Desander is called hydrocyclone desander strictly. It’s same working principle with desilter separator. In mud cleaning system, it is usually set behind shale shaker or vacuum degasser.
Desander function in mud cleaning system
For drilling fluid cleaning or purification, the hydrocyclone desander and desilter must be configured with numbers of cones. And to make sure their effective performance, the working pressure must be 0.25~0.35MPa.
De-sander hydrocyclone includes 8″, 10″ and 12″. According to our former figure and theory, the capacity is 176GPM, 440GPM, 500GPM accordingly. While the separation points are 30microns, 36um, 50 microns accordingly. Of course this cut point is as per API D50.
We can find, the desander’s main function is to get rid of larger particles after shale shaker but before desilter. Means hydrocyclone desander will leave better fluid property for desilter cones. The main separation range is 40-70microns.
How select desander for mud cleaning system?
Select proper hydrocyclone desander for whole mud cleaning system we must consider the mud pump maximum flow rate. Usually, we configure desander its capacity should be same as the mud pump max discharge rate or even 125% of mud pump maximum flow rate.
For example, at oilfield drilling site, the oil drilling mud pump discharge capacity is 528GPM, then our hydrocyclone desander should be selected as 528GPM~660GPM. Meanwhile, the desander feeding pump should be also 528GPM~660GPM. At this time, the desander separator is configured with three 8″ desander cones.
Requirements on mud cleaning desander
Firstly, we should confirm there is no broken, leakage, or block on desander cones. All pipelines are clear, valves are at correct position, mounted steadily and reliably. Then, confirm feeding pump is all right for operation.
Before desander working, switch on mud gun, agitator, make feeding pump inlet clean then operate desander pump and desander. During operation we need to check the pressure gauge on desander feed inline.
The figure should be 0.2~0.4MPa. This pressure range is correct can ensure desander safe and effective performance. The drilling fluid out of drop in Apex appears like umbrella. There is 0.4g /cm3-0.8g /cm3 margin between top overflow fluid and bottom fluid density. All sealing parts hold be sealed without any space or leakage
To be noted, before we stop feeding pump, must close desander feed inline. After drilling fluid discharged completely in desander cone, then we can stop the centrifugal pump. Usually, desander and desilter will work together. Importantly, there must be 2 separated single pumps for each equipment or separator.
Furthermore, if we feed foam beater or other additive we can’t use desander continuously. Anyhow, we should operate and maintain the mud cleaning desander according to user manual.
If you are in the demand on desander, please contact us freely. Other mud cleaning equipments are also available for you.