GB190500149A - Improvements in Apparatus for the Separation of Liquids from Solids, more especially intended for use in the Treatment of Metalliferous Ores. - Google Patents

Abstract

149. Lomas, W. H. Jan. 3. Travelling-band filters, especially applicable for use in connection with the cyanide process of gold extraction, consist of an endless porous belt, which passes round two revolving perforated drums, the liquid being drawn off through one drum and the solids discharged by means of the other drum. A frame A, suppcrted at one end for purposes of adjustment by means of hangers A<3>, is provided underneath with bearings c, in which is journaled a drum D having hollow bearings d<5> through which passes a stationary pipe E closed at one end by a cap. The drum D is formed with grooves d<3> communicating by means of holes d' with the interior. Brackets H fixed to the frame carry bearings h in which is mounted a drum or pipe G formed with grooves g communicating by means of holes g<1> with the interior. A stationary pipe J, closed at one end by means of a cap j and formed with a longitudinal slot j<1>, passes through the drum G and is retained in position by means of collars J<2> secured on the drum pipe J. A porous belt L of canvas or the like or of woven wire of suitable mesh passes round the drums G, D and is caused to embrace a large part of the circumference of the drum D by means of guide-rollers such as k<1>, k<2>, the bearings k<4> of the roller k<1> being attached to screwed rods k<5> which serve to tighten the belt. The apparatus is driven from any of the pulleys N, O, K, F, the pulley K being secured on the drum G and the pulley F on the drum D. A curved plate R is attached to the stationary pipe E by means of arms, and is of such size as to cover that portion of the interior of the drum D which is not covered by the belt L. Along its two parallel edges the plate R is formed with slots, in which are located bars which abut the inner side of the drum D and are kept in contact therewith by means of springs. The curved edges of the plate Rare also formed with slots in which bars pressed against the drum are placed. The plate R may be adjusted in position by means of a. lever T which works over a quadrant t. A number of pipes V are provided for the purpose of exhausting air from the drum D, and the pipe E is provided with a depending branch v for drawing off water. A lever W fixed to the closed end of the pipe J works over a quadrant wand serves to adjust the slot j<1> in any desired position in relation to the perforated drum G. In operation, the mixture of liquid and solid is charged into a trough C so that the pipe E is below the level of liquid and motion is imparted to the belt L. A pump or the like is connected to the pipe E and the air withdrawn from the drum D. Liquid is forced through the belt L, and is extracted by means of the branch v and the pipe E. The traveller belt, which moves at the top from right to left, carries the solids over the roller k<1> and then underneath the drum G. The pipe J is in communication with a supply of air or other fluid or of air and water, and during the passage of a belt L over the drum G the solids are discharged from the belt. In a modification of the drum D, an inner pipe having branches is arranged to draw off the air and is not in direct communication with the water draw-off pipe.