Study On Sand Production Mechanism And Initial Sand Control Technology In Liuquan Oilfield

Liuquan Oilfield is developed with siltstone and fine sandstone reservoir with shallow burial,loose and poor compaction formation.Sanding has seriously affected the normal production of oil and water wells: frequent well washing and pump checking have to be conduct due to payzone plugging and stuck pipe caused by sanding;the surface facility and downhole equipment are excessively abraded;in some severe cases,wells have to be abandoned because of well collapse and casing damage caused by serious sanding.Since 2010,chemical sand control technologies such as coated sand and sand-fixing agent,and cased hole gravel pack have been applied,but all have short duration.Therefore,study on the sanding mechanism to identify the most suitable sand control technology for Liuquan Oilfield is of great significance for improving the field development.Investigation on the current status of sand control technology has been conduct.The reservoir characteristics and development strategy of Liuquan Oilfield have been studied.The causes of sanding have been analyzed from geology and production aspect to identify the sanding mechanism.Well logging data were used to predict sanding.On the basis of sand particle size analysis,the sand control completion method is selected considering the oil and water layer distribution,oil layer span and production requirement.The high pressure gravel pack is preferred as the sand control method.According to the challenges of gravel pack operation in the long horizontal section,the design of the internal and external string of initial sand control and the optimization of operation parameters are conducted.Based on the results of formation sensitivity analysis,the completion fluid system and the sand-carrying liquid system are selected,and the perforation plan is optimized.A comprehensive sand control completion strategy is formed by integrating sand control,sand management and reservoir stimulation.The high-pressure gravel pack sand control technology has been applied in four wells,which successfully addressed the problem of fine sand control of Quan 2 Block and realized the effective recovery of reserves,providing certain reference for the development of similar type of reservoirs.