Method of measuring oxygen activities in slag

摘要

PCT No. PCT/JP90/01324 Sec. 371 Date Jun. 17, 1991 Sec. 102(e) Date Jun. 17, 1991 PCT Filed Oct. 15, 1990 PCT Pub. No. WO91/06003 PCT Pub. Date May 2, 1991.A method and apparatus for measuring the oxygen activity of the slag in molten iron or molten steel with high accuracy. A conventional measuring method in which an oxygen concentration cell produced by winding a platinum contact electrode around the outer surface of a solid electrolyte of one end closed tube type is disposed directly in the molten slag involves a fear of producing an error in measurement due to the difficulty in positioning in the fluid slag and the defective contact with the contact electrode caused by the densification by the heat of the slag. In the present invention, the oxygen activity in the slag is not directly measured but a specific metal between which and the slag an oxygen equilibrium is established when it comes into contact with the slag is charged in a container together with the slag. The oxygen activity of the specific metal is measured so as to indirectly measure the oxygen activity in the slag. The problems caused by the defective contact between the solid electrolyte and the contact electrolyte are thus solved, thereby enabling measurement of the oxygen activity in the slag with high accuracy.