Resin pressure sensor for water treatment

Abstract

An improved resin sensor which senses a change in the condition of the resin by forces acting on a receptacle for the resin. The sampling resin is utilized to indicate a change of ion or equilibrium condition of the resin when employed as an indicator for resin regeneration or end of a rinse cycle in a water softening or deionization system. The sampling resin is placed in a receptacle which will confine the expansion in volume of the resin as the resin is acted upon by a sampling or indicator liquid causing the resin to exert a force on the receptacle. The receptacle for the resin allows water to freely flow in and out while entrapping the resin therein. In one embodiment, the container is composed of screened walls and the pressure sensor is a strain gauge which is attached thereto. In another embodiment, the pressure sensor is the container and in the form of a multiapertured Bourdon tube in a fluid compartment. In both embodiments, the pressure sensor will measure the change in internal pressure of the resin as it is contacted by an indicator liquid. In utilizing the resin pressure as an indication of resin regeneration or depletion, a more accurate determination can be made. Further, by employing a sensor container in a compartment water pressure is equalized and pressure differentials for the water inside and outside of the container do not have to be compensated.