brief introduction
The double blade dryer indirectly conducts heating without carrying away heat with air, and the heat is used to heat the material. The special wedge-shaped stirring heat transfer blade in the equipment has high heat transfer efficiency and self-cleaning function of the heat transfer surface, with a large heat transfer area per unit effective volume. The heat medium can be water vapor, hot water, thermal oil, etc. The heat transfer medium flows through the shell jacket and hollow stirring shaft through the rotary joint. The hollow stirring shaft has different internal structures according to the type of heat medium to ensure the best heat transfer effect. The shell of the blade dryer is Ω - shaped, and generally two to four hollow mixing shafts are arranged inside the shell. The shell has sealed end caps and upper caps to prevent material dust leakage and collect material solvent vapor. Set up a stopper at the discharge port to ensure the height of the material level, so that the heat transfer surface is covered by the material and fully functional. [1]
characteristic
1. The double blade dryer has low energy consumption: due to indirect heating, it does not carry a large amount of air to take away heat. The outer wall of the dryer is also equipped with an insulation layer. For slurry materials, only 1.2kg of water vapor is needed to evaporate 1kg of water. 2. The cost of the blade dryer system is low: it has a huge heat transfer surface per unit effective volume, which shortens processing time and reduces equipment size. This greatly reduces the building area and space. 3. Wide range of material processing: using different heat media, it can handle both thermosensitive materials and materials that require high-temperature treatment. Common media include steam, thermal oil, hot water, cooling water, etc. It can operate continuously or intermittently and can be applied in many fields. 4. Low environmental pollution: No use of portable air, minimal dust and material entrainment. The solvent evaporation of the material is very small, making it easy to handle. For materials that are contaminated or require solvent recovery, closed-loop circulation can be used. 5. Low operating costs: The device operates normally, with only 1 hour/day per person. Low speed stirring and reasonable structure. The wear and tear is small, and the maintenance cost is very low. 6. Stable operation: Due to the special compression expansion stirring effect of the wedge-shaped blade, the material particles are fully in contact with the heat transfer surface. In the axial range, the temperature, humidity, and mixing gradient of the material are very small, thereby ensuring the stability of the process.
application area
The double blade dryer has been successfully used in fields such as food, chemical, petrochemical, dye, and industrial sludge. The characteristics of heat transfer, cooling, and stirring of the equipment enable it to perform the following unit operations: calcination (low temperature), cooling, drying (solvent recovery), heating (melting), reaction, and sterilization. The mixing 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 also has self-cleaning function. The compression expansion mixing function ensures uniform mixing of materials. The material moves in a "piston flow" along the axial direction, and within the axial range, the temperature, humidity, and mixing gradient of the material are very small. Using thermal oil as the heat medium, the blade dryer can complete low-temperature calcination work. For example, calcium sulfate dihydrate (Ca2SO4 · 2H2O) is calcined and converted into calcium sulfate hemihydrate (Ca2SO4 · 1/2H2O). Sodium bicarbonate (NaHCO3) is converted into pure alkali (Na2CO3) through calcination. Cooling media such as water, cooling salt water, etc. can be used for cooling. For example, the blade type cooling alkali machine used in the soda ash industry replaces the old-fashioned air-cooled cooling alkali machine, saving energy and exhaust gas treatment equipment, and reducing operating costs. Drying, the main function of the equipment, does not use hot air, making solvent recovery, energy consumption, and environmental control in an ideal state that is easy to handle. It is particularly suitable for solvents that need to be recycled, flammable and easily oxidizable heat sensitive materials. It has been widely used in the fine chemical, petrochemical, and dye industries. The uniformity of temperature, humidity, and mixing degree within the axial range allows the equipment to be used for heating or melting, or for some solid material reactions. It has been successfully used in the compound fertilizer and modified starch industries. A blade dryer can be used to sterilize food and flour. The large heating area within the effective volume of the unit quickly heats the material to the sterilization temperature, avoiding prolonged heating and changing the quality of the material.
Adapt to materials
Petrochemical industry: polyolefin powder, polycarbonate resin, high and low density polyethylene, linear low density polyethylene, polyacetal particles, nylon 6, nylon 66, nylon 12, acetate fiber, polyphenylene sulfide, propylene based resin, engineering plastics, polyvinyl chloride, polyvinyl alcohol, styrene, polypropylene, polyester, formaldehyde, styrene acrylonitrile copolymer, ethylene propylene copolymer. Environmental protection industry: electroplating wastewater sludge, boiler ash, pharmaceutical factory waste, sugar factory waste, monosodium glutamate factory waste, 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, biological sludge. Food industry: starch, cocoa beans, corn kernels, salt, modified starch, pharmaceuticals.
Chemical industry: Soda ash, nitrogen phosphorus potassium compound fertilizer, kaolin, bentonite, white carbon black, carbon black, phosphogypsum, sodium fluoride oxide, calcium nitrate, magnesium carbonate, sodium cyanide, aluminum hydroxide, barium sulfate, calcium sulfate, calcium carbonate, dyes, molecular sieves, saponins.