The difference between fireproof glass and tempered glass from the production process

Tempered glass: The original glass is cut according to the required  size-edging-opening-cleaning-tempering-inspection-storage.   Single piece of fire-resistant glass: The original glass is cut according to the required size-edging-opening-cleaning-ion replacement (the cleaned glass bubble is replaced by the cesium potassium ion solution at a specific temperature to replace the calcium on the surface of the cleaned glass Ion and sodium ion)-cleaning-tempering (tempered wind pressure is 3 times that of ordinary tempered glass)-quality inspection-packaging-storage.   Difference summary:   1. Tempered glass is only a physical change, and fire-resistant glass is already a chemical change.   2. The toughened wind pressure is increased, and the impact resistance of the fireproof glass is better.

2020-12-23

3.U.S. scientists develop new type of color-changing glass that can be turned into solar cells after heating

According to foreign media New Atlas, windows are a good daylighting tool, but in summer, this also brings unnecessary heat, causing many people to have to turn on air conditioning. Now, researchers have developed windows that can automatically change color when the sun heats up to keep buildings cool - most importantly, they are also solar panels. The color-changing glass has been around for a long time, and the most common one is as a transition lens of glasses, which automatically adjusts color under strong light. Recent developments have made it electronic, which can be switched on demand and enlarged to the size of a window. At the same time, the efficiency of transparent (or translucent) solar cells is getting higher and higher, and they can even be installed on windows.   In this new study, researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) combined these two technologies into a single window. What they call "thermochromic photovoltaic" technology can switch colors when heated by sunlight to block glare and reduce the need for cooling. When it does so, it also starts to collect energy from this light.   This kind of window is made of a thin film of perovskite-a new type of solar cell material-sandwiched between two pieces of glass, and solvent vapor is injected into the gap. When the humidity is low, the perovskite film remains transparent, allowing the windows to transmit light normally. But at a certain temperature, steam will rearrange the perovskite crystals, first into chains, then flakes, and then cubes. Each new shape will change the color and block the light to varying degrees. It is hoped that the room will be cooled by a few degrees in the process.   When the glass temperature reaches 35°C to 46°C, the window can switch between several different colors, from transparent to yellow, orange, red and brown, it takes about 7 seconds. This is a considerable improvement over the early prototype developed by the NREL team. When the temperature reaches 65.5°C to 79.4°C, it can only switch between transparent and a reddish brown, and it takes 3 minutes to complete.   Ideally, “thermochromic photovoltaic” windows can help reduce the need for air conditioning, because air conditioning is a huge energy consumer in hot times and climates, and even a little extra electricity can be raised to help it operate. The team stated that a prototype window using the new technology can be developed within a year.

2020-12-23

2.Black technology! Baotou Research Institute develops thermal insulation rare earth glass coating that can save energy by 25% to 40%

