plant: Positive



Low footprint
Modular and Scalable
Biosafe treatment process for solids and liquids
No minimum plant capacity required for operation. Even 1 truckload is sufficient
Setup time in 6-7 months from signing of agreements

Requires Electricity (Grid / DG) and skilled manpower


Picture annexure:

Containerized Thermal FSTP at Narsapur