COMMERCIALIZATION OF N2 RICH NATURAL GAS RESERVOIRS
Albert Curtis III, Sha-Naki Wess, DuyQuang Nguyen and Miguel Bagajewicz

Abstract

With the natural gas supply in the United States not being able to support the nations demand for natural gas, the US will either have to find more sources for natural gas or import more natural gas from foreign countries. One of the potential sources to increase natural gas supply is to use nitrogen rich natural gas. The objective of this study is to identify and analyze potential uses for nitrogen rich natural gas reserves. An economic analysis will be shown on the feasibility of production and commercialization of nitrogen rich natural gas. The separation options include the purification of natural gas by cryogenic distillation, pressure swing adsorption, membranes, and molecular gate technology. The commercialization options include conversion of methane to synthesis gas and its derivates and combustion of natural gas for power generation. A mathematical model was built to determine the best process combination based on maximizing net present worth.

EVALUATION OF PROGRESSIVE DISTILLATION

Daniel Dobesh, Jesse Sandlin and Miguel Bagajewicz


Abstract

Progressive crude distillation (United States Patent number 4,664,785) is being increasingly mentioned as an energy savings alternative to existing crude fractionation columns. One plant using this technology has been built in Europe and different industrial circles are paying increasing attention. This presentation will show under what conditions these claims are warranted. The technology involves successively separating increasingly heavier petroleum cuts in a first series of columns. A second series of columns is being fed by the products of the first one. The first series of columns separate loose cuts of the most volatile components fed to each column. Columns in the second series sharpen the cuts and produce naphtha, kerosene, diesel, and gas oil product streams within specification. An asessment of some of the patent claims will be made for a light and a heavy crude.

Abstract

Natural gas is a valuable fuel with increasing demand is transported from natural reserves to areas of high demand and stored for times when demand exceeds production. In this study, natural gas hydrates were considered as a possibility for the transportation and storage of natural gas. Several designs were considered for the production, shipping, and regasification of natural gas hydrates. Natural gas hydrates were found to be economically less favorable than LNG for the transportation of natural gas primarily due to the lower energy density of natural gas hydrates. However, natural gas hydrates were found to be economically viable for small capacity peak-shaving plants and natural gas storage due to the lower costs associated with natural gas hydrate synthesis.

PRE-FLASH CRUDE FRACTIONATION

Jonathan Peters and Miguel Bagajewicz

Abstract

Heat integration of conventional crude fractionation by use of a single preflash unit has shown to be less energy efficient than conventional units alone when maintaining the same product yield. However, there is a reduction in the heat requirement when the flow rate of gas oil is reduced. Marginal improvements have been shown for heavy crude fractionation while maintaining high gas oil yield. This presentations shows the results of use of multiple preflash units in several configurations. The heat integration of conventional units with multiple pre-flash units is analyzed using both light and heavy crude fractionation and compared to purely conventional units.

TRANSPORTATION OF NATURAL GAS USING LIQUID CARRIERS AT AMBIENT TEMPERATURE
Benedict Thompson and Miguel Bagajewicz

Abstract

Natural gas is currently transported with very established methods like Liquefied Natural Gas (LNG) and Compressed Natural Gas (CNG). A new technology is being researched for transporting natural gas at ambient temperatures and moderate pressures using liquefied hydrocarbons or other solvents. An economic analysis of this technology is essential to implementing it as a viable method for transportation. In this presentation we will cover the results of the economic impact of loading and unloading of the natural gas and the transportation itself. This method will also be compared to the existing methods.

USE OF HEAT INTEGRATED DISTILLATION TECHNOLOGY IN CRUDE FRACTIONATION
Stephanie English, Su Zhu and Miguel Bagajewicz

Abstract

Crude fractionation is a high-energy demand process, requiring approximately 3% of the total energy used in the United States. Currently, there are incentives to reduce energy usage due to rising costs of energy. A recent development in distillation technology that has shown potential savings of up to 60% is the heat-integrated distillation column (HIDC). HIDC columns save energy by recovering excess heat from the rectifying section for usage in the stripping section. However, this technology has only been applied to specific hydrocarbon systems. This study investigates the application of some HIDC concepts in crude fractionation. We will show the new column design and present the results.

