What is the purpose of controlling the flow rate at the inlet of the pretreater in saline water?
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What is the purpose of controlling the flow rate at the inlet of the pretreater in saline water?
This post was last edited by Du Xiaoping on 2015-9-21 at 14:48. Put simply, the preprocessor can be compared to a person; the input volume is like that person’s appetite – too much and it causes discomfort, too little and it leads to hunger.
So from a process perspective, then? Is controlling the flow rate to extend the reaction time?
From a process perspective, an excessive flow rate that exceeds the capacity of the equipment can lead to the clouding of the brine, resulting in quality issues with the brine. In severe cases, this can affect the electrolyzer and cause contamination of the ion exchange membrane. This is because the magnesium hydroxide precipitate appears as flocs, and these flocs adhere to the surface of the membrane, causing a sharp decline in its performance. If the flow rate of brine entering the membrane is not reduced, the levels of calcium and magnesium in that brine will exceed acceptable limits significantly; this in turn will result in excessive levels of calcium and magnesium in the brine exiting the resin tower. If such brine enters the electrolyzer, the cell voltage and current efficiency will drop sharply, with serious consequences.
As a supplementary point, when the flow rate is low, the reaction time definitely increases, as the fluid stays inside the equipment for a longer period of time. This is beneficial for the equipment and for the quality of the brine. However, a low flow rate means lower system load as well as reduced product output. The cost per unit is increased, and power consumption also goes up as a result. So, a low load is also not cost-effective.