Scale Deposition in Surface and Subsurface Production Equipment in the Gulf of Suez

Abstract

Abstract Generally the deposition of oilfield scale in surface and subsurface production equipment can cause many operational problems. Scale precipitation in oilfields has a detrimental effect on fluids, processing equipment, pipelines, and downhole well equipment processing equipment, pipelines, and downhole well equipment as a result of Corrosion and flow restriction. Scale deposits in wellbores can result in severe production loss. Generally scale problems become more prevalent as oil and gas reserves are depleted and water production increases. production increases. Some of the Gulf of Suez oilfields, El Morgan, July, and Ramadan, have been waterflooded by the Gulf of Suez sea water. Compatibility tests have indicated probable deposition of scale on surface and probable deposition of scale on surface and subsurface production equipment. Case histories relating to scale deposition, removal and inhibition in surface equipment are discussed. The paper outlines the physical and theoretical prediction for downhole physical and theoretical prediction for downhole scale deposition in oil wells. The experience with scale removal and inhibition by the formation squeeze treatment technique is presented along with recommendations that can be applied to similar cases in other fields in the Gulf of Suez. Introduction The deposition of oilfield scale in surface and subsurface oil and gas production equipment has been recognized to be a major operational problem. The negative consequences of scale contribute to equipment wear and corrosion and flow restriction thus resulting in production decrease. Experience in the oil industry has indicated that many wells have suffered flow restrictions due to scale deposition within the formation, the well bore region, perforations, and tubing strings. Scale deposits in surface production equipment amplify these problems. Oilfield scale costs much in terms of production losses, frequent pulling jobs, reperforations, redrilling and reaming, stimulation, and other similar remedial workovers. It is estimated that many wells in the U.S.A. have reduced production due to scale deposits in the formation and wellbore and that many oil producers and formations have been prematurely abandoned due to plugging by scale deposits. prematurely abandoned due to plugging by scale deposits. In the literature many case histories regarding the oilfield scale problem have been reported. Cowan et al have stated cases for calcium carbonate scale deposition in surface production equipment, in Mexico, South and West Texas, and North and South Louisiana oilfields. P. 93