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Introduction and Overview

Over the last decade, the United States has experienced a growing demand for energy, a demand that is expected to increase at a remarkable rate. During this same time, environmental concerns have continued to drive exploration into a variety of options to minimize adverse environmental impacts associated with extraction, transportation, and consumption of fossil fuels. Although electric power can be generated using hydropower, nuclear energy and the burning of fossil fuels (including coal, natural gas, and liquid petroleum), there has been limited historical use of oil to produce electricity (National Energy Policy Development Group, 2001). Recent work completed by the Energy Information Administration (2001) of the Department of Energy indicates that electricity generation fueled by natural gas and coal will increase through 2020 to meet growing demand for electricity, and offset the projected retirement of existing nuclear units (Figure 1.1). Projections for power generation from natural gas, coal, and nuclear power are expected to increase as a result of higher projected electricity demand and the improved operating costs and performance of nuclear plants. The use of renewable energy technologies for electricity generation is projected to grow slowly because of the relatively low costs of fossil-fired generation and because electricity restructuring favors less capital-intensive natural gas technologies over coal and baseload renewables. As also shown in Figure 1.1, the firing of liquid petroleum products, such as No. 6 fuel oil, accounts for a relatively small and declining fraction of electricity generation (Energy Information Administration, 2000). Despite this overall trend, electric generators have been increasing their use of Group V fuels (often referred to as low API [American Petroleum Institute] gravity oil, or LAPIO [Low API oil]) because of the rela-



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Spills of Emulsified Fuels: Risks and Response 1 Introduction and Overview Over the last decade, the United States has experienced a growing demand for energy, a demand that is expected to increase at a remarkable rate. During this same time, environmental concerns have continued to drive exploration into a variety of options to minimize adverse environmental impacts associated with extraction, transportation, and consumption of fossil fuels. Although electric power can be generated using hydropower, nuclear energy and the burning of fossil fuels (including coal, natural gas, and liquid petroleum), there has been limited historical use of oil to produce electricity (National Energy Policy Development Group, 2001). Recent work completed by the Energy Information Administration (2001) of the Department of Energy indicates that electricity generation fueled by natural gas and coal will increase through 2020 to meet growing demand for electricity, and offset the projected retirement of existing nuclear units (Figure 1.1). Projections for power generation from natural gas, coal, and nuclear power are expected to increase as a result of higher projected electricity demand and the improved operating costs and performance of nuclear plants. The use of renewable energy technologies for electricity generation is projected to grow slowly because of the relatively low costs of fossil-fired generation and because electricity restructuring favors less capital-intensive natural gas technologies over coal and baseload renewables. As also shown in Figure 1.1, the firing of liquid petroleum products, such as No. 6 fuel oil, accounts for a relatively small and declining fraction of electricity generation (Energy Information Administration, 2000). Despite this overall trend, electric generators have been increasing their use of Group V fuels (often referred to as low API [American Petroleum Institute] gravity oil, or LAPIO [Low API oil]) because of the rela-

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Spills of Emulsified Fuels: Risks and Response FIGURE 1.1 Electricity generation by fuel, 1970-2020 (billion-kilowatt hours) (Energy Information Administration, 2000). tively low cost and high Btu (British thermal unit) values (Michel et al., 1995; National Research Council, 1999). Included in this group is a special class of fuels termed emulsified fuels. UNDERSTANDING EMULSIFIED FUELS Emulsified fuels are multicomponent fuels analogous to water-in-oil emulsions. These fuels may possess combustion properties considerably different (and in some instances more favorable) than those of the base fuels from which they are formed due to the presence of different compounds in the reaction environment and the physical changes in atomization behavior (Miller and Srivastava, 2000). Emulsified fuels include three major variants, coal-water slurries, water-in-oil emulsions, and bitumen-water emulsions. Coal-based multicomponent fuels were developed primarily in the 1970s and 1980s as an alternative to fuel oils. However, when the price differential between crude oil and coal decreases, interest in coal-based multicomponent fuels also decreases (Miller and Srivastava, 2000). Conversely, the volatility of crude oil prices (especially when compared to the price of coal, which has historically been stable) makes conversion to liquid petroleum-based fuels less appealing in the long run. Similarly, water-in-oil emulsions tend to vary in price more radically than coal (though less so than crude oil1). These emulsified fuels are designed to 1   In general, there is very little production of emulsified fuels for use in the United States. Annual production and sales of emulsified fuels seem to be in the range of about 190,000 to 240,000 barrels

