Hollow blade dryers are widely used in food, chemical, petrochemical, dye, industrial sludge and other fields. The heat transfer, cooling, and agitation characteristics of the equipment enable it to perform the following unit operations: calcination (low temperature), cooling, drying (solvent recovery), heating (thawing), reaction, and sterilization. The agitating blade is also a heat transfer surface, which increases the heat transfer area per unit effective volume and shortens the processing time. The wedge-shaped blade heat transfer surface has a self-cleaning function. Compression - the expansion and agitation function makes the material mix evenly. The material moves in a "plug flow" along the axial direction, and the temperature, humidity, and mixing gradient of the material are small in the axial interval. The heat transfer oil is used as the heat medium, and the paddle dryer can complete the low temperature calcination work. For example, calcium sulfate dihydrate (Ca2SO4·2H2O) is calcined and converted into calcium sulfate hemihydrate (Ca2SO4·1/2H2O). Sodium hydrogencarbonate (NaHCO3) is converted into soda ash (Na2CO3) by calcination. Cooling medium such as water, cooled brine, etc. can be used for cooling. For example, the paddle type alkali machine used in the soda ash industry replaces the old air cooling alkali machine, which saves energy and exhaust gas treatment equipment and reduces operating costs. Drying, the most important function of the equipment, does not use hot air, so that solvent recovery, energy consumption, and environmental control are in an ideal state of easy handling. It is especially suitable for the need to recover solvents, flammable and easily oxidizable heat sensitive materials. Has been widely used in fine chemicals, petrochemicals, dyes industry. The uniformity of temperature, humidity, and mixing in the axial section allows the equipment to be used to heat or melt, or to react with some solid materials. It has been successfully used in the compound fertilizer and modified starch industries. A paddle dryer can be used to sterilize food and flour. The large heating area in the effective volume of the unit quickly heats the material to the sterilization temperature, avoiding prolonged heating and changing the quality of the material.

The hollow blade dryer has the following characteristics:

1. The energy consumption of the blade dryer is low: due to indirect heating, there is not a large amount of air carrying heat, and the outer wall of the dryer is provided with an insulation layer. For the slurry material, only 1.2 kg of water vapor is required to evaporate 1 kg of water.

2, the blade dryer system cost is low: there is a huge heat transfer surface in the effective volume of the unit, which shortens the processing time and the device size becomes smaller. It greatly reduces the building area and building space.

3. Wide range of processing materials: Different heat media can be used to process both heat sensitive materials and materials requiring high temperature processing. Commonly used media are: water vapor, heat transfer oil, hot water, cooling water, etc. It can be operated continuously or intermittently and can be applied in many fields.

4. Small environmental pollution: no air is used, and dust materials are rarely entrained. The solvent evaporation of the material is small and easy to handle. Closed loops can be used for contaminated materials or for conditions requiring recovery of solvents.

5, low operating costs: the device operates normally, only 1 hour / day · people. Low speed mixing and reasonable structure. The amount of wear is small and the maintenance cost is low.

6. Stable operation: Due to the special compression-expansion and agitation of the wedge-shaped blade, the material particles are fully in contact with the heat transfer surface. In the axial interval, the temperature, humidity and mixing gradient of the material are small, thus ensuring Process stability.

Hollow blade dryer for materials

Petrochemical industry: polyolefin powder, polycarbonate resin, high and low density polyethylene, linear low density polyethylene, polyacetal granules, nylon 6, nylon 66, nylon 12, acetate, polyphenylene sulfide, propylene Base resin, engineering plastics, polyvinyl chloride, polyvinyl alcohol, polystyrene, polypropylene, polyester, polyoxymethylene, styrene-acrylonitrile copolymerization, ethylene-propylene copolymerization.

Environmental protection industry: electroplating sewage sludge, boiler soot, pharmaceutical factory waste residue, sugar factory waste residue, MSG factory waste residue, coal ash.

Feed industry: soy sauce residue, bone-based feed, distiller's grains, food scraps, apple pomace, orange peel, soybean meal, chicken bone feed, fish meal, feed additives, bio-sludge

Food industry: starch, cocoa beans, corn kernels, salt, modified starch, medicines.

Chemical industry: soda ash, NPK compound fertilizer, kaolin, bentonite, white carbon black, carbon black, phosphogypsum, oxidized sodium fluoride, calcium nitrate, magnesium carbonate, ***, aluminum hydroxide, barium sulfate, calcium sulfate, Calcium carbonate, dyes, molecular sieves, saponins.

Hollow paddle dryer: It can indirectly heat or cool paste, granule, powder and slurry materials, and can complete unit operations such as drying, cooling, heating, sterilization, reaction, low temperature calcination. The special wedge-type stirring heat transfer blade in the equipment has high heat transfer efficiency and self-cleaning function of the heat transfer surface.

The wedge-shaped hollow blade is densely arranged on the hollow shaft of the blade dryer, and the heat medium flows through the blade through the hollow shaft. The heat transfer area in the effective volume of the unit is large, and the temperature of the heat medium is from -40 ° C to 320 ° C. It can be water vapor or liquid type: such as hot water and heat transfer oil. Indirect conduction heating, no air is carried away to remove heat, and heat is used to heat the material. The heat loss is only the heat dissipation to the environment through the insulation of the body. The wedge-shaped blade heat transfer surface has a self-cleaning function. The relative movement of the material particles and the wedge surface produces a scrubbing action, which can wash away the adhering material on the wedge surface, so that a clean heat transfer surface is maintained during operation. The shell of the paddle dryer is of the omega type, and two to four hollow agitating shafts are generally arranged in the casing. The housing has a sealed end cap and an upper cover to prevent material dust from leaking out and collecting material solvent vapor. A baffle is arranged at the discharge port to ensure the height of the material level, so that the heat transfer surface is fully covered by the material. The heat transfer medium passes through the rotary joint and flows through the casing jacket and the hollow agitating shaft. The hollow agitating shaft has different internal structures according to the type of the heat medium to ensure an optimal heat transfer effect.