Successful Gas Shut Off Using Latest Gel Technology In An Indian Offshore Carbonate Field - A Case Study.

摘要

The offshore-A oil field is located in the Arabian Sea to thernwest of Mumbai India & is operated by ONGC under Assetrnbased management system. The field is a saturated reservoirrnwith three small gas caps & is under production with pressurernmaintenance by peripheral water injection. Some of the wellsrnfalling near to the gas cap produce with high GOR due to gasrnconing or cusping. Several efforts made to control the high gasrnproduction by conventional cement squeeze technique did notrnproduce any result. As a result the wells were either closed orrnunder production sub-optimally with a low choke size.rnThe low recovery from the area due to closure of the highrnGOR wells & unsuccessful attempt of cement squeeze jobs forrnGas shut off warranted ONGC to search for new technology torncontrol the high gas production with a deep penetration newrngel technology.rnAccordingly the gas control jobs were carried out in two wellsrnafter an extensive study on reservoir characteristics, selectingrnbest candidate wells & right type of polymer gel, involvingrnlaboratory studies to see the compatibility of the gel with therncore & formation fluids and using proper gel placementrntechnique. This integrated approach with a multidisciplinaryrnteam effort was adopted for the first time under the asset basedrnmanagement system.rnThe post treatment production data showed significantrnreduction in total gas production along with substantialrnincrease in oil production which indicates that the gasrnproduction from the gas cap has been blocked successfully byrnthis treatment.rnThe paper deals in detail the integrated team approach adoptedrnin the Asset team for a reservoir focussed conformancernsolution to improve the recovery which led to a success andrnhas opened up a new era in the gel technology for gas shut offrnin carbonate reservoirs in Indian offshore fields.