| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce platinum foreign matter contaminating a glass by keeping an oxygen concentration in a combustion space in a glass-melting furnace for melting the glass by burning a fuel with oxygen, at a specified value. SOLUTION: The oxygen concentration in a combustion space A in a glass- melting furnace 1 of an oxygen combustion type where a fuel is burned by using the oxygen is kept at >=5% and <=50%. The regulation of the oxygen concentration in the combustion space A is carried out by measuring the oxygen concentration in a gas duct for exhausting the waste gas generated by the combustion to the exterior, regulating the feed of the oxygen to an oxygen combustion burner 2 of a combustion device according to the result to keep the oxygen concentration in the combustion space A at the specific value. As a result, platinum contaminating the glass in a production step is oxidized, and dissolved in the glass as an oxidized ion state, and thereby the platinum foreign matter can be reduced and the yield of the product is improved.</p> |
