Short-path distillation, "short-path" refers to a short path. In a broad sense, the evaporator adopts a design scheme where the distance from the evaporation surface to the condensation surface is less than 300MM, which can be called a short-path still. In terms of design and structure, it is divided into scraped short-path distiller, centrifugal short-path distiller and short-path distiller evolved from the installation position of condenser of thin-film evaporator improved by some manufacturers in recent years. The short path distillation kit thc equipment is a special liquid mixture that separates the liquid mixture by using the difference in the evaporation rate of the components in the feed liquid under the high vacuum state, so that the mean free path of the vapor molecules is greater than the distance between the evaporation surface and the condensation surface. - Liquid separation technology. It is not only used in the field of medicine, petroleum, but also widely used in the field of food.
At present, the most mature and widely used technology is the scraped short-path distiller, which is designed to be composed of an externally heated vertical evaporation cylinder, a central condenser and a scraper rotating between the distiller and the condenser. The short path distillation equipment for sale process is as follows: the material is added from the top of the evaporator, and is continuously and evenly distributed on the heating surface by the material-liquid distributor on the rotor, and then the film scraper scrapes the material into a thin layer of turbulent liquid. membrane and advance downward in a spiral. During this process, the light components escaping from the heating surface are condensed into liquid on the built-in condenser after a short route and almost without collision, and flow down along the condenser tube through the outlet at the bottom of the evaporator. The material pipe is discharged; the residual liquid, that is, the heavy components, is collected in the circular channel under the heating zone, and then flows out through the side discharge pipe.
Molecular distillation, more precisely the principle of molecular distillation, is different from the traditional distillation which relies on the separation principle of boiling point difference, but relies on the difference in the mean free path of molecular motion of different substances to achieve separation. In the short path distillation kit thc process, when the liquid mixture flows along the heating plate and is heated under a certain pressure condition, the light and heavy molecules will escape from the liquid surface and enter the gas phase. Molecules of substances move at different distances after escaping from the liquid surface. If a condensing plate can be properly installed (the distance between the condensing surfaces of the evaporation area is generally less than 100MM), the light molecules reach the condensing plate and are condensed and discharged, while the heavy molecules cannot reach the condensing plate. Drain along the mixture. This achieves the purpose of material separation.
Attention should be paid to "specific pressure conditions" and "evaporation area condensation surface distance" from the distillation process description. That is to say, not all raw materials can achieve molecular distillation; the molecular distillation process can only be realized in a scraped short path still or a centrifugal short path; Molecular-level motion at a specific pressure and a specific temperature and realize the separation process. Therefore, it is wrong to simply confuse molecular distillation with short path distillation equipment for sale, and its essence is different.
Features of short path distiller:
Features of the scraped short-path distiller: Extremely high vacuum: The special structural design of the scraped short-path distillation allows the operating pressure to reach extremely low operating vacuum. The vacuum of the experimental-scale equipment can reach 0.001mbar, and even the industrial-scale equipment can reach 0.01 mbar. -0.05mbar. The operating temperature is much lower than the boiling point of the material: because the scraper short path distillation kit thc adopts the central condensation method, the distance between the condensation surface of the evaporation area is generally less than 50mm (the distance of the experimental device is less than 10mm), so that there is only a slight pressure drop between the evaporator and the condenser. That is to say, the vacuum degree at the end of the vacuum system is almost close to that of the evaporator. DEA is designed to fully meet the realization conditions of molecular distillation process.
Short heating time: It is designed by using a vertically rotating scraper to form a film, and the residence time of the material on the heating wall is only ten seconds. Due to the strict distance requirement between the heating wall of the short-path distillation and the condenser, the light molecules escaping from the liquid surface reach the condensing surface almost instantaneously, and the heating time of the vapor-phase light molecules can be ignored in this process. The possibility of thermal decomposition is minimized. Excellent mass transfer and heat transfer efficiency: DEA short path distillation equipment for sale adopts a mechanical scraping film system, which is different from other defects such as the uneven film formation of falling film evaporators. The area of the surface and the heating surface are almost equal, and the mass transfer and heat transfer efficiency is superior.
Precautions for the use of short-path glass distillation:
No-load operation is not suitable for high-speed operation;
Keep the speed regulation and motor dry, because the life of the electrical box and the surrounding humidity and temperature have a great influence;
The bottom line must be well grounded, and the high temperature bath must be connected to the air switch;
Throwing it within 5 minutes after cutting off the power supply may cause electric shock due to the discharge of the inverter or capacitor;
Please avoid the impact damage to the glass by hard objects such as watches and rings when operating the instrument;
When the glass reactor needs to be heated, the temperature should be gradually increased, especially when heated at high temperature, it is generally recommended to use heat transfer oil that is less harmful to the human body