10.21.2022  |  News

Bhargavi (Gavi) Subramanian Co-Authors Water Research Foundation Project Report


The WFR-funded research project studied the quality of biogas with various co-digestion feedstocks


Kennedy Jenks announced that Bhargavi (Gavi) Subramanian of Kennedy Jenks participated in a Water Research Foundation (WRF)-funded research project early this year, studying the quality of biogas with various co-digestion feedstocks. WRF recently published report no. 4892, “Quality of Biogas Derived from Wastewater Solids and Co-digested Organic Wastes – A Characterization Study,” co-authored by Subramanian.

The study is unique in that it relates the role of sludge, co-digestion waste characteristics and biogas quality, and provides better guidance to utilities implementing the process to supplement energy production while minimizing waste. According to the US Environmental Protection Agency, taking advantage of underutilized digester capacity through co-digestion can increase energy generation from anaerobic digestion of wastewater-generated solids In California alone there are almost 140 wastewater treatment facilities that utilize anaerobic digesters, with an estimated excess capacity of 15-30%.

Since the quality of the high-strength wastes added to the anaerobic digesters for co-digestion can vary, the resulting biogas quality can be inconsistent, presenting regulatory challenges. This study alleviates some of the challenges by analyzing the impact of the addition of HSWs on biogas quality from anaerobic digesters.

Practical application of the scientific data will help utilities identify and adjust organic waste loading to the digesters based on co-digestion waste quality and quantity to estimate emissions more accurately from anaerobic digesters, understand conditioning/pretreatment of raw biogas, and support the air quality permitting process for co-digestion.

Understanding the effects identified in the study can help WRRFs properly plan co-digestion programs, including selecting the right type and amount of HSWs, identifying the treatment requirements, performing cost-benefit analyses, and complying with regulatory requirements. The information will also help regulators develop appropriate requirements for air quality compliance.

Completing early phases of the study during the height of the pandemic required exceptional diligence and dedication to work within imposed constraints without sacrificing quality.

Access the report.


About Kennedy Jenks 
Kennedy Jenks is a leading water and environmental engineering firm that serves public agencies and industrial clients with over 425 employees nationwide. The employee-owned firm delivers innovative design, construction and technology solutions for water, industrial and environmental projects across the United States.



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