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It was assumed that the effluent pH of limefeeder is constant at 12.4, and the ratio of the flow rate between lime feeder and plant changes from 10^(-5) to 0.01. Other values in the calculations were kept the same as in the previous calculation.
A hardness of 0.02g/L acts as a good buffer for the system (see figure 1). From figure 1 it is observed that when the flow rate changes, the change of pH is not so dramatic but the case is much different if the hardness decreases. For instance, for the raw water of CUATRO COMUNIDADES for which the inital ANC is 7.65mg/L, using ,and we assume the same initial pH(6.5), using the same method gives a much steeper slope (see figure 2).
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