Calculation method of negative pressure pneumatic conveying system:
1、Development and application of negative pressure pneumatic conveying
As the proportion of bulk material fluidization operations in the production processes of various production departments continues to increase, and rapidly develops toward comprehensive mechanization and automation, pneumatic conveying technology has also been greatly developed. At present, it has been widely used in agriculture, light industry food, tobacco, brewing, textile, wood processing industry, heavy industry in the casting, chemical, rubber, petroleum, mining and other sectors; port, station and warehouse loading and unloading in the transportation industry And in the production department such as construction, there are transportation links and process operations.
2、Working principle of negative pressure pneumatic conveying system
In the pneumatic conveying network, when the fan is working, the inlet section of the fan forms a negative pressure, the outlet section pipe forms a positive pressure, the material is sucked by the fan from the inlet section pipe, and in the inlet section pipe with a certain negative pressure speed. The airflow is delivered to the designated place. This method is negative pressure pneumatic conveying.
3. Characteristics of negative pressure pneumatic conveying
2 Negative pressure pneumatic conveying material is high, the conveying distance is long, and the conveying material line is not restricted by terrain. Compared with the traditional hoist, belt conveyor and positive pressure conveying method, the material conveyed by negative pressure is not raised, and the material conveyed is safe and environmentally friendly. Therefore, the negative pressure pneumatic conveying method is now widely used in the powder transportation of grain, chemical, building materials and other industries.
2 During the transportation process, mixing, classification, pulverization, drying, granulation, etc. can be carried out at the same time, and some chemical reactions can also be carried out.
2 It is safe and reliable to transport unstable chemicals with inert gas.
2 The equipment is simple, compact, flexible in process layout and small in occupancy. It is easy to choose a delivery route.
2 Easy to control and automate the entire system.
4. Design and calculation of negative pressure pneumatic conveying
The calculation of negative pressure pneumatic conveying requires the buyer to provide the maximum output of the material to be transported. The characteristics of the material are the specific gravity of the material, temperature, humidity, particle size and scatter, etc., and the distance and route of the material. The supplier designs the wind network network map based on the information provided by the demand side and calculates the parameters of the wind network. According to the calculation parameters, choose the type of cyclone, fan and pulse bag type dust collector.
5. Comparison of negative pressure pneumatic conveying and positive pressure pneumatic conveying
Negative pressure pneumatic transmission generally adopts large air volume, moderate pressure, and wind pressure is generally around 10000Pa. The centrifugal fan is used as the air source, the material operation is in the negative pressure state, the material is not raised in the blanking operation and the pipeline operation, and the production continuity can be maintained. Sex. Therefore, it does not cause pollution to the production environment and has high production efficiency. Positive pressure pneumatic transmission generally adopts small air volume, high wind pressure, and the wind pressure is generally around 50,000 Pa. The wind network is supplied by a high pressure gas source or by a high pressure blower. The material is in a positive pressure state, and the material is easily leaked at the receiving point and pipeline operation. Therefore, it is easy to cause pollution to the production environment.