Sand Control in Horizontal Wells in Heavy Oil Reservoirs

Abstract

ABSTRACT Horizontal wells are of great interest to most oil companies operating in heavy oil fields. Due to more extensive contact with the reservoir, horizontal wells allow fluid flow at lower fluid velocities yet providing total flows which are economic. While horizontal wells have the potential to make many more heavy oil reservoirs economic, one of the most pressing concerns has been to be able to complete the wells properly. Unfortunately, likely candidates of horizontal wells are mostly "quicksand" type formations and the critical velocities of sand in a wellbore is extremely low. Consequently, sand is very likely to enter the horizontal wellbore if not preventive measure is taken. Problems of sand production in a horizontal well is more complicated than in a vertical well due to difficulty in cleaning sands in horizontal wellbores. The present study discusses the problems of sand production in a horizontal well and offers recommendation in controlling them. Physical simulation of the top part of the horizontal well showed that both gravitational and inertial forces help minimizing sand production. This will mean that increasing flow rates will decrease sand production. Experimental evidence showed that selection of liner diameter and wire spacing are important parameters in controlling sand productions. Permeability damage due to particle mixing in the annulus was quantified. It was shown that smaller annulus is of more importance in the case of smaller wire spacing, lower oil viscosity and thinner pay zone.