1
Peter I Petrov, Ivan D Enchev, Kiril G Harisanov, Georgi N Korudanov, Georgi I Abrashev, Lyuben R Starev: Apparatus for the mechanical separation of cathode metal from a matrix. Institute po Tzvetna Metalurgia, Klein & Vibber, April 28, 1981: US04264405 (4 worldwide citation)

Apparatus for mechanically separating cathode metal such as zinc from a matrix during electroextraction of the metal. The matrix with layers of cathode metal on both sides thereof is supported on a frame and positioned by guides. Vacuum heads are advanced towards each other and brought into sealing ...


2
Ivan D Enchev, Lyuben R Starev, Elieser P Illel, Georgi N Korudanov: Method and apparatus for electric refining of lead. Institute Po Tzvetna Metalurgia, Klein & Vibber, October 30, 1990: US04966624 (1 worldwide citation)

A method for electric refining of lead with alternating current in which the basic stage of the process is preceded by two stages, a preparatory stage and an initial stage. The preparatory stage involves pretreatment of the electrode surfaces by means of alternating current of equal width and amplit ...