By Charles Kubach, Mine-Engineer.Com Sampling solids in a plant or mill is similar to sampling slurries. The sample should be taken from a moving stream, making a complete cross sectional cut of the stream, and using enough increments to be statistically accurate. Generally, this means sampling at a conveyor discharge point, or a chute discharge point. Multi stage sampling is usually employed, to take a large enough initial sample to be representative of the whole, then splitting the first sample in stages, to obtain a sample size the laboratory can handle. A very accurate method of taking the primary sample, is using a Linear Cross Stream Sampler, placed at a transfer point, such as conveyor or chute. Other methods include a splitter tower (production version of lab riffle splitter. I made one of these 70 feet tall once, and used it with flop gates installed in chutes at a barge loading facility, to sample 10,000 ton lots, with a final sample of around 6 cubic feet (55 gallon drum). A photo of a small splitter tower is below. This was made for a limestone company, to split their secondary sample for the lab. It used a hammermill to reduce large particles to 10 mesh and finer, to increase the statistical accuracy of the split. It was fed by using a overhead hoist and dumping a 55 gallon drum of -1 inch sampled limestone through it.  For information of the equipment used in solids sampling, click in the following buttons on the side menu: Riffle Rotary Sampling Vezin Cross Stream Custom
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