Drilling fluid solid control system is to control the harmful solid phase particles in drilling fluid. It forms a reasonable and efficient solid control system establishment by scientific arrangement of solid control equipment , which can remove harmful solid phase particles while retain the useful one. So that it can meet the requirement of drilling technology for drilling fluid performance. Nowadays, the new type of drilling fluid solid control system adopts five levels of solid control, the process is as follows.
The first level of solid control-- remove the large particles.
The drilling fluid returned from the bottom hole circulation contains lots of big cuttings, it will enter into the vibrating screen by the connecting pipe from the mouth of the well to the tank. So that cuttings whose size is larger than 74 centimeter will be sieved from the drilling fluid by the vibrating screen. Than the first level is completed.
The second level of solid control-- remove the gas.
Deaerator is such a dedicated drilling fluid processing equipment to remove the gas intruded into the drilling fluid, it can remove the gas contained in the fluid quickly and effectively. It also plays an important role in recovering the drilling fluid density, preventing potential blowout and avoiding the borehole collapse risk, so it needs to be paid more attention.
The third level of solid control-- remove the relatively larger particles.
The drilling fluid will enter into the desander after being dealt by the vibrating screen. Then the desander will separate the relatively larger particles range from 44 centimeter to 74 centimeter from the drilling fluid. So that the desanding process will be completed and it is just called the third level of solid control.
The fourth level of solid control-- remove the small particles.
The drilling fluid will enter into the desilter after being processed by the desander. Then the desilter will separate the small particles range from 8 centimeter to 44 centimeter from the drilling fluid. So that the desilting process will be completed and it is called the fourth level of solid control.
The final level of solid control-- remove the relatively smaller particles.
The drilling fluid will enter into the centrifuge after being processed by the desilter. Then the centrifuge will separate the relatively smaller particles range from 2 centimeter to 8 centimeter from the drilling fluid. So that the centrifuging process is be completed and it is called the final level of solid control.
This level is mainly used in complex well conditions or well conditions of high demand. During practical use, we can choose several levels or just a certain level of solid control processing according to the different requirements of drilling operations. What’s more, it is worth mentioning that after five levels of solid control, the drilling fluid solid content can completely meet the requirements of domestic drilling operation on the quality of the drilling fluid.