Pushpa Sharma

Sensitivity study of horizontal length, offset from water oil contact and withdrawal rate of horizontal well in bottom water drive reservoir

Estimation of critical rate is required for maximizing oil production from horizontal well before water breakthrough. Post-breakthrough recovery is dependent on parameters viz: Horizontal length (L), withdrawal rate (Q) and offset from WOC (h). Critical rate has been determined using various analytical methods whereas EUR from horizontal well has been calculated for forty-eight cases (L-4 no’s, Q-3 no’s, h-4 no’s) using commercial black oil simulator. Result of the study shows that maximum impact on cumulative oil production is given by offset from WOC followed by withdrawal rate and lastly on horizontal well length.

Modeling and simulation of gas flow behavior in shale reservoirs

Shale is a growing prospect in this world with decreasing conventional sources of fossil fuel. With the growth in demand for natural gas, there is impending need for the development of the robust model for the flow of shale gas (Behar and Vandenbroucke in Org Geochem, 11:15–24, 1987). So the major driving force behind the working on this major project is the unavailability of desired models that could lead to enhanced production of these wells and that too efficiently. This model mainly includes the movement of shale gas from tight reservoir through the conductive fractures to wellbore and production model of the decline in pressure inside the reservoir with respect to time. This result has been further compared with the help of MATLAB so as to obtain a complete pressure-derived model. The result shows the applicability of this in the real-life projects where it is difficult to model the fractures and obtain the flow rate with them in fractures and how to set the production facilities becomes a question.

Optimization of vertical well completion in a saturated reservoir with bottom water drive for maximizing recovery

ABSTRACT To maximize oil recovery from a bottom water drive reservoir using a vertical well, estimation of transition zone thickness and determination of critical rate are very important. To augment or sustain the oil production and recovery rate, it is necessary to place the well using proper offset from water/oil contact (WOC) and assign a proper liquid rate. The objective of this paper is to establish a development strategy for a bottom water drive reservoir which will maximize the oil production. Analytical methods are first used to find initial approximations of critical production rate, then comprehensive numerical investigation of the relevant parameters affecting water coning behavior is studied using a history matched, corner point gridding three-dimensional reservoir simulation model. Additionally, core and log data were analyzed to determine WOC and transition zone thickness. Establishment of well placement with proper offset from WOC and rate has been carried out in a history matched three-dimensional model. Better understanding of the reservoir in terms of saturation height function (thickness of the transition zone) and performing rate sensitivity at various offsets from WOC has enabled us to place the well at an optimum point and drain the reservoir in an efficient manner.

Application of Inflow Control Devices in Horizontal Well in Bottom Water Drive Reservoir using Reservoir Simulation

Maximizing reserves recovery using horizontal wells requires management of fluid flow through the reservoir. One increasingly popular approach is to use inflow control devices that delay water and gas encroachment and reduce the amount of bypassed reserves. Maximum reservoir contact (MRC) is an important parameter which has several benefits such asEfficient Drainage area, Delayed coning or cusping and Increased Sweep Efficiency. MRC can be achieved using smart wells such as Horizontal wells, Multilateral Wells and Extended Reach Drilling (ERD). With advances in drilling technology over the past 30 years, horizontal and multilateral wells have become a primary design type to develop reservoirs. The need to produce efficiently, economically and environmentally-friendly has promoted the development of extended reach horizontal and multilateral wells which enable greater reservoir contact and lower draw-downs to achieve higher rates than conventional vertical wells. This paper compares the well productivity of Vertical, Horizontal and Horizontal wells with ICD using numerical simulation techniques in three dimensional grid of Upper Assam Arakan Basin. Keywords—Horizontal well, Inflow Control Devices,heel-toe effect, Well Placement, Reservoir simulation, Recovery, Maximum Reservoir Contact, MRC