USE OF MEMBRANES IN NATURAL GAS SEPARATIONS
Ernest West, Nina Wright, Debora Faria and Miguel Bagajewicz

Abstract

Membranes are increasingly becoming a viable alternative to conventional gas separation technologies such as amine sweetening, pressure swing adsorption and cryogenic distillation. The design of an efficient and economically feasible membrane network is usually performed through step by step comparison of various designs, and flow patterns. We will present an optimization approach that allows the various designs to be compared simultaneously while choosing the optimal separation system. The model is based on mixed-integers nonlinear programming (MINLP) and is based on the concept of superstructures (all possible flowsheets put together from which one is picked).

SWITCHGRASS TO FUELS

Kang-Lih Chey, Amanda Drabek, Lance Lobban and Miguel Bagajewicz

Abstract

Due to government mandate requiring that an increasing percentage of gasoline be derived from renewable fuels, concerns about the environment, and a need to decrease U.S. dependence on foreign oil and fossil fuels, renewable resources have become an important research topic. In particular, there is a desire to develop a liquid fuel suitable for use in automotive engines. One process currently under consideration for this goal is pyrolysis of bio mass. This process uses switchgrass and other cellulosic material to produce a liquid bio-oil. This bio-oil contains too many oxygenates to be used in a car engine. Therefore, research into a catalytic deoxygenation process to upgrade this oil is underway. This presentation will evaluate the design of a pyrolysis and catalytic upgrading system that will produce a liquid fuel. The economic potential for this process will be highlighted and recommendations for future work will be provided.

10:00-10:30

Meet the authors.
Posters & Cookies

SOFTWARE-BASED PIPELINE LEAK DETECTION
Taiwo Akinbola, Elijah Odusina, David Mannel, DuyQuang Nguyen and Miguel Bagajewicz

Abstract

Pipeline leak detection has been a focus of numerous research in industry. There are several methods based on expensive hardware. As an alternative, less costly software based methods have been proposed. These methods make use of the measured flows and pressures to infer through data reconciliation and bias detection methodologies whether a leak or a bias is present. In this presentation, the Generalized Likelihood Ratio (GLR) method proposed by Narasimhan and Mah (1987) is adapted to combined leak detection and instrument bias identification. The methodology is entirely implemented within a simulator.

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GROUNDWATER REMEDIATION
Taren Blue , Laura Place and Miguel Bagajewicz



Abstract

This presentation discusses the use of computational fluid dynamics and mathematical modeling to optimize groundwater remediation. We use simplified two dimensional models first and Fluent (a well-know fluid flow simulator) to later obtain three-dimensional flow through an aquifer with varying contamination profiles. We consider different well configuration arrangements, pumping rates, contamination shapes and concentrations to predict the cleaning of a contamination plume with varying shape and concentration profiles, using varying pumping rates, number of wells and configurations. In addition, to optimize the process we consider changing well configurations with time to optimize the process. Examples of successful implementation of our technique will be shown.

Abstract

In this presentation we outline a new methodology to design natural gas pipelines over a long time horizon considering and determining timely expansions by the addition of compressors. The problem is framed in the context of a capacity expansion problem and is solved using both a mixed integer linear programming model and a non-linear model. We compare our methodology to the current state-of-the-art methodologies, highlighting the limitations of the latter and showing the advantages of the former, especially in the case of branched networks.

Abstract

Water management in process plants have been the object of several studies in which the option of reusing water in effective ways has been explored. In addition, the possibility of regenerating freshwater out of polluted water to further reuse it has been mentioned. The extreme case of this is the so-called zero-liquid discharge cycles, which has been found possible and even economically beneficial in certain cases. One of the shortcomings of all these methods is that they do not incorporate good information about water treatment costs, both operating and investment. After explaining the overall problem and showing some of the exiting results, this presentation will focus on showing how one can generate generalized correlations of these costs so that they can be incorporated in the mathematical optimization models used to design water reuse/regeneration systems.

