Renowned for its robust knowledge base and expertise, the division excels in cutting-edge biological treatment systems, with a particular focus on anaerobic microbial processes. Many of the breakthrough technologies from the NIIST ETD have been licensed to multiple companies and are actively operational across various industrial sites, delivering impactful results on the ground.

This vertical specializes in comprehensive waste management solutions, covering

A. Solid waste treatment
B. Liquid waste (effluents and drinking water) Treatment, and
C. Gas purification (odour control).

A. Solid Waste Treatment:

Solid-State Anaerobic Digestion: A unique Bio-methanation process, where the TS content of the input material (like food waste) is >15%. Compared with the conventional biogas plants in India (wet anaerobic digestion process), the solid-state AD process has many advantages like compact size, very low water footprint (no water mixing with waste), high biogas yield, less discharge slurry etc. NIIST has major implementations of the technology like the Trivandrum International Airport.

Bio-drying Technology for Municipal Solid Waste (MSW): The Bio-drying or Biological-Mechanical-Treatment (BMT) technology is an innovative approach for treating high-moisture containing municipal solid waste (MSW) to make it suitable for waste-to-energy (WTE) applications. The process handles mixed MSW, including organic compounds, plastics, waste clothes, and paper, in a scientific and efficient manner.

A lab-scale (110 kg/batch capacity) studies were completed and the results are highly encouraging for the treatment of MSW under Indian conditions.

Highlights of NIIST Technology

●  Advanced energy/resource recovery technology compliant with SWM 2016.
●  Improves efficiency, shortens processing time, and recovers RDF, oil, metals, and biosolids.
●  Fully enclosed, leachate-free system with odor control via bio-filtration.
●  Reduces GHG emissions, enhances air quality, and mitigates climate change impacts.

Lab scale unit for handling MSW 110 kg/batch

Recovering high value products from Agro Residues: Recovering high value products from agro residues like waste banana stem, pineapple leaf, coconut husk, etc. Through bio-augmenation, recovering high value products like natural fibre, bioenergy and organic manure.

STP Secondary Sludge/Faecal Sludge Treatment: Detailed study on the treatment of STP secondary sludge as well as fresh faecal sludge. More emphasis on assessing the pathogen load, AMR and Antimicrobial resistance genes (ARGs) in the bio-solids and their effective treatment to recover bioenergy and organic manure.

Aerobic Composting of Organic Wastes: Aerobic composting of organic waste is one of the recommended methods as per Solid waste management rule 2016 of GOI. NIIST has developed a biomedium named JAIVAM which can accelerate the composting process, and will recover high quality organic manure from the organic wastes.

B. Liquid Waste Treatment:

Anaerobic Treatment Technology for Complex Organic wastewater: BFBR is a unique technology developed by NIIST ETD. This US patented technology is particularly developed for addressing high suspended solid (non-settling) containing wastewater. Recently NIIST commissioned one model ETP at one of the Desiccated Coconut Industries in Kasaragod, Kerala.

Model ETP at Desiccated Coconut Industries in Kasaragod, Kerala

Bio-Electro-Chemical (BEC) system for Hydrogen recovery from wastewater: Recovering Green hydrogen from organic wastewater through a specially designed BEC system. A pilot plant demonstration facility is currently operational in NIIST campus.

Decentralized / Onsite Wastewater Treatment system: NIIST has developed a unique Modular Onsite wastewater treatment technology named NOWA for the onsite treatment of wastewater. This technology is already approved by Kerala Suchitwa Mission and few companies have already licensed the technology and field units are working at different industrial sites.

Bio-Remediation Technology for Perchlorate: Perchlorate is a toxic oxy-anion (ClO4-) known to cause hypothyroidism in human. It is used mainly in space R&D, strategic sector and many industries including cracker/match box making units. NIIST has developed a bioprocess (US patented) for detoxifying the contaminant, converting into non-toxic chloride any oxygen. The technology already implemented at field for generating potable water from contaminated ground water at Keezhmad in Aluva, Ernakulum, Kerala.

C. Gaseous Waste Treatment (Gas biofilter Technology) for Odour Control:

Olfactometry for odour measurements
The dynamic olfactometer measures odour concentration using human sensory response, following international standards like EN 13725. Odorous air samples are collected in inert bags, diluted with odour-free air, and presented to trained panelists, who identify detection thresholds where odour is perceptible to at least 50% of them. Odour concentration is expressed in odour units per cubic meter (OU/m³).
Statistical analysis ensures reliable, standardized results for assessing odour impact, optimizing control systems, and meeting regulatory requirements. As India’s first NABL-accredited lab for ambient air odour measurement, CSIR-NIIST provides precise, globally compliant assessments for environmental and industrial applications.

