Cyclone parameter adjustment
Writer： admin Time：2020-08-17 11:13 Browse：℃
The hydrocyclone is an effective separation device that uses centrifugal force field to separate two-phase fluids. It is a non-moving separation device composed of an upper cylinder and a lower cone. The principle is that after the slurry is injected into the barrel from the feeding tube in a tangential, involute or spiral manner, the mixture of medium and particles rotates to form a centrifugal force field, and particles (or liquid phase) of different sizes and densities are generated Different trajectories, under the action of centrifugal force, medium resistance and other force fields, coarse particles and high-density particles move to the periphery and are discharged from the grit through the cone; fine particles and low-density particles (or liquid phase) It moves to the center and is discharged by the overflow pipe, and finally realizes the separation of the coarse and finely divided solid particles and fluids of different densities.
Cyclone is a widely used heterogeneous phase mixture classification equipment. Its basic principle is to subject liquid-liquid, liquid-solid, liquid-gas and other two-phase or multi-phase mixtures with a certain density difference under the action of centrifugal force. Separation. The oil-removing hydrocyclone is a hydrocyclone that uses the density difference between oil and water to separate oil-water from oily wastewater under centrifugal force. Compared with traditional oilfield oily wastewater treatment equipment, it has a small volume and light weight , Simple operation and high efficiency.
The oily sewage enters the swirling cavity through the radially distributed elliptical hole entrance of the hydrocyclone, and is guided by the guiding swirling device in the swirling cavity to produce high-speed rotation. Under the action of the swirling centrifugal force, the water phase of the oily sewage is centrifuged Settling, swirling along the wall of the tapered tube facing the underflow port, and discharged at the underflow port; the oil phase with low density migrates to the middle, swirling along the axis to the overflow port, and discharged at the overflow port, completing the separation of oil and water in the tapered tube.
Cyclone adjustment parameters:
The diameter of the cylindrical cylinder is the main criterion for distinguishing the size of the hydrocyclone, and there is a certain proportional relationship with the size of other parts. Increasing the diameter of the cylindrical cylinder can improve the processing capacity of the hydrocyclone, but at the same time the overflow particle size will become coarser, and vice versa. When processing fine-grained materials and the processing volume is relatively large, we can use multiple small cyclones in parallel to form a group.
The height of the cylindrical barrel has a significant impact on the residence time and classification efficiency of the slurry in the cyclone. When the insertion depth of the overflow pipe is constant, increasing the height of the cylinder will extend the separation time, reduce the separation particle size and improve the separation efficiency, but it also has the negative effect of reducing the output and increasing the energy consumption. When the height of the cylinder is reduced, you will get the opposite result. Generally, when the height of the cylindrical barrel is 0.6-1.0 times the diameter of the cylindrical barrel, the effect is better.
To mine mouth diameter
Generally, the diameter of the feed port is 0.13-0.25 times the diameter of the cyclone. Appropriately increasing the feed port diameter can increase the throughput of the cyclone, but at the same time the classification efficiency will be reduced. Generally, the cross-sectional shape of the hydrocyclone feeding pipe is mostly circular and rectangular, and most of them are rectangular. The configuration is mostly such that the long side is parallel to the cyclone axis, and the short side is perpendicular to the cyclone axis.
In the early days, the structure of the feed pipe and the connection with the barrel were mostly tangential. Its advantages are simple structure and convenient configuration, but the flow pattern changes suddenly, and the resistance loss along the way is large, which is easy to produce turbulence. Later, involute feed pipes were generally used, which had the effect of reducing energy consumption, increasing production capacity and improving separation efficiency.
Overflow pipe diameter
overflow pipes are mostly circular, and their diameter is usually 0.2-0.3 times the diameter of the hydrocyclone. Its main function is to smoothly, constantly and continuously lead the separated overflow product out of the body. Increasing the diameter of the overflow pipe will increase the overflow flow, but the overflow particle size will also become thicker, and the fine particles in the sedimentation will decrease and the concentration will increase.
Grit port diameter
Generally, the diameter of the grit port increases, the overflow flow decreases, and the overflow fineness becomes finer, while the amount of grit increases, the concentration decreases, and the fineness increases, but it has no significant effect on the throughput of the cyclone. The diameter of the grit port If it becomes smaller, the amount of sediment discharged will decrease, and the phenomenon of "roughening" will appear in the overflow. If it is too small, the coarse particles will accumulate more and more on the top of the cone, resulting in blockage.
Under normal circumstances, the diameter of the grit port should ensure that the grit is discharged in an umbrella shape, and the ideal angle is 20°-30°. The diameter of the grit port is usually 0.07-0.1 times the diameter of the overflow pipe.
overflow pipe insertion depth
If the overflow pipe is inserted too shallowly, the short-circuit flow will increase, the separation time will be shortened, the content of coarse particles in the overflow product will increase, and the content of fine particles in the sedimentation product will increase, and the classification efficiency will decrease; if the overflow pipe is inserted too deep , The bottom coarse-grained grade will enter the overflow, reducing the classification efficiency of the hydrocyclone. In general, the insertion depth of the overflow pipe should be 0.5-0.8 times the height of the cylinder.
The cone angle of the cylindrical barrel
Increasing the cone angle of the cylindrical barrel will reduce the height of the cyclone and increase the average radial velocity of the slurry. At the same time, due to the increase of the blocking effect of the cone, the upward velocity of the slurry will also increase, resulting in a coarser overflow particle size. Therefore, when separating coarse-grained particles, a large cone angle (30°-60°) is recommended; when separating fine-grained particles, a small cone angle (15°-30°) is recommended; and a smaller cone angle (15°-30°) is recommended for desilting. The cone angle (10°-15°).
pressure to mine
The feed pressure has a direct effect on the throughput and separation particle size of the cyclone. Generally, the pressure of the mine should be maintained at 49-157kPa. Increasing the feed pressure can reduce the classification particle size and increase the processing capacity, but at the same time it will also significantly increase the power consumption and cyclone wear. When working normally, the feed pressure of the hydrocyclone should maintain a stable value.
Pulp properties
The properties of slurry mainly include density, particle size and slurry concentration. In the case of the same slurry concentration, the greater the ore density, the finer the grading particle size.
When the slurry concentration is higher and the mud content is higher, the viscosity and density of the slurry will increase accordingly, which increases the resistance to the movement of the particle size and makes the classification particle size coarser. vice versa. The ideal slurry concentration should be determined by the beneficiation test according to the specific production situation.
