Simultaneous desorption–crystallization of CO2–CaCO3 in multi-stage flash (MSF) distillers

In this work, the desorption–crystallization of CO2–CaCO3 in MSF distillers was simulated by coupling mass transfer with chemical reaction and correlating the CaCO3 crystallization rates to the CO2 release rates. The model was applied to two 20-stage reference MSF once-through and recycles distillers. The CO2 release rates decreased exponentially from the first stage to the last stage. The CO2 release rates increased with increasing top brine temperature (TBT) and so CaCO3 deposition rates did. The CaCO3 deposition rates increased by 76.9, 102.5 and 123.0 g per ton distillate at 90, 100 and 110 °C, respectively. This corresponded to fouling resistance of 0.64, 0.83 and 1.00 m2K/kW, respectively. The results were fully discussed and interpreted.