Abstract
LIQUID GAS CO. LTD liquefy and separate air into nitrogen, oxygen and argon with our power-saving and highly efficient plant, using liquefied natural gas （LNG : -162℃） which OSAKA GAS CO. LTD then receives as an ingredient of natural gas. Using liquid nitrogen (LN2 : -196℃) as the refrigerant, LIQUID GAS CO. LTD has successfully developed the powder processing service of cryogenic-grinding. In this process, the raw materials are cooled and/or frozen by LN2 to below brittle temperatures, where materials that are very difficult to grind at room temperature can be easily ground. Heat generation and oxidization are also restricted, so that the fundamental characteristics can be maintained. In addition, inactive LN2 enables the prevention of dust explosion.
Cryogenic-grinding reduces environmental loads in relation to the effective of LNG cold energy, and is a practical form of environmental engineering applicable to recycling and waste reduction. The purpose of this paper is to provide an outline of cryogenic-grinding, and provide specific examples of the potential applications.
