[Q&A] Catalytic Coking Reformate Blending Version 20170815
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This post was last edited by Green Lotus on 2017-8-15 11:49. What are the necessary conditions for a distillation process to take place? Answer: The establishment of temperature and concentration gradients along the height of the distillation column, as well as the presence of contact facilities, are necessary conditions for the distillation process to take place. http://bbs.hcbbs.com/static/image/hrline/4.gif Note: The answer will be released automatically after two days. Petrochemical Zone – “Creative Ideas for Energy Savings” event (the second phase is in full swing): http://bbs.hcbbs.com/thread-1666758-1-1.html. 2017: “My Technical Upgrades” in the field of coal chemical industry: http://bbs.hcbbs.com/thread-1786290-1-1.html. [Daily Question] Summary post for 2017 on catalyst-based coking and reformed oil blending: http://bbs.hcbbs.com/thread-1811219-1-1.html. [Q&A] Summary post for 2017 on catalyst-based coking and reformed oil blending: http://bbs.hcbbs.com/thread-1826018-1-1.html
The establishment of temperature and concentration gradients along the height of the distillation column, as well as the presence of contact facilities, are necessary conditions for the distillation process to take place.
The method of separating the various components in a liquid or gaseous mixture by taking advantage of their differences in volatility or boiling points is called distillation. The necessary conditions for distillation are: (1) thorough contact between the gas and liquid phases; multiple trays inside the distillation column serve to ensure such thorough contact; (2) when the gas and liquid phases come into contact, the concentration of light components in the rising hot gas phase should be higher than the equilibrium concentration, while the concentration of light components in the descending cold liquid phase should be lower than the equilibrium concentration. It is this imbalance between the gas and liquid phases, along with the temperature difference, that enables heat and mass transfer to occur, thus facilitating the process of distillation.
The method of separating the various components in a liquid or gaseous mixture by taking advantage of their differences in volatility or boiling points is called distillation. The necessary conditions for distillation are: (1) thorough contact between the gas and liquid phases; multiple trays inside the distillation column serve to ensure such thorough contact; (2) when the gas and liquid phases come into contact, the concentration of light components in the rising hot gas phase should be higher than the equilibrium concentration, while the concentration of light components in the descending cold liquid phase should be lower than the equilibrium concentration. It is this imbalance between the gas and liquid phases, along with the temperature difference, that enables heat and mass transfer to occur, thus facilitating the process of distillation.
Rising vapor and descending liquid are two essential conditions in the distillation process
(1) The gas and liquid phases must be in full contact, and the multiple layers of trays installed in the distillation tower provide the conditions for such full contact between the gas and liquid phases; (2) When the gas and liquid phases are in contact, the concentration of light components in the rising hot gas phase is higher than the equilibrium concentration, while the concentration of light components in the descending cold liquid phase is lower than the equilibrium concentration. Heat and mass transfer can occur only due to this imbalance between the gas and liquid phases as well as the temperature difference, which enables the distillation process to take place
The gas phase, the liquid phase, and the area where they come into contact – the tray.
The establishment of temperature and concentration gradients along the height of the distillation column, along with the presence of contact facilities, are necessary conditions for the distillation process to take place
1. The gas phase temperature is higher than the liquid phase temperature； 2. The concentration of low-boiling components in the liquid phase is higher than the concentration at equilibrium in the gas phase ； 3. A place where the gas and liquid phases can come into full contact.
Backflow is a necessary condition for the mass transfer that occurs at the interface between vapor and liquid, enabling the distillation process to proceed continuously
The volatilities cannot be the same; there must be gas-phase reflux and liquid-phase reflux, as well as a site for mass and heat transfer through gas-liquid contact: tray plates or packing. There are imbalances between the gas and liquid phases between the tray plates: concentration differences and temperature differences