Water softening method using thermally regenerable ion exchange resin
Certain thermally regenerable ion exchange resins are operated in a novel process to soften and demineralize aqueous solutions. The process includes countercurrent thermal regeneration of the resin.
Patent number: 4184948 KUNZ METHOD AND APPARATUS FOR SOFTENING OR DESALTING WATER BY ION EXCHANGE
In an ion exchange apparatus and method for the softening and/or desalting of water by countercurrent flow, an ion exchange column, containing alternately cation exchange material and anion exchange material, is provided with a pair of regenerating columns being connected to said exchange column, with one receiving spent cation material and the other spent anion material, and a washing column connected to each regeneration column and to the exchange column so that upon the regeneration and washing of the cation and anion exchange materials, each will be passed to their respective zone.
Patent number: 3679581 Water softener control
A water softener control includes a cell of sampling resin which received periodic samples of water which has passed through a major portion of the softening bed. The sampling resin changes volume when it becomes exhausted and the change in volume is employed to initiate regeneration of the softening bed. At the start of the regeneration cycle, regenerative fluid is delivered directly to the sampling resin as well as to the softening bed. The delivery to the sampling resin is through a control valve which is piloted by pressures at a venturi injector which is used to withdraw regenerative fluid from a brine tank. A vacuum operated control valve which is responsive to the closing of an air check valve in the connection between the injector and the brine tank may be employed to positively close the connection from the sampling cell to the injector when the supply of regenerative fluid is exhausted.
Patent number: 4385992
| 
