The main products of zzkd are distillation and extraction equipment，and molecular distillation equipment  is one of them, which is mainly used to extract essential oil,the products are sold to the USA, Canada, Brazil, India and other dozens of countries.

Molecular distillation is a distillation method operated in high vacuum. It is a special liquid-liquid separation technology.In high vacuum, the average free path of vapor molecules is larger than the distance between evaporation surface and condensation surface, so the liquid mixture can be separated by the difference of evaporation rate of each component in feed liquid.

At a certain temperature, the lower the pressure, the greater the average free path of gas molecules.When the pressure of evaporation space is very low (10-2 ~ 10-4 mmHg), and the condensation surface is close to the evaporation surface, and the vertical distance between them is less than the average free path of gas molecules, the vapor molecules vaporized from the evaporation surface can reach the condensation surface directly without collision with other molecules and condense.

Different from traditional distillation, molecular distillation relies on the principle of boiling point difference, but on the difference of average free path of molecules of different substances.When the liquid mixture flows along the heating plate and is heated, the light and heavy molecules will escape from the liquid surface and enter the gas phase. Due to the different free paths of the light and heavy molecules, the molecules of different substances will move at different distances after escaping from the liquid surface. If a condensation plate can be set properly, the light molecules will be condensed and discharged from the condensation plate, while the heavy molecules will not be able to reach the condensation plate and be discharged along the mixture. In this way, material separation can be achieved.
 
The pressure difference between the boiling film and the condensing surface is the driving force of the steam flow direction. For a small pressure drop, the steam will flow.Operating at 1mbar requires a very short distance between the boiling surface and the condensing surface. The short range distiller (molecular distillation) has a built-in condenser opposite the heating surface and reduces the operating pressure to 0.001 mbar.

The short-range distiller is a process of thermal separation under the pressure of 1 ~ 0.001 mbar. It has a lower boiling temperature and is very suitable for heat sensitive and high boiling point substances.Its basic composition: cylindrical cylinder with heating jacket, rotor and built-in condenser; film scraper and splash proof device are precisely installed on the fixed frame of rotor. The built-in condenser is located in the center of the evaporator, and the rotor rotates between the cylindrical cylinder and the condenser.

The distillation process is: the material is added from the top of the evaporator, and it is continuously and evenly distributed on the heating surface through the feed liquid distributor on the rotor, and then the film scraper scrapes the material liquid into a thin, turbulent liquid film, and advances downward in a spiral shape.In this process, the light molecules escaping from the heating surface will condense into liquid on the built-in condenser after a short route and almost without collision, and then flow down the condenser tube and discharge through the discharge pipe at the bottom of the evaporator; the residual liquid, namely heavy molecules, is collected in the circular channel under the heating zone, and then flows out through the side discharge pipe.