hazardous air pollutant studies conducted by DOE from 1990 through 1995, with some efforts through 1997. The overriding finding of these studies was that mercury is not effectively controlled in coal-fired utility boiler systems. EPA also concluded that a plausible link exists between these emissions and adverse health effects. The ineffective control of mercury by existing coal technologies was due to a number of factors, including variation in coal composition and resulting variability in the form of the mercury in flue gases. The volatility of mercury was the main reason for less removal. In addition, it was determined that there was no reliable mercury specification method to accurately distinguish between the elemental and oxidized forms of mercury in the flue gas, which act differently with respect to their removal by the air pollution control devices utilized by the coal-fired utility industry.

MHD:

Magnetohydrodynamics is a means of producing electricity directly by moving liquids or gases through a magnetic field.


natural gas:

A mixture of gaseous hydrocarbons, composed primarily of methane and occurring naturally in the earth, often among petroleum deposits. It is used as fuel.

NOx:

Oxides of nitrogen; a mix of nitrous oxide (NO) and nitrogen dioxide (NO2).

NOxcontrol:

Techniques for reducing NOx emissions from fossil-fuel-fired boilers can be classified into two categories: combustion controls and postcombustion controls. Combustion controls reduce NOx formation during the combustion process, while postcombustion controls reduce NOx after is has been formed.


O3:

Ozone is a bluish, toxic gas with a pungent odor. It is formed by three oxygen atoms rather than the usual two. Ozone occurs in the stratosphere and plays a role in filtering out ultraviolet radiation from the sun’s rays. At ground level, ozone is a major component of smog.

OAPEC:

The Organization of Arab Petroleum Exporting Countries was established in 1968 with permanent headquarters in Kuwait. It is an instrument of Arab cooperation whose objective is to provide support to the Arab oil industry. Its activities are developmental in nature, and its membership is restricted to Arab countries with oil revenues that constitute a significant part of their GNPs.

OPEC:

The Organization of Petroleum Exporting Countries, founded in 1960 to unify and coordinate the petroleum policies of the members. The headquarters is in Vienna, Austria.

oxy-fueled glass furnace:

The glass industry is a large user of energy in furnaces to produce glass containers, float glass for windows in construction and automobiles, fiber glass insulation, and other specialty products. The high temperatures required for glass manufacture and the raw materials used in glass result in significant emissions of NOx and particulates. The oxy-fuel furnace substitutes oxygen for air in the combustion process. This change in the process significantly reduces NOx emissions, reduces the amount of energy required per ton of glass produced, reduces levels of other gases, and reduces the capital costs for furnace regenerators and emissions control equipment.


P-4:

The Programmable Powdered Preform Process is a way of fabricating a preform that is essentially the fibrous skeleton of a composite structure. Chopped reinforcement fibers and resin powder are simultaneously sprayed onto a heated screen mandrel by robots that control the placement, depth, and orientation of the fibers. The resin powder melts, causing the fibers to stick together enough for the preform to be removed whole from the mandrel. The preform is placed in a mold, where it is infused with more resin, compressed, and heat-cured to form the final product. P-4 is highly automated and results in finished parts with good dimensional stability, strength, and corrosion and wear resistance. It is also much faster than most composite preform processes.

peak load:

Peak load (usually in reference to electrical load) is the maximum load during a specified period of time. Peak periods during the day usually occur in the morning hours from 6 to 9 A.M. and during the afternoons from 4 P.M. to about 8 or 9 P.M. The afternoon peak demand periods are usually higher, and they are highest during summer months when air-conditioning use is the highest.

PEM fuel cell:

A PEM (proton exchange membrane, also called polymer electrolyte membrane) fuel cell uses a simple chemical process to combine hydrogen and oxygen into water, producing electric current in the process.

PFBC:

Pressurized fluidized-bed combustion is one of several advanced approaches for substantially improving the efficiency of coal-fired power systems while significantly reducing emissions. In contrast to the atmospheric fluidized-bed combustion (AFBC) system, in a PFBC system, the boiler, cyclones, and other associated hardware are encapsulated in a pressure vessel. This compact “boiler in a bottle” is about one-fourth the size of a pulverized coal boiler of similar capacity. PFBC units are intended to give an efficiency value of over 40 percent and low emissions, and developments of the system using more advanced cycles are intended to achieve efficiencies of over 45 percent.

PNGV:

Partnership for a New Generation of Vehicles was established in September 1993 as a collaboration between the federal government and the United States Council for Automotive Research (USCAR), which represents DaimlerChrysler, Ford, and General Motors. The PNGV’s goal is to develop technologies for a new generation of energy efficient and environmentally friendly vehicles.



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