Modeling Productivity Index for Long Horizontal Well

The rising energy demand is causing the petroleum industry to develop unconventional oil resen'oirs; however, the primary recovery factor is low in these types of reservoirs. Alternative methods to increase recovery need to be studied. This paper analyzes the impact of CO2 flooding a sector of the Elm Coulee field using reservoir modeling. The sector is two miles by two miles and consists of six original single-lateral horizontal wells. Two different reservoir models are built for the sector: a primary recovery black oii model and a CO2 flood solvent model. They are used to determine the additional recovery due to a CO2 flood. Furthermore, the CO2 flood model is executed with different scenarios to determine the best well locations and injection schemes. The models demonstrate that CO2 flooding horizontal wells in the Elm Coulee field increases production. Comparison of vertical and horizontal injection techniques indicates continuous horizontal CO2 injection is more efficient; it yields higher injection rates, and it is also beneficial for long-term recovery. Focusing on horizontal injection, the best scenario involves the practice of drilling new injectors and producers aiong with converting existing producers to injection wells. In order to satisfy production requirements, production wells can be drilled such that there is an injector between two producers. This type of arrangement on horizontal injection increases the field recoveiy factor over 15% after eighteen years of injection.

“…Source and sink terms, q^., are used for both the injection and production wells in the model [11]. By definition, production is positive and injection has negative terms, -<?".…”

Section: Reservoir Modelingmentioning

confidence: 99%

CO2 Flooding to Increase Recovery for Unconventional Liquids-Rich Reservoirs

Hoffman

Shoaib

2013

“…Horizontal wells have become quite an established and attrac tive technology in today's reservoir development and the pressure losses estimation along the completion have been recognized as a complicated and significant topic with considerable theoretical and practical values [1][2][3][4][5][6]. Flow characteristics in horizontal wells are different from that in regular pipes due to the wall perforations and continuous fluid influx.…”

Section: Introductionmentioning

confidence: 98%

A New Comprehensive Model for Predicting the Pressure Drop of Flow in the Horizontal Wellbore

Zhang

Wang

et al. 2014

Over the past two decades, the modeling of flow in a perforated pipe with influx through wall openings has been recognized as a key topic especially in the field of horizontal wells. In this paper, based on the theoretical analysis and previous research achieve ments, combining with the new measured data sets stemming from the large-scale experi mental apparatus designed and constructed recently at China University of Petroleum (CUP), a new comprehensive model has been developed for the prediction of pressure drop regarding single-phase flow in horizontal perforated pipes with wall influx, in which new correlations for calculating the hydraulic friction factor and momentum correction factor of variable mass flow are given. The presented model is then implemented using the visual basic.net package and validated against two data sets obtained on single-phase water flow and single-phase oil flow. Predictions of the new model and frequently used Ouyang model are also compared based on the new experimental data. Results show that the model given in this article can not only properly represent the complex mechanisms o f flow in the horizontal wellbore, such as the resistance caused by wall perforations and the drag reduction or so-called lubrication effect caused by wall injection, but also has a preferable prediction accuracy. Compared with the water flow data and the oil flow data, the absolute average percentage errors of the proposed model are, respectively, 4.5% and 5.0%, which demonstrates better performance and wider application range than Ouyang model.

“…The first analytical wellbore pressure drop model only addressed the friction pressure drop [23]. Recently, a new mechanistic annulus model is presented for calculating the frictional pressure losses of drilling fluids [24] and a new horizontal productivity model considering pressure loss is proposed [25]. Then a general guideline whether the pressure drops can be ignored was proposed [26].…”

Section: Introductionmentioning

confidence: 99%

Performance Prediction of Gel Water Shutoff in Horizontal Wells Using a Newly Coupled Reservoir–Wellbore Model

Chen

Feng

Wang

2014

Water shutojf is a commonly used method to mitigate the early breakthrough in horizontal wells. Gel is frequently used as an effective water shutoff agent in mature fields, especially for horizontal wells in recent years. However, the relevant water shutoff prediction model lacks the accurate physical description of the gelation phenomenon. Using the conventional model, which simply accounts for the gelation mechanisms, does not allow us to predict the horizontal wells performance correctly. In this paper, a newly coupled reservoir-wellbore model for horizontal wells gel water shutoff prediction is presented. A conventional gel simulator is used to simulate the gel injection process in the reservoir and then modified to predict the horizontal well performance after the treatment. The time-varying residual resistance factor model and viscosity model is developed to simulate the gel degradation process. Especially, the wellbore pressure drop calculation takes account for the non-Newtonian behavior during and after the get injection. An explicit modular coupled scheme, which consists of reservoir modular and wellbore modular, is adopted to numerically predict the horizontal wells performance. The newly presented method not only simulates the gel injection process but also predict the water shut off performance in horizontal wells. A field horizontal water shutoff case prediction shows that the coupled modeling method can give satisfactory results to guide the water shutoff treatment.