Mineral wool

Mineral wool is any fibrous material formed by spinning or drawing molten mineral or rock materials such as slag and ceramics. Mineral wool is any fibrous material formed by spinning or drawing molten mineral or rock materials such as slag and ceramics. Applications of mineral wool include thermal insulation (as both structural insulation and pipe insulation, though it is not as fire-resistant as high-temperature insulation wool), filtration, soundproofing, and hydroponic growth medium. Mineral wool is also known as mineral fiber, mineral cotton, mineral fibre, man-made mineral fibre (MMMF), and man-made vitreous fiber (MMVF). Specific mineral wool products are stone wool and slag wool. Europe also includes glass wool which, together with ceramic fiber, are completely man-made fibers. Slag wool was first made in 1840 in Wales by Edward Parry, 'but no effort appears to have been made to confine the wool after production; consequently it floated about the works with the slightest breeze, and became so injurious to the men that the process had to be abandoned'. A method of making mineral wool was patented in the United States in 1870 by John Player and first produced commercially in 1871 at Georgsmarienhütte in Osnabrück Germany. The process involved blowing a strong stream of air across a falling flow of liquid iron slag which was similar to the natural occurrence of fine strands of volcanic slag from Kilauea called Pele's hair created by strong winds blowing apart the slag during an eruption. American chemical engineer Charles Corydon Hall in 1897 developed a technology to convert molten limestone into fibers and initiated the rock wool insulation industry in America. According to a mineral wool manufacturer, the first mineral wool intended for high-temperature applications was invented in the United States in 1942, but was not commercially viable until approximately 1953. More forms of mineral wool become available in the 1970s and 1980s. High-temperature mineral wool is a type of mineral wool created for use as high-temperature insulation and generally defined as being resistant to temperatures above 1,000 °C. This type of insulation is usually used in industrial furnaces and foundries. Because high-temperature mineral wool is costly to produce and has limited availability, it is almost exclusively used in high-temperature industrial applications and processes. Classification temperature is the temperature at which a certain amount of linear shrinkage (usually two to four percent) is not exceeded after a 24‑hour heat treatment in an electrically heated laboratory oven in a neutral atmosphere. Depending on the type of product, the value may not exceed two percent for boards and shaped products and four percent for mats and papers.