Study On Structural Optimum And Manufacture Technique Of Inlet For Hydrocyclone

The inlet of liquid-liquid separation hydrocyclone, which serves the liquid to form steady field quickly in the vortex chamber, is the primary passage for the oil/water mixture to enter the vortoil separator. The inlet structure and the level of machining accuracy is one of the key factors which decide the separation and using performance of the liquid-liquid separation hydrocyclone. In order to form steady liquid field rapidly, after the oil/water mixture passing through the entrance, improve the separation efficiency and meanwhile decrease the pressure loss as low as possible at the inlet, this paper has lucubrated the parameter optimum and manufacture technique of the inlet structure.Based on the contrast experiment for the pressure characteristic and separation characteristic on different inlet channel: equal section linear type, gradual change section linear type and curve type, the relation that the inlet structural dimension and operation parameter influence the pressure loss and separation efficiency has been established. These trials show that the pressure loss at the entrance will drop along with the increase of the dimension that is vertical to the tangent of the inlet channel. Increasing the inlet cross section properly can ensure an unobvious drop in the separation efficiency as well as the whole pressure loss decreasing efficiently in hydrocyclone. The inlet structure whose both sides dimension are almost equal makes for decreasing emulsification. Moreover the narrow rectangular inlet channel is more in favor of forming the steady flowing field quickly in the vortex chamber. When the spilt ratio is small, the gradual change section linear inlet has better pressure characteristic and separation characteristic. The involute-curve inlet channel should be selected first as the larger spilt ratio necessarily. These conclusions offer basises for rational design of the inlet structure and its parameter on hydrocyclone.The laser speed-meter is adopted to further analyze the vortex field. The result indicate increasing a certain range of the spilt ratio will somewhat improve the separation effect. Too large spilt ratio, however, will increase the speed grads drastically, which farther aggravate emulsification for the oil drop, enhance the circulation as well and more badly screen effect, and instead may decrease the separation efficiency. Thus, the spilt ratio should be controlled in a reasonable range. As for the deoiling hydrocyclone, the spilt ratio whose value is between 8%~ 10% under trial condition can obtain the optimal separation efficiency. These conclusions will practically guide us to select the operation parameters on hydrocyclone reasonably.The contrast trials for the pressure loss and separation efficiency between the arc-curve inlet channel and the involute-curve inlet channel shows that the arc-curve inlet channel can replace the involute-curve inlet channel. The manufacture study correlative to the inlet structure characters is carried out. The technical ciamp for machining the arc-curve inlet channel is manufactured and can be machined on milling machine. The machining accuracy satisfies the design require in the drawing.