SOLAR ENERGY TECHNOLOGY BREAKTHROUGH!

Wind Power

Showing posts with label smog. Show all posts
Showing posts with label smog. Show all posts

Sunday, March 23, 2008

Pollution from Oil refineries:

Pollution from Oil refineries:

Oil refineries pollute our air, water, and land. Oil refineries cause smog and air pollution. Almost all refineries in every country currently pollute at unacceptable, unhealthy levels. Oil refineries emit about 100 chemicals everyday. These include metals like lead which makes it hard for children to learn. They also include very smaller size dust particles that get deep into our lungs and harm our ability to breathe. Finally, refineries emit many gases like sulfur dioxide (SO2), nitrogen oxide (NO2), carbon dioxide, carbon monoxide, methane, dioxins, hydrogen fluoride, chlorine, benzene and others.

Many of the gases emitted by refineries are harmful to humans, and can cause permanent damage and even death. They can cause respiratory problems (such as asthma, coughing, chest pain, choking, bronchitis), skin irritations, nausea, eye problems, headaches, birth defects, leukemia, and cancers. Young children and the elderly are the worst affected.

Sulfur dioxide (SO2): Crude oil and coal both contain relatively high quantities of sulfur. (Natural gases contain much less sulfur and therefore are safer.) When crude oil or coal is heated at the refinery to produce fuel, the sulfur is converted into a gas called sulfur dioxide. This is a colorless gas with a very strong smell, like rotten eggs.

Bad effects of Sulfur dioxide: Exposure to very high concentrations of SO2 can result in painful irritation of the eyes, nose, mouth and throat, difficulty in breathing, nausea, vomiting, headaches and even death. Some of the health effects from daily exposure to outdoor levels of SO2 are tight chests, worsening of asthma and lung disease, and narrowing of air passages in the throat and chest. People with asthma are more sensitive to SO2. Exposure to SO2 can provoke asthma attacks. SO2 mixes easily in water, including moisture in the air to form an acid. Acid rain and early morning dew causes much damage to metals, stones, and the environment.

Fugitive emissions are the air pollution which escapes through leaks in the equipment. Very often the amount of pollution coming from fugitive emissions is higher than the amount coming out of the stacks.

Many of the refineries often use low quality crude oil that has high levels of sulfur. When this is refined it produces higher levels of SO2 pollution.

Accidental fires, explosions, and chemical and gas leaks are common at refineries. Such accidents cause higher than usual amounts of pollution, which may result in more acute exposure to pollutants and greater health impacts.

Thursday, January 31, 2008

Mechanism of Adverse Impact of Smoke Pollutant

Mechanism of Adverse Impact of Smoke Pollutant:

The main sources of smoke pollutants in urban areas are Petrol / Diesel driven motor vehicles, Fuel combustion in stationary sources including residential, commercial and industrial heating / cooling system and coal-burning power plants etc.

Petrol / Diesel driven motor vehicles produce high levels of Carbon Dioxide (CO2) / Carbon Monoxide (CO), major source of Hydrocarbon (HC) and Nitrogen oxides (NOx). Fuel combustion in stationary sources is the dominant source of Carbon Dioxide (CO2) and Sulfur Dioxide (SO2).

Carbon Dioxide (CO2) – This is one of the major gas pollutants in the atmosphere. Major sources of CO2 are due to burning of fossil fuels and deforestation. Industrially developed countries like USA, Russia etc., account for more than 65% of CO2 emission. Less developed countries with 80% of world’s population responsible for about 35% of CO2 emission. Due to high growth reported from less developed countries in last decade, it is estimated that, the Carbon dioxide emissions may rise from these areas and by 2020 their contribution may become 50%. It has also been seen that, Carbon dioxide emissions are rising by 4% annually.

As ocean water contain about 60 times more CO2 than atmosphere; CO2 released by the industry leads to disturbance of equilibrium of concentration of CO2 in the system. In such a scenario, the oceans would absorb more and more CO2 and atmosphere would also remain excess of CO2. As water warms, ocean’s ability to absorb CO2 is reduced. CO2 is a good transmitter of sunlight, but partially restricts infrared radiation going back from the earth into space. This produces the so-called “Greenhouse Effect” that prevents a drastic cooling of the Earth during the night. This so-called “Greenhouse Effect” is responsible for GLOBAL WARMING. Currently Carbon Dioxide is responsible for major portion of the global warming trend.

Nitrogen oxides (NOx) - They come mainly from nitrogen based fertilizers, deforestation, and biomass burning. Nitrogen oxides contribute mostly as atmospheric contaminants. These gases are responsible in the formation of both acid precipitation and photochemical smog and causes nitrogen loading. These gases have a role in reducing stratospheric ozone.

Sulfur Dioxide (SO2) - Sulfur dioxide is produced by combustion of sulfur-containing fuels, such as coal and fuel oils. SO2 also produced in the process of producing Sulfuric Acid and in metallurgical process involving ores that contain sulfur. Sulfur oxides can injure man, plants and materials. As emissions of sulfur dioxide and nitric oxide from stationary sources are transported long distances by winds, they form secondary pollutants such as nitrogen dioxide, nitric acid vapor, and droplets containing solutions of sulfuric acid, sulfate, and nitrate salts. These chemicals descend to the earth's surface in wet form as rain or snow and in dry form as a gases fog, dew, or solid particles. This is known as acid deposition or acid rain.

Choloroflurocarbons (CFCs) - Chlorofluorocarbons, also known as Freons, are greenhouse gases that contribute to global warming. CFCs are responsible for lowering the average concentration of ozone in the stratosphere.

Smog – Smog is the result from the irradiation by sunlight of hydrocarbons caused primarily by unburned gasoline emitted by automobiles and other combustion sources. Smog is created by burning coal and heavy oil that contain mostly sulfur impurities.