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Spills of Emulsified Fuels: Risks and Response improve the combustion properties of the petroleum component (usually a distillate; Miller and Srivastava, 2000). By far the best known and studied emulsified fuel2 is a bitumen-water emulsion named Orimulsion produced by Bitúmenes Orinoco, S.A. (BITOR), a subsidiary of the Venezuelan national oil company Petroleos de Venezuela, S.A. (PDVSA). Unlike oil, the price of bitumen is extremely stable and predictable. The large reserves and limited market for bitumen have allowed BITOR to offer long-term contracts at attractive rates. Thus, Orimulsion is seen as being cost-competitive with other power generation fuels leading to greater interest in its use worldwide. The use of Orimulsion requires similar infrastructure to that used to burn liquid petroleum for power generation. Power generation plants that currently use No. 6 fuel oil are the most easily converted to the use of Orimulsion. Therefore the most common comparison for risk assessment of spills of Orimulsion in the literature is with No. 6 fuel oil. The comparison in this report therefore reflects the most common potential uses of Orimulsion. Orimulsion is composed of bitumen (~70 percent), fresh water (~30 percent), and surfactant and stabilizer (<0.2 percent). As its name implies, the bitumen is produced from the Orinoco belt in Venezuela, one of the largest reserves of petroleum in the world (estimated to be 300 billion barrels). Orinoco bitumen is highly weathered and extremely viscous (viscosity > 10,000 cP at 30°C; for comparison the viscosity of water is 1 cP; honey, 10,000 cP; and molasses,     per year. There has been more production and use in the past, but many customers seem to have switched to natural gas. There is hope on the part of fuel and surfactant suppliers that increased natural gas prices will help to shift interest back to emulsified fuels. At this time that does not seem to be happening to a major degree, but one supplier did note that its sales increased by about 40 percent from 1999 to 2000 due to gas price increases. All current sales discussed by the companies contacted were to industrial customers as opposed to utilities. All fuel sales were on the East Coast, either in the Northeast or in North Carolina. Contacts at these companies were not aware of any emulsified fuel suppliers other than those discussed here. 2   There is no category for emulsified fuels in the Thomas Register, and a search of various combinations of “emulsion, oil, fuel, petroleum” does not identify any company that produces emulsified fuel oils. However, the Environmental Protection Agency has conducted tests of fuels from two companies that market emulsified fuel oils, Industrial Fuel Company of Hickory, N.C., and Clean Fuels Technology (CFT) of Reno, Nev. (formerly A-55 Clean Fuels, Ltd.). CFT’s business is almost entirely emulsified fuels, with groups that market both to large stationary plants (industrial and utility boilers and gas turbines) and to transportation users (diesel engines). The boiler fuel is typically an emulsified heavy (No. 6) fuel oil, while the turbine and diesel fuels are lighter fuel oils (No. 2, diesel fuel) emulsified with water. CFT has licensed its technologies to different suppliers. Lubrizol markets the diesel fuel as “PuriNOx” fuel nationally, and Global Petroleum is the only current company to market emulsified heavy fuel oil using the CFT technology. The CFT approach is to emulsify the fuel on-site where possible. According to CFT, its technologies can be used to emulsify any heavy petroleum product into a fuel. For some applications (asphalt or refinery bottoms), the emulsification may be required prior to shipment. There are no current applications of this type in the United States.

