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As we all know, in the process of glass melting, oxides, carbonates, nitrates, etc. put into the glass materials form silicates and a large number of gases in the process of high-temperature chemical reaction: CO, CO2, SO2, NO2, O2, H2O and other gases.

The weight of this part of gas accounts for about 18% ~ 20% of the weight of the glass material. In this large amount of gas emissions, some of the gas will stay in the glass liquid due to its small volume and proportion. When the temperature of the glass liquid drops, the viscosity of the glass liquid increases, and the gas is more difficult to overflow the liquid surface, and the small bubbles formed in the glass need to be defoaming with the glass clarifier to achieve the clarification.