Abstract

Optimization of maintenance scheduling can save a processing plant substantial operating expenses. This work expands upon a previously developed methodology for assessing the effectiveness of preventative and corrective maintenance-scheduling guidelines on a chemical processing plant. Here, the model is applied to a larger plant than it was previously tested on and is expanded to include a risk analysis. In addition, a genetic algorithm is used to optimize all variables simultaneously. Optimal parameters such as labor force size and preventative maintenance intervals are presented for the larger plant.

GENERATION OF THERMOCHEMICAL CYCLES FOR H2 PRODUCTION THROUGH WATER SPLITTING
Jeffrey Jenneman , James Phan, DuyQuang Nguyen and Miguel Bagajewicz

Abstract

The diminishing supply of hydrocarbons and their negative environmental impact has resulted in a great need to find alternative energy sources. Hydrogen production from the chemical decomposition of water using multiple reactions resulting in the net production of hydrogen and oxygen are termed water splitting cycles. Previous work at OU focused on developing good efficiency evaluation procedures. In this presentation we describe a computer algorithm that was implemented to find new potential water splitting cycles and evaluate their thermodynamic feasibility. The goal is to find cycles that are viable at low reaction temperatures.

ECONOMIC POTENTIAL OF STRANDED NATURAL GAS HYDRATES
John Hudson, Elizabeth Wyant and Miguel Bagajewicz

Abstract

With the supply of conventional energy sources on a decline and the demand for them increasing, the need for a large and stable supply of unconventional resources is growing fast. Natural gas hydrates are a potential source of large amounts of natural gas that can be found on the ocean floor and in permafrost regions, such as Alaska, Siberia and eastern Russia. This presentation shows the results of studies about the commercial feasibility of producing natural gas hydrates from the peninsula region of Kamchatka, Russia and selling it to markets in either China or Japan. A production model was constructed to determine the logistics of surface equipment placement. In addition, the difference in prices between transporting the produced natural gas via pipeline and tanker ship were compared. Preliminary calculations compare the commercial viability of constructing an LNG plant on the western coast of Kamchatka to selling gas to China via pipeline.

UTILITY-INTEGRATED BIOREFINERIES
James Berry , Jenny Cochran , Mary page, DuyQuang Nguyen and Miguel Bagajewicz

Abstract

In this presentation we will show how capacity planning models can be used to plan investments in biorefineries. For this, we have considered several processes belonging to a chemical supply chain that can be fed by a raw material, such as switchgrass, and used to produce valuable commodities. To build our model we have considered 58 possible processes to choose from, part of which are 12 chemicals chosen by the U.S. Department of Energy for production of value-added chemicals from biomass. The model maximizes net present value, considers budgeting conditions to self finance expansions and determines what process ought to be in the biorefinery, its initial capacity, as well as construction time and the timing and size of future expansions. Projected raw material availability, market projected demand and prices, as well as transportation costs are included. Among other results, the model is also able to provide the location of the refinery. All these features notwithstanding we also added the integration of centralized utilities to determine the optimal value added chain of processes, a feature that has not been considered in any previous models.

12:30-1:30

Meet the authors.
Posters & Light Lunch

Meet the authors.
Posters & Light Lunch

ACCURATE SCIENCE-BASED PHYSICAL AND ECONOMIC MODELS IN SUPPORT OF INTELLIGENT NATURAL GAS FACILITY REGULATIONS
Binil Starly and Hank Grant (Industrial Engineering)

Abstract

There exists a gap between the understanding of the EPA and the current state-of-the-art in the natural gas industry with respect to the management of emissions from natural gas facilities. This gap arises from the expense and time-frame necessary to develop and understand the effects of regulations on emissions from natural gas facilities based on scientific principles and mathematical/economic models. Thus there is a need for a comprehensive decision support tool which can enable the evaluation of the effects of various emission regulation norms through the development of a facility classification scheme, using a database of current natural gas facilities, production costing simulation and optimization algorithms. With the use of this tool, plant system operators and engineers can make an informed decision regarding the choice and implementation of suggested emission regulation techniques while assessing environmental and economic impact.

