Abstract:
A method for regenerating strong-base anion exchange resins utilizing a sequential chemical displacement technique with new regenerant formulation. The new first regenerant solution is composed of a mixture of ferric chloride, a water-miscible organic solvent, hydrochloric acid, and water in which tetrachloroferrate anion is formed and used to displace the target anions on the resin. The second regenerant is composed of a dilute hydrochloric acid and is used to decompose tetrachloroferrate and elute ferric ions, thereby regenerating the resin. Alternative chemical displacement methods include: (1) displacement of target anions with fluoroborate followed by nitrate or salicylate and (2) displacement of target anions with salicylate followed by dilute hydrochloric acid. The methodology offers an improved regeneration efficiency, recovery, and waste minimization over the conventional displacement technique using sodium chloride (or a brine) or alkali metal hydroxide.
Abstract:
The invention relates to a device for regenerating an ion exchange cartridge. In household appliances with an electric heating element for heating water, such as irons, coffee makers, and electric water kettles, deposition of scale is prevented by using an ion exchange cartridge (16) comprising a resin (23) which binds alkaline earth metal ions such as Ca2+ and Mg2+, but also negative ions such as SO42− and CO32− ions. The device is a simple tool in which the cartridge can be inserted for regeneration. The device comprises a reservoir (2) with an outlet (10) to which an inlet (6) of the cartridge can be coupled. By filling the reservoir with a brine, for example 1 l of water with 10% by weight of NaCl, said brine will flow through the cartridge replacing the alkaline earth metal ions, carbonate ions, and sulfate ions in the resin with the alkali metal ions (Na+) and the chloride ions (Cl−) of the brine. The brine can be easily drained into a sink.
Abstract:
The disclosed invention is a fixed bed ion exchange system from removing arsenic from water. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system.
Abstract:
The present invention provides a controller for a water softener having an ion exchange resin capable of receiving hard water ions from hard water during a softening step and releasing the hard water ions during a regeneration step. The controller includes a processor programmed to cause termination of the softening step and initiate the regeneration step when both a first and a second condition are met. The first condition is met when the resin is saturated with hard water ions, and the second condition is met when current demand for soft water is at or below a prescribed flow rate.
Abstract:
An improved method for regenerating ion exchange resin in a treatment tank having a flow direction, which includes the steps of providing a supply of regenerant under pressure into the tank, and introducing the regenerant into the tank in an opposite flow direction to the treatment flow direction. In the preferred embodiment, the regenerant is a combination of CO2 which is mixed with water to form carbonic acid and citric acid. This mixture is then introduced into the treatment tank without storage.
Abstract:
Methods and apparatus for contacting solids and fluids are provided, where the fluids are allowed to traverse a downward path through a plurality of vertically arranged chambers in which said solids are located. The solids may be transferred upwardly through the chambers to assure optimal contact between the solids and the fluids. The transfer of the solids may be accomplished by fluidizing the solids and transporting them in a carrier fluid in a fluid flow loop. At the desired transfer location, the solids are prevented from completing passage through the fluid loop.
Abstract:
A well (12) outside of a brine tank (10) is provided which provides better accessibility to the brine refill valve (112) or other components within the well. Also, apertures (42-48) of differing elevations above the bottom of the brine tank can communicate between the brine tank and the well (12). Selected ones of the apertures can be plugged to select the quantity of water which can be removed and refilled in the brine tank.
Abstract:
A water softener and a method of operating the same are provided to allow for the efficient use of either NaCl or KCl as the regenerant salt. A user interface is provided to allow the user to indicate to the computer controlling the water softener whether NaCl or KCl is being used. The computer controller adjusts the fill time and brine time, depending on the type of regenerant salt used and on the temperature of the brine.
Abstract:
Regeneration of weakly basic anion exchange resins with a combination of an alkali metal carbonate and an alkali metal bicarbonate is disclosed. Preferably, the alkali metal is sodium. The combination can be naturally available sodium sesquicarbonate.
Abstract:
Described is a method for making brine to be used for regenerating water softening appliances. The brine is made in a reservoir having a float mechanism therein coupled to a seal that prevents the brine from dropping below a predetermined level in the reservoir. This creates a stock buffer of brine that always remain in the reservoir so that after adding a sufficient volume of water to regenerate a softening applicant, an effective concentration of brine is immediately available above the predetermined level for carrying out the regeneration. This allows for minimal wait time between subsequent regenerations of one or a plurality of water softening appliances. Preferably, an over-flow warning device cooperating with the reservoir water intake is also provided.