Editor's note: TPO Editor Ted Rusleh is attending WEFTEC 2016 in New Orleans. Here are a few of the newsworthy topics from the show floor.

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In WEFTEC's opening general session, Water Environment Federation president Paul Brown stressed the need to inspire young people to explore water careers and invest in young professionals’ advancement.

WEF clearly is practicing what it preaches. On Monday, Sept. 26, from 1 to 4 p.m., the association held a Students & Young Professionals Networking and Career Fair. It was heavily attended; all 24 exhibits were busy. The exhibitors included major clean-water and sanitation districts as well as several of the nation’s top engineering consultancies with specialties in water and wastewater.

It was part of a WEFTEC Monday program that also included a Student Design Competition, Students & Young Professionals Committee Meeting, Black & Veatch Student Appreciation Night, and a Young Professionals Networking Reception.

The events aimed to promote participation, provide networking opportunities and encourage continued involvement in the industry.

MABR works: Chicago district proves it on one-year full-scale pilot study

Membrane aerated biofilm reactor technology lived up to its promise of space-efficient nutrient removal and low energy consumption in a year-long pilot study conducted by the Metropolitan Water Reclamation District of Greater Chicago.

Thomas E. Kunetz, P.E., the district’s assistant director of engineering, described the project and its results in a technical session Monday, Sept. 26, at WEFTEC. A full-scale 500,000 gpd MABR module operated for a year at the district’s 230 mgd (average) O’Brien Water Reclamation Plant in Skokie, Ill.

In the study, the MABR unit reduced aeration demand by 29 percent versus conventional activated sludge treatment. It also demonstrated that the technology could remove phosphorus to meet an expected future permit limit of 1.0 mg/L without the addition of new tankage. The process achieved simultaneous nitrification and denitrification in a small footprint.

The district was challenged by the impending phosphorus limit and by a shortage of space in a landlocked treatment facility. Before proceeding with the pilot, the district and the MABR vendor modeled its performance against an expansion of conventional treatment and an advanced oxidation upgrade. The modeling indicated the MABR process could meet the phosphorus limit without affecting compliance with TSS and other existing permit parameters.

The MABR process suspends cassettes of gas transfer membrane fibers in an existing aeration basin. Air is delivered from inside the membrane filters, delivering oxygen by diffusion to a biofilm that attaches to the membranes’ outer surfaces. This configuration increases the inventory of biomass in the system and thus intensifies the biological treatment process, yet requires as little as one-fourth the energy required for fine-bubble aeration.

For the pilot project, the district installed a full-scale ZeeLung MABR cassette (GE Water & Process Technologies) in a sidestream configuration. The test ran for a year ending in June 2016. Installation was accomplished simply by immersing the membrane unit in the plant mixed liquor for biofilm inoculation. The biofilm was fully established in four weeks.

Kunetz observed that the MABR process “offers an innovative way for us to meet future regulations for nutrient removal within the plant’s existing footprint. In addition, the decreased energy needed to treat the water helps us move toward our goal of becoming energy neutral by 2023.”