NOVEL METHODS FOR INSTRUMENTATION NETWORK DESIGN IN PROCESS PLANTS


DuyQuang Nguyen, Sugumar Sanjay and Miguel Bagajewicz

Abstract

Process plats make use of instrumentation for a variety of purposes: control, fault detection and identification and monitoring in general (production accounting and quality assurance). The instrumentation that makes this possible is sometimes about 10% or even more of the fixed capital investment. Thus, methods to determine the appropriate instrumentation at the lowest cost have been proposed. In this presentation, we will show how highlights of a methodology that allows the determination of minimum cost networks featuring a certain degree of accuracy ( a term that involves precision and control of bias).

NONISOTHERMAL MULTIPHASE FLOW IN PIPELINES UNDER NONEQUILIBRIUM CONDITIONS
Guillermo Michel and Faruk Civan (Petroleum Engineering)

Abstract

The flow of reservoir fluids in oil pipelines and wells is accurately modeled and simulated using a rigorous theoretical approach by considering the slippage occurring and the relaxation in time during multi-phase flow under nonequilibrium conditions. An accurate liquid holdup prediction method related to the velocities of the various phases is applied. The relaxation time of the gas phase separation from the liquid phases as pressure declines is facilitated for accurate modeling. The validity of the improved modeling approach is demonstrated using the field data obtained under steady-state conditions. The variation of the pressure, temperature, quality, and relaxation time are simulated along the pipelines and wells for typical cases of practical importance.

Abstract

Removal of Nitrogen, CO2 and H2S from gas is an important step in gas conditioning for further separations or direct use. Once these impurities are removed from the gas, the next step is the removal of ethane and heavier components. The removal of CO2 and H2S is traditionally done through a process called amine sweetening. Nitrogen, in turn is removed using membranes or PSA. Finally ethane and heavier components are separated using cryogenics methods. Because these methods are not simple, nor inexpensive, finding alternatives would be beneficial. In this presentation, we will overview the aforementioned methods and we will present the economics of a new technology for separating impurities out from natural gas that has been developed at OU.

VALUATION OF GAS STORED IN SALT CAVERN
STORAGE FACILITIES
Michael Bond and Hank Grant (Industrial Engineering)

Abstract

Since natural gas production is relatively inelastic towards demand in the short term, underground storage is used as a buffer against periods of high demand. Of the three most common storage facility types, depleted reservoirs, aquifers and manmade salt caverns, the latter is the most costly to develop. The challenge then is to take advantage of the unique features of salt cavern facilities and maximize profits through efficient operation; well-timed injection and withdrawal of gas. The valuation of a commodity in storage is a challenging problem and has been the subject of study for decades. We investigate selected existing valuation approaches, looking for ways to leverage salt-cavern-specific physical characteristics for financial advantage. The basis for our valuation is the Black-Scholes model for pricing options. Then, applying Monte-Carlo methods and simulation, we model combinations of characteristics in multi-cavern facilities and their impact on profitability. We describe the theory behind our work, our analytical framework and provide numerical results of our analysis. Our approach offers increased efficiency in salt-cavern gas storage facilities.

EVALUATION OF LNG PRODUCTION
TECHNOLOGIES
Ayema Aduku, Oluwaseun Harris, Valerie Rivera, Debora Faria and Miguel Bagajewicz

Abstract

There are numerous documented methods for the liquefaction of natural gas but only a handful are actually implemented commercially. The liquefaction process requires the natural gas to be cooled using various methods of cryogenic processes and also be depressurized to atmospheric conditions for easier and safer storage. This presentation shows the result of an analysis of twelve total processes based on their capacity, fixed costs and their operating efficiency. Eight of the eleven processes are currently established in various parts of the world. The four remaining processes are in developmental stages and each patent description is used to simulate each process and determine its feasibility in industry. The equipment and utility costs are determined for different capacities. The most economical processes as a function of capacity will be identified.