TW Moses ActiCarb Improvements

The TW Moses water treatment facility uses a high rate ballasted flocculation activated carbon (ActiCarb) system to help remove taste and odor components from raw water. The system is used intermittently due to seasonal needs. Due to the complexity of the system, the polymer feed system has been identified as an area of improvement.

The existing polymer feed system operates in a batch mode based primarily on timers and level sensors.  It uses dry polymer and requires a mixing system to prepare the polymer for use but its reliability is questionable.  The students will review the system to identify other options for the mixing and feed system as well as explore switching to a full liquid polymer system. 

The Acticarb system effluent is discharged directly to the sand filters.   During initial startup and tuning of the system, effluent solids can blind the sand filters.   There is a desire to re-route the Acticarb effluent to the “low basin” in order to settle the excess solids prior to the sand filters.  Students will evaluate the hydraulics of the proposed flow path to determine if gravity flow is practical or if a pump station will be required.  Students will also evaluate required modifications to influent and effluent structures in order to accommodate the changes.  

 

Senior Design Team update:

The ActiCarb team is working with Citizens Energy Group to optimize the activated carbon polymer system at the T.W. Moses Water Treatment plant. The team is looking into methods for improving the system’s ability to remove high levels of taste and odor causing Geosmin and Methyl-Isoborneol (MIB).  They are also helping T.W. Moses to become compliant with turbidity limits. In order to achieve this, the team is running jar tests that examine the effectiveness of different polymers on solid settling in the activated carbon system. Additionally, the team is conducting a hydraulic analysis to determine whether changing the flow pattern at T.W. Moses will allow for better settling results that will meet the turbidity requirements of the plant. The team is excited to help Citizens Energy improve the drinking water quality of the Indianapolis area.