What is the principle of stripping tower? What separation is it mainly used for? Thank you

Generally, steam is used to extract residual gases such as NH3 in liquids.

Gas stripping uses inert gas to reduce the gas phase partial pressure of the solute, thereby achieving the purpose of solvent regeneration. The gas used for stripping is an inert gas, usually water vapor or nitrogen.

The principle of the stripping tower is the same as that of the fractionation tower. Mass transfer and heat transfer are achieved through the contact of the gas and liquid phases on the tray, so that components of different volatilities can be separated!

Concept stripping and gas stripping methods are used to remove dissolved gases and certain volatile substances from water. That is, the gas (carrier gas) is introduced into the water to fully contact each other, so that the dissolved gas and volatile substances in the water pass through the gas-liquid interface and transfer to the gas phase, thereby achieving the purpose of removing pollutants. Air or water vapor is commonly used as carrier gas. The former is called stripping and the latter is called stripping. 　　Principle The basic principles of stripping are gas-liquid phase equilibrium and mass transfer rate theory. For dilute solutions, at a certain temperature, when phase equilibrium is reached between gas and liquid, the partial pressure of the solute gas in the gas phase is proportional to the concentration of the gas in the liquid phase - Henry's law. 　　P=Ex where P——equilibrium partial pressure of solute gas in the gas phase, Pa ； x——equilibrium concentration of solute gas in the liquid phase, mole fraction ； E——Proportional coefficient, called Henry coefficient, Pa.

Our company uses nitrogen as stripping gas to treat the NHD rich liquid in the decarbonization tower. Increasing the nitrogen partial pressure on the surface of the rich liquid is to reduce the partial pressure of the acidic gas contained in the rich liquid. According to Henry's law (the partial pressure of the solute gas in the gas phase is proportional to the concentration of the gas in the liquid phase), the acidic gas in the rich liquid will precipitate and the solution will become a lean liquid for recycling. The principle of the deaerator is similar. It uses thermal deaeration to reduce the oxygen content in the water and prevent oxygen corrosion of the equipment.

Our factory has a sewage stripping tower, which uses heat exchange between steam and acidic water to volatilize and remove sulfides in the water.

Use the difference in solubility to separate gas and liquid substances: handshake

Can you explain in detail the structure of the sewage stripping tower, how to remove sulfide in sewage, and what is the removal rate? Hope to get your help, thank you.

How the air stripping tower works: Through direct contact with water vapor, the volatile substances in the stripped feed liquid are diffused into the gas phase in a certain proportion, thereby achieving the purpose of separating low-boiling point substances from the feed liquid. As for the second question asked by the author, it is difficult to answer. Air stripping towers are widely used in the chemical industry and separate a wide variety of materials. But the purpose of air lifting is: 1. Make the stripped material liquid purer. 2. Recover useful components in the stripping feed liquid. 3. When treating wastewater, the volatile toxic and harmful substances in the wastewater are diffused into the gas phase in a certain proportion, thereby achieving the purpose of separating pollutants from the wastewater.

In a refinery, gas stripping generally refers to sewage stripping that first separates the hydrocarbons in the sewage through pressure control, and then separates ammonia and hydrogen sulfide in the sewage through temperature control. The so-called temperature control is to use their volatility to control

The function of the stripping tower is to use the stripping steam at the bottom of the tower to separate the light components in the hydrogenated oil, such as C4~C1, H2S and other light components from the top of the tower. For hydrorefining, it is generally a total reflux. The bottom of the tower is the hydrogenated oil with H2S removed, and goes to the fractionation tower. Gasoline comes out from the top of the tower, and diesel is at the bottom of the tower. In fact, not all stripping tower tops are fully refluxed. When there are not many light components in hydrogenated diesel, naphtha can be extracted at the top of the tower to ensure that the flash point of the diesel at the bottom is qualified. In this case, a fractionating tower is not needed. The main function of the stripping tower is to remove hydrogen sulfide, and then go to the fractionating tower, and the entire fractionating tower is fractionated.

Stripping towers are used in many refinery units, but theoretical knowledge is rarely introduced.

The so-called stripping tower is a device for separation based on the difference in volatility of the gas and liquid phases or the obvious change in solubility with temperature changes. Its structure is very simple. There are packed towers and sieve plate towers, and their purpose is the same.

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A commonly used device in refineries, the stripping tower supplies water vapor to reduce the partial pressure of oil and vapor in the tower kettle and volatilize the distillate.

Haha, don’t forget that the atmospheric and vacuum towers of the refinery’s atmospheric and vacuum units generally also have stripping towers!

Gas stripping technology is applied in the production of urea. The urea reaction generates the intermediate product methylamine. In the stripping tower, the methylamine is decomposed and circulated by increasing the partial pressure of ammonia or CO2, so that high-concentration urine enters the subsequent separation system and increases the separation load of the post-urea process. Depending on the stripping medium, there are ammonia stripping methods and CO2 stripping methods.

This post was last edited by kaminocmyhc on 2010-12-15 09:36 Taking methanol as an example, the stripping tower uses medium-pressure steam to recover CO and H2 in alcoholic water and process condensate, which are equal to useful gases for synthesizing methanol, thus reducing the difficulty of water treatment. It mainly uses medium-pressure steam to pass in from below, and then the condensate is passed in from above, and the medium-pressure steam is used to bring out the gas in the condensate.

The principle of the stripping tower is the same as that of the fractionation tower. Mass transfer and heat transfer are achieved through the contact of the gas and liquid phases on the tray, so that components of different volatilities can be separated! Gas stripping uses inert gas to reduce the gas phase partial pressure of the solute, thereby achieving the purpose of solvent regeneration. The gas used for stripping is an inert gas, usually water vapor or nitrogen.