On the energy-saving aspects of polysilicon
Thread Content
Regarding the energy-saving aspects of polysilicon, it is well known that the improved Siemens process for producing polysilicon involves high power consumption, significant pollution, and a complex manufacturing process. This technology is not yet fully developed in China, and achieving electronic-grade polysilicon is even more difficult. The new silane method brings hope to the polysilicon industry in China; a company in Hebei has already started pilot production of polysilicon through the hydrogenation of silicon tetrafluoride, and it is said that this method offers excellent energy-saving benefits. “The recovered hydrogen will be used in the production of sodium aluminum hydride, resulting in annual savings of 13.36 million yuan” ； 37,600 tons of liquid nitrogen were recovered through vaporization, saving over 10 million yuan per year ； The steam generated by the waste heat in the CVD reactor can reach 1,668 cubic meters per hour, and recycling it on a yearly basis can save 38.07 million yuan in costs. Calculated in this way, its cost is only 200,000 yuan per ton, which is one-third lower than that of Xifa. I was thinking that in the improved Siemens process, there is a lot of waste heat, and a large amount of nitrogen is used, but relatively little of it is utilized for recovery. If it can be recycled, it will of course help to save a lot of costs, but it will definitely require additional equipment and more investment. Is there a way to achieve the best of both worlds – reducing investment while also saving energy and cutting consumption? Or by-products of other categories. Are there any friends who are researching this area? Let’s discuss it together.
No boiler – projects that are better than those with a boiler
Could the original poster briefly explain whether you think there is waste heat unused in the production process? I think it’s almost all been utilized already; I’m also quite concerned about this issue – contact via in-site messages...
How is the waste heat from exhaust gases recovered?
Plate exchangers and air coolers for high-temperature water can be used to preheat cold chlorosilanes, but control is difficult; the temperature of the cold chlorosilanes is controlled by regulating the flow rate, thereby eliminating the need for electric heating or at least reducing electricity consumption. Perhaps hot water is relatively inexpensive, so not much attention has been paid to this aspect. As for the by-product steam, its thermal energy quality is low, hence it isn’t given much importance……&……
Very little of the heat from exhaust gases is utilized; it would be great if all of it could be used. I’m also thinking about this issue
Hasn’t any company considered the issue of recovering waste heat from exhaust gases? Why not recover the waste heat from exhaust gases?
Plate heat exchangers, air coolers – such familiar names.
I’m thinking that the steam generated on-site is already sufficient; is it really necessary to save energy in this way? And even if we do save energy, what’s the benefit? The reduction furnace still requires the same amount of electricity and still generates the same amount of steam – so what’s the use of having extra steam? . . . I’m a beginner and don’t quite understand these things yet; I hope everyone can help answer my questions. Thank you!
I’m thinking that the steam generated on-site is already sufficient; is it really necessary to save energy in this way? And even if we do save energy, what’s the benefit? The reduction furnace still requires the same amount of electricity and still generates the same amount of steam – so what’s the use of having extra steam? . . . I’m a beginner and not very familiar with these things; I hope everyone can help answer my questions. Thank you. Question: Where does the steam used for the reboiler in the secondary tank of a distillation tower come from? If waste heat is reused to generate steam, then the amount of steam produced by the boiler will decrease, which means cost savings