Overview of pneumatic conveying system
Tips: The specific scheme and equipment application need to be professionally customized according to the actual situation of the user! 24-hour technical consultation hotline 0371-64560789! Pneumatic conveying system is
also called pneumatic ash conveying system
, which can be divided into positive pressure pneumatic conveying system and negative pressure pneumatic conveying system, dense phase pneumatic conveying system and dilute phase pneumatic conveying system. Because the pneumatic conveying systems have certain similarities as a whole, the specific pneumatic conveying system should be designed according to the actual situation of the user. Pneumatic conveying can be regarded as a relatively strict conveying system. In fact, both the conveying volume and the conveying distance of pneumatic conveying are closely related to the pressure and air volume. The number of elbows must also be considered. There are many factors such as the caliber of the road, the specific gravity of the material, etc., and then a certain value of pressure and air volume is selected according to these factors, such as pneumatic conveying equipment such as roots fans and air compressors.
First, the negative pressure pneumatic conveying is a conveying system in which the pressure of the entire pipeline is lower than the local pressure when conveying. The pressure suction air flow is a practical, reliable and mature conveying method for the entire air flow. According to the different working pressure, it can be divided into two forms: low vacuum (vacuity less than 1000mm water column) and high vacuum (vacuity less than 1000mm water column).
Second, the positive pressure pneumatic conveying system (also known as the dilute phase positive pressure pneumatic conveying system or air conveying system) uses the airflow output from the blower (such as Roots fan) as the carrier to convey the bulk powder and granular materials into the designated equipment. The powder and granular materials are discharged into the pipeline for pressure feeding by rotating the feeder or the screw feeder. The positive pressure value of the dilute phase positive pressure pneumatic conveying system is less than 0.15Mpa, and the gas-solid ratio is 5 to 20.
3. Dilute phase pneumatic conveying, low pressure, high speed, continuous pneumatic conveying system. It is a pneumatic conveying system that uses Roots blower vacuum pump as the air source to continuously suck and feed materials. The vacuum pump installed at the end of the conveying system is used to suck the air in the system, and a negative pressure air flow is formed in the conveying pipe. The material enters the pipe from the starting nozzle with the atmosphere together with the atmosphere. The effect of gravity or centrifugal force is separated from the air flow, and the gas is discharged into the atmosphere through a centrifugal fan or a vacuum pump after dust removal. It is commonly used for pneumatic conveying of low to medium density non-abrasive bulk solids, where degradation of the conveying material is not a problem. Examples of materials include flour, sugar, salt, grain, malt, and plastic pellets.
Fourth, the dense phase pneumatic conveying system is a dense phase, low pressure, medium speed, continuous pneumatic conveying system. The production process of powder conveying system includes the whole process of mixing all kinds of raw materials through fully automatic batching and corresponding processing to become semi-finished products and finished products. Generally, it is controlled by storage system, conveying system, metering and batching system, mixing system, filling system and central automatic control System composition. Among them, the powder conveying system, the weighing system, and the ingredient mixing system are the main links of production. It is used to transport low-density, heat-sensitive and non-abrasive materials over short distances where high-pressure compressed air is available. Examples of materials that can be delivered include plastic granules, detergent powder, wheat, barley, corn, oats, limestone, coffee beans, granulated sugar, ball clay, and boric acid.
Working principle of pneumatic conveying system
Pneumatic conveying system uses the energy of airflow to convey granular materials in the airflow direction in a closed pipeline, which is a specific application of fluidization technology. Generally speaking, the system has lower infrastructure costs and requires a minimum clearance under the ash hopper. Because its leakage only occurs inside the system, its operation is relatively clean. The pneumatic ash removal system is suitable for the pneumatic ash removal system of small and medium thermal (thermal) power plants (boilers supporting 200MW and below units). The dry ash transportation distance equivalent is 300 meters in length. When the height is 90 meters and the system throughput is below 100t / h, the system has the best cost performance. This system is a low positive pressure dilute phase conveying system.
Dry ash from the dust hopper of the electric precipitator (or bag precipitator) enters the buffer bin and the continuous delivery pump through the ash drop pipe, and uses the Roots blower as the air source (pressure below 98KPa), and is transported to the ash conveying pipe at a certain speed to In the ash warehouse, the gas is discharged into the atmosphere after being separated from the material through a baghouse. There are two ways of dry ash unloading in the ash storehouse (car bulk loader) and wet discharge (humidity mixer). Users can choose according to the use of fly ash.
Fucheng Pneumatic Conveying System is a fully-enclosed pipeline conveying system; flexible layout; no secondary pollution; high efficiency and energy saving; convenient for material transportation and recovery, non-leakage transportation, computer control, high degree of automation, stable operation, safe and reliable There is a pipe blocking phenomenon; using Roots fan as the air source, the reliability of Roots fan also determines the reliability of the system. In addition, the pneumatic ash removal system designed by Fucheng has a simple process, maintenance-free, fewer equipment parts, no frequent actions, very few failure rates, and almost no wearing parts. Continuous low-pressure conveying, low and constant flow velocity in the tube, so little wear. Low energy consumption, low operating costs, and comprehensive investment savings. The system is equipped with low-pressure roots blowers, which saves energy by more than 20% compared with the warehouse pump system, saves operating costs by more than 50% compared with the warehouse pump system, and saves more than 30% in overall investment compared with the warehouse pump system.
Optional components of pneumatic conveying system:
Feeding device: sealing pump, air lock valve, feeding valve, electric feeder
Air supply device: air compressor, roots fan, centrifugal fan, dryer, gas storage tank, pressure regulator
Piping: straight pipe, wear-resistant elbow, roof pipe, pipeline switching valve, expansion joint
Gas separator: cyclone separator, bag filter
Instrumentation and control system: pressure transmitter, level gauge, pressure switch, local control cabinet, PLC
Gongyi Fucheng Machinery Factory is a professional manufacturer of pneumatic ash removal systems. From the design and development of the entire pneumatic conveying system to the production and installation of pneumatic conveying equipment, it is all solved by itself. No other suppliers in the middle. And Fucheng Machinery's efficient after-sales service is your best choice!