Pressure Drop in Cyclone Separator

Date: 2021-11-18     From: Longding     Author: admin

The pressure drop in the cyclone separator is the difference between the pressure at the inlet and the pressure at the outlet of the overflow pipe. It is an important parameter of the cyclone, which directly affects the distribution of flow plants inside the cyclone, the movement trajectory of solid particles, and the final separation effect. This article shows the influence of different structural parameters on the pressure drop through the performance test of the cyclone, which is of great significance to improving the performance of the cyclone.

Since only static pressure loss is usually considered, it is assumed that the kinetic energy of the overflow is equal to the kinetic energy of the feed, and the former can be recovered. Therefore, the pressure drop can be used to express the energy loss of the liquid after passing through the cyclone. Ignoring the influence of gravity, it can be seen that the energy loss through the hydrocyclone is: △E ＝ E i – Eo – E u =(1/2pv²i+pi)Q-(1/2pv²o+po)Qo-(1/2pv²u+pu）Qu

Among them, E_i, E_o, E_u represent the energy of the inlet, overflow, and underflow respectively; Q is the production capacity (m³/s); Q_u and Q_o are the underflows and overflow flow (m³/s); p_i, p_o, p_u are the pressure (Pa) at the inlet, overflow and underflow respectively; v_i, v_o, and v_u is the liquid velocity (m/s) at the inlet, overflow, and underflow respectively; p is the density of the liquid (kg/m³).

The influence of structural parameters on pressure drop

When the total area of the outlet remains the same, that is, the sum of the diameter of the overflow port and the diameter of the underflow port is equal, the change of the inlet pressure with the discharge ratio is not obvious. It can be considered that the inlet pressure is mainly related to the total area of the outlet at both ends of the cyclone. However, the pressure drop of the cyclone decreases with the increase of the discharge ratio when the total outlet area is the same. This is because the underflow slurry is mainly solid particles with less liquid content, and the density of the underflow slurry is higher than that of the overflow slurry, so the resistance when the slurry flows in the underflow pipe is relatively large. At the same time, the diameter of the underflow pipe is generally smaller than the diameter of the overflow. Therefore, when the diameter of the underflow pipe increases, the resistance to the discharge of the underflow slurry will decrease, so the pressure drop in the cyclone is also significantly reduced.

In conclusion

1. When the total area of the outlet is the same, the pressure drop of the cyclone decreases with the increase of the discharge ratio.

2. When the diameter of the overflow pipe is the same, the pressure drop of the cyclone decreases with the increase of the diameter of the underflow pipe.

3. When the diameter of the underflow pipe is the same, the pressure drop of the cyclone decreases with the increase of the diameter of the overflow pipe.