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Spills of Emulsified Fuels: Risks and Response 100,000 cP). A diluent (kerosene) is added at the wellhead to reduce viscosity and to ease pumping of the bitumen from the production fields to the manufacturing plant. The diluent is separated from bitumen by flash heating. Water from the Morichal River, an alcohol ethoxylate surfactant (AE), and a monoethanolamine stabilizer (MEA) are added to the bitumen and oil components and mixed under high energy to form an emulsion with a viscosity of about 300 cP (similar to a light crude oil). Orimulsion is then readily pumped via pipeline to a coastal terminal for loading onto ships. The Orimulsion formulation was modified in 1998, when BITOR changed the surfactant from nonylphenol ethoxylates, because of concern that these compounds were potential endocrine disrupters and the degradation metabolites were more toxic and persistent than the parent compounds. In addition, magnesium is no longer added. The previous formulation is referred to as Orimulsion-100, and the new formulation is marketed as Orimulsion-400. SPILL RESPONSE ISSUES Following the Oil Pollution Act of 1990, oil spill response has focused on improving the capability to contain and recover spilled oil. Response plans for facilities and vessels have to include sufficient resources that can be deployed effectively to recover specified amounts of oil within a set time (usually 72 hours). Area contingency plans identify priority protection areas and develop site-specific plans to protect the most sensitive resources. Even with this emphasis on preparedness, it is widely accepted in the spill response community that onwater recovery rates of 20 percent of the spilled oil are rarely exceeded. Nearly all of the response plans, strategies, and equipment are based on the assumption that the oil will float. The 1999 National Research Council report Spills of Nonfloating Oils, found that planning for spills of non-floating oil was inadequate, lacking in equipment, response plans, and cleanup methods. To support its own spill response planning, BITOR has implemented special precautions in spill prevention and safety measures, starting in 1994. These measures include the use of only double-hulled vessels both at sea and in rivers and requirements for special procedures and equipment on rivers. The vessels are prescreened through vetting procedures with special criteria. The unique properties and behavior of emulsified fuels suggest that some scrutiny be given to how the response to spills of this type may differ from those of more traditional, floating liquid petroleum products or crude oil. The density of Orimulsion is about 1.01 g/ml at 15°C, which is greater than that of fresh water (=1.00 g/ml) but less than seawater (=1.025 g/ml). The API gravity ranges between 7.8 and 9.3; thus, it is characterized as a Group V oil under U.S. Coast Guard regulations. Spills of Orimulsion pose special issues for spill response because the fuel is essentially predispersed. When spilled into water, the emul-

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Spills of Emulsified Fuels: Risks and Response sion breaks down, releasing the bitumen droplets. Depending on the salinity and currents in the receiving water, these particles can either float, sink, or be kept in suspension. In areas with high concentrations of bitumen, the droplets can recoalesce and rise to the surface, forming tarry slicks. The eventual fate of the bitumen droplets varies according to the spill conditions, although very little recovery of the bitumen particles is likely. ORIGIN OF STUDY Congress, through the FY 1997 appropriations bill, directed the U.S. EPA to initiate research into the qualities and characteristics of Orimulsion and its potential environmental impact. Although not currently used by utilities in the United States, Orimulsion is used in Canada, Japan, China, Italy, and other nations. In response to congressional direction, the EPA studied combustion emissions and control and characterized the risk of Orimulsion use in power plants, including potential impacts of spills. The results of the EPA studies are discussed at length in a recent report to Congress (Miller et al., 2001). Proposals to import Orimulsion into the United States have generated environmental concerns due, in part, to limited information regarding the impact of potential spills. Because of the location of utilities along major rivers and lakes, coupled with the low cost of moving fuel oils by barge, these environments could be exposed to risk in the event of a significant spill. Existing research into the impact and cleanup of spills of emulsified bitumen, however, focuses largely on the marine (saltwater) environment. In an effort to further assess the validity and usefulness of existing literature pertaining to possible spills of Orimulsion, the U.S. EPA and the U.S. Coast Guard requested the National Research Council to undertake a fast-track study to review and evaluate the work on Orimulsion completed to date. Specifically, the sponsors asked that the study “describe the potential environmental impacts of transport-related spills of emulsified fuels, with emphasis on emulsified bitumen, in marine and fresh waters and specify the information needed to evaluate and respond to these risks” (Box 1.1). Furthermore, the committee was asked to “consider relevant literature on transport-related spills of other emulsified fuels, such as emulsified petroleum products. The adequacy of the available research will be assessed and requirements for future research, if any, will be described” and to “determine if specific improvements are needed for response and clean-up of spills of emulsified fuels in both marine and fresh water.” The committee’s evaluation focused on what information was needed to improve oil spill contingency planning and response. Like the NRC (1999) report on the risk and response for non-floating oil spills, the committee looked at the issues from spills of emulsified fuels from a responder’s perspective and the

