Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


Carleton Thesis.pdf (2.28 MB)

ETD Abstract Container

Abstract Header

Evaluation of Alum-Based Water Treatment Residuals to Adsorb Reactive Phosphorus

Carleton, George J
http://rave.ohiolink.edu/etdc/view?acc_num=akron1554238971551785

Abstract Details

2019, Master of Science in Engineering, University of Akron, Engineering.
Excess phosphorus (PO4) levels in waterways can lead to eutrophication. A low-cost measure to reduce PO4 levels may be to use Water Treatment Residuals (WTRs), which are otherwise shipped to a landfill or stockpiled in a drying field for blending and future land application. Decreasing the PO4 concentration entering Lake Rockwell, the City of Akron Water Supply’s drinking water reservoir, would aid in the prevention of harmful algal blooms. The water plant currently produces approximately 16,000 tons/yr of WTRs. Two WTRs were selected for this study: an alum-based WTR (Al-WTR) and an alum-based WTR augmented with powdered activated carbon (PAC-WTR). The hypothesis was that the Al-WTR will have better PO4 sorption than the PAC-WTR. Batch isotherm and continuous flow column experiments were performed to assess the specific adsorptive capacities under differing conditions. Variables included different isotherm temperatures, static vs. dynamic desorption, and distilled vs. raw water desorption. The continuous flow through column experiments estimated the PO4 uptake of both WTR. Results were then used to determine the variety of WTR best suited for PO4 sequestration. The necessary mass was then identified for use in Eckert’s Ditch, a tributary flowing into Lake Rockwell, the original receiving source waters of the WTR material. Both the Al and PAC-WTR exhibited the ability to sorb PO4 in the varying isotherm conditions. The cumulative day 28 desorption step qe for the Al-WTR was 39.93 mg-PO4/kg-WTR, significantly (p < 0.05) greater than the PAC-WTR value of 24.95 mg-PO4/kg-WTR. A higher qe value indicated greater PO4 sorption, as more was bound to the WTR (qe). The continuous flow column experiments predicated a theoretical PO4 uptake for the Al-WTR of 9.00 mg-PO4/g-WTR, and 7.14 mg-PO4/g-WTR for the PAC-WTR. There was no apparent threat of PO4 desorption from either the Al or PAC-WTR. The results of this study confirmed the hypothesis that the Al-WTR had a superior PO4 sorption ability. This supported the recommendation that the Al-WTR should be used in the full-scale system. A cartridge was designed to house the WTR in the full-scale remediation system. The system will contain eight gates, and each gate will house four cartridges in a 2x2 matrix. The dimensions selected for the cartridge were 12” length x 12” height x 3” thick. The cartridge will be 3D printed by FATHOM, using a food grade certified, biocompatible polycarbonate material. A dual-screen polyester mesh will sit inside each cartridge and contain the WTR. The outer screen will have a nominal pore diameter of 120 µm and the inner screen 53 µm. This study found that the use of WTR successfully reduced PO4 concentrations. The proposed solution was a system of cartridges containing Al-WTR-filled mesh bags. As the water will flow through the mesh bags, the WTR will sorb PO4 in the water, reducing the concentration. This will create a beneficial reuse of the WTR material, in addition to lowering treatment costs for the City of Akron Water Supply.
Teresa Cutright, Dr. (Advisor)
Donald Ott, Dr. (Other)
141 p.
Civil Engineering
Water Treatment Residuals; Reactive Phosphorus; Alum; Adsorption

Recommended Citations

Citations

  • Carleton, G. J. (2019). Evaluation of Alum-Based Water Treatment Residuals to Adsorb Reactive Phosphorus [Master's thesis, University of Akron]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=akron1554238971551785

    APA Style (7th edition)

  • Carleton, George. Evaluation of Alum-Based Water Treatment Residuals to Adsorb Reactive Phosphorus. 2019. University of Akron, Master's thesis. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=akron1554238971551785.

    MLA Style (8th edition)

  • Carleton, George. "Evaluation of Alum-Based Water Treatment Residuals to Adsorb Reactive Phosphorus." Master's thesis, University of Akron, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1554238971551785

    Chicago Manual of Style (17th edition)

akron1554238971551785
215
© 2019, all rights reserved.
This open access ETD is published by University of Akron and OhioLINK.