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[en] High-resolution Fourier-transform IR (FTIR) absorption spectroscopy is presently used over open paths in biomass-fire smoke plumes to remotely sense emissions. FTIR can be employed in simultaneous measurements of a wide range of gas-phase species. Measurements are integrated over a long path through the smoke plume, and are therefore not subject to small-scale local variations. The emissions of all nitrogen species from the four field fires studied can be compared to the nitrogen content of the fuels burned; valuable insight has been gained into the relationships between biomass burning emissions and fire parameters

[en] Emissions of trace gases, particles, and air toxic substances in the smoke plumes from biomass fires are of importance to global climate change. The potential impact of the air toxic emissions on the human population of specific regions globally is another major concern. The toxic materials are produced in high concentrations in areas of heavy biomass burning, e.g., Amazon Basin and Central/southern Africa. We provide new estimates of air toxics based on the combustion efficiency (percent of total carbon released as CO₂) for fires burning in different ecosystems on a global basis. Estimates of total biomass consumed on a global basis range from 2 to 10 Pg (1 petagram = 10¹⁵g) per year. We apply emission factors for various air toxics (g of emission released per kg of fuel consumed) to the estimate of global biomass consumption of 6.4 Pg per year. The principal air toxics analyzed in this paper include: Total particulate matter, CO, formaldehyde, acetaldehyde, acrolein, benzene, toluene, o-xylene, m, p-xylene, benzo[a]pyrene, and polycyclic organic material. The total emissions calculated for these materials on a yearly global basis are: 75, 362, 4.9, 1.5, 1.5, 2.1, 2.1, 0.3, 0.6, 0.001, 0.026, Tg (1 teragram = 10¹²g) per year, respectively. Biomass burning in the United States contributes less than 3% to the total global emissions

[en] A new tritium processing facility, named the Replacement Tritium Facility (RTF), has been completed and is being prepared for startup at the Savannah River Site (SRS). The RTF has the capability to recover, purify and separate hydrogen isotopes from recycled gas containers. A multilayered confinement system is designed to reduce tritium losses to the environment. This confinement system is expected to confine and recover any tritium that might escape the process equipment, and to maintain the tritium concentration in the nitrogen glovebox atmosphere to less than 10^-2 μCi/cc tritium

[en] The reaction of hydrogen isotopes with the storage bed hydride material is exothermic during absorption and endothermic during desorption. Therefore, storage bed operation requires a cooling system to remove heat during absorption, and a heating system to add the heat needed for desorption. Three storage bed designs and their associated methods of heating and cooling and accountability are presented within. The first design is the current RTF (Replacement Tritium Facility) nitrogen heating and cooling system. The second design uses natural convection cooling with ambient glove box nitrogen and electrical resistance for heating. This design is referred to as the Naturally Cooled/Electrically Heated (NCEH) design. The third design uses forced convection cooling with ambient glove box nitrogen and electrical resistance for heating. The design is referred to as the Forced Convection Cooled/Electrically Heated (FCCEH) design. In this report the operation, storage bed design, and equipment required for heating, cooling, and accountability of each design are described. The advantages and disadvantages of each design are listed and discussed. Based on the information presented within, it is recommended that the NCEH design be selected for further development

[en] Results are presented of a continuing study of research that was started in 1988. A new sampling system was designed to provide fire dynamics data from within the fire. This chapter describes the sampling system, the measurements it provided on one biomass fire, and some valuable parameters that can be calculated such as emission factors, combustion efficiency, and rate of fuel consumption. The large prescribed fire in Ontario, Canada, provided a practical test of this package that can be used to assess the application of the monitoring concept to a broad range of biomass fires. Measurements of wind vectors, temperature, and emissions of CO₂, CO and particulates are reported for a 40-minute period from ignition through the critical period of maximum release of heat to the near extinction of the smoldering combustion phase

[en] Fires are widely used for various land use practices in tropical countries. Large amounts of trace gases and aerosol particles are produced during the fires. It is important to assess the potential impact of these gases and particulate matter on the chemistry of the atmosphere and global climate. One of the largest uncertainties in quantifying the effects is the lack of information on the source strengths. The authors quantify the amount of biomass burned due to deforestation in each tropical country on basis of the deforestation rate, the above ground density, and the fraction of above ground biomass burned. Approximately 725 Tg of biomass were burned in 1980 and 984 Tg were burned in 1990. The 36% increase took place mostly in Latin America and tropical Asia. The largest source was Brazil, contributing about 29% of the total biomass burned in the tropics. The second largest source was Indonesia accounting for 10%, followed by Zaire accounting for about 8%. The burning of biomass due to increased deforestation has resulted in an additional 33 Tg CO and 2.5 Tg CH₄ emitted annually to the atmosphere from 1980 to 1990

[en] In this chapter the authors report results from a study that was designed to derive an estimate of the total release of important pollutant species from a well-characterized fire. Ground and aircraft measurements were coordinated to yield a relatively complete picture of fire behavior and accompanying smoke production. Results from these measurements are then integrated over the lifetime of the fire and compared to less rigorous methods of estimating pollutant yield. Results suggest that knowledge of fuel consumption by phase of combustion (flaming vs. smoldering) is important in making accurate estimates of the characteristics of smoke emissions from individual fires. Contributing factors such as fuel type, fuel loading, and meteorological history vary significantly by region and should be taken into account when compiling estimates of fuel consumption rates during both flaming and smoldering fire conditions

[en] Fires in savanna ecosystems are usually considered to be ''natural'' in that the ecosystems where fire is present generally have evolved in the presence of fire. In the past several decades, with large increases in population in most of the tropical countries, there has been an accelerated demand for fuel wood, charcoal, building materials, and agriculture. The overall effect has been to reduce the above-ground biomass and to cycle the carbon more frequently. The authors discuss the mitigation strategies for reducing the release of carbon from charcoal production and shifting cultivation

[en] An airborne sampling system was used to collect grab samples of smokes for analysis of both in-plume smoke characteristics and ambient air in Brazil. In addition to the emission measurements, the chemical composition of the forest biomass burned by one fire in the Amazon region of Brazil was compared to the fuel composition for biomass burned in North America. The limited data set suggests that combustion efficiencies for tropical biomass combustion are higher than those of temperature forest fuels, as are emission factors for carbon dioxide