الفهرس 
Chapter One IntroductionOnly 14 pages are availabe for public view
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Abstract
Water production is a longstanding problem that is becoming critical as more and more oil is being displaced by either the underplaying water or waterflooding. Excessive water production causes a decrease in reservoir driving force, decreasing relative permeability to oil. In addition to these; it helps scale to form and encourages sand production. Asphaltene deposition occurs in case of heavy oil, emulsion formation when oil and water are mixed in the flow, corrosion problems associated with water production and creation of environmental hazards for water dumping or disposal. Water shut-off is a method that is used in controlling excessive water production problem which is divided to three ways. The mechanical solution was often the first choice for remedial which includes the usage of bridge plugs, sand plugs, packers, cement and casing patches. The re-completion solution includes two ways one by drilling lateral drain holes that could minimize water conning and the other one is using dual completion which means producing both oil and water separately by dual completion. The chemical solution is the most commonly used technique today as those technologies were applied some distance beyond the wellbore into the formation by means of using inorganic gel, polymer gels, foamed gel and relative permeability modifiers. This study presents an evaluation of the water shut-off techniques that have been made in one of the Egyptian oil fields (Belayim oil field) which started oil production since 1955 under primary recovery mechanism then converted to produce oil under secondary recovery (water flooding) from 1985 up to date. The selected wells for this study are wells #1, #2, #3, #4, #5 and well #6 that were subjected to different ways of identifying water producing zones these wells represents also the major mechanisms used to shut off these zones in Belayim oil field. In well #1 the wells correlation principles were used to identify watered out intervals and isolated them mechanically by bridge plug. In well #2, the watered out intervals were identified by water flow log (WFL) and also isolated them mechanically by bridge plugs. In well #3 the cased hole formation resistivity log (CHFR) were used to identify the watered out intervals and then isolated by cement. In well 4# water zones isolated two times in two different zones and used thermal decay time log in identifying these zones, in the first time isolated watered out zones by cement and in the second time isolated them by bridge plug. Well #5 was treated with polymer as a relative permeability modifier (RPM). Well #6 was subjected to an in-depth treatment called Brightwater that was pumped through an injection well which pops at a distance from oil producing well. Results indicated that, well #1 delivered oil gain 157 CM/D over six months after mechanical water shut-off treatment. Well #2 delivered 12 CM/D over six months after treatment. Well #3 delivered no additional oil gain after mechanical treatment. Well #4 delivered oil gain in the first and second treatments 341 and 178 CM/D. well #5 delivered no oil increase after polymer treatment and well #6 delivered 2895 CM of oil over two years after Brightwater treatment till diverted almost of oil production to another development well. The feasibility study showed that the payout time for mechanical water shut-off methods was one or two days in well #1 and well #4 that got good additional oil but for well #2 the payout time was 36 days due to small amount of oil gain. Well #6 has a payout time of 70 days.