An automated and compact multiphase flow meter (MPFM) tested offshore Saudi Arabia has accurately measured three-phase flow rates under existing field operating flow conditions. A three-month field test was conducted utilizing over 160 well tests under varying operating conditions. A meter was installed on an offshore test barge, so that individual wells could be tested in series with traditional test separator methods. For these trial tests, the total liquid rate ranged from about 335 to 12, 333 barrels per day, the GOR ranged from about 67–185 SCF/STB and the water cut ranged from 0 to 70%. The results show that over 93% of the well tests were within +/- 10% of test barge results for all liquid, oil and water cut measurements. While gas measurements were determined to be within +/- 15% in 63% of the wells tests. Also, the results for the gas measurement comparison are discussed although the gas measurements were evaluated against historical field PVT data, due to the unavailability of a valid test barge gas rate comparison meter. The project platforms currently identified for multiphase metering differ in physical size and vary from single well to 8 well configurations. For accurate reservoir management, each well is individually rate tested to monitor well performance and to provide data for field allocation and planning purposes. The wells are presently being evaluated by test barges, which are equipped with testing facilities. A multi-phase flow meter was successfully field-tested as an alternative to the use of the test barges. Permanent multiphase flow meter installations will provide more frequent tests and considerable economical savings in the long run. Introduction The Safaniya Field, which is the largest offshore oil field in the world, has 146 existing offshore platforms. These platforms differ in physical size and vary from single well to 8 well configurations. For accurate reservoir management, each well is individually rate tested to monitor well performance and to provide data for field allocation and planning purposes. The wells are presently being tested by two barges, which are equipped with testing facilities. These barges are approaching obsolescence and require extensive maintenance to maintain the current testing schedule. In addition, numerous offshore platforms are located in areas that are inaccessible to the barges and cannot be easily tested. The barges are also prevented from testing wells approximately one third (1/3) of the time each year due to adverse weather conditions. Furthermore, well testing requirements for the Safaniya field are increasing dramatically due to higher water cuts as the field matures, more wells being drilled, and fluctuations in the field production requirements. It is projected that by 2007, the field will require at least three new test barges to maintain the current testing standards. As a result of the inefficiency and limitations of the test barges, a couple of multiphase meters have been successfully field tested as an option instead of ongoing use of the test barges. Multiphase flow meters will provide the Safaniya field with more frequent tests and considerable economical savings in the long run. Meter Description The PhaseWatcher multiphase meter trial tested in Safaniya field is the latest multiphase flow meter being offered by Schlumberger. This meter measures oil, gas and water rates without separation of the production stream, and calculates flow rates for actual and standard conditions. The portable meter is a compact unit [1.5 meters × 1.6 meters × 1.7 meters] consisting of a typical venturi section with upward vertical flow. In addition, a dual energy gamma ray meter is utilized at the throat of the venturi for measuring oil, water, and gas fractions. Dual Energy Gamma Fraction Meter Calculations of oil, water and gas fractions are based on the attenuation of two different gamma energy levels of a radioactive isotope. The gamma ray contains different energy levels, and the attenuation of two of these energy levels can, by physical equations be expressed as a function of oil, water and gas volume fraction.

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An automated and compact multiphase flow meter (MPFM) tested offshore Saudi Arabia has accurately measured three-phase flow rates under existing field operating flow conditions. An extensive eight-month field test in the Safaniya field was conducted from October 1999 to June 2000 utilizing over 350 well tests under varying operating conditions. A meter was installed on an offshore test barge, so that individual wells could be tested in series with traditional test barge methods. For these trial tests, the total liquid rate ranged from 1300 to 12000 barrels per day, the GOR ranged from 150 to 350 SCF/STB and the water cut ranged from 0 to 50%. The results show that over 90% of the wells tested were within +/- 10% of test barge results for all liquid, oil and water cut measurements. While gas measurements were determined to be within +/- 15% in 75% of the wells tested. As a result of this favorable field test and other economic considerations, a multiphase flow meter is recommended for installation on all Safaniya Field existing offshore platforms. Project installation designs for the first five meters have been completed and plans are being made to install them beginning in early 2002. Introduction The Safaniya Field, which is the largest offshore oil field in the world, has a wide variety of offshore platforms. These platforms differ in physical size and vary from single well to eight-well configurations. For accurate reservoir management, each well is individually rate tested to monitor well performance and to provide data for field allocation and planning purposes. The wells are presently being tested by two barges, which are equipped with testing facilities. These barges are approaching obsolescence and require extensive maintenance to maintain the current testing schedule. In addition, numerous offshore platforms are located in areas that are inaccessible to the barges and cannot be easily tested. The barges are also prevented from testing wells approximately one third (1/3) of the time each year due to adverse weather conditions. Furthermore, well testing requirements for the Safaniya field are increasing dramatically due to higher water cuts as the field matures, more wells being drilled, and fluctuations in the field production requirements. As a result of the inefficiency and limitations of the test barges, a multi-phase flow meter was successfully field-tested as an alternative to the use of the test barges. Multiphase flow meters will provide the Safaniya field with more frequent tests and considerable economical savings in the long run. Meter Description The Fluenta multiphase meter 1900VI trial tested in Safaniya field is the latest multiphase flow meter produced by Roxar in Norway. This meter measures oil, gas and water rates without separation of the production stream, and calculates flow rates for actual and standard conditions. The multiphase meter determines oil, gas and water fractions from the capacitance, inductance readings and gamma densitometer measurements. Each component's velocity, or mass flow rate, is determined from cross correlation or venturi measurements. There are five main components to the MPFM:Capacitance sensor;Inductance sensor;Venturi;Gamma densitometer; andPressure and temperature sensors (see Fig. 1). A detailed discussion of each meter component and underlying operating principles can be obtained from the vendor, if interested.

