Abstract: A mercury retorting apparatus, a retorting system, and a method for continuous removal of mercury from dry, semi-granular, and sludge materials contaminated with mercury without shutting down the system for removal of accumulated liquid mercury, water, and dust particles. The retorting apparatus comprises a powered screw feed assembly having a feed tube with a closely fitting feed screw therein. The screw feed assembly feeds the material from the lower portion of a hopper configured to contain a quantity thereof into a rotatably powered retorting tube in which a vacuum is drawn. The material forms a seal within the powered screw feed assembly against vacuum loss in the retorting tube during operation thereof. A first rotatable seal between the feed tube and retorting tube prevents vacuum loss therebetween. An elongate electric kiln encloses the mid-portion of the retorting tube.

Abstract: An electrowinning cell and a cathode for use therein for removal of gold or other precious metals from a solution thereof in a suitable electrolyte. The cathode comprises a perforated steel plate wrapped in layers of woven wire mesh secured thereto. The cathode design is such that the cathode may be cleared of deposited gold sludge by use of an ordinary garden hose spray nozzle without its removal from the cell, making the electrowinning process faster and more economical.