According to the historical development stage, glass can be divided into ancient glass, traditional glass, new glass and late glass.
(1) In history, ancient glass usually refers to the era of slavery. In Chinese history, ancient glass also includes feudal society. Therefore, ancient glass generally refers to the glass made in the Qing Dynasty. Although it is being imitated today, it can only be called antique glass, which is actually a fake of ancient glass.
(2) Traditional glass is a kind of glass materials and products, such as flat glass, bottle glass, utensil glass, art glass and decorative glass, which are produced by melt supercooling method with natural minerals and rocks as the main raw materials.
(3) New glass, also known as new functional glass and special functional glass, is a kind of glass that is obviously different from traditional glass in composition, raw material preparation, processing, performance and application, and has specific functions such as light, electricity, magnetism, heat, chemistry and biochemistry. It is a high-tech intensive material with many varieties, small production scale and fast upgrading, Such as optical storage glass, three-dimensional waveguide glass, spectral hole burning glass and so on.
(4) It is difficult to give a precise definition of future glass. It should be the glass that may be developed in the future according to the direction of scientific development or theoretical prediction.
No matter ancient glass, traditional glass, new glass or future glass, all have their commonness and individuality. They are all amorphous solids with glass transition temperature characteristics. However, personality changes with time, that is, there are differences in connotation and extension in different periods: for example, new glass in the 20th century will become traditional glass in the 21st century; Another example is that glass ceramics was a new kind of glass in the 1950s and 1960s, but now it has become a mass-produced commodity and building material; At present, photonic glass is a new functional material for research and trial production. In a few years, it may be a widely used traditional glass. From the perspective of glass development, it is closely related to the political and economic situation at that time. Only social stability and economic development can glass develop. After the founding of new China, especially since the reform and opening up, China’s production capacity and technical level of flat glass, daily glass, glass fiber and optical fiber have been at the forefront of the world.
The development of glass is also closely related to the needs of society, which will promote the development of glass. Glass has always been mainly used as containers, and glass containers account for a considerable part of the glass output. However, in old China, the manufacturing technology of ceramic ware was relatively developed, the quality was better, and the use was convenient. It was rarely necessary to develop unfamiliar glass containers, so that the glass remained in imitation jewelry and art, thus affecting the overall development of glass; However, in the west, people are keen on transparent glassware, wine sets and other containers, which promotes the development of glass containers. At the same time, in the period of using glass to make optical instruments and chemical instruments in the west to promote the development of experimental science, China’s glass manufacturing is in the stage of “jade like” and it is difficult to enter the palace of science.
With the progress of science and technology, the demand for the quantity and variety of glass continues to increase, and the quality, reliability and cost of glass are also increasingly valued. The demand for energy, biological and environmental materials for glass is becoming more and more urgent. Glass is required to have multiple functions, rely less on resources and energy, and reduce environmental pollution and damage.
According to the above principles, the development of glass must follow the law of scientific development concept, and green development and low-carbon economy are always the development direction of glass. Although the requirements of green development are different in different historical stages, the general trend is the same. Before the industrial revolution, wood was used as fuel in glass production. Forests were cut down and the environment was destroyed; In the 17th century, Britain banned the use of wood, so coal-fired crucible kilns were used. In the 19th century, regenerator tank kiln was introduced; Electric melting furnace was developed in the 20th century; In the 21st century, there is a trend towards non-traditional melting, that is, instead of using traditional furnaces and crucibles, modular melting, submerged combustion melting, vacuum clarification and high-energy plasma melting are used. Among them, modular melting, vacuum clarification and plasma melting have been tested in production.
Modular melting is carried out on the basis of preheating batch process in front of kiln in the 20th century, which can save 6.5% of fuel. In 2004, Owens Illinois company carried out a production test. The energy consumption of traditional melting method was 7.5mj/kga, while that of module melting method was 5mu / KGA, saving 33.3%.
As for vacuum clarification, it has been produced in 20 t / D medium-sized tank kiln, which can reduce the energy consumption of melting and clarification by about 30%. On the basis of vacuum clarification, next generation melting system (NGMS) has been established.
In 1994, the United Kingdom began to use plasma for glass melting test. In 2003, the United States Department of energy and glass industry association carried out a high-intensity plasma melting E glass, glass fiber small tank furnace test, saving more than 40% energy. Japan’s new energy industry technology development agency also organized Asahi nitko and Tokyo University of technology to jointly establish a 1 T / D experimental kiln. The glass batch is melted in flight by radio frequency induction plasma heating. The melting time is only 2 ~ 3 h, and the comprehensive energy consumption of finished glass is 5.75 MJ / kg.
In 2008, Xunzi carried out 100t soda lime glass expansion test, the melting time was shortened to 1 / 10 of the original, energy consumption was reduced by 50%, Co, no, pollutant emissions were reduced by 50%. Japan’s new energy industry (NEDO) technology comprehensive development agency plans to use 1t soda lime glass test kiln for batching, in-flight melting combined with vacuum clarification process, and plans to reduce the melting energy consumption to 3767kj / kg glass in 2012.
Post time: Jun-22-2021