Introduction
Emission of the toxic substance by industries is common all over the world. Toxic substances are emitted daily by industries and anthropogenic activities. Toxic substances are categorized into three categories namely organic, inorganic and metallic compounds. Examples of organic, inorganic and metallic compounds are methane, sulfate and mercury respectively. There have been reports of these substances having negative effects on the environment. Substances like methane are responsible for increased atmospheric temperature. Sulfates affect soil. Sulfates combine with atmospheric water to form acid water. Acid water has a negative effect of soil and microorganism living in it. Mercury, on the other hand, has negative impact water. Increased level of mercury in water affects aquatic organisms (Gregg & Losey et al., 2009).
Industrial emissions in North America vary. North America, especially United States, is considered as one of the main emitters of air pollutants. Emissions in North America can either be inorganic, organic or metallic. Types of waste products emitted by industries are methane, sulfates, mercury and nitrogen dioxide (Gregg & Losey et al., 2009). These pollutants have specific techniques with which they are emitted to the atmosphere. Moreover, industries have techniques used to remove or prevent these pollutants from polluting the atmosphere. Therefore, this essay gives discussion of carbon dioxide, sulfates and mercury and how they affect the atmosphere.
METHANE
Methane is an organic compound that affects the atmosphere when it is emitted from industries as a waste gas. It is the second most emitted greenhouse gas. Methane accounts for 9% of greenhouse gasses accounted in the United States. Since 1990, methane emission in the United States has been decreasing. The figure below illustrates the statistics of its emission from 1990 to 2012.
Figure 1: Methane Emission. Source: United States Environmental Protection Agency, 2014
Damaging/Toxic Effects of Methane
Methane has several damaging effects on the environment and in human health. It is one of the causes of global warming. Research reveals that methane is better in trapping radiation compared to carbon dioxide. Therefore, a large percentage of methane increases atmospheric temperature. Increase in atmospheric temperature leads to a phenomenon known as global warming. Global warming is a gradual increase in atmospheric temperature. This leads to increased floods, occurrence of increased rate of droughts and other natural catastrophes. It also affects animal migration and melting of glaciers leading to rising in sea level which in turn leads to flood and destruction of property (United States Environmental Protection Agency, 2014).
Industrial Process That Creates Methane Emission
Methane is a greenhouse gas. Natural gasses are the main contributors and producers of methane. When petroleum is used in industries, for example, metal industry, combustion leads to release of methane gas as a waste gas or by-product. Methane is emitted in virtually all industrial processes. Its emission is mainly as a result of it being a constituent of petroleum and natural gas. Methane is also produced by animals. Domestic animals produce a large amount of methane while digesting food. Moreover, during manure production, large amounts of methane are released into the atmosphere. Therefore, the agricultural sector is considered as one of the main sources of methane emission (United States Environmental Protection Agency, 2014).
Methods Used By Industries to Reduce or Eliminate Methane Emissions
Natural gas and petroleum are regarded as the main sources of methane emissions. In order to reduce the rate of methane emissions, industries are resorting to the application of effective methods of transportation. As stated earlier, the main source of methane is petroleum and natural gasses. Therefore, good transportation methods of petroleum and natural gas reduce emission of methane gas into the atmosphere. Secondly, industries are installing technologies that capture methane production. Methane is captured by these technologies and then reused. These technologies are pneumatics, dehydrators, plunger lifts, vapor recovery units, rod packing, composite wrap and pipeline pump down (Kevin & Roger, n.d.).
Pneumatic devices are bleeding sources of petroleum. Therefore, in order to reduce methane emission, other pneumatic devices need to be used alongside the main ones. In essence, an efficient pneumatic device ensures that a small portion of methane is bled into the atmosphere. Dehydrators are used in processing of triethylene glycol from methane. In order to reduce methane emissions, tank separators can also be used. Tank separators have the ability of reducing 90% of methane emission. It prevents methane from being transmitted into the atmosphere. Plunger lifts reduce emission of methane into the atmosphere by channeling methane gas situated in gas wells to storage tanks. During fluid removal in gas production, methane tends to leak to the atmosphere. Plunger lifts prevent this methane (from the wells) from leaking into the atmosphere by channeling it into storage tanks (Kevin & Roger, n.d.).
Other than processing of natural gas, storage of the same also leads to release of methane into the atmosphere. Methane released due to storage of petroleum, and natural gas can be reduced by the use of vapor recovery units. Vapor recovery units remove air in storage tanks. It then channels it to a scrubber (Kevin & Roger, n.d.).
During the transmission of natural gas, a large percentage of methane is leaked into the atmosphere. Rod packing is used to reduce the amount of leaks during transmission. Rod packing is considered one of the best techniques of reducing gas leaks. Replacement of wet compressor seals is also one of the techniques industries are using to reduce gas leaks. Pipeline pump down is also used to reduce methane leak. Pump down techniques is used to reduce gas pressure inventing pipes. Pump down is done by using in-line compressors and portable compressors (Kevin & Roger, n.d.).
