Mehrdad, Mahsa

Mahsa is a water/wastewater project engineer with 10 years of wastewater industry experience. Her primary focus is on biological treatment processes with vast experience on supplemental carbon addition to enhance denitrification and EBPR processes. She has been involved in process operational evaluation, design and modeling of several wastewater treatment facilities since joined HDR.

Titles from this speaker

Glycerol Driven EBPR Correlated with Tetrasphaera Enrichment

Abstract

Enhanced biological phosphorus removal (EBPR) is considered a potentially efficient and economical process to meet stringent phosphorus (P) discharge requirement in wastewater treatment plants (WWTPs). The success of EBPR depends on the presence of adequate organic compounds in the influent wastewater. In plants with low influent organics, addition of an external carbon source is necessary to support both denitrification and EBPR. In recent years, glycerol, has obtained great attention as a non-corrosive and economical alternative supplemental carbon source for EBPR process. Many facilities with different influent characteristics, configurations and anaerobic retention time have observed improvement in the EBPR process after glycerol addition. Although utilization of glycerol has been increased in WWTPs, the number of studies investigating its role on EBPR process is limited. The overall goal of this study is to investigate glycerol driven EBPR process and develop effective operation criteria. To achieve the objectives, a survey of full scale EBPR facilities utilizing glycerol as supplemental carbon source, batch testing and 16S rRNA gene amplicon sequencing were conducted. The effect of glycerol on phosphorus release and uptake kinetics was evaluated via full scale assessment and batch testing. Microbial composition of various glycerol acclimated sludge samples was assessed to identify a correlation between glycerol usage and the growth of different PAO groups. This study aims to propose an anaerobic metabolic model for PAOs with glycerol as the carbon source.

The following conference paper was presented at WEFTEC 2021, October 16-20, 2021. To read the full abstract, see "Abstract" tab below.

SpeakerMehrdad, Mahsa

Presentation time

11:10:00

11:20:00

Session time

11:00:00

12:00:00

SessionTo Ferment or Not to Ferment: Experiences with Carbon Management, Addition, and Generation for Nutrient Removal

Session number418

TopicFacility Operations and Maintenance, Municipal Wastewater Treatment Design, Nutrients

Author(s)

Mahsa Mehrdad

Author(s)M. Mehrdad1; S. Ledwell1; R. Coleman1;

Author affiliation(s)Environmental Operating Solutions Inc, Pocasset, MA1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2021

DOI10.2175/193864718825158131

Volume / Issue

Content sourceWEFTEC

Word count8

Description: The Big One That Did Not Get Away: Pilot Testing to Reach 12 µg TP/L in a...

The Big One That Did Not Get Away: Pilot Testing to Reach 12 µg TP/L in a Hatchery Effluent

Abstract

In order to comply with the new ultra-low effluent phosphorus monthly limit of 12 µg/L, Powered Mill will, once completed, operate a state of the art water treatment plant with an upstream fish hatchery. Pilot testing completed earlier in 2022 included ultrafiltration with and without coagulant addition, ion exchange, and adsorption. The results showed that any individual technology was not capable of reliably meeting the phosphorus limit, but a combination of technology solutions could achieve the 12 µg/L limit. While the final selection is pending, the combination of ultrafiltration and downstream adsorption did meet the effluent limit while requiring minimal operator attention or chemicals; both of which are especially relevant in such a remote location. The pilot testing highlighted again the known challenges with measuring phosphorus at forensic levels. Split samples analyzed by different labs showed deviations as much as 100% between two results. This impacts both the evaluation of pilot results as well as future compliance monitoring and process control.

To meet the new effluent phosphorus limit of 12 µg/L at Power Mill hatchery, pilot testing evaluated ultrafiltration with and without coagulant addition, ion exchange, and adsorption. Results indicated that individual technologies couldn't consistently meet the phosphorus limit, but a combination of solutions proved successful. Specifically, combining ultrafiltration and downstream adsorption achieved the desired limit with minimal operator attention or chemical usage.

SpeakerMehrdad, Mahsa

Presentation time

08:30:00

08:50:00

Session time

08:30:00

10:00:00

SessionFood and Aquaculture Wastewater Treatment

Session locationRoom S501d - Level 5

TopicIntermediate Level, Nutrients, Research and Innovation, Sustainability and Climate Change

Author(s)

Mehrdad, Mahsa