Drying equipment plays an important role in the pharmaceutical industry. However, there are so many drying equipments, which are related to the pharmaceutical industry, and how they are applied. Today, eight types of drying equipment will be used in the pharmaceutical industry for analysis. (1) Belt dryer The belt dryer consists of several individual unit sections. Each unit segment includes a circulation fan, a heating device, a separate or common fresh air intake system and an exhaust gas discharge system. The operating parameters of the quantity of drying medium, temperature, humidity and exhaust gas circulation amount can be independently controlled, so as to ensure the reliability of the dryer working and the optimization of the operating conditions. The belt dryer has the advantages of flexible operation, wet material feeding, and drying process in a completely sealed box. The working conditions are good, and the leakage of dust is avoided. It is especially suitable for the drying of sheets, strips, and granular materials with good air permeability, especially for dehydrated vegetables, Chinese Herbal Pieces, etc., which have high water content and material temperature is not allowed to be high. (2) roller scraper dryer Roller squeegee dryer is a kind of continuous operation equipment that is used to heat the liquid phase material or strip-like material attached to the outer wall of the cylinder through a rotating cylinder to conduct heat drying. The liquid to be dried is fed from the high tank to the receiving tank of the drum dryer. The drying drum is driven by the transmission and rotates at a specified speed. The material is formed by a cloth film device to form a material film on the wall surface of the drum. The heating medium is continuously fed into the cylinder, the cylinder body is heated, the heat of the material membrane is vaporized by the heat transfer from the cylinder wall, and then the material required for drying is scraped off by a scraper, and conveyed to the storage tank by spiral and packaged. The moisture removed by evaporation can be introduced into the corresponding treatment device depending on the nature of the moisture through a closed hood; generally water vapor can be directly discharged from the exhaust pipe at the top of the hood to the atmosphere. The machine is mainly used for processing liquid materials, which can be heated by steam, hot water or hot oil, and can also be cooled by cooling water. According to different material properties and process requirements, immersed, spray-type, grind-assisted and other feeding methods can be adopted. (3) Hollow blade dryer (blade dryer) Hollow blade dryer, also known as blade dryer, is mainly composed of W-shaped shell with jacket and two hollow blade shafts and transmission device. A hollow blade is arranged on the shaft, and the shaft end is equipped with a rotating medium introduced by a rotary joint. The heat required to dry the moisture is conducted to the material by the inner wall of the jacket with W-shaped grooves and the hollow blade wall. During the drying process of the material, the hollow shaft with the hollow blade stirs the material while heating the material, thereby updating the heating surface. It is a continuous conduction heating dryer. The heating medium is steam, hot water or heat transfer oil. The heating medium is introduced into the jacket of the housing and in the two hollow blade shafts, and the material is heated and dried in a conductive heating manner. Different material hollow blade shaft structures are different. The machine is suitable for processing various paste-like, granular, powdery and other materials with good thermal stability. Under special conditions, it can also dry heat sensitive materials and recover the solvent during the drying process. It is commonly used for the drying or cooling of carbon black, light calcium carbonate, titanium dioxide, barium carbonate, nitrile uric acid, gypsum, clay, manganese dioxide, nylon and polyester chips, polyethylene, polypropylene (recovery solvent) and other materials. The dry material is added from the middle of the upper part of the shell of the vacuum rake dryer. Under the stirring of the continuously rotating rake, when the material comes into contact with the housing wall, the surface is continuously updated, and the dried material is subjected to steam (or hot water, heat transfer oil). Indirect heating, but the material moisture vaporization, vaporized water pumped away in time by the vacuum pump. The material to be dried is indirectly heated by the heat carrier, so that the moisture in the material is vaporized and vaporized water is discharged in time by the vacuum pump. Due to the high operating vacuum, generally in the range of 400-700mmHg, the surface water vapor pressure of the dried material is much greater than the vapor pressure of the evaporation space in the dryer shell. It is beneficial to the discharge of moisture and surface moisture in the dried material, which is beneficial to the movement of the water molecules in the dried material and achieves the purpose of drying. Vacuum rake dryers are suitable for heat-sensitive materials that are easily oxidized at high temperatures or materials that tend to harden when dried, and materials that must be recycled when the steam is discharged during drying. Typical dry materials are sodium acrylate, CMC, phthalocyanine blue, dye intermediates, carboxymethyl starch, maltodextrin, decanesulfonic acid, and the like. (5) Double cone rotary vacuum dryer The double-cone rotary vacuum dryer is slightly olive-like, with two ends covered and two shafts in the middle to support the body. The body has a jacket for heating, the body can be rotated when dry, so that the material and the wall are often replaced contact, overcome the shortcomings of the material in the vacuum oven mainly rely on the heating tube conduction and low thermal efficiency. Rotary vacuum dryers have been widely used in fine chemicals, medicines, etc., and are not suitable for materials with high viscosity or strong adhesion during rotation. The equipment is mainly used for the concentration, mixing and drying of powdery, granular and fibrous materials in the pharmaceutical, chemical and food industries, as well as materials requiring low-temperature drying (such as biochemical products, etc.), and is more suitable for easy oxidation, volatile, and heat-sensitive. Strongly irritating, toxic materials, and materials that are not allowed to damage the crystals are dried. (6) Spray Dryer Spray drying is the most widely used process in the liquid process forming and drying industry. It is most suitable for the production of powdery, granular solid products from solutions, emulsions, suspensions and pasty liquid raw materials. Therefore, spray drying is a very desirable process when the finished product particle size distribution, residual moisture content, bulk density, and particle shape must meet exacting standards. (7) Vacuum oven Due to the decompression, the evaporation temperature of the volatile matter contained in the evaporation of the material can be reduced, which is suitable for the drying of various heat-sensitive and easily oxidized materials. This device is often a cylinder or other vacuum-operated housing. It is heated by electric or hot water and heat-conducting oil through a heating plate or a heating tube. It is suitable for small batch batch production. The oven is a universal drying equipment with a wide range of applications. It is a tray-type intermittent drying equipment used in pharmaceuticals, chemicals, and foods. Light industry, heavy industry and other industries materials and products heat curing, drying and dehydration. Such as raw materials, crude drugs, Chinese Herbal Medicine, extracts, powders, granules, granules, water pills, bottles, pigment dyes, dehydrated vegetables, dried fruits, sausages, plastic resins, electrical components, baking and so on. (8) Rotary Flash Dryer The dried material enters the drying chamber through the screw feeder and is crushed by the stirring paddle at the lower part of the dryer. The crushed material is in full contact with the hot air. It flows upwards and is dried under the double action of the stirring paddle and the air distributor, and passes through the classifier. The sieved material with acceptable particle size and humidity was allowed to dry down until it passed. Product features: Fast drying speed. The dryer can be completed in 1-10 seconds; the material residence time can be adjusted. Can be adjusted between 1-500s, suitable for heat-sensitive materials drying; a variety of feeding devices for selection, feeding continuous and stable, will not produce bridging phenomenon; drying chamber high gas velocity, material residence time is short, effectively prevent materials The viscous and thermosensitive materials are deteriorating; the drying chamber is equipped with a grading ring and a cyclone sheet, the material fineness and final moisture are adjustable, and the drying strength is high. ANPING COWAN WIRE MESH & MACHINES CO., LTD , https://www.cowanfences.com
(4) Vacuum rake dryer
October 21, 2023