Roots blower is a kind of double rotor compressor. The axes of the two rotors are parallel to each other. The rotors are composed of impellers and shafts. There is a small gap between impellers, impellers, casings and wallboards to avoid contact and friction. The two rotors are driven by the motor through a pair of synchronous gears and rotate at the same speed in reverse direction. With the meshing of the two impellers, the impeller and the casing and the wall plate are enclosed into a closed air chamber, the size of which does not change during the rotation process. The compression of the gas is realized by the high pressure gas flowing back to the volume of the basic unit and equalizing the pressure at the moment when the gas chamber is connected with the exhaust port.
1. Roots blower main features:
(1) It has forced conveying characteristics. At a certain speed, the flow rate is basically the same. Even in the small flow area, there is no surge phenomenon like centrifugal fan, which has stable working characteristics;
(2) As a rotary machine, there is no reciprocating mechanism, no air valve, less vulnerable parts and long service life;
(3) There are many times of suction and exhaust in one week of operation. Compared with the piston compressor, the air flow speed is uniform and there is no air storage tank;
(4) There is a certain gap between the moving parts and the static parts, and there is no need for lubricating oil in the chamber, so as to ensure that there is no oil in the conveying gas and no need for oil-gas separation device;
(5) No internal compression process, high mechanical efficiency.
2. According to the use system, roots blower can be divided into gas transmission and pneumatic transmission:
(1) Gas transportation refers to the pressurized transportation of gas to provide (extract) corresponding gas for the physical and chemical reactions in the system. It can meet the pressure transportation of air, nitrogen, oxygen, hydrogen, gas, biogas, steam, carbon monoxide, carbon dioxide, hydrogen sulfide, methane, ethane and other gases.
(2) Pneumatic conveying is a way of conveying solid particles by means of gas flow. As a low-pressure gas source, roots blower is mainly used for dilute phase transportation of bulk materials, such as flour, cement, coal powder, coal ash, grain particles, polyethylene, potassium chloride, alkali powder and other powder particles.
3. Roots blower can be divided into the following categories according to the application fields:
(1) In building materials industry, it is used for feeding coal to cement kiln, atomizing fuel oil to kiln burner, homogenizing raw cement, blending coal and homogenizing cement, unloading warehouse and ship, etc.
(2) In the power industry, it is used for flue gas desulfurization and oxidation, dust removal and pneumatic conveying, ash silo gasification, etc.
(3) In the chemical and petroleum industries, it is used for the preparation and desulfurization of synthetic ammonia raw materials, the refining of coke oven gas, the production of sulfuric acid from pyrite and smelting flue gas, the recovery of low-pressure gas, and the vacuum decarbonization of alkali plants.
(4) In environmental protection industry, it is used for sewage aeration, filter backwash, etc.
(5) In the air separation industry, it is used to produce oxygen and nitrogen by PSA in low pressure area.
(6) In other industries, it is used for food vacuum packaging, blister packaging, material drying, aquaculture, grain suction machine, electroplating solution mixing, etc.
Roots blower application case :