Health Effects Of Exposure To Indoor Smoke

indoors smoke
Exposure to indoor air pollution from the combustion of solid fuels has been implicated, with varying degrees of evidence, as a causal agent of several diseases in developing countries. In a review of the epidemiological evidence for the health effects of indoor smoke from solid fuels, Bruce et al. concluded that, despite some methodological limitations, epidemiological studies provide compelling evidence of causality for acute respiratory infections (ARI) and chronic obstructive pulmonary disease (COPD). This is reinforced by experimental data, studies of pathogenesis, and indirect evidence from environmental tobacco smoke (ETS) and ambient air pollution studies. (more…)

Primary Energy Use and Clean Coal Technology

clean coal technology
Transportation is another sector that has increased its relative share of primary energy use. This sector has serious concerns as it is a significant source of CO2 emissions and other airborne pollutants, and it is almost totally based on oil as its energy source. An important aspect of future changes in transportation depends on what happens to the available oil resources, production and prices. At present, 95% of all energy for transportation comes from oil. (more…)

Acid Deposition Effects: Aquatic and Terrestrial Acid Rains

Effects Of Acid Deposition
Acid deposition and the associated particulate nitrates and sulfates are implicated in the deterioration of certain sensitive ecosystems, decreased visibility, negative human health effects, and increased degradation of certain stone building materials and cultural resources, especially those made of limestone and marble. Fine particulate nitrate and sulfate particles associated with acid deposition are implicated in aggravating cardiorespiratory diseases such as asthma and chronic bronchitis, especially in urban areas. In many cases estimating the impact of acid deposition on various ecosystems can be a difficult process because acid deposition is only one of many impacts that can effect a response. However, wet and dry acid deposition has been documented as a major factor in the following ecosystem responses. (more…)

Chemical Pulp Paper Production

More than 48% of the raw material fiber used for paper production (chemical pulp or mechanical pulp) in the United States in 2002 was recovered or reclaimed, with recovered paper contributing 37.7% and wood residues 10.6%. The total has been more or less constant, with the percentage of recovered paper increasing and that of wood residues declining recently due to their increased use in oriented strand board and composite panels. Primary fibers are a renewable, domestic resource, much of which is currently supplied by tree plantations. Short-rotation forestry can be used to further increase the productivity of these plantations. (more…)

Intergovernmental Panel on Climate Change: Why Is Global Warming a Problem?

Although some scientists and critics still dispute that human caused greenhouse gases are causing climate change, the majority of scientists and climate experts assert that global warming is a serious problem that could have devastating consequences unless action is taken to reduce fossil fuel emissions. In 2007, for example, the Nobel Prize–winning Intergovernmental Panel on Climate Change (IPCC), a scientific body charged by the United Nations with summarizing the best climate science, concludes that evidence of the warming of our climate is “unequivocal.” (more…)

CO2 Emission Reduction and Fossil Fuels Carbon

Reductions in carbon intensity, C/E, the carbon emitted per unit of energy generated, reflect the degree to which societies decarbonize their energy sources. The long-term trend has been a shift from coal to oil to natural gas––hydrocarbons with decreasing C/H ratios emitting progressively less CO2 per joule. However, the increasing use of clean low-carbon fuels is not sustainable without somehow disposing of excess carbon because it opposes the trend in the abundance of fossil fuels, with coal resources being the most abundant followed by oil and gas. (more…)

Circulating Fluidized Bed Gasification Biomass Feedstock

Air-blown circulating fluidized bed gasifiers are of interest because they produce a good quality, low calorific value (LCV) gas (4–6 MJ/Nm 3 ) and possess a very high carbon conversion efficiency while allowing high capacity, good tolerance to variations in fuel quality, and reliable operation. The high and homogeneously distributed temperatures and the use of particular bed materials, such as dolomite, favor tar cracking. Successful tar cracking can also be achieved using secondary circulating fluidized bed reactors. Also, successful tests on catalytic tar cracking have been performed, for example, by introducing nickel compounds into the gasifier. Sulfur control is made easier because of the significant reduction that can be achieved by adding limestone or dolomite to the gasifier bed. (more…)

Solutions to Energy-Related Global Warming

Addressing global warming, however, is a highly complex and daunting endeavor. Many climate experts have urged the world to stabilize greenhouse gas concentrations in the atmosphere around 450 to 550 parts per million (ppm)—that is, no more than 450 to 550 units of greenhouse gases for every million units of air in the earth’s atmosphere. This approach, experts say, could keep average global temperatures at no more than 3.6° Fahrenheit (2° Celsius) above preindustrial levels, which could avoid some of the worst, irreversible consequences of climate change. (more…)

Strategies for Confronting Climate Change

Options for dealing with the threats of climate change include both adaptation to inevitable changes and mitigation, or lessening, of those changes that we can still affect. One possible adaptation would be to adjust our agricultural practices to the changing regional patterns of temperature and rainfall. Another would be to build coastal defenses against the inundation from sea-level rise. Only mitigation, however, can prevent the most threatening changes. (more…)

Dependence on Fossil Fuels: The Fossil Fuel Era

The global dependence on fossil fuels developed during the Industrial Revolution, two centuries of economic and social development that transformed the way modern humans work and live. Most historians agree that the Industrial Revolution began in the early 1700s in Great Britain when machinery began to replace manual labor and animal power, and fossil fuels replaced wind, water, and wood as main energy sources. Before this period in history, humans manufactured goods by hand or using very simple machines, and most people worked at their homes, which were typically located in rural areas. (more…)

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