BioWin Modeling\nComparisons of Municipal Wastewater\nPhosphorus Recovery between Brushite and Struvite

New technologies hold promise for advancing wastewater\ntreatment\nby enhancing phosphorus (P) removal and recovery. The CalPrex precipitation\nreactor treats acidogenic digest with lime to precipitate brushite,\nrecovering P in a form suitable for land application while reducing\nthe buildup of nuisance struvite. To assess CalPrex performance in\ndifferent scenarios, including its interaction with existing Ostara\n(struvite) reactor installations, we adapted a BioWin configuration\nof a municipal wastewater treatment plant hosting both a pilot-scale\nCalPrex reactor and a full-scale Ostara reactor. Our modeling work\naimed to estimate the impact of reagent dosage on plantwide P recovery.\nWhen used alongside the Ostara process, CalPrex captured 36% of influent\nP, resulting in a 48% reduction in struvite precipitates in the anaerobic\ndigester and a 12% decrease in the overall sludge production. As the\nsole P removal process, CalPrex was predicted to capture 41% of influent\nP, leading to a 33% decrease in anaerobic struvite precipitates and\nan 8% reduction in total sludge production compared with the current\nconfiguration with the Ostara reactor. This study represents the first\nattempt to model CalPrex interactions with other wastewater treatment\ntechnologies and can inform wastewater operators seeking to expand\ntheir P management systems.