Dr.Krishnakumar B

Dr.Krishnakumar
Patents & Publications

Patents:

  1. A modular system and method for onsite wastewater treatment and resource recovery, India, South Africa, Brazil, and Germany. Filed on 13 December 2021 (PCT/IN2021/051166; WO2022130402A1). Filed in South Africa on 15 June 2023 (Patent No. ZA202306292B). Status: Pending in South Africa, Brazil, and Germany.
  2. Bacterial consortium for reducing perchlorate and/or nitrate and the process thereof, United States. Filed on 30 December 2016. Granted on 19 July 2022 (Patent No. US 11,390,547 B2). Co-inventor: Anupama V. N.
  3. Bacterial consortium for reducing perchlorate and/or nitrate and the process thereof, India. Filed on 19 January 2016. Granted on 5 September 2023 (Patent No. 449570). Co-inventor: Anupama V. N.
  4. Process for the production of violacein and deoxiviolacein pigment from Chromobacterium sp. (MTCC 5522), India. Filed on 12 March 2010. Granted on 12 January 2023 (Patent No. 417830).
  5. Process for the production of violacein and deoxiviolacein pigment from Chromobacterium sp. (MTCC 5522), Germany. Filed on 30 December 2016 (Patent No. DE112016006253T5). Published on 4 October 2018. Co-inventor: Anupama V. N.
  6. Process for the production of violacein and deoxiviolacein containing bioactive pigment from Chromobacterium sp. (MTCC 5522), Brazil. Filed on 10 March 2011 (Patent No. BR112012021846B1). Published on 8 December 2020.

Recent Publications:

  1. Sakhre, S., S, R. A., S, A., Vijay, R., & Bhaskaran, K. (2025). Physico-chemical characteristics of fresh faecal matter from a residential apartment: A short-term study conducted at Thiruvananthapuram, Kerala, India. Environmental Monitoring and Assessment, 197. https://doi.org/10.1007/s10661-024-13461-w
  2. Gopalakrishnan, S., Aparna, V. L., Shende, A. D., & Bhaskaran, K. (2025). Comparative evaluation of needle-felt coir fibre with conventional media in treatment wetlands. Journal of Water Process Engineering, 72, 107525. https://doi.org/10.1016/j.jwpe.2025.107525
  3. Gopalakrishnan, S., Dipin Nath, R. S., Shende, A. D., & Bhaskaran, K. (2024). Needle-felt coir fibre: A natural substitute for synthetic media in anaerobic fixed film reactors for wastewater treatment. Journal of Environmental Chemical Engineering, 12, 112382. https://doi.org/10.1016/j.jece.2024.112382
  4. Russel, J. G., & Krishnakumar, B.* (2023). A low-cost in-situ bioremediation process for perchlorate contaminated aqueous phase. Journal of Hazardous Materials, 442, 130035. https://doi.org/10.1016/j.jhazmat.2022.130035
  5. Sakhre, S., Ajantha, S., Bisarya, A., Vijay, R., & Bhaskaran, K. (2023). Development of a kinetics-based onsite treatment system for faecal sludge treatment and resource recovery. Journal of Solid Waste Technology and Management, 49, 320-332
  6. Suryalekshmi, V. A., & Krishnakumar, B.* (2022). Extracellular lactonase-mediated quorum quenching by a novel Bacillus velezensis. FEMS Microbiology Letters, 369(1), fnac095. https://doi.org/10.1093/femsle/fnac095
  7. Jasmin, G. R., Venkatesh, T., Nair, R. R., Sayana, C. R., Hareesh, U. S., & Krishnakumar, B.* (2021). A novel bio-physical approach for perchlorate contaminated well water treatment. Environmental Advances, 4, 100058. https://doi.org/10.1016/j.envadv.2021.100058
  8. Nair, R. R., Russel, J. G., Pradeep, S., Ajay, S. V., & Krishnakumar, B.* (2020). A novel ex-situ bioremediation process for perchlorate contaminated soil. Chemosphere, 247, 125947. https://doi.org/10.1016/j.chemosphere.2020.125947
Home

Dr. Krishnakumar B. is a native of Kollam district, Kerala. He did his B.Sc. and M.Sc. in zoology under the University of Kerala. Subsequently, in 1994 he joined CSIR-RRL Trivandrum as a CSIR-Research scholar. He pursued his research on Microbiology, and obtained his Ph.D. degree in 2000 from the University of Kerala.

In October 2000, he was awarded with the prestigious STA postdoctoral research fellowship from the govt. of Japan, and he joined National Institute for Environmental Studies, Tsukuba, Japan.

