What is distillation?
It is to use the difference in the volatility of the components in the liquid mixture to partially vaporize the liquid mixture and then partially condense the vapor, thereby achieving the separation of the components contained in it. It is a unit operation of mass transfer separation. It is widely used in oil refining, chemical industry, light industry and other fields.
What Equipment is Used in Distillation
- Wiped Film Distillation Equipemnt
- Short Path Distillation Equipment
What are the Steps of Distillation?
Distillation is a thermodynamic separation process, which utilizes the different boiling points of each component in a mixed liquid or liquid-solid system to evaporate the low-boiling component and then condense to separate the entire component. Distillation is a combination of two unit operations, evaporation and condensation.
Compared with other separation methods, such as extraction, filtration crystallization, etc., the advantage of distillation is that it does not need to use other solvents other than system components, thus ensuring that no new impurities are introduced.
The Application of Distillation in Industry
1) Petroleum refining industry (crude oil → gasoline, kerosene, diesel oil, etc.);
2) Petrochemical industry (separation of basic organic raw materials, petroleum cracking gas, etc.);
3) Air separation (preparation of oxygen and nitrogen);
4) Food processing and pharmaceutical production.
Simple Distillation VS. Wiped Film Distillation
Wiped Film Distillation is a special liquid-liquid separation technology. Unlike traditional distillation, which relies on boiling point difference. Wiped Film Distillation relies on the difference in the mean free path of molecular motion of different substances to achieve separation.
1. Different Purposes
Wiped Film Distillation is often used to separate components with small boiling point differences, while simple distillation is usually used to separate components with large boiling point difference as well as separate liquids from solid impurities.
2. Different Pros and Cons
Wiped Film Distillation can purify liquids containing several different components better even though there are small boiling point differences. But it requires more energy, slower and more complex than Simple Distillation.
So on the other hand, Simple Distillation is faster and simpler, requiring less energy. But it can only be used for the separation of relatively pure liquids and there should be a large boiling point differences between components.
In conclusion, there are various pros and cons between Wiped Distillation Distillation and Simple Distillation.
What are the Types of Distillation?
1. According to the method: simple distillation, balanced distillation, rectification, special distillation;
2. According to the operating pressure: normal pressure, pressurization, and decompression;
3. According to the components in the mixture: two-component distillation, multi-component distillation;
4. According to the operation mode: batch distillation, continuous distillation.
Short Path Distillation
Short path distillation is also known as molecular distillation.
A complete set of molecular distillation equipment includes: molecular evaporator, degassing system, feeding system, heating system, cooling vacuum system and control system.
The core part is the molecular evaporator, which has the following types: A: Falling Film Type,B: Wiped Film Type, C: centrifugal type.
The pressure difference between the boiling film and condensing surface is the driving force of the stem flow, and the minimum pressure will cause the flowing of steam. Under the 1mbar, the operation requires that there is the shortest distance between the boiling surface and condensing surface. The evaporator manufactured based on the principle is known as the short-path distillation. The short-path distillation (molecular distillation) is equipped with a inside condenser which is opposite to the heating surface, and make the operation pressure reduce to under 0.001mbar. Its relative low boiling temperature is very suitable for the material with heat sensitive and high boiling point.
Short Path Distillation for Sale
Wiped Film Molecular Distillation
Wiped Film Molecular Distillation is a distillation method under high vacuum.
The average free path of the vapor molecules is greater than the distance between the evaporation surface and the condensation surface, so that the difference in evaporation rate of each component in the liquid can be used.
Molecular distillation is to separate the mixtures of liquids.