Odour measurement through Dynamic Olfactometry

Odour control biofilter technology
CSIR-NIIST is the pioneer in odour control in the country employing a proprietary gas bio-filter technology which makes use of indigenous and locally available materials such as coir fibre and coir pith for odour control (US pat. 6,696,284). Odour control systems comprising gas bio filters developed at CSIR-NIIST have been successfully installed at several places such as fishmeal factories, fish stalls, crushed bone processing industries, waste treatment plants etc. The proprietary technology of CSIR-NIIST is easily adaptable according to the type of pollution caused by various industrial processes, with necessary customization

The Environmental Management and Geospatial Modeling Group at the Environmental Technology Division (ETD) addresses various environmental challenges and provides solutions across multiple sectors. Its key activities include:

A. Environmental Impact Assessment (EIA): CSIR-NIIST is a QCI-NABET accredited EIA consultant, recognized for its expertise across five sectors: mining of minerals, ports, harbors, breakwaters and jetties, mineral beneficiation, building and construction projects, and township and area development. NIIST has successfully provided services to major government organizations, including IREL (India) Ltd., Kerala Minerals and Metals Ltd., and the Kerala Maritime Board.

B. Geospatial Modeling and Analysis: Geospatial analysis and modeling is a key activity within the ETD, aligning with the national geospatial policy approved by the Government of India. This work supports land use/land cover analysis, environmental management planning, and route optimization. The facility is also used for thermal remote sensing of municipal solid waste to assess land surface temperatures. Geospatial modeling of the thermal environment is employed to measure greenhouse gas emission factors. The activity is also being used for the sustainable management of sediment resources and widely used for projects related to river sand mining.

C. Waste Inventories: The Environmental Management and Geospatial Modeling Group plays a pivotal role in conducting regional waste inventories, including e-waste and plastic waste. The group successfully completed an e-waste inventory for the state of Kerala and the Lakshadweep Islands ecosystem. Additionally, the group contributes to environmental assessment studies that do not require formal environmental clearance.

D. Knowledge dissemination: The group regularly conducts courses on "Remote Sensing and Geographic Information System Applications in Environmental Impact Assessment and Management." It has successfully held five consecutive courses from 2019 to 2024.
Through these activities, the group significantly contributes to environmental sustainability and the management of ecological resources.

CSIR-NIIST has established India’s first dioxin research facility under the DSIR-CRTDH project, addressing the country’s previous lack of capabilities in dioxin research and monitoring. The facility has validated critical processes, including sampling, extraction, clean-up, and isotopic dilution mass spectrometric (GC-MS/MS) quantification, earning NABL accreditation under ISO/IEC 17025:2017. It is also the first in India to validate GC-MS/MS-based analysis of dioxins and PCBs per EU 644/2017 regulations.
Recommended by the MoEF&CC for environmental clearances in sectors like waste incineration and shipbreaking, the facility uses automated systems and advanced GC-MS/MS analysis to reduce cost and time. Recognized as a National Reference Laboratory by FSSAI in 2023, CSIR-NIIST holds integrated NABL/EIC/FSSAI accreditation for dioxins, PCBs, heavy metals, and contaminants in food and feed matrices.

Advanced Research on Dioxins & POPs in Areas like-

A. Source emission assessment and formation pathways

NIIST, tasked with inventorizing unintentional POPs in India, has established test facilities for simulated open burning and incinerator emissions, generating national emission factors for dioxins and PCBs (https://doi.org/10.1016/j.jenvman.2021.114109). The team studies formation pathways, spatio-temporal trends, and air pollution modeling to define optimal technologies and emission control measures, minimizing environmental and health impacts.
Monitoring efforts focus on key emission sectors, including BMWI, HWI, WtE plants, dumpsites (https://doi.org/10.1007/s12403-021-00450-4), cement co-processing, secondary metal processing, pulp and paper industries, and E-waste/plastic recycling, to assess trends and develop mitigation strategies (https://doi.org/10.1016/j.jenvman.2022.117004).

Open Burning Test Facility (Left) and Testing of small Incinerators (RIght)

B. Exposure health risk assessment studies

Over 90% of human exposure to dioxins and PCBs occurs through food, particularly lipid-rich animal products like fish, milk, eggs, and meat. Understanding bioaccumulation and magnification trends, especially near emission sources, is crucial (https://doi.org/10.1016/j.envpol.2023.122161). Foraging animal-based food products also serve as passive indicators of contamination (https://doi.org/10.1016/j.chemosphere.2024.142078).
The team investigates contaminant fate at the environment-biota interface, trophic transfer rates, and biotransformation pathways. Expertise in environmental health and toxicology has led to the development of risk assessment models, systematic reviews, meta-analyses (https://doi.org/10.1007/s10661-024-12690-3), and ecotoxicological tests using earthworms and plants. Human biomonitoring studies, such as breast milk analysis, are also underway.

Ongoing studies on emerging contaminants

The division is keen to explore the analytical and technological challenges in the quantification and process control/ innovative removal strategies for emerging environmental contaminants such as Perfluoroalkyl Substances (PFAS), Pharmaceutical and Personal Care Products (PPCPs) such as veterinary and antibiotic drug residues, phthalates, plasticizers, microplastics, heavy metals, volatile organic compounds such as HCHO, BTEX etc.
State of the art facilities such as ICP-MS, LC-MS/MS, GC-ECD/NPD/FPD, TOC analyzer, Ion Chromatography etc have been installed at the laboratory to cater these emerging contaminants.