Until 2003, he continued his postdoctoral studies in Japan. In March 2003, he joined CSIR-RRL as a Fellow scientist, and later, on October 2004, he joined RRL as a permanent scientist, and presently working as Chief Scientist & Head Environmental Technology Division. He is also a Professor in the CSIR Academy.

Major Research Areas includes

  • Engineered Biological Treatment Systems for Solid, Liquid and Gases
  • Decentralized wastewater treatment systems
  • Nature Based Treatment systems
  • Waste Valorization
  • Microbial ecology
Academics & Research Experience

Academics

  • Ph.D. Microbiology (2000); Bacterial Desulphurization of Hydrogen Sulphide. Univ. of Kerala.
  • Postdoctoral Research (2000-2003) National Institute for Environmental Studies (NIES), Tsukuba, Japan.

Research Experience

  • November 2004 - Present: Scientist (various positions) in the Environmental Technology Division, CSIR-NIIST, Thiruvananthapuram.
  • Fellow scientist (2003-2004): Environmental technology division, CSIR-Regional Research Laboratory, Thiruvananthapuram.
  • CSIR-Research fellow (JRF, SRF & ESRF) (1994-2000): CSIR-Regional Research laboratory, Trivandrum.
Research & Projects

The treatment and safe management of organic wastes (both solid and liquid) is fundamental to the sustainable development of any society. These waste streams are often resource-rich and, with the right scientific interventions, can be transformed into valuable products. Our research focuses on harnessing tailored microbial systems within engineered biological platforms to recover resources such as bioenergy, high-quality reusable water, organic fertilizers, natural fibers, and other bio-based products.

Key areas of emphasis include advancing our understanding of aerobic, anaerobic, and anoxic microbial processes; designing and optimizing specialized microbial consortia; applying this knowledge to develop innovative waste treatment solutions; translating laboratory-scale findings into scalable technologies; and driving their deployment in real-world field applications.

Total Projects completed as project Leader - 46

From Govt. Agencies including DST, DBT, Jal Jeevan Mission, Airport Authority of India, RBI, CSIR, KSCSTE, KSPCB, KWA, Kerala Suchitwa Mission, etc. - 30 Nos.

Industry Sponsored R&D Projects - 4 Nos.
Consultancy Projects from Industries - 12 Nos.

Some of the significant R&D development includes-

1. NOWA (NIIST Onsite Wastewater Treatment System):

Managing wastewater from small establishments is a significant challenge. Conventional solutions, such as MBBR, SBR, DEWATS systems, suffer from key drawbacks including high capital and operational cost, space requirements, and limited efficiency.

To address these gaps, CSIR-NIIST has developed a novel, onsite wastewater treatment system named NOWA that will recover reuse quality water, bioenergy and organic manure from the wastewater. NOWA is a compact, modular, pre-fabricated design that ensures easy installation, lower capital and operational costs, and better performance compared to conventional systems.

NOWA (Patented) is a combined Anaerobic-Oxic-Anoxic microbial process, that can be integrated with Engineered wetlands for making it eco-friendlier. The NOWA technology is approved by Kerala State Suchitwa Mission, and Kerala State Rural Water Supply and Sanitation Agency (KRWSA) is promoting the field implementation of NOWA for different wastewater treatment/reuse at the panchayat level.

NOWA

2. Modular Greywater Treatment System for Homes

Greywater refers to wastewater generated from domestic activities such as bathing, washing clothes, handwashing, and kitchen use, excluding toilet waste. It constitutes approximately 80% of the total household wastewater. In a typical household of five members, about 375 litres of greywater (75.6 LPCD) is discharged daily. Given its large volume and relatively low contamination, greywater offers significant potential for treatment and reuse, especially in water-scarce regions.

CSIR-NIIST has developed a unique technology, the modular engineered wetland system for greywater treatment at homes. This will be a better substitute for the existing practice of disposing the household greywater into soak pits without any treatment. In this treatment system, an engineered microbiome and selected macrophytes under defined set of conditions will remove the contaminants in the greywater. This technology will be very useful for places with high groundwater table.

