Bisbee daily review., 1905-09-06

] As the result of extended expert
 ments the shannon Copper Company | at Clifton, Ariz., is equipping the jigs
 of its 60O-tOn concentrating plant with ' an apparatus for protecting the jig ! screens from the destructive action of the acid waters used in concentration. ] The concentrating ores in the Clifton ! MOrenci district are mainly sulphides
 and sulphates of copper, and the mill ing water carries such a large per icentage of sulphuric acid and copper sulphate that it is ruinous to jig 1 screens. whether they be of copper, | brass, steel or iron. The average stee. 1 screen lasts but two or three days while the most expensive copper and l brass screens require renewal at least every thirty days. The wear of the 1 screens is due partly to the corrosive action of the acids or metallic salts contained in the water
 The device experimented with and now being fitted to all the jigs is the | invention of John W. Bennie, the com pany's general manager, and Henry s. ! Anderson, an electrical engineer of ] Springfield. Mass. The experiments
 were carried on under the personal Supervision of Mir Bennie.
 l The apparatus consists of an cleo trode of graphite suspended below the metallic screen and connected to one terminal of an external source Of continuous electric current. while con. nection is made with the screen anc
 the other terminal whereby the screen | becomes the cathode or electro-nega- tive element, the electrode being the
 al raG=ffiNn n1nfro nraf With this arrangement the screen is protected against corTosion, hydrogen being set free at it's surface and the
 metallic salts in the solution being de composed so that the copper metal is electrolytically deposited upon the screen. The copper deposit is formed
 in opposition to the abrasive action of the ore, and to the extent of the de
 posit the abrasive action on the orig. inal screen is reduced, wLAe the de
 posit on parts not subject to abrasive
 action builds up and strengthens the screen. In experimentation the device
 demonstrated the practicability of us
 ing steel wire or punched steel screens
 in place Of the more expensive copper
 and brass screens now in use Hard
 steel screens used for a period Of
 sixty days showed no corroslOn what
 ever and the wear from abrasion was
 simply a question of the hardness of
 the steel or iron used and this wear
 was in part cOmr ensated by the cleo
 trolytic disposition of the copper from
 the sulphate salts in soiution in the concentrating water. Steel screens protected in this way were shown
 to last several times as long as the copper screen, thereby efecting a large saving in the cost of material
 The electrical energy required was
 from two to five volts for each apDa- ratus, and but a few horsepower will be required for all the jigs of the com psny's 600-ton plant.
 IL is further stated that experiments showed it to be immaterial how cor rosiye the water might be or become in use. insofar as the elimination of Icorrcsion is concerned, so long as theI low voltage generator is doing it's
 work
 The principal features of this mech
 anism appear to be its simplicity and positive action, and there seems toI be no reason why it cannot be used to advantage in other localities where acid waters play havoc with jig screens. The item of expense as re- gards the cost of steel and copper or
 brass screens is certainly an impor- tant one, while the loss of time ne
 cessitated in the frequent replace
 ments of screens is another consider ation.
 TO PIPE WATER 20 MILES.
 Water is to be piped 20 miles from the headwaters of the Sacramento
 river to Brice, New Mexico, by the Southwest Smelling & Refining com pany. The same company will gene
 rate electric power, using atomized
 crude petroleum in ordinary gas en- zines for the purpose.