Energy Saving Methods For Float Glass

The glass industry is a high energy consuming industry, and glass furnaces are the most energy-efficient equipment in glass production lines. Fuel costs account for approximately 35% to 50% of glass costs. Most of the float glass furnaces designed by China can achieve a glass liquid unit consumption of 6500kJ/kg to 7500kJ/kg, while foreign large float glass enterprises only have 5800kJ/kg of glass liquid. There is a certain gap between us and the international advanced level.
The thermal efficiency of glass furnaces in developed countries generally ranges from 30% to 40%, while in China, the average thermal efficiency of glass furnaces is only 25% to 35%. The unreasonable design and insulation measures of the furnace structure, as well as the low quality of the refractory materials used, are one of the important reasons for this gap. Secondly, the outdated operation technology and inadequate management of domestic float glass process are also the reasons for high energy consumption, poor melting quality, and short furnace life. Up to now, China has more than 140 float glass production lines, with a rapid increase in glass production capacity and gradually intensifying market competition. As the main fuel for glass, the price of heavy oil continues to rise, accounting for an increasing proportion of glass costs. Therefore, reducing glass energy consumption is of great significance for reducing production costs, improving market competitiveness of enterprises, reducing environmental pollution, and alleviating energy shortages.
Energy conservation in glass enterprises is a long-term task, and domestic and foreign technicians are actively conducting research, such as optimizing furnace structure design, oxygen rich combustion, full oxygen combustion electric melting, heavy oil emulsification technology, etc. At present, many enterprises have started implementing energy-saving measures in the production process and exploring energy-saving measures in glass production process control and other aspects.
The moisture, temperature, and fuel consumption of the batch are well-known, and the state of moisture in the batch is closely related to the temperature of the batch. When the temperature of the batch is greater than 35 ℃, the vast majority of water adheres to the surface of refractory sand particles in a free state, which can enhance the melting effect by adhering more pure alkali. When the temperature of the batch is less than 35 ℃, the moisture in the batch will form Na2CO3 · 10H2O or Na2CO3 · 7H2O with soda ash, and form Na2SO4 · 10H2O crystalline water compound with mirabilite, causing the surface of the sand particles to lose moisture and appear dry, weakening the melting effect.
In northern regions, due to low temperatures in winter, the temperature of the mix is generally lower than 35 ℃, and in some regions it is even around 20 ℃. In order to maintain a moist appearance of the batch, the method of increasing the moisture content of the batch is usually adopted. Although it has a certain effect, it can also bring many drawbacks, such as increased agglomeration on the silo wall and increased fuel consumption. Someone calculated that the amount of oil required to enter the kiln for water is 0.085kg of oil/kg of water.