Pump head used in dry desulfurization process

Plastic pump heads are currently widely used in industrial environmental protection equipment. Desulfurization technology refers to the removal of sulfur oxides (SO2 and SO3) from flue gas or other industrial waste gases.

 

Desulfurization technology is divided into dry desulfurization technology, semi-dry desulfurization technology and wet desulfurization technology. Different desulfurization technologies use different nozzle methods. The material transported in the dry desulfurization technology is desulfurization agent powder, usually using air flow nozzles. In the semi-dry desulfurization technology, limestone slurry is transported with high concentration and high viscosity, and air-flow nozzles are usually used. The research shows that the airflow mass ratio and concentration are the main parameters affecting the uniform droplet particle size. The increase of the gas-liquid mass ratio leads to a decrease in the uniform SMD of the droplets; the increase of the concentration increases the SMD.

 

In the wet desulfurization technology, the nozzles are usually used for scrubbing the flue gas of the desulfurization scrubbing tower, cleaning the demister blades, etc. The diameter of the spray droplets required by the technology is usually 1300-3000 μm, and considering factors such as energy consumption and pump head conflict, Pressure-type pump heads are often used. Regarding the pressure pump head selected in the wet flue gas desulfurization technology, the simpler the components that make the liquid rotate, the better, and because the required atomization particle size is larger, the rotary pressure pump head is usually selected. Most of the pump head inlets are one, which is tangent to the rotating chamber. The slurry enters the rotating chamber from the tangential inlet to obtain a rotating motion, and then according to the law of conservation of rotational momentum, the rotational speed is inversely proportional to the rotational radius. As the slurry moves towards the outlet of the pump head, the rotation speed increases rapidly, the static pressure energy of the slurry is converted into kinetic energy, and the slurry rotates around the air core to be ejected to obtain a hollow cone pump head.

 

On the basis of summarizing economy and characteristics, the commonly used pressure pump heads in desulfurization technology mainly include solid cone swirl pump head, hollow cone swirl pump head, air cone screw pump head and solid cone screw pump head. Among them, the use of hollow cone swirl pump heads is the most common.

 

Because the position of the pump head in the wet desulfurization technology determines the importance of the research on the pump head, with the advancement of the technical research, the research on the pump head is gradually deepened. Yao Zengquan, a domestic expert, started from the ideal fluid, and through the correction of turbulent resistance, deduced a series of relational expressions followed by the simple swirl pump head, and gave the calculation method of each parameter of the simple swirl pump head. The viscosity correction in the method still needs to be discussed. .

 

At present, there are still few researches on the use of the pressure pump head with limestone slurry as the medium, and the research is usually carried out with water as the medium. The research on the internal and external flow field layout of the pump head and the placement method of the pump head inside the spray tower is rarely touched.

 

All in all, as far as the pressure pump head is concerned, its research has been carried out for more than 100 years, and a relatively complete theoretical system has been formed. However, there are relatively few pump head studies related to desulfurization technology. At present, China still cannot develop the pump head of the scrubber by itself, and the need for localization is very urgent. Therefore, it is of great significance to study the system theory and application of pump heads commonly used in desulfurization technology, imitate internal and external flow fields, establish models, study pump head design, and conjecture the diameter of atomization, drawing on the experience of predecessors. At present, most of the plastic pump heads are mainly used in China.