What does a tasty cup of tea and a metal recovery plant have in common? Well in practice nothing, but in principle much more than one can expect. Fortunately, it’s not about the ingredients. Instead, the comparison has to do with the process through which one is able to extract a substance from a solid material that has come into contact with a liquid. The process is called leaching.
Indeed, as every morning billions of people unwittingly use this extraction technique to enjoy the organoleptic properties of tea and coffee, at the same time many industries greatly benefit from the vast number of leaching applications. For example, leaching is widely used in the biological and food processing industries for the separation of sugar from sugar beets with hot water, or for the extraction of oil from peanuts, soybeans and sunflower seeds. Likewise, many pharmaceutical products are obtained by leaching plant roots, leaves and stems.