Carbon dioxide release from fossil fuel combustion

Industrial systems are largely dependent on the utilization of fossil fuels, so many environmental effects are due to fossil fuel extraction and combustion. Greenhouse-warming carbon dioxide emissions, acid gas emissions, smog-forming hydrocarbons and nitrogen oxides, and deterioration of atmospheric quality from particles released from fossil fuel combustion are all atmospheric effects associated with fossil fuel combustion. Coal mining activities have the potential to release acid mine water to the hydrosphere, petroleum production can release brines or result in ocean oil spills. 

On the global-scale, the destruction of ozone by halocarbons was addressed in the U.S. by banning chlorofluorocarbons in aerosol products. The release of carbon dioxide to the atmosphere from fossil fuel combustion wil1 continue well into or through the twenty-first century. Energy requirements of nations of the temperate zone will require combustion of gas, oil and coal and the atmospheric burden of carbon dioxide will continue to increase with uncertain consequences. 

In addition to its solvent properties, dense phase fluid carbon dioxide offers the advantage of low toxicity and low potential for environmental harm (the small amounts of greenhouse gas carbon dioxide released from its application as a solvent are negligible compared to the quantities released from the combustion of fossil fuels). A big advantage of dense phase fluid carbon dioxide is its volatility, which means that it separates readily from reaction products when pressure is released. Furthermore, carbon dioxide released from a reaction mixture can be captured and recycled for the same application. Carbon dioxide can be obtained at low cost from biological fermentation processes. 

Seasonal fluctuations are primarily due to summertime maxima and wintertime minima in the net rate of photosynthesis, which removes CO2 from the atmosphere. The long-term trend, however, is clearly upward, and reflects anthropogenic releases of carbon dioxide from fossil fuel combustion, land alteration (in large part, the clearing and burning of tropical forests for agriculture), and, to a lesser extent, cement production. 

Cl -1- O3 CIO + O2. 6 The gas causing an increase in the greenhouse effect is carbon dioxide released by combustion of fossil fuels. It allows most of the Sun s radiation through to the Earth s surface but, when the warm surface gives out infra-red radiation it stops this radiation from escaping into space. Hence, an increase in the concentration of CO2 in the atmosphere makes the atmosphere a better insulating (2)... 

While biomass generally involves the burning of material it differs from fossil fuels in that no more heat or carbon dioxide is produced than would be produced by natural processes. As such, it is referred to as carbon neutral. However, it still produces CO2 and a range of other pollutants including nitrogen oxides, ash, but virtually no SO2. A further environmental benefit is that the combustion of landfill gas avoids accidental explosions and prevents the release of methane, which is more potent as a greenhouse gas. 

The most abundant carbon-containing compound in the stratosphere and mesosphere is carbon dioxide (CO2). By interacting with infrared radiation, this gas plays an important role in the thermal budget of the atmosphere, and the 30% increase in its concentration resulting mainly from fossil fuel burning has provided a significant forcing to the climate system of about 1.5 Wm 2 (IPCC, 2001). Carbon dioxide does not play any substantial role in the chemistry of the atmosphere except in the lower thermosphere, where its photolysis is an important source of carbon monoxide (CO). This latter gas, which is also released at the Earth s surface by incomplete combustion (pollution) and is partially transported to the stratosphere, is converted to CO2 by reaction with the hydroxyl radical (OH). 

There is no doubt that the greenhouse effect is real. The greenhouse effect is a natural occurrence responsible for the current climatic conditions on Earth. Without this natural effect, the Earth s temperature would be about 33°C colder (IPCC 2001). The ultimate question is how the Earth s climate system will respond to the increasing concentrations of greenhouse gases caused by human activities. Atmospheric concentrations of the main greenhouse gas - carbon dioxide - released during the combustion of fossil fuels have increased exponentially from 280 parts per million (ppm) to just over 370 ppm since the Industrial Revolution (IPCC 2001). 

As pollutants go, carbon dioxide might be considered a relatively innocuous component of our atmosphere. After all, every breath we exhale contains about 4% carbon dioxide even though the inhaled air is only about 0.04% carbon dioxide. Fossil fuel combustion and natural decay processes combined with forest and grassland fires release billions of metric tons of carbon dioxide into the atmosphere annually. At the same time, trees, grasses, and other plants remove equivalent quantities of carbon dioxide from our atmosphere each year. Carbon dioxide is constantly being dissolved in and released from the ocean and other bodies of water as their temperature fluctuates. In other words, carbon dioxide is constantly being added to and removed from our atmosphere by a variety of processes, some natural and some of human origin. 

One of the main benefits from future use of biofuels would be the reduction of greenhouse gases compared to the use of fossil fuels. Carbon dioxide, a greenhouse gas that contributes to global warming, is released into the air from combustion. Twenty-four percent of worldwide energy-related carbon emissions in 1997 were from the United States. Carbon... 

Combustion is an oxidation-reduction reaction between a nonmetallic material and molecular oxygen. Combustion reactions are characteristically exothermic (energy releasing). A violent combustion reaction is the formation of water from hydrogen and oxygen. As discussed in Section 9.5, the energy from this reaction is used to power rockets into space. More common examples of combustion include the burning of wood and fossil fuels. The combustion of these and other carbon-based chemicals forms carbon dioxide and water. Consider, for example, the combustion of methane, the major component of natural gas ... 

Worldwide, the amount of energy available from coal is estimated to be about ten times greater than the amount available from all petroleum and natural gas reserves combined. Coal is also the filthiest fossil fuel because it contains large amounts of such impurities as sulfur, toxic heavy metals, and radioactive isotopes. Burning coal is therefore one of the quickest ways to introduce a variety of pollutants into the air. More than half of the sulfur dioxide and about 30 percent of the nitrogen oxides released into the atmosphere by humans come from the combustion of coal. As with other fossil fuels, the combustion of coal also produces large amounts of carbon dioxide. 

Between 1850 and 1998 atmospheric carbon dioxide levels have risen from 285 to 366 ppm, mainly because of the combustion of fossil fuels and changes in land use from forestry to agriculture. This unbalanced release of stored carbon is now generally accepted as setting us on a global climate change journey with an unknown but likely to be unpleasant destination. Combustion of fossil fuels alone contributed 6.3 Gt (gigatonnes or 10 tonnes) of carbon dioxide emissions annually between 1989 and 1998. 

The combustion of fossil fuels releases energy as well. This energy is in the form of heat, and carbon dioxide and water are formed as the bonds in the fossil fuel rearrange themselves during the combustion reaction. Coal, petroleum, and natural gas are known as fossil fuels and are formed from the decay of living matter. 

---