Mitigation of Methane Emissions from Coal Mine Ventilation Air

U.S. EPA\u27s coalbed methane outreach program, (CMOP) has prepared a technical assessment of techniques that combust trace amounts of coal mine methane contained in ventilation air. Control of methane emissions from mine ventilation systems has been an elusive goal because of the magnitude of a typical airflow and the very low methane concentrations. One established and cost-effective use feeds the air into a prime mover in lieu of ambient combustion air. This method usually consumes just a fraction of the flow available from each ventilation shaft. The authors evaluated the technical and economic feasibility of two emerging systems that may accept up to 100% of the flow from a nearby shaft, oxidize the contained methane, and produce marketable energy. Both systems use regenerative, flow-reversal reactors. One system operates at 1000°C, and the other uses a catalyst to reduce the combustion temperature by several hundred degrees. Above certain minimum methane concentrations the reactors can exchange high quality heat with a working fluid such as compressed air or pressurized water. This paper discusses two illustrative energy projects where the reactors produce energy revenue and greenhouse gas credits and yield an attractive return on invested capital

On-line Optimization-Based Simulators for Fractured and Non-fractured Reservoirs

Oil field development is a multi-million dollar business. Reservoir simulation is often used to guide the field management and development process. Reservoir characterization and geologic modeling tools have become increasingly sophisticated. As a result the geologic models produced are complex. Most reservoirs are fractured to a certain extent. The new geologic characterization methods are making it possible to map features such as faults and fractures, field-wide. Significant progress has been made in being able to predict properties of the faults and of the fractured zones. Traditionally, finite difference methods have been employed in discretizing the domains created by geologic means. For complex geometries, finite-element methods of discretization may be more suitable. Since reservoir simulation is a mature science, some of the advances in numerical methods (linear, nonlinear solvers and parallel computing) have not been fully realized in the implementation of most of the simulators. The purpose of this project was to address some of these issues. {sm_bullet} One of the goals of this project was to develop a series of finite-element simulators to handle problems of complex geometry, including systems containing faults and fractures. {sm_bullet} The idea was to incorporate the most modern computing tools; use of modular object-oriented computer languages, the most sophisticated linear and nonlinear solvers, parallel computing methods and good visualization tools. {sm_bullet} One of the tasks of the project was also to demonstrate the construction of fractures and faults in a reservoir using the available data and to assign properties to these features. {sm_bullet} Once the reservoir model is in place, it is desirable to find the operating conditions, which would provide the best reservoir performance. This can be accomplished by utilization optimization tools and coupling them with reservoir simulation. Optimization-based reservoir simulation was one of the project goals. {sm_bullet} Providing remote access to the simulators developed was also one of the project objectives. The basic methods development is presented in Chapters 1-3. Development of a flux continuous finite element algorithm is presented with example calculations in Chapter 1. This is followed by discussion of three-dimensional, three-phase development in Chapter 2. A different numerical method, the mixed finite element method is presented in Chapter 3. Verification of the methods developed is described in Chapter 4. Introduction to fractured reservoir simulation is provided in Chapter 5 with an example of a fractured reservoir simulation study of a faulted reservoir in North Sea. Chapter six contains several examples of two dimensional simulations, while chapter 7 contains examples of three-dimensional simulation. In Chapter 8 optimization techniques are discussed. Chapter 9 contains a roadmap to use the remote programming interface for the fractured reservoir simulator

Enhancing the Effectiveness of Carbon Dioxide Flooding by Managing Asphaltene Precipitation

Objectives of this project was to understand asphaltene precipitation in General and carbon dioxide induced precipitation in particular. To this effect, thermodynamic and kinetic experiments with the Rangely crude oil were conducted and thermodynamic and reservoir models were developed

Technical aspects of oil shale production and processing

presentatio

RESERVOIR CHARACTERIZATION OF THE LOWER GREEN RIVER FORMATION, SOUTHWEST UINTA BASIN, UTAH

Reservoir simulations of different fields in the Green River Formation are reported. Most extensive simulations were performed on the Monument Butte Northeast unit. Log data were used to construct detailed geostatistical models, which were upscaled to obtain reasonable number of grid blocks for reservoir simulation. Porosities, permeabilities, and water saturations required for reservoir simulation were thus generated. Comparison of the production results with the field data revealed that there was a phenomenological deficiency in the model. This was addressed by incorporating hydraulic fractures into the models. With this change, much better agreement between simulation results and field data was obtained. Two other fields, Brundage Canyon and Uteland Butte, were simulated in primary production. Only preliminary simulations were undertaken since a number of critical data elements were missing and could not be obtained from the operators. These studies revealed that the production performance of the Brundage Canyon field is much better than what can be predicted from simulations of a typical non-fractured, undersaturated reservoir. Uteland Butte field performance was that of a typical undersaturated reservoir

In situ production of Utah oil sands

presentationAnalysis of issues relevant to in situ production of Utah oil sands, presented at the 2009 Western U.S. Oil Sands Conference by Milind Deo, Professor, Department of Chemical Engineering, University of Utah

Western U.S. oil sands and in-situ processes

presentatio

RESERVOIR CHARACTERIZATION OF THE LOWER GREEN RIVER FORMATION, SOUTHWEST UINTA BASIN, UTAH

Log data (porosity and water saturation) for D and the C sands was available at 0.5 foot intervals. The data was imported into HERESIM, a geostatistical tool. This permitted assigning constraining surfaces

Deliverable 3.1.4 -- Final reservoir report and field-scale models Bluebell Field, Utah, Class 1

The objective of this project were to: (1) Simulate parts of the reservoir using the conventional dual-porosity, dual-permeability approach, generate progressively complex reservoir models and use the production history match results to quantify formation damage; (2) Examine the effect of the numerical aspects such as grid sizes and fracture properties on the simulations results; (3) Evaluate the effect of fluid thermodynamic properties on production; and (4) Study effect of inclusion of fractures on variability in production from stochastically generated reservoir models

Oil sands production technologies

presentationAn overview of oil sands production technologies for Utah reserves