Reissue of 【One Question per Day】12.15 Short Answer Question: What is the purpose of stripping?

The steam used for steam stripping has two main functions: 1. To reduce the vapor pressure of the oil, thereby decreasing the degree of oil vaporization and facilitating product separation. 2. Supply heat to the stripping tower. In actual normal production, since the tower diameter remains constant ； Excessive steam injection can result in an overly large volume of rising steam ； It is easy for the linear velocity of the gas inside the tower to exceed the allowable limit, resulting in a tower surge accident. To this end, the steam injection amount is 3 percent of the feed volume; the heat capacity of the steam remains constant at a fixed temperature ； If more heat is to be provided, the most direct method is to increase the steam injection ； For the above reasons, steam injection is primarily used to reduce the oil-vapor partial pressure. In diesel and gasoline hydrogenation units, as the stripping temperature decreases, the heat available for vaporizing the feed oil decreases ； A decrease in the vaporization rate of the components will result in a lower flash point (the impact is not significant). Excessively high stripping steam facilitates the precipitation of hydrogen sulfide, ammonia, and light hydrocarbons; however, at a constant steam injection rate, such high steam levels increase the cooling load at the top of the tower ； The temperature should not exceed 400 degrees.

What is the purpose of stripping? Stirring is a process in which wastewater is brought into direct contact with water vapor, allowing volatile toxic and harmful substances in the wastewater to diffuse into the gas phase in a certain proportion, thereby achieving the separation of pollutants from the wastewater.

:1. Reduce the partial pressure of oil and gas and increase the relative volatility, thereby facilitating the recovery of light components. 2. Displace the light components

1. Reducing the partial pressure of oil and gas increases the vaporization rate, which is beneficial for product separation. 2. Provide heat to the stripping tower and the reactor.

The light-boiling components in the mixture are carried away by steam in a certain proportion

What is the purpose of the stripping method? Stirring extraction is similar to stripping, except that a different medium is used; stirring extraction is accomplished with the help of water vapor as the medium. A carrier gas such as air or water vapor is introduced into the water, allowing the carrier gas to come into full contact with the wastewater; this causes the dissolved gases and certain volatile substances in the wastewater to transfer into the gas phase, thereby achieving the removal of pollutants from the water. According to the principle of phase equilibrium, in a liquid mixture at a constant temperature, each component has an equilibrium partial pressure. When the equilibrium partial pressure of that component in the gas phase in contact with the liquid phase approaches zero, and the equilibrium partial pressure in the gas phase is much lower than that in the liquid phase, the component will transfer from the liquid phase to the gas phase – this is the principle of stripping. When air is generally used as the carrier gas, it is called stripping ； Using steam as the carrier gas is called stripping. The process of separating pollutants using the stripping method varies depending on the nature of the pollutants, and can generally be divided into the following two types: Simple distillation is used for volatile substances that are miscible with water, taking advantage of the fact that under gas-liquid equilibrium conditions, their concentration in the gas phase is higher than that in the liquid phase. It is directly heated by steam, causing it to become enriched in the gas phase at a certain proportion at its boiling point (a temperature between the boiling points of water and the volatiles). Steam distillation is suitable for volatile pollutants that are immiscible or almost immiscible with water. Taking advantage of the fact that the boiling point of the mixture is lower than that of its components, high-boiling volatile substances can be separated and removed at lower temperatures. For example, substances such as turpentine, aniline, phenols, and *** in wastewater can be separated using distillation at temperatures below 100°C. The main equipment for stripping is the stripping tower, which falls into two categories: packed towers, in which various types of packing are placed in layers inside the tower – (1) random packing, (2) structured packing, (3) capillary packing; and tray towers, which are further divided according to the structure of their trays into: (1) bubble cap towers, (2) floating valve towers, (3) sieve plate towers. Tray towers have higher efficiency than packed towers

What is the purpose of stripping? Stirring is a device that uses gas passing through a liquid to carry away the components within that liquid that need to be removed.

What is the purpose of stripping? Through direct contact between wastewater and water vapor, the toxic and harmful substances present in the wastewater diffuse into the gas phase in a certain proportion, thereby achieving the goal of separating these gaseous substances from the wastewater.

Atmospheric stripping enables a better separation of the fractions. A catalytic stripping tower is used to reduce the excessive light components (gasoline-like components) in light diesel, thereby controlling its flash point; too many light components in diesel result in a lower resistance to detonation.