Natural gas is regarded as the main source of methane emissions. Industries are resorting to using methane free sources of energy. Some of these methane free sources of energy are solar energy, geothermal and wind power. These energies do not release methane thus they are efficient in reducing carbon dioxide emissions. Most companies in the United States are resorting to geothermal power to run their industries. Some industries are also trying to harness hydropower and nuclear energy. Use of these fuels reduces methane emissions into the atmosphere (United States Environmental Protection Agency, 2014).
SULFATE (SO4)
Unlike Carbon dioxide, sulfate is not a common pollutant of the environment. Sulfate is released from combustion of sulphur dioxide. It has microscopic particles. Sulfur dioxide is emitted after combustion of fossil fuels. The emission of sulfur dioxide into the atmosphere leads to the formation of sulfate compounds since sulfur dioxide is not stable. It readily reacts with moisture in the presence of oxygen to form sulfate compounds. These compounds are majorly acidic hence harmful to the environment. Combination with oxygen leads to the formation of sulfate products. Sulfate is comprised of sulfur and 4 oxygen molecules (Hand et al., 2012; Lajtha & Jones, 2013).
Damaging/Toxic Effects Sulfate
Industrial emission of sulfate has negative effects on the environment and human health. Sulfate aerosols reduce climate temperature. It does this by reflecting radiated particles and influencing the formation of clouds. Sulfate aerosols absorb solar radiations. It prevents radiations from reaching the earth. This causes the cooling effect on the earth surface affecting wildlife. Sulfate aerosols that also lead to the formation of acidic compounds. Sulfate combines with atmospheric vapor to form acid rain. Acid rain affects growth of plants, corrodes rooftops and destroys micro-organisms in the soil. Furthermore, sulfate causes lung irritation. It also causes ground level haze (Hausefather, 2008).
Industrial Process That Creates Sulfate Emission
Sulfate aerosol is formed when sulfur dioxide combines with oxygen. Sulfur dioxide is formed when sulphur from fossil fuels combines with oxygen to form sulphur dioxide. Sulphur dioxide is further burnt to release sulfate (Hand, et al., 2012).
Methods Used By Industries to Reduce or Eliminate Sulfate Emissions
Industries use different techniques to reduce emission of sulfate into the atmosphere. The first technique is called fuel switching and scrubbing. Fuel switching is a concept that involves the use of fuels that have a low level of sulfur (Zhang et al., 014). Moreover, one can use fuels that do not contain sulfur. Scrubbing, on the other hand, involves eliminating sulfur and sulfates from products. Removal of sulfur leading to the formation of sulfates is done through electrostatic or chemical processes. Electrostatic process entails using of electronically charged plates on industry stack. The charge from electricity helps to dislodge sulfur from the stacks. Positively charged sulfur usually attaches to the charges. In such a situation, sulfur is eliminated before it enters into the atmosphere (World Bank Group, n.d.).
Dry scrubbing can also be used to remove sulfates from the environment. Some industries use dry scrubbing to reduce emission of sulfates into the atmosphere. Dry scrubbing involves use of chemicals to eliminate sulfur in blocks. When sulfur has been removed from blocks, it should be properly disposed. Improper disposal will cause pollution. Industries also use technologies to filter sulfur and sulfates. Some of the technologies used are sorbent injection and flue gas desulfurization. Sorbent injection entails addition of alkali compound to gasses emitted due to combustion of fossil fuels. Types of sorbents used have calcium and lime. The sorbents remove sulfur dioxide which forms sulfate aerosol. Removal of sulfur dioxides aids in a reduction of sulfate emission into the atmosphere. Flue gas desulfurization, on the other hand, entails the use of regenerable and throw away. Throwaway systems employ the use of scrubbing mediums. These mediums are cheap compared to regenerable systems (World Bank Group, n.d.).
MERCURY
Industrial emission of mercury in North America has been steadily rising. Since 1970s research shows that industrial emissions of mercury have risen considerably. Significant increases were noted in 2000 and 2005. Currently, the rate of mercury emission into the environment has decreased because of prevention measures instituted by most companies. Mercury emission is high in power plants.
Damaging/Toxic Effects Mercury
Mercury has serious damaging effects on the environment and humans. When mercury combines with methyl, it forms methyl mercury. Methylmercury is considered one of the most dangerous chemicals in the world. High exposure of mercury leads to a reduction of the immune system. Moreover, genetic and enzymes systems are changed as a result of mercury intake. Nervous system is also affected. Sense of touch, smell and taste is generally impaired when mercury is present in the body. Moreover, a large amount of mercury in the environment leads to damage of developing embryos. High intake of mercury-contaminated seafood or fish by pregnant women affects embryo development. