What is a porous medium?
porous medium is a substance that contains pores or gaps between a solid material that a liquid or gas can pass. Examples of naturally occurring porous media include sand, soil and some types of stone, such as pumice and sandstone. Spongs, ceramics and mesh foam are also produced for use as porous media. Possible applications of these materials in science, industry and everyday life are huge, although perhaps most often used as filters. Low -only materials are less permeable and usually have smaller pores, making it difficult to pass gas or liquid, while high -life materials have large pores and easily penetrate. Porosity is an important aspect of filtering, because if the particles must be removed by the porous medium, the leak must be small enough to capture them effectively. Geologists also consider the porosity of the surrounding stone and soil to perform observation of oil and natural gas storage. Natural gas trapped in a low -cornerstone is knownas “tight gas” and is more difficult to access than other reserves.
Resistance ranges from a low percentage of dense slate and sandstone up to about 50% in sand and up to 70% in clay. Materials created by man can be even more porous. For example, mesh foam, porous medium used in air conditioning filters and cosmetic applicators, has porosity up to 98%.
One of the most common applications of porous media in science and industry is filtration. In production plants, these materials can be used to filter gases or liquids either mechanically, by capturing particles or chemically, selective removal of certain compounds. A substance to be filtered by a tense porous medium and cleans when it passes pores in the material. Examples of industrial use of this method include water treatment and oil refinement.
porous media are also often used in aquaculture and domestic aquariums. CarbonRY, which consist of a porous activated carbon, are used in aquariums to absorb undesirable organic compounds and metals from water. The activated carbon is an example of chemical filtration, but possible mechanical filtration is also a possible possibility. In the latter system, the porous sponge mechanically filters out the particles and creates a cleaner environment for organisms in the tank.