Abstract:
A filter apparatus for water purification is provided. A compact housing has a disk filter including concentric chambers connected in series with divided water flow in opposite directions in each chamber with one water tank input and one purified water output.
Abstract:
System for softening and dealkalizing water by feeding said water to both chambers of an electrolytic cell which chambers are separated by a cation exchange membrane, applying DC voltage to the electrodes of the cell, at intervals, reversing the applied polarities, and drawing soft dealkalized water from the anodic compartments.
Abstract:
A system for converting sodium sulfate ore into chemicals of which H.sub.2 SO.sub.4 and Na.sub.2 CO.sub.3 are examples, utilizing a membrane process, the basic electrodialysis cell of which is located, usually as a series of such cells, between cathode and anode compartments. Each cell constitutes a pair of cation permselective membranes between which a bi-polar membrane is disposed in spaced relationship thereto with the cation permselective face thereof confronting the cation permselective membrane and the anion permselective face thereof facing the other cation permselective membrane. The cation permselective membranes of adjacent cells are common to such adjacent cells. All of the cation permselective faces of the bi-polar membranes face the cathode electrode and all of the anion permselective faces of the bi-polar membranes face the anode electrode. Each cell includes a base zone and an acid zone. Each acid zone is defined by a cation permselective membrane and the confronting cation permselective face of the bi-polar membrane and each base zone is defined by a cation permselective membrane and the confronting anion permselective face of the same bi-polar membrane. The acid zone is fed by a water solution of a sodium salt, for example Na.sub.2 SO.sub.4 and Na.sub.2 S and the base zone is fed by a saturated water solution of NaHCO.sub.3 or by a water solution of a mixture of NaHCO.sub.3 and Na.sub.2 CO.sub.3 or by a mixture of a water solution of Na.sub.2 CO.sub.3 and CO.sub.2 which reacts with the Na.sub.2 CO.sub.3 to form NaHCO.sub.3. The feeding of these composite solutions to the different zones results in increased current efficiencies by removing free H.sup.+ ions from the acid zone and free OH.sup.- ions from the base zone. The cathode and anode electrodes are disposed in respective compartments through which water solutions of NaOH circulate. The cell is part of a plant in which other treatments are performed.