Comparing the Effectiveness of Two Carbon Dioxide Strippers in Reducing Costs for Struvite Crystallization

In this study, two CO2 strippers were tested to determine their effectiveness in reducing caustic use during phosphorus recovery by struvite crystallization. The strippers, a compact media type and a cascade type, were connected to two identical struvite crystallizers and operated under different operating conditions at Lulu Island Wastewater Treatment Plant (LIWWTP). Both the strippers had reasonable caustic savings, compact media stripper efficiency ranging from 36-43% and the cascade stripper ranging from 26% to 46%, depending on the operating conditions. Both strippers showed low efficiency in ammonia stripping, with the compact media stripper having a slightly higher efficiency.