Application of eight kinds of drying equipment in chemical and pharmaceutical industry

Drying equipment is widely used in industry, and the use of drying equipment is needed in many fields. Similarly, drying equipment also plays an important role in the pharmaceutical industry. Today, the author will bring eight kinds of drying equipment in the chemical pharmaceutical industry application. The application of eight kinds of drying equipment in chemical and pharmaceutical industry.

(1) Belt dryer

The strip dryer consists of several separate units. Each segment includes a circulation fan, a heating device, a separate or public fresh air intake system and a exhaust exhaust system. The operating parameters of dry medium quantity, temperature, humidity and exhaust circulation can be controlled independently, so as to ensure the reliability and optimization of operating conditions. With the flexible operation of the dryer, wet material feed, drying process in a completely sealed box, working conditions are good, to avoid the leakage of dust. Used for the drying of thin, strip, and granular materials with good permeability, it is particularly suitable for materials with high water content such as dehydrated vegetables and traditional Chinese medicine tablets and high material temperature.

(2) Roller scraper dryer

A drum scraper dryer is a continuous operation device that uses a rotating cylinder to dry liquid or banded materials attached to the outside wall of the cylinder by means of heat conduction. The material liquid that needs to be dried is fed into the receiving tank of the drum dryer from the high tank. The drying drum is driven by the transmission device and rotates at the prescribed speed. The material consists of a cloth film device that forms a material film on the wall of the drum. The cylinder is continuously fed into the heating medium and heated. The heat transfer from the cylinder wall causes the wet vaporization of the material film, and then the material that meets the drying requirements is scraped off by a scraper and sent to the storage tank via a screw for packaging. The wet points removed by evaporation, depending on their properties, can be introduced into the corresponding treatment device through a closed cover; Generally water vapor can be placed directly from the exhaust pipe on the top of the cover into the atmosphere. The machine is mainly used for the treatment of liquid materials, which can be heated and dried by steam, hot water or hot oil, and can also be cooled by cold water. According to different material properties and process requirements, we can use immersion, spray, and milling.

(3) Hollow blade dryer(blade dryer)

The hollow blade dryer, also known as the blade dryer, consists mainly of a W-shaped shell with a jacket and two hollow blade shafts and transmission devices. The shaft is arranged with hollow leaves and the shaft end is equipped with a rotating joint imported from a hot medium. The heat required for drying moisture is transmitted to the material from the inner wall of the W groove with a jacket and the wall of the hollow blade. During the drying process, the hollow shaft with the hollow blade heats the material while stirring the material to update the heating surface. It is a continuous conduction heating dryer. The heating medium is steam, hot water or heat conducting oil. The heating medium is passed into the shell jacket and the two hollow oars shaft, and the material is heated and dried by conduction heating. The structure of the hollow oars shaft of different materials is different.
The machine is suitable for treating all kinds of materials with better thermal stability such as paste, granule, powder, etc.. It can also dry heat-sensitive materials under special conditions and recover solvents during drying. Commonly used for the drying or cooling of materials such as carbon black, light calcium carbonate, titanium dioxide, Barium carbonate, nitrile uric acid, gypsum, clay, manganese dioxide, nylon and polyester slices, polyethylene, and polypropylene(recovered solvent).

(4) Vacuum rake dryer

Dry material is added directly above the shell of the vacuum rake dryer. When the material is in contact with the wall of the shell, the surface is constantly updated and the dry material is indirectly heated by steam(or hot water, heat conducting oil).It is the vaporization of the material moisture, vaporization of the water from the vacuum pump in a timely manner. The drying material is indirectly heated by the heat carrier, so that the moisture in the material vaporizes, and the vaporized water is discharged from the vacuum pump in time.
Due to the high operating vacuum, generally in the range of 400-700 mmHg, the water vapor pressure on the surface of the dried material is much greater than the water vapor pressure in the evaporation space of the dryer shell. Thus, it is beneficial to the discharge of the internal moisture and surface moisture of the dry material, and is conducive to the movement of the water molecules of the dry material to achieve the purpose of drying. Vacuum rake dryers are suitable for heat sensitivity, materials that are easily oxidized at high temperatures or that are easily knotted during drying, and materials that need to be recovered from steam discharged during drying. Typical drying materials include sodium acrylate, CMC, phthalocyanine blue, dye intermediates, carboxymethyl starch, maltodextrin, and anthraquinone sulfonic acid.

(5) Double conical rotary vacuum dryer

The double-cone rotary vacuum dryer is slightly olive-shaped, with two ends covered and two axes in the middle to support the body. The body of the device has a jacket to heat, and the drying timer body can be rotated so that the material and the wall of the device can be changed and contacted frequently, overcoming the disadvantage that the material in the vacuum oven mainly depends on the heating tube and the heat efficiency is low. The rotary vacuum dryer has been widely used in fine chemicals, medicine, etc.. It is not suitable for materials with large viscosity or strong adhesion in the rotary process. The equipment is mainly used for the concentration, mixing, drying and low-temperature drying of powder, granular and fibrous materials(such as biochemical products) in the pharmaceutical, chemical, and food industries. It is more suitable for the drying of easily oxidized, volatile, highly sensitive, toxic materials and materials that do not allow damage to crystals.

(6) Spray dryer

Spray drying is a widely used process in liquid forming and drying industry. Suitable for producing powdered, granular solid products from solution, emulsion, suspension and paste liquid raw materials. Therefore, spray drying is an ideal process when the particle size distribution, residual water content, accumulation density and particle shape of the finished product must meet accurate standards.

(7) Vacuum oven

Due to decompression, the evaporation temperature of volatiles contained in the evaporation of materials can be reduced, which is suitable for the drying of various heat-sensitive and oxidizing materials. This device is often a garden tube or other shell that can withstand vacuum operation. It is heated by electrothermal or hot water, heat conduction oil through a heating plate or heating pipe, and is suitable for small batch intermittent production.
The oven is a general drying equipment, the application surface is wider, is a disc stand type intermittent drying equipment, applied to pharmaceuticals, chemicals, food. Heating, curing, drying and dehydration of materials and products in light industry and heavy industry. Such as raw materials, raw drugs, traditional Chinese medicine, extract, powder, particles, punching, water pills, packaging bottles, pigment dyes, dehydrated vegetables, dried melons, sausages, plastic resins, electrical components, baking paint, etc..

(8) Rotation flash dryer

The dried material enters the drying chamber through a spiral input and is crushed by the stirring paddle in the lower part of the dryer. After the crushed material is in full contact with the hot air, it flows upwards and dries under the dual action of the stirring paddle and the airflow distributor. After screening granularity and humidity of the classifier, the material is turned under drying until it is qualified.
Product characteristics: fast drying speed. 1 to 10 seconds to complete the dryer; Material residence time can be adjusted. It can be adjusted between 1-500s and is suitable for the drying of heat-sensitive materials; A variety of feed devices are available for selection, and the feed is continuous and stable, and there is no bridge construction phenomenon. The drying indoor circumferential gas speed is high, and the material stay time is short. The drying chamber is equipped with a graded ring and a swirling sheet. The fineness and final moisture of the material can be controlled. High drying strength.