Water, Wastewater & Stormwater
394354 - Removal of sulfate from municipal wastewater treatment plant effluents: A review of the state-of-the-industry, opportunities, and challenges
Thursday, June 7
10:30 AM - 12:00 PM
Location: Greenway EF
Lisa Andrews, Minneapolis, MN – Barr Engineering Company; Ali Ling, Minneapolis, MN – Barr Engineering Company; Herman Dharmarajah, Mankato, MN – Bolton & Menk, Inc.; Adrian Hanson, Mankato, MN – Bolton & Menk, Inc.
The State of Minnesota is currently revising the surface water quality standard of 10 mg/L sulfate for the protection of wild rice. A revised water quality standard may result in some municipal wastewater treatment plants (WWTPs) needing to reduce the concentration of sulfate in their discharges. Historically, municipal WWTPs in Minnesota have not been required to treat sulfate to achieve compliance. This paper presents the results of the first of a two-part study commissioned by the Minnesota Pollution Control Agency through funding from the Minnesota Environment and Natural Resources Trust Fund to assess the current technologies and tools available to WWTPs to reduce sulfate concentrations in their discharges and identifies the challenges of meeting potential sulfate limits in the future. In Part 1 of the study, a wide range of established and emerging sulfate treatment technologies from the municipal and industrial sectors and source control options were reviewed, screened, and ranked to understand their advantages and disadvantages and to identify potentially feasible technologies currently available for sulfate removal. While several potential treatment technologies may be available for municipal WWTPs, several key technical challenges still need to be overcome. This presentation will also provide an overview of on-going investigations to address these challenges. Part 2 of the study (expected completion early 2018), examines the practical design, implementation considerations, and costs of select treatment technologies for use in removing sulfate in typical WWTP applications. A brief high level summary of the results of Part 2 are presented in tandem with this presentation.