As we all know, the heat energy on the earth's surface mainly comes from sunlight, and the spectrum of sunlight is mainly concentrated in the range of 200-2500nm, of which: the range of 200-400nm is ultraviolet, its energy accounts for about 5% of the total energy of sunlight, and the range of 400-720nm The inner part is visible light, whose energy accounts for about 45% of the total energy of sunlight, and the range of 720-2500nm is infrared, whose energy accounts for half of the total energy of sunlight.   Infrared rays are invisible to the human eye. Therefore, how to effectively block the infrared rays and improve the heat insulation performance of glass without affecting the transmission of visible light is one of the most difficult points in domestic and foreign technology research and development. At present, the research and development of high-quality, high-permeability heat-insulating film is mainly concentrated in developed countries such as the United States and Japan. "Although there are many methods for blocking sunlight in the prior art, each has many problems." Lu Fei said.   Lu Fei explained its shortcomings to reporters by taking Low-E glass (Low-E), the most commonly used building insulation glass, as an example. This type of glass achieves the thermal insulation effect by coating the surface of ordinary glass. However, after extensive use of this type of glass on the exterior wall of the building, although it has good heat preservation and heat insulation properties for the building itself, it will reflect a lot of sunlight and cause a lot of light pollution problems.   People working in a light-polluted environment for a long time can cause vision loss, dizziness, insomnia, heart palpitations, decreased appetite, and depression, which seriously affect people's physical and mental health. In addition, Low-E glass cannot obtain heat insulation on the surface of the glass through post-painting and other methods. In addition, due to the oxidation of the metal layer, the life of the surface layer is much lower than that of the glass itself, which makes Low-E glass unable to be used as It is used to upgrade the existing architectural glass.   In addition, colored glass absorbs visible light while absorbing heat. It will greatly sacrifice visible light transmittance while achieving heat insulation, and present obvious colors, which greatly limits its need for high visible light such as car front windshields. Through the application of the scene.   "At present, cesium tungsten bronze, a widely used infrared absorbing material in commercial applications, has a good infrared absorbing effect. However, it will exhibit photochromic phenomenon under ultraviolet radiation, and will interact with water and oxygen under heating. An irreversible oxidation reaction occurs, generating tungsten trioxide and losing its infrared absorption properties." Yin Jian said.   A new thermal insulation coating comes out   From the above analysis, it can be seen that the thermal insulation principle of traditional Low-E glass and glass products is to achieve the thermal insulation effect by coating the surface of ordinary glass. After coating, Low-E glass can reflect far infrared rays with wavelengths above 2500nm. , But it can also cause pollution. Absorbing photons may be a better choice.   "We are also inspired by the phenomenon of localized surface plasmon resonance (LSPR), because the surface electrons of gold nanobelts with a certain aspect ratio can resonate with incident photons of a certain frequency, and strongly absorb the incident photons before passing through Adjusting the particle size and morphology of the material can achieve selective absorption of infrared photons, which can be made into infrared absorbing materials." Lu Fei said.   According to Lu Fei, the coating they made is based on rare earth compounds. On the one hand, because boron atoms have strong electronegativity, they can form a strong force with rare earth elements, making the rare earth nano thermal insulation materials formed. Good acid and alkali resistance; on the other hand, in the formed rare earth nano boride material, the outer layer electrons of the rare earth element itself provide a large number of free electrons. When the photons of incident light are excited, the free electrons resonate with the incident photons. Thus, the macroscopic performance is the heat absorption capacity.   In addition, by adjusting the type and doping amount of rare earth elements, the wavelength range where incident photons resonate can be further controlled. Using this method, the R&D team successfully developed a high-performance rare earth nanocomposite thermal insulation material with good weather resistance, which solved the problem of insufficient environmental stability of existing materials and the inability to absorb infrared spectra.   "The coating we developed has a red and ultraviolet barrier greater than 90%, a vi

2020-12-23

German scientists have developed a more environmentally friendly fireproof glass production process produces less waste

Although fire windows already exist, they contain a carcinogenic gel, and their production generates a lot of waste. However, a new technology that works in the same basic way is said to be safer and less wasteful. Normally, this kind of window consists of two pieces of glass with a layer of transparent acrylamide-based hydrogel in between.   Once the pane facing the flame is heated to the point of breaking, the gel will be exposed to the flame. When the water in the gel continues to boil, the temperature of the bottom pane will decrease through the evaporative cooling effect. In addition, the gel forms a thick layer of insulating salt on the second layer of glass, further protecting it.   Scientists at the Fraunhofer Institute for Environment, Safety and Energy Technology in Germany, in order to find a more harmless alternative to the toxic acrylamide hydrogel, they conducted experiments with a variety of substances. After about 60 failed attempts, they finally found an undisclosed "basic ingredient" that met the requirements.   It is not carcinogenic and has no other dangers, but it can still keep windows intact when exposed to temperatures exceeding 1000 oC for up to 2 hours. In addition, on a production line that is producing indoor fire doors made of such glass, only 20 kilograms of waste are generated every day. In contrast, according to Fraunhofer’s data, the production of traditional fire windows generates 150 to 160 kilograms of waste per day.   At present, this kind of glass is used in the reconstruction of the Frankfurt Global Tower and the construction of the big tower.

2020-12-23