Cyclone dust collector

The cyclone is composed of air inlet pipe, air outlet pipe, cylinder body, cone body and ash bucket. Cyclone dust collector has simple structure, easy to manufacture, install and maintain, and the equipment investment and operating costs are lower. It has been widely used to separate solid and liquid particles from gas streams or to separate solid particles from liquids. Under normal operating conditions, the centrifugal force acting on the particles is 5 - 2500 times that of gravity, so the efficiency of the cyclone dust collector is significantly higher than that of the gravity sedimentation chamber. Based on this principle, a cyclone dust removal device with dust removal efficiency of more than 90% has been successfully developed. In mechanical dust collectors, cyclone dust collectors are the most efficient. It is suitable for the removal of non-viscous and non-fibrous dust, mostly used to remove particles above 5μm. The parallel multi-cyclone dust collector device also has a dust removal efficiency of 80-85% for 3μm particles. Cyclone dust collectors manufactured of special metal or ceramic materials resistant to high temperature, abrasion and corrosion can be operated at temperatures up to 1000 °C and under pressure up to 500 × 105 Pa. From the aspects of technology and economy, the control range of cyclone dust collector pressure loss is generally 500-2000Pa. Therefore, it is a medium-efficiency dust collector and can be used for purifying high-temperature flue gas. It is a widely used dust collector and mainly used in boiler flue gas dedusting, multi-stage dust removal and pre-dusting. Its main disadvantage is the low removal efficiency of fine dust particles (<5μm).

Cyclone dust collector advantages：

 According to the method above of integrating the axial velocity on the flow area, the change of the descending flow rate after the installation of different types of drag reducing rods in the conventional cyclone dust collector is calculated together, and the downward flow rate at different sections in various cases accounts for the total treatment flow of the dust collector. The percentage is plotted to indicate the difference between the average flow rate of the upstream and downstream flow zones, that is the downward flow, and the actual overflow rate of the upstream and downstream flow zones. It can be seen that the short-circuit flow and the descending flow of each model vary along the height of the dust collector. Compared with the conventional cyclone dust collector, the short-circuit flow is increased after the full-length drag reducing rods 1# and 4# are installed, but the short-circuit flow is reduced after the non-full-length reducing rods H1 and H2 are installed. After the installation of 1# and 4#, the variation of the downward flow along the flow path is basically the same as that of the conventional cyclone, showing a linear distribution, and the three lines descend nearly in parallel. However, after installing H1 and H2, the distribution is a fold line instead of a straight line, and the inflection point is just the position of the section where the drag reduction rod is inserted from the bottom to the top. It can also be seen that the non-full-length drag reduction rod increases the downward flow rate of each section above the section, and the downward flow rate is larger than that of the conventional dust collector. However, after contacting the drag reduction rod, the downward flow rate decreases rapidly, reached or lower than the value of a conventional dust collector at the bottom of the cone body.

The reduction of the short-circuit flow rate can improve the dust removal efficiency, increase the downward flow rate of the section, and increase the residence time of the dust-containing air in the dust collector, creating more separation opportunities for the dust. Therefore, although the non-full-length drag reduction rod is not as effective as the full-length drag reduction rod, it is more conducive to improving the dust removal efficiency of the cyclone. There is a short-circuit flow of up to 24% near the inlet section of the exhaust core of the conventional cyclone dust collector, which will seriously affect the overall dust removal effect. How to reduce this part of short-circuit flow will be a research direction to improve efficiency. Although the drag reduction effect of the non-full-length drag reduction rod is not as good as that of the full-length drag reduction rod, it will be more effective because it reduces the short-circuit flow of the conventional cyclone dust collector and increases the cross-section flow rate, so that the dust removal efficiency of the cyclone dust collector is improved, which is of more practical significance.

Cyclone dust collector classification:

• High-efficiency cyclone dust collector, the cylinder diameter is small, used to separate fine dust, the dust removal efficiency is above 95%;
• Large-flow cyclone dust collector with large cylinder diameter for handling large gas flow, and its dust removal efficiency is 50-80%;
• General-purpose cyclone dust collector, the air volume is moderate, due to different structural forms, the dust removal efficiency varies between 70-85%.
• Explosion-proof cyclone dust collector, with its own explosion-proof valve, with explosion-proof function.

According to the structure form, it can be divided into the long cone, the cylinder, the diffusion type, and bypass type.

According to the combination and installation conditions, it is divided into internal cyclone dust collector, external cyclone dust collector, vertical and horizontal type, and single cylinder and multi-tube cyclone dust collector.

According to the introduction of airflow, the flow path of the airflow into the cyclone and the secondary air can be generally divided into the following two types:

• Shear flow cyclone dust collector
• Axial cyclone dust collector