Greywater treatment system

3. Transition Pathways in Septage and faecal sludge treatments

Under the CSIR-BMBF (Indo-German) collaborative research, we have a study on “Transition pathways for solving the urban wastewater, faecal sludge and septage problem in Indian cities based on resource orientation and business models”. University of Bahuas-Weimar (lead partner), ISOE-Frankfurt and Aone-Leipzig were the German partners in this project. Two cities in India including Thiruvananthapuram and Nagpur were studied for the existing solid and liquid waste management practices and resource oriented advanced treatment options.

sludge treatment

4. Bioremediation of Perchlorate/Nitrate

Perchlorate is a toxic oxy anion (ClO4-) extensively used in arms and ammunition sector, space R&D and few industrial sectors. It is well recognized that perchlorate can adversely affect the functioning of Thyroid gland causing hypothryroidism. Our research in 2012 flagged first time in India severe ground water contamination of perchlorate (~50000 ug/L against WHO permissible limit of 70 ug/L in drinking water) at few locations in Kerala.

Subsequently we developed a microbial system and engineered process for decontaminating perchlorate into non-toxic chloride and oxygen. The technology was subsequently scaled up and demonstrated at field in Keezhmad panchayat in Kerala, India. The well water from one of the closed well (due to contamination) was pumped out and treated with our technology and drinking water generated (~2000 L/day) was distributed to the public. This project was funded by Jal Jeevan Mission (Ministry of Jal Shakti).

Water

5. Solid-State Anaerobic Digestion of Organic wastes:

Anaerobic digestion (AD), commonly known as biogas technology, is a well-established scientific method for managing organic wastes. Under anaerobic conditions, specialized microbial consortia convert organic waste into biogas and nutrient-rich organic manure. Conventional biogas plants generally use wet AD technology, where wastes are diluted with water prior to treatment. In contrast, advanced high-rate systems operate without dilution, known as solid-state or dry AD technology. Compared to conventional systems, solid-state AD offers several advantages: compact design, no water requirement, reduced slurry discharge, and higher biogas yields. CSIR-NIIST has developed a solid-state AD technology, which has been successfully implemented at multiple sites, including a 500 kg/day unit at Thiruvananthapuram International Airport.

Biogas plant

6. Engineered Microbiome for enhancing the aerobic composting:

The management of degradable organic waste poses major environmental, social, and public health challenges. Aerobic composting offers a sustainable solution, and CSIR-NIIST has developed Jaivam-an engineered microbial consortium that accelerates composting and produces high-quality organic manure. Identified through DNA sequencing, the proprietary microbes convert waste efficiently, eliminate odour, and are safe and chemical-free. The technology is licensed to two companies for mass production and field application for waste treatment.

Jaivam

7. In-situ Enzyme assisted fibre recovery from Waste Agro-residues

Waste agro residues such as banana pseudo stem, coconut husk, pine apple leaves, etc. are a rich source of natural fibre for different industrial applications. The conventional practice of fibre recovery are either mechanical or retting process, where fibre quality is compromised and the method creates many environmental problems including water and air pollution, accumulation of solid waste etc.

We have developed an in-situ enzyme assisted bioprocess for recovering cellulose rich natural fibre from agro residues. In this method specific microbial systems under controlled conditions, will digest the bulk waste releasing the natural fibre. The cellulose content in the fibre can be enhanced further to 70% through a combined microbial and chemical process. Additionally, Nano-cellulose can be prepared that can be used for different high end applications including biomedical, energy fields.

Technologies/Processes
  1. NOWA (NIIST Onsite wastewater treatment system); A modular, onsite wastewater treatment cum resource recovery system for organic rich wastewater. This patented technology is approved by Kerala Suchitwa Mission and Promoted by KRWSA. Technology available for licensing.
  2. JAIVAM; Engineered Microbiome for accelerating composting of organic wastes. This microbial inoculum can be used for Bin composting or other composting devices. Kerala Suchitwa Mission recognized inoculum. Technology available for licensing.
  3. Modular Onsite Greywater Treatment system for Homes; This is a unique technology for treating the greywater from homes. This will help to recover reuse quality water from household greywater. Patented technology. Technology available for licensing.
  4. Bioremediation technology for perchlorate/nitrate contaminated aqueous phase. US patented technology. Demonstrated at field. This technology can be used for decontaminating perchlorate contaminated wastewater. Technology available for licensing.
  5. An ex-situ remediation process for soil contaminated with perchlorate. Process demonstrated up to pilot scale. Technology available for licensing.
  6. A fermentative process for the production of Violacein, a high value bio-active compound. US, EU, & BR patented process. Technology available for licensing.
  7. AIR SANITIZER; Stand-alone air disinfection system for controlling aerosol mediated transmission of diseases. The technology licensed to two companies.
Ph.D., M. Tech/M.Sc. Students
  • Ph.D. Thesis awarded 7
  • Ph.D. Research Ongoing 6
  • M Tech / M Sc Thesis supervision ~40