Overview of blade sludge dryer equipment
With the increasing awareness of environmental protection among enterprises, sludge is a common problem that hinders their development. Baide Drying has introduced advanced sludge drying technology from abroad and designed a specialized sludge dryer based on the actual situation in China. It can fully meet the requirements of industry customers and has gained the trust and cooperation of more and more enterprises. We have cooperated with more than 50 large, medium and small enterprises in China. Our company will use exquisite technology to better serve you, work together, and create a green land.
Baide Drying specializes in designing and manufacturing paddle type sludge dryers for industries such as printing and dyeing, papermaking, biotechnology, electroplating, thermoelectric, chemical, and wastewater treatment plants. After dehydration, the initial moisture content of general sludge is 80%, and the final moisture content after drying is 10% to 50%. The general sludge requirement is around 30%. Dry sludge can be mixed with coal powder and directly enter the boiler for combustion. The calorific value of sludge is about 1500-2000kcal, which can be used as waste and save energy. Some sludge can also be made into fertilizers and building materials after drying, or directly buried without causing secondary pollution, turning waste into treasure and fully meeting environmental protection requirements. This equipment has low energy consumption, and the heat source can be heated by steam, thermal oil, hot air, flue gas, etc. (evaporating 1kg of water consumes 1.1-1.3kg of steam). It has the advantages of low power consumption, smooth operation, low noise, and small labor consumption. It is basically fully automatic. Production.

Working principle of paddle sludge dryer
The paddle sludge dryer uses steam, hot water, or thermal oil as the heating medium, and the shaft end is equipped with a rotating joint for introducing and exporting the heat medium. The heating medium is divided into two paths, which enter the jacket of the dryer body and the inner cavity of the blade shaft, respectively. The body and blade shaft are heated simultaneously, and the sludge is heated and dried by conduction heating. The dried sludge is quantitatively and continuously fed into the feeding port of the dryer by the screw feeder. The sludge enters behind the dryer and is flipped and stirred by the rotation of the blades, constantly updating the heating interface. It comes into contact with the body and blades and is fully heated, causing the surface moisture contained in the sludge to evaporate. At the same time, the sludge is transported in a spiral trajectory towards the discharge port by the rotation of the blade shaft, and continues to stir during transportation to evaporate the water seeping out of the sludge. Finally, the evenly dried sludge is discharged from the discharge outlet.
The application characteristics of closed blade dryer in electroplating sludge drying are mainly reflected in: the thermal efficiency of hollow blade dryer is about 85% to 95%, and in practice, about 1.3kg of saturated steam (T pressure 0.4MPa) is required for 1kg of sludge dewatering. After drying, the sludge still has a calorific value of 1700-2500kcal/kg, which can be mixed and burned with conventional solid fuels such as coal, fully reflecting the principles of energy conservation and circular economy. Specially designed the structure based on the characteristics of electroplating sludge to ensure the lowest energy consumption for sludge drying; Drying sludge through indirect heat exchange methods such as conduction and radiation, without contact with the sludge, does not require the treatment of a large amount of heat medium containing waste gas.

Process Flow Diagram of Paddle Sludge Drying Machine

Performance characteristics of blade sludge dryer
1. Steam does not come into contact with sludge, and can be reused after condensation, fully saving energy;
2. Due to its high torque, the hollow blade dryer can effectively overcome the resistance caused by the plastic stage of sludge, allowing the sludge to dry to a moisture content below 40% without the need for backmixing, reducing the complexity of the system;
3. The hollow blade dryer rotates slowly, with a speed of less than 4 r/min, which can effectively prevent wear on the dryer wall;
4. High heat utilization efficiency. The sludge dryer adopts conduction heating method for heating, and the heat required for drying is not provided by hot gas, reducing the heat loss carried away by hot gas; Due to the compact structure of the equipment and fewer auxiliary devices, the heat dissipation loss is also reduced, and the heat utilization rate can reach 90%;
5. The equipment has a compact structure and occupies a small area. The heat required for drying is mainly provided by many hollow blade walls densely arranged on the hollow shaft, while the heat transfer from the jacket wall only accounts for a small part. So the heat transfer surface of the unit volume equipment is large, which can save the equipment footprint and reduce infrastructure investment;
6. Wedge shaped blades have self-cleaning ability, which can improve the heat transfer effect of the blades. The dispersing force generated by the combined movement of the inclined surface of the rotating blade and the sludge particles or powder layer makes it easy for the sludge attached to the heating slope to be automatically removed, maintaining the efficient heat transfer function of the blade. In addition, due to the reverse rotation of the two shaft blades, the sludge on the inclined surface is alternately compressed in sections (when the inclined surfaces of the two shaft blades are close to each other) and expanded (when the inclined surfaces of the two shaft blades are late), causing the sludge near the heat transfer surface to be vigorously stirred and improving the heat transfer effect.
7. It can adapt to changes in sludge moisture content and has high uniformity in product drying. The dryer is equipped with an overflow weir, and the height of the overflow weir can be adjusted according to the nature of the sludge and drying requirements to regulate the amount of sludge retention in the dryer. It can make the retention of sludge in the dryer reach 70-80% of the cylinder volume, increasing the retention time of sludge. In addition, the feeding speed, shaft rotation speed, and thermal carrier temperature can be adjusted, and the residence time can be arbitrarily selected between minutes and hours. Therefore, the adaptability to changes in sludge moisture content is very extensive.
8. Hollow propeller blades have a crushing and stirring effect on sludge, and the sludge can naturally form particles after drying. Under the stirring effect of the propeller blades, the sludge is thoroughly mixed and evenly dried as it flows from the feeding port to the discharging port in the dryer. Helps to be sent to the fluidized bed boiler for further incineration.

Installation photo of antibiotic residue sludge dryer equipment

Installation photo of electroplating sludge dryer equipment