MBBR Retrofit Upgrade Kit for Existing Latin American Wastewater Treatment Plants Our PE01-MBBR retrofit upgrade kit enables existing conventional activated sludge (CAS) wastewater treatment plants in Latin America to be converted into high-capacity MBBR (Moving Bed Biofilm Reactor) systems without constructing new basins or interrupting plant operations. Each MBBR retrofit kit includes biofilm carriers, SS304 wedge wire retention screens, aeration system modifications, and