Foundry by-products are generated by the metal casting industry. The most common foundry by-product, foundry sand, is a discarded material resulting from metal-casting industries, where it’s used to create molds and cores. Nearly all foundry sand from ferrous foundries is classified as non-hazardous waste, which makes it a safe and sustainable material for beneficial reuse applications, most commonly as geotechnical fill. Other foundry by-products include baghouse dust, casting sand, and slag.
How is it Generated?
Aluminum, iron, and steel (ferrous) foundries use graded and washed sand, bentonite clay, sea coal (a form of carbon), and a grain to produce a molding sand for pouring castings. Cores made from sand and resin are placed in some molds requiring an internal passageway. Some foundries use resin sand to produce molds and cores. After the mold is poured and cooled the molding sand and cores are separated from the castings and the molding sand is recycled to make new molds. Over time some of the molding sand is removed from the sand system and becomes spent molding sand which get recycled.