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This paper describes a systematic assessment artificial lift methods for a heavy oil development in Kuwait. The main recovery strategies that were being considered for the development consisted of different sequencing of primary production, cyclic steam stimulation and steam flooding, with both vertical and horizontal wells.In 2007, Kuwait Oil Company drilled five vertical wells in their heavy oil fields, as a precursor to the full field development planned in the coming years. These five wells represented the first major activity in the formation since the 1980s when two cyclic steam stimulation pilot tests were conducted. The characteristics of the development and of the associated planned recovery strategies presented several AL challenges that needed to be assessed.This work consisted of an assessment of the strengths and weaknesses of various AL systems and a ranking of these systems according to well geometry, oil viscosity, targeted flow rate and the recovery method. The assessment and ranking were mainly based on vendor quoted capabilities, focused wellbore modelling and lessons learned from other heavy oil field cases around the world. While significant experience with rod pumps in cyclic steam stimulation exists in Canada, the lessons learned from that experience needed to be evaluated due to the differences with the Kuwait heavy oil development, such as the requirement to "easily" transition from primary to thermal production and the possible use of metallic stator progressing cavity pumps.This paper provides guidance to other developments around the world in regards to heavy oil AL selection and to how best to apply lessons learned from existing heavy oil developments.

A comparative risk assessment was conducted to evaluate the risk associated with a Steam Assisted Gravity Drainage (SAGD) well blowout. The main comparison was between an isolated (double barrier) completion and an open (single barrier) completion used in conjunction with an effective blowout response plan. The target application was a SAGD pilot project in the Orinoco Belt in Venezuela. The overall approach for the risk assessment included the investigation of the blowout flowing potential of the SAGD wells pair through reservoir modelling, the estimation of the probability of a blowout using fault-tree analysis, and the evaluation of the possible consequences (life safety, environmental and economic) of such blowout using various quantitative consequence models. Details of this approach are discussed in this paper, along with the results specific to the target application. Results of this work can provide guidance for similar operations where decisions regarding completion options and blowout response plans are required. One key result was that, for this specific SAGD pilot project, a blowout response plan must be able to reduce the blowout duration substantially (from 3 days to 1 day for environmental risk, and from 3 days to 2 hours for economic risk) for the environmental and economical risks associated with a open completion to be comparable to those of an isolated completion. Introduction A Steam Assisted Gravity Drainage (SAGD) pilot project is currently being considered for a heavy oil development in the Orinoco Belt in Venezuela. Under the expected operating conditions of the pilot, it is anticipated that both the injection and the production wells will be able to flow unassisted to surface should a loss of well control incident occur. Industry practice regarding the design of such flowing wells dictates that the well completion include double barriers in the production tubing string, e.g. the flow tee plus a downhole safety valve (DHSV), and in the production casing annulus, e.g. the tubing head plus a downhole packer. Unfortunately, downhole equipment suitable for such a high temperature application does not currently exist. A possible alternative to the double barrier completion is to use a single barrier completion in conjunction with an effective blowout response plan. To evaluate the risks associated with this alternative, a comparative risk assessment was conducted. The main purpose of this paper is to present the overall approach used in the risk assessment, which includes the investigation of the blowout flowing potential of the SAGD well pair through reservoir modelling, the estimation of the probability of a blowout using fault-tree analysis, and the evaluation of the consequences of such blowout using various quantitative consequence models. Results from each of these segments for the specific pilot project are presented as an example of applying the approach. As the pilot project is set in Venezeula, it is important to note that some characteristics of the application are different from the common SAGD projects in Canada, such as a higher permeability (~ 30 D) and a higher initial reservoir temperature (~ 48°C).

Under the expected operating conditions of a Steam Assisted Gravity Drainage (SAGD) pilot project, it is anticipated that both the injection and the production wells will be able to flow unassisted to surface should a loss of well control incident occur. Industry practice regarding the design of such flowing wells dictates that the well completion include double barriers in the production tubing string and the production casing annulus. Unfortunately, downhole equipment suitable for such a high temperature application does not currently exist. To help evaluate the comparative risk between a double and single barrier completion, a reservoir modeling study was conducted to investigate the flowing potential (flow rates, durations and composition of the fluids) of the SAGD pilot wells under various blowout scenarios. This paper presents the results of this reservoir modeling study in terms of the coupled wellbore/reservoir behavior during the blowout condition. A commercial coupled wellbore/reservoir simulator was used along with a "custom" code developed to include a critical choke velocity constraint into the reservoir simulation considerations. The various blowout scenarios investigated include flow through both the injection and the production wells, at three different points during the production life of the well pair (beginning of the steam injection phase, middle of the steam chamber development and end of the steam injection phase) and through three possible flow paths (through the tubing, through the tubing-casing annulus and through both the tubing and the annulus). The reservoir modeling confirmed that both the injection and the production wells in this SAGD application have the potential for a blowout lasting for significant periods of times should a loss of well control occur, and with liquid rates that can be over 50 times the normal production liquid rates. Introduction The availability of successfully tested technology to exploit the huge bitumen and heavy oil reserves worldwide, along with the high oil price scenario are boosting the feasibility of bitumen and heavy oil production projects. In this context, Steam Assisted Gravity Drainage (SAGD) has emerged as one of the most efficient thermal recovery technologies to produce those resources. The usual way to predict the production performance of SAGD processes is by using reservoir thermal simulation. When long term production predictions are made, a classical sink/source formulation to describe the wellbore in the reservoir model is commonly used, under the assumption that localized transient phenomena within the wellbore doesn't affect the final SAGD oil recovery. That formulation assumes that the production/injection constraints, which normally include constant pressure or constant flow rate, will be independently applied at each point within the gridblocks where the wellbore is placed, in the reservoir simulation model, without any consideration of the fluids flow through the wellbore.