Shell has used BFS cements on over 160 oil well cementing operations as part of an effort to develop end expand the understanding of blast furnace slag (BFS)-based cements. Well types include major deepwater development wells to sidetracks drilled with a workover rig. Downhole conditions range from cold deepwater applications to shallow thermal wells subjected to cyclic steam injection.To date, the field performance of slag-based cement has met or exceeded expectations. Formation integrity tests, bond logs, and production data indicate good annular isolation. Caaingshoe integrity test datafrom exploratory and development wells showa lower incidence of remedial squeezing prior to drilling ahead es compared to Portland cements. Contrary to previously reported bond-log evaluations, conducted under laboratory conditions, downhole bond logs under saturated conditions indicate an improved caeinglcement bond with time. Production data from wells with dual comoletirms indicate mod mnnl iw-dnt.innhot.wamperforated intervals. Leak-offtestdatafor slag-based cementjobs conducted in the Gulf of Mexico are reported for each casing size. Field data for squeeze cementing casing shoes, liner tops, and casing annuli are also presented.

Challenges associated in developing mature offshore fields of Saudi Arabia require the optimal integration of best reservoir management practices. Such complicated fields require effective collaboration between reservoir engineers and geoscientists for the application of latest technologies and best practices. A variety of practices were implemented to achieve significant improvements in drilling and completing horizontal wells. Some of these challenges have been addressed with the installation of over 200 inflow control devices (ICD) which are used to minimize water coning and gas cusping affects. Economic development of these offshore projects have involved the implementation of 20 Smart wells, in conjunction with, intelligent field monitoring that improves surveillance and reduces manpower requirements. Real-time geo-steering practices, advanced logging measurements, and seismic imaging techniques were successfully utilized for well placement of over 100 horizontal wells in a geologically complex sandstone environment. Also discussed are some future fit-for-purpose technologies that are being considered for these offshore field development projects. Introduction The developed offshore fields (M, Z and S) of Saudi Arabia are located in the Arabian Gulf and consist of sandstones, siltstones and shales with minor limestones and coals deposited in a complex, fluvial dominated delta system. The main producing reservoirs consist of massive, clean highly permeable 1-5 Darcy sandstone units interspersed with shales. The primary drive mechanisms for all three fields results from natural aquifer influx with limited support from gas cap expansion in two fields. Table-1 shows some reservoir characteristics and completion type. Historically, all wells drilled in these fields have been free flowed to the surface without any artificial lift. Recently, one of the fields installed a number of electrical submersible pumps (ESPs) to increase well productivity. For other wells that cease to flow at high water cut, a drilling program has been undertaken to convert these vertical wells to horizontal wells with passive inflow control devices (ICDs). Horizontal wells were introduced in the early nineties in all Saudi Arabian offshore fields to sustain production targets. Before 2003, most horizontal wells drilled in the sandstone offshore reservoirs were completed as cemented and perforated liners completions. After 2003, many of the new horizontal wells began using ICDs to improve production profile along the horizontal lateral section. These new completions increase the distance to the oil water contact (OWC), reduce water coning tendencies, and extend the life of the well. Additionally, for those those wells located in fields with a central gas cap dome area, Smart in-situ gas lift technology is available to increase production and further extend well life. The objective of this paper is to share the best reservoir management practices and strategies to meet challenges associated in developing mature offshore fields of Saudi Arabia.