Environmentally Friendly MEG Drilling Fluid System for Horizontal Well of Daqing Oil Field

The conventional oil-based used in horizontal wells of Daqing Oil Field is expensive and not environmentally safe, therefore, a study on Water-based drilling fluids that can give OBM like performance are needed. Through experimentation and comparision with oil-based emulsion drilling fluid, the MEG drilling fluid can stabilize shales by the same mechanism of balanced activity OBM. The MEG drilling fluid system developed in laboratory is tested in Daqing Oil Field. The laboratory experiment and field trial show that the MEG drilling fluid system is stable in rheological property and can effectively carry cuttings and clean wellbore. The lubricity and capacity of borehole stability of MEG drilling fluid system are comparable with OBM, better solid carry capacity. The MEG system is easy to formulate and condition. The MEG system is not poisonous and non-hazardous, the use of this drilling fluid could eliminate cost of oil contaminated drilled cuttings disposal. The MEG system can satisfy the needs of horizontal well of Daqing Oil Field and would be expected to replace the OBM in horizontal well drilling operation.