Steam Assisted Gravity Drainage = SAGD “Steam-assisted gravity drainage (SAGD; “Sag-D”) is an enhanced oil recovery technology for producing heavy crude oil and bitumen. It is an advanced form of steam stimulation in which a pair of horizontal wells is drilled into the oil reservoir, one a few metres above the other. -wikipedia
The process of drilling oil and gas wells uses a rotary drill bit that is lubricated by drilling fluids or muds. Drilling mud is used to control subsurface pressures, lubricate the drill bit, stabilize the well bore, and carry the cuttings to the surface, among other functions.
The situations in the field are various, which is a challenge in both design and logistics for drilling mud treatment and management. After the core treating process such as solid-liquid separation, it is essential to combine some different operational modules to fulfill the rapid and full handling. The following section will briefly discuss the on-site and off-site treatment/management based on chemical separation according to previous experience.
The use of “dewatering units,” as a regular part of the drilling fluid treatment process on drilling rigs, continues to increase. A dewatering unit, the final phase of a solids control program, is designed to discard no free liquid. A solids control program in which a dewatering unit is used is referred to as a “closed-loop system” (CLS), “sump-less system,” or “chemically enhanced centrifugation” (CEC).