Extending the Life of Mature Assets: How Integrating Subsurface & Surface Knowledge and Best Practices Can Increase Production and Maintain Integrity

Abstract

Many producing assets in the world have reached the so-called mature phase of development. Some of these assets have been producing for 30 to 40 years or more, which is typically beyond the design life, and have reached a water to oil ratio of 3 to 9 or more. There are many issues that affect the productivity and economic viability of these fields. Some of the challenges include integrity uncertainty in the wells, flow lines, and facilities; production bottlenecks due to the shift in gas, oil and water ratios; erosion/ corrosion; increased sand production and handling costs; high chemical consumption and treatment costs; and obsolete monitoring and control systems that are incompatible with new technologies and which contribute to the need for a large number of operations staff. Generally operators are faced with the commercial decision whether to sell the asset to a low cost operator, reinvest in the asset, or incur the cost of decommissioning.While the number and complexity of these challenges are significant, there are nevertheless a number of viable options for extending the economic life of such assets. Hydrocarbon recovery and production from these fields can be enhanced by infill drilling; acid and fracture stimulation; by implementing a range of remediation techniques such as recompletion with smart systems to reduce water and solids influx to surface facilities; and by the implementation of improved and enhanced recovery methods. Selecting the optimal strategy requires a holistic perspective on subsurface issues, wells, and surface facilities, and an ability to make projections of integrated performance. This is greatly facilitated by first developing a root cause understanding of the reservoir and production fluid characteristics, and second, the use of analysis tools that allow quick and reasonably accurate assessment of options.In order to increase value from matured fields, the goal is to increase oil recovery from the historical average of 35% and to optimize production by improving the operational efficiency. To achieve this goal, in this paper we will put forward two key imperatives that extend the life of a mature field: (1) Finding and accessing the by-passed oil and (2) Maintaining High uptime during Asset production and operation.In this paper, several mature fields in Europe, Far East and Middle East are analyzed and presented in order to: -highlight the root causes for either low production and or higher operating costs; -assess the impact of both surface and subsurface uncertainties in multiple development planning scenarios; -develop the best strategies and options for improved reservoir, well and facilities management; -demonstrate the contributions of implemented new technologies that optimized performance of artificial lift, minimized downtime by well intervention and reduced operational costs by fluids flow assurance in well and surface facilities; and -list the technical and economical challenges that still face the industry.

Comparative Analysis of Produced Water Collected from Different Oil Gathering Centers in Kuwait

“…The authors found that the TDS concentration of produced water in the western United States is between 1000 mg/L and 400,000 mg/L, but the average TDS concentration of produced water from most formations was less than 100,000 mg/L. Additionally, in the same study [10] covering produced water in the western United States, the produced water, oil and grease content was found to be in the range of 40 mg/L to 2,000 mg/L. The properties and composition of contaminants in produced water vary considerably in different geological formations; therefore, in this study, produced water samples from various oilfields in Kuwait were analyzed to determine their physical properties and dissolved substances, which are useful in determining the environmental and economic risks from discharging such water.…”

“…The salt content in produced water is an important matter of concern in the oil production sector because the salinity and Total Dissolved Solids (TDS) of the produced water can be higher than the salinity and TDS of seawater, as shown in a previous study [10]. The authors found that the TDS concentration of produced water in the western United States is between 1000 mg/L and 400,000 mg/L, but the average TDS concentration of produced water from most formations was less than 100,000 mg/L.…”

Flow assurance analysis in Front End Engineering Design (FEED) of Subsea Flowline and Riser

“…Flow assurance encompasses a broad spectrum of disciplines within subsea production engineering [13]. It is primarily concerned with guaranteeing uninterrupted and efficient flow of hydrocarbons from the reservoir to the processing facility [2]. Several key aspects contribute to this overarching objective, including: hydrate management, wax management, scale management, slugging & flow regimes and erosion & corrosion.…”

Analytical Methods for the Determination of Mercury Species Using Cold Vapour Based Spectrometry: Application in Challenging Samples and Use of Nanoparticles as Photocatalytic Agents

“…Therefore, mercury speciation analysis in PW samples requires efficient separation of the analytes before derivatization [48]. as the samples present very high chloride content (salt supersaturation is common).…”

“…Since the method aimed at the determination of Hg 2+ and CH3Hg in PW, the effects of oil and salt content on the generation of Hg vapor was studied. Sodium chloride is the main inorganic component in PW, being present at higher concentrations than in seawater (typically from 30 to 400 g L -1 ) [48,142]. Because of the high formation constants, at high concentrations of chloride, it is possible that Hg 2+ tend to form stable HgCln (2-n) complex ions that may hinder the reduction of Hg 2+ to Hg 0 [143][144][145].…”