New High Rate Bio-methanation Technology for Integrated Treatment of Sewage & Organic Solid Waste Useful for Decentralized Applications

A new high rate biomethanation technology for the integrated treatment of sewage and organic solid waste and concomitant generation of biogas and bio manure can treat groundwater and wastewater and convert it to potable water. It can be used for sewage and organic solid waste treatment with decentralized applications in various parts of India.

Solid and liquid wastes are major challenges faced by big cities as also for the rapidly urbanizing areas, and sustainable technologies are needed for tackling them. An integrated treatment of sewage along with organic solid waste in India could help evolve a sustainable technology to overcome the solid and liquid waste disposal issues.

Dr. A. Gangagni Rao, Chief Scientist, and Dr. S. Sridhar, Senior Principal Scientist, CSIR- Indian Institute of Chemical Technology (IICT), have jointly developed this high rate biomethanation technology based on Anaerobic Gas lift Reactor (AGR) Technology for the treatment of organic solid waste and concomitant generation of biogas and bio manure along with Nanofiltration (NF) setup

This integrated and sustainable sewage and organic solid waste treatment system can be used for treating groundwater and wastewater and generating potable and reusable water, respectively. The technologies supported by the ‘Waste Management Technology’ program of the Department of Science & Technology (DST), Govt. of India have received national patents individually.

These AGR and NF membrane technologies at the Technology Readiness Level of 9 have been tested in the field. According to Dr. Rao and Dr. Sridhar, urban and local bodies and gated communities comprising around 50,000 to 1,00,000 population could benefit from this technology. Instead of sending the organic solid waste and liquid waste to the common bigger facilities in the city, the same waste could be treated at source only in decentralized manner.

An integrated model plant comprising of AGR and NF technologies has been established at CSIR-IICT, Hyderabad, for the simultaneous treatment of sewage (100 liters/day) and organic solid waste (250 kg/day) for the generation of value-added products such as biogas, bio manure, and reusable water. The integrated technology is field-tested and working continuously for the past two years.

This integrated approach of sewage and organic solid waste treatment could be exploited anywhere in India, where municipalities comprising around 50,000 to 1,00,000 population generate approximately 2 to 4 million litres per day of sewage and 5 to 10 metric tons per day of organic solid waste.

AGR patent Number: 307102 & NF Patent Number: 7314606

It incorporates best features of high rate anaerobic digester. This technology encompasses novel pre and post-processing mechanisms Advanced digester design Smaller digester volume Easier to scale-up and multiplication Semi-automatic plant operation Higher biogas yield Generation of organic fertilizer Locally available enriched microbial consortia Remunerative for decentralized application Distributive biogas plants at waste generation source Use of by-products will make the plant sustainable

Requires small footprints and less operating and maintenance costs Efficient in producing good quality water free of contaminants such as heavy metal ions, hardness, dissolved solids, turbidity, and bacteria, etc. without loss of  minerals The membrane in the system is indigenously synthesized and made of  hydrophilized polyamide NF membrane The vertical placement of spiral wound membrane modules in the system allows stable plant operation for longer time periods without the use of chemical cleaning agents.

For more details, please contact Dr. A. Gangagni Rao, Chief Scientist, CSIR-IICT, Hyderabad ([email protected] or [email protected], Mobile)