Dr. Mitra has 25 years of domestic and international work experience (13 years in India and 12 years in USA) in wastewater. He is an International Wastewater and Sludge (Biosolids) Treatment Expert and had been recognized as a “Who’s Who” in Water & Wastewater. He is a registered Professional Engineer (PE) in the State of Virginia, USA.

Dr. Mitra has designed and worked on hundreds of Wastewater Treatment Plants (WWTPs), Sewage Treatment Plants (STPs), Effluent Treatment Plants (ETPs), and Sludge Treatment. He is an expert technologist in Biological Nutrient Removal (BNR and ENR) employing mainstream MBBR, BAS, IFAS, MBR, SBR, Activated Sludge, MLE, A/O, A2O, 3-stage and 5-stage Bardenpho process, sidestream DEMON/Anammox process and Anaerobic Treatment for BOD, Nitrogen and Phosphorus removal in WWTPs, STPs, ETPs, and CETPs. Expertise in Sludge (Biosolids) Treatment includes Anaerobic Digestion, Advanced Anaerobic Digestion, Thermal Hydrolysis Process (THP), and Aerobic Digestion Technologies with/without Power Generation and producing Class A and Class B Biosolids. Dr. Mitra has also been a consultant/advisor to several Industries and Fortune 500 companies (e.g., Reliance, Tata Companies, Reliance, Unilever, Nestle, etc), Consulting Companies (e.g., KPMG, Ernst and Young, etc), EPC companies, Municipalities, State and Central governments in India and USA and worked on projects funded by World Bank, Asian Development Bank, and Japan International Cooperation Agency (JICA). He has provided full-time consulting services to the United States Environmental Protection Agency (EPA) for several years developing various wastewater regulations, policies, and technologies for the USA).

For the last 10 years, Dr. Mitra has worked in a Leadership Position as Director/Vice-President heading Business Development, Proposals, Technology & Process, Design & Engineering in leading Water and Wastewater Companies. Companies worked include CH2M Hill/Jacobs (USA), Tetra Tech (USA), World Water Works (USA), Cambi (Europe), NJS Consultants (Japan), Toshiba Water (Japan), Ion Exchange Ltd, and Praj Industries.

Dr. Mitra has completed B.Tech in Chemical Engineering from IIT, Kharagpur, India, MS in Environmental Engineering from Vanderbilt University, Tennessee, USA, Ph.D. in Environmental Engineering from Lehigh University, Pennsylvania, USA, and MBA in Finance from Virginia Tech, Virginia, USA. He has authored several books and papers and is a member/advisor to several leading water & wastewater associations and organizations. He is an invited speaker for several domestic and international conferences, seminars, workshops, universities, companies, and research organizations.

Dr. Ninad Gujarathi is a Chemical engineering professional with leadership experience in R&D, Techno-commercial, Manufacturing, and Business roles, with a proven track record of evaluating, conceptualizing, innovating, developing, scaling up, delivering process & business solutions, and business growth. He is also a Subject matter expert in climate change mitigation solutions, biofuels, biochemical engineering, bioprocess engineering, wastewater treatment, design & scale-up of unit operations and processes from concept to commercial scale, in bioprocess applications.

After completing his Btech In Chemical Engineering from India in 2000 he went on to pursue higher Academic goals with a Ph.D. in Chemical Engineering from Colorado State University in 2005.

Some of his Key Projects/External Representations and Patent Holdings Include


Conceptualized, developed, and designed (process design) the first-of-its-kind (patent-applied) algae-based wastewater treatment solution to mitigate all aqueous effluent streams at the site. Saved millions of pounds in CAPEX-OPEX and carbon emissions for the manufacturing site.

Conceptualized & designed (2012-13), commissioned (2016), demonstrated (2017), and operated (2017-Aug’2018) the world’s first integrated, end-to-end, large demonstration plant for biocrude production using marine microalgae produced from CO2.

Successfully secured funding as a co-Principal Investigator from RIL in the United States Department of Energy (US DOE) sponsored PACE (Producing Algae for Chemicals & Energy) project in 2015.

Participated as a co-Principal Investigator from RIL in the US DOE-sponsored NAABB (National Alliance for Algae Biofuels & Bio-products) from 2011-2014.

In 2009, PRAJ contributed heavily towards the preparations of the Indian Prime Minister’s Convoy to Copenhagen Summit. Was a vital member of the team that conducted, compiled & presented life cycle analysis studies on a few renewable energy options, to the PM’s Convoy.

In 2005, conceptualized, networked, compiled, and successfully bid for a proposal for a Joint Indo-US Centre of Excellence for Bioremediation at Agharkar Research Institute (ARI). This project was funded by the Indo-US Science & Technology Forum (IUSSTF).


Ninad Gujarathi + 5 team members at Johnson Matthey Taloja. The algae-assisted effluent treatment process for wastewater from precious metal refining processes. (CBR Number: 31306; CBR date: 24-08-2021; filed with Patent Office, Government of India).

Avinash Sinha, M. Sairam, Ninad Gujarathi, Ashwin Gajra. A method for separating solid particles from a water body. Pub. No.: WO/2016/088057 International Application No.: PCT/IB2015/0592895.

Linden and Gujarathi. Aquatic plant exudates and hairy root cultures for phytoremediation of antibiotics in water and wastewater. (Provisional US patent applied on 16th March 2005; Attorney Docket No. 100-4P)