| 摘要 |
A raw water hardness value is taken at intervals of time or volume, during flow to the treatment vessel (5, 6) containing softening agent. This is used to calculate depletion of filtration capacity in the vessel, at corresponding intervals. Note: in this context, the term filtration refers specifically to softening capacity. The hardness value of the raw water supplied, is measured after extraction of predetermined quantities (V) of treated, soft water flowing from the vessel. Alternatively a time basis is employed. A series of successive measurements of filtration capacity (Kn) is taken. Portions of capacity are added to obtain the total depletion in filtration capacity (Kg n). This is related to the original filtration capacity (Ko). From these values (Kg n, Ko) a realistic filtration capacity (Kr n) is calculated, and when this value reaches zero (or a given minimum value), exhaustion of the filter is indicated. An independent claim is included for equipment determining filtration capacity depletion in water softening plant. |
