TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractA study from PDO indicated that the allocation and reconciliation factors of Nimr field had shown a deterioration trend since 1999. The suggested possible cause of this deterioration was the increase of net oil calculation uncertainty as water cuts approaches 80% and above. On the individual well basis, about 20% of all the wells produce at greater than 95% water cut but contribute to about 8% of production. The overall water cut of the Nimr asset is currently 87% and is forecast to increase to 90% over the next ten years causing further deterioration of the reconciliation factor.

As per NFPA standard, every offshore platform is required to test the deluge system 3-yearly. Use of seawater to test the deluge system introduces multiple issues with materials offshore due to direct impingement of seawater coupled with chloride ingestion in instruments and other electrical items. This was experienced[SP(L1] by more senior engineers and operators working on other platforms commissioning and hence KBB was tasked to test the deluge system using freshwater. On the KBB platform, freshwater system was never designed to be used for the deluge, and retrofitting or modifying the platform proved to have major obstacles. KBB investigated use of a barge or standby vessel to conduct this test, but the standby vessel pipeline header did not have sufficient capacity for the required test. KBB then designed an external system using water tanks, rented firewater pump, flexible hoses and pre-fabricated spools for use of fresh water on the deluge system. KBB was not successful on inquiries sent on similar test being conducted on other offshore facilities in the region. The deluge test work pack was developed with due consideration given towards safe execution of work. This paper will present the details of how this was achieved safely offshore, bringing in fundamental innovations to ensure value is safeguarded while ensuring the regulatory requirement is met[SP(L2] which is to test the deluge valve dry yearly or wet test the system 3-yearly. Some of the findings from the deluge test will also be presented.

Salinity variation partly causes the inaccuracy of water cut measurement that leads failure to optimize wells production within the capacity constrains of production facilities. In this paper, salinity compensation method is introduced using Gamma-ray absorption technology, as well as Haimo FM2000SC Water Cut meter, which have the built-in Gamma-Ray salinity compensation capability. Test has been conducted on Haimo FM2000SC to determine salinity contents. The compensation is realized by analysis the received radiation count with the different saline water, and obtaining the coefficient value between these two factors. Testing shows that Haimo water cut meter can achieve accuracy of water cut measurement ± 2.0% absolute with 85% confidence factor. Definitions PDO: Petroleum Development Oman WC: Water Cut. This is defined as ratio of the volume flow rate of water and the total liquid volume flow rate, both volume flow rates should be converted to the same pressure and temperature (generally at the standard conditions). It is generally expressed in a percentage. 1. Introduction During the late 80's the oil and gas industry started to realize that the availability of accurate well testing meters could have a larger economic impact on the infrastructure of oil and gas developments. This has driven the development of high accuracy high water cut in oil industry. Various research projects has been initiated sine the late 80's and the early 90's, both in-house with the oil companies and through Joint Industry Programs (JIP's). Worldwide the application of high accuracy high water cut meters is growing. The water cut meters are being applied in two-phase oil / water flow in combination with flow meter to measure the individual oil and water flow rate. They can be installed either as downstream the two-phase separator in the case of three-phase oil / water / gas flow or in the well head in the case of two-phase oil / water flow. In the last ten years a lot of development has taken place, and at present a degree of maturity is emerging in applied techniques and fabrication of water cut meters by a variety of manufacturers. Still a substantial amount of development and improvement is required, especially in the field of improving accuracy levels over the high water cut range. A study from PDO has showed that the reconciliation factor of some of its fields was deteriorating since 1999 and at the end of year 2000 the asset reconciliation factor had dropped to 0.775. The suggested possible cause of this deterioration was the increase of uncertainty in net oil calculation as a result of inaccuracy in water cut measurement. This has been identified partly due to salinity variation.

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