1. Energy saving and emission reduction
In order to solve the global greenhouse effect, in the Kyoto Protocol adopted in 1997, the annual greenhouse gas emissions from 2008 to 2012 were reduced by 5.2% compared with 1990.
2. Oxygen combustion
Since the 1990s, oxy-fuel combustion technology has been widely used in glass fiber, container, optical and electronic glass furnaces. Oxygen combustion can effectively reduce the emission of pollutants such as NO and dust, save energy consumption, reduce or avoid the cost of environmental protection and the construction of regenerators, and can also improve the output and quality of glass products.
After adopting oxy-fuel combustion technology, the combustion-supporting gas is greatly reduced; however, the concentration of water vapor harmful to SiO2 is increased by 2 times, which makes many refractory materials containing SiO2 in the upper part of the kiln suffer serious erosion. For example, the life span of silica bricks has been drastically reduced from 10 years to 2 years, restricting the development of oxy-fuel combustion technology.
3. New melting system
The new kiln technology also includes decompression clarification and immersion combustion. Decompression clarification is the process of sucking the glass liquid into a vacuum chamber and going through the processes of degassing, clarification, homogenization and cooling to make glass. The immersion combustion is to place the burner at the bottom of the kiln and blow gas and oxygen into the glass to burn in the liquid phase. The energy generated by the combustion can be used to enhance the heat transfer between the kiln gas and the glass, accelerate the physical and chemical changes, and reduce Energy consumption, increase production, improve quality.
4. Alternative fuel
In order to reduce production costs, some glass companies in my country have conducted experiments to use petroleum coke instead of heavy oil to make glass, and have achieved initial success.
Petroleum coke can be used as an alternative fuel. Its calorific value is about 30-36 MJ·kg, ash content is 0.1% -0.3%, volatile matter is about 10%, and carbon content is about 90%. At present, the price of fuel-grade petroleum coke is only 1/4-1/3 of that of heavy oil. In recent years, domestic petroleum coke production has grown rapidly. In 2005, the total output of petroleum coke was 640,000 tons. Overall, 75% of petroleum coke can be used as a fuel-grade by-product. If petroleum coke is used to completely replace heavy oil, the fuel cost of each 900t·d-1 glass melting furnace can be reduced by about 60%, and the annual economic benefit will increase by more than 65 million yuan. Even if you count the cost of pollution, you can still save 30% of the cost. Tests have shown that the use of petroleum coke can produce qualified glass, but it will affect the service life of refractory materials in the regenerator.