Sepor now manufacturers two sizes of Laboratory Leach Columns for the leach testing of ores with the addition of the new 10” column. The Leach Column is constructed of PVC and Stainless Steel. It has a stainless steel solution tank with a sample point, valves and variable speed pump to easily regulate the solution flow. All hose, piping, valves and column are constructed of PVC. The leach columns are designed to be easy to use and functional for testing the leachability of ores for possible heap leach recovery of metals. Sepor’s 6” diameter column is suitable for leach testing on ore sized ½” or finer, while the larger 10” diameter column is suitable for ore sized 2 inches and finer. Both columns are equipped with stainless steel handles to assist in removing the columns.
Laboratory leach testing procedures include the studies of dissolving metal ions with an acid, base, cyanide or other chemicals. The leach column simulates the effects of heap leaching of an ore in a controlled lab environment making data collection simple. In order to eliminate any effect in the lab leach columns the maximum size for each diameter of column should be adhered to. The 6” diameter by 72” in height and the 10” by 79” in height and are both constructed of PVC and the solution reservoir is constructed of Stainless steel. A 10 Mesh stainless steel screen covers the drain plate to prevent fine grained material from plugging the recirculation pump. The stainless steel drainage plate also serves to support the column of rocks.
A peristaltic pump with PVC tubing is used to recirculate the leach solution. Samples may be easily collected from the leach solution to monitor temperature, concentration, density, extraction of precious metals as well as undesirable elements.
The ore’s placed into the column should be screened prior to inserting in order to determine particle size distribution for later use comparing recovery to particle size. The time required to obtain maximum practical recovery is also an important element to monitor for use in determining leach rates. Any additives, such as lime to maintain a higher pH should also be noted. The consumption of the leach solution should be recorded for each test in order to determine the projected leach rates.