| 摘要 |
PURPOSE:To detect surely the salt water level and the salt water concentration in a salt water tank, which contains the salt water used in regeneration of ion exchange resin, with a simple constitution. CONSTITUTION:A salt water tank 13 is connected to a processing container 11, which contains ion exchange resin for removing the hardness portion of raw water, contains the salt water to be supplied for the regeneration of the capability of the ion exchange resin and supplies the raw water after the supply of the salt water. The change in liquid pressure in the salt water tank 13 is detected at the position lower than the lower-limit position of the water-level fluctuation in the salt water tank 13. Whether the water level in the salt water tank reaches a preset reference water level or not, is detected at the same time. The water level and the concentration of the salt in the salt water tank 1 are obtained by an operation processor 20 based on the change in salt water pressure. At the time of the reaching the reference water level, the water level obtained by the operation processor 20 is calibrated to the reference water level. At the same time, the salt water concentration obtained by the operation processor 20 is calibrated based on the detected pressure value at this time point. |