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Spills of Emulsified Fuels: Risks and Response Box 1.1 Statement of Task This study will describe the potential environmental impacts of transport-related spills of emulsified fuels, with emphasis on emulsified bitumen, in marine and fresh waters and specify the information needed to evaluate and respond to these risks. An overview and analysis of the literature, principally available for Orimulsion (a trademarked product of BITOR), on the potential consequences of such spills will be provided. The study will also consider relevant literature on transport-related spills of other emulsified fuels, such as emulsified petroleum products. The adequacy of the available research will be assessed and requirements for future research, if any, will be described. The final report will determine if specific improvements are needed for response and clean-up of spills of emulsified fuels in both marine and fresh water. standards of preparedness and research that have been applied to oil spill response over the last ten years. The list of literature reviewed during this study, consisting of more than 300 publications, is included in the Reference section and in Appendix B. Most of the research about the behavior of emulsified fuels in water has been funded, or partly funded, by BITOR, and deals only with Orimulsion; work in this area, in partnership with the U.S. Coast Guard and Environment Canada, continues. Additional information on the fate and behavior of polycyclic aromatic hydrocarbons and the surfactants in Orimulsion was also reviewed. The committee found that, of the emulsified fuels, adequate literature to complete its task was available only for Orimulsion. As is common with research directed at a specific product or proprietary process, the overwhelming majority of the available studies were funded by BITOR, the producers of Oriumulsion (or entities interested in using it). This raised some question of the independence and hence the validity of the studies completed. Except where specifically discussed in this report, the committee found the studies to be well executed and documented and to have followed established laboratory practices. Consequently, the committee found no reason to question the validity of the analyses reported. As noted throughout the remaining chapters, the committee did identify areas in which study design and the resulting interpretations should be reexamined and some underlying assumptions reevaluated. Many of the general technical issues raised about Orimulsion during this study have analogues with spills of other emulsified fuels or spills of crude oil or liquid petroleum products. Where possible, the implications of these issues are discussed in terms of general spill effects or responses. However, since much of

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Spills of Emulsified Fuels: Risks and Response the material in the following chapters deals almost exclusively with Orimulsion, careful consideration should be used before any specific conclusions are extended to other emulsified fuels. Based on available literature, the committee developed a number of findings and recommendations that are presented in the following chapters. Environmental factors, such as salinity, affect the behavior of Orimulsion; thus, spills in different environmental settings may provide unique challenges or risks. Although it is beyond the scope of this study to develop quantitative site-specific discussions of the fates and effects of spills of emulsified fuels, six qualitative spill scenarios are presented. Chapter 2 summarizes and evaluates the available literature on the physical and chemical characteristics of Orimulsion as they affect the predicted behavior and fate of the various components once Orimulsion is spilled into water and on land. Similarly, Chapter 3 summarizes, in general terms, various aspects of the potential effects of Orimulsion spills in various environments. Chapter 4 summarizes and evaluates the available proposed response strategies and equipment for responding to Orimulsion spills.