Chelsey Shepsko is an Environmental Engineer with GHD Services, Inc. in the Philadelphia area. She has a B.S., M.S. and Ph.D in Environmental Engineering from Lehigh University. Her specialty involves water/wastewater physicochemical and bioremediation processes. Her work on emerging contaminants includes ion exchange capabilities of hybrid ion exchange materials with PPCP constituents and bioremediation of the brine waste.
Selective Removal of Ibuprofen Simultaneously in a Nutrient Removal and Recovery Hybrid Ion Exchange (HIX-NP) Process Treating Secondary Municipal Wastewater
Implementation of nutrient removal and recovery technology in municipal plants will mitigate eutrophication effects that occur when nitrogen and phosphate-laden treated municipal water is discharged to surface waters at levels that allow for the production of algal blooms and their resulting detrimental effects to water bodies (hypoxia, toxicity, loss of habitat, etc.). At the same time, pharmaceuticals and personal care products (PPCPs), e.g. prescription drugs, supplements, cosmetics, are discharged to wastewater treatment plants originating from human waste in residential wastewater and remain untreated upon discharge to surface waters due to a lack of water quality standards. In this study, we present a hybrid ion exchange (HIX-NP) process that (i) allows near-complete recovery of nitrogen and phosphate, (ii) removes ibuprofen without inhibition of nutrient recovery, and (iii) uses CO2 as the only regenerant chemical that is sequestered finally as CaCO3(s). One shallow shell weak-acid cation exchanger (SS-WAC) and a hybrid anion exchanger (HAIX-NanoZr) with specific affinity toward nitrate phosphate, and ibuprofen form the heart of HIX-NP recovery process. Studies were conducted using secondary wastewater from the Bethlehem, PA plant and CO2 was the only regenerant used replacing the need for other mineral acids. HIX-NP accomplished near-complete removal of phosphate and nitrate and their recovery in high purity, while ibuprofen was removed to near-zero levels (>95% removal) for 800 bed volumes.