Modeling of Gas Flow Within the Shale Fracture Network

At present, shale gas has become the greatest source around worldwide in energy supply. For gas production from shale at economic rates, new technologies like horizontal wellbore drilling and incused fracturing are implemented in all shale gas reservoirs. Rate of gas production from shale reservoirs basically depends upon the reservoir properties and the hydraulic fracture properties. This paper concentrates on the modeling and simulation of gas flow within the fracture network. The reservoir model is represented in the form of cube, which contains the pore spaces where the adsorbed gas and free gas are stored. Free gas is present in matrix pore spaces, and in the fractures, adsorbed gas is present on the surface of the kerogen. Once the pressure difference is created, then the gas will flow from the matrix pores to the fractures and to the horizontal wellbore. The horizontal wellbore is connected to a set reservoir cube representation. In this work, an updated dual porosity model has been considered for modeling the gas flow in the reservoir. The basic assumption involved in this model is, one pore space represents the matrix, and the other pore space represents the hydraulic fractures. For describing the gas flow behavior within the matrix, a nonlinear PDE has been developed which is then compiled using JAVA to calculate the pressure variation across the reservoir. In the matrix, the gas flow is considered in all three dimensions, i.e., 3D flow. Accordingly, a three-dimensional reservoir model is developed. Several flow mechanisms like slip flow, non-Darcy flow, and Darcy flow are considered along with the parameters Langmuir pressure and Langmuir volume in this model. The flow of gas in the matrix is considered as single-phase flow. The production data are estimated for a period of three years, and the obtained results are validated using CMG-IMEX reservoir simulator.

Ethanol from maize: an entrepreneurial opportunity in agrobusiness

ABSTRACT India is a developing economy, and an energy-hungry state. With its ever increasing demand for fuel, India is the fourth largest consumer of crude oil in the world and imports 70% of its total demand. Also, to reduce the carbon footprint, the search is on for eco-friendly and renewable sources of energy. In India, one such unconventional fuel is ethanol produced from sugarcane molasses and blended with gasoline for use as biofuel. In this paper, the authors propose an entrepreneurial project to produce ethanol from maize, with an objective to develop a clean & green source of energy and to give a boost to the agricultural economy. Maize is the third most important crop in India, with approximate 85% of areal coverage. It has applications in adhesives, food industry, beverages and breweries for producing ethanol. Ethanol produced from maize has advantages over sugarcane, as the fibrous byproduct makes an excellent animal feedstock and can be further processed for the production of corn starch and syrup, to maximize the profit. The present paper suggests an entrepreneurial opportunity for commercial production of ethanol from maize directly purchased from farmers, creating a win–win scenario for farmers as well as the enterprise.

Integrated approach for maximising recovery from Oligocene reservoir under bottom water drive

The Barail formation of Oligocene age, in the upper Assam basin has major contribution in the oil production from North-Eastern part of India. This is a clastic formation which has been extensively developed initially using vertical wells and in the last decade using horizontal wells. In last 20 years only 13% of OOIP has been recovered due to improper drainage, high water cut and cessation of flow due to low THP. In order to accelerate the production level and recovery factor, a three-dimensional numerical reservoir simulator has been used for evaluating various scenarios (well intervention, vertical and horizontal infill locations, water injection, ICD application) after history matching the model. From the analysis, it is evident that application of ICD along with pressure maintenance is suitable for such reservoir. Depending on the scenario, the recovery factor increased from 13% to 24%. Economic indicators were formulated for all the scenarios at the end. [Received: July 12, 2016; Accepted: December 4, 2016]

Optimization of Ohmic Heating of Fish Using Response Surface Methodology

Abstract Optimization of process variables for ohmic heating (OH) of fish steaks was done by response surface methodology according to Box–Behnken design. The low and high levels of the variables were 3 and 7 min for processing time; 55 and 75 V for applied voltage and 10 and 15 mm for product thickness. Responses studied comprised colour, temperature, hardness, water activity and organoleptic score. It was found that effects of time and applied voltage were significant on all responses. Optimum conditions (desirability = 0.820) obtained by numerical optimization were processing time, 5.75 min; voltage, 75 V and product thickness, 14.4 mm to achieve maximum colour variation, temperature and organoleptic score and lower hardness and water activity. Corresponding to the optimum conditions, the predicted value for temperature was 71.88°C, colour 49.85, hardness 1.125 kg, water activity 0.772 and overall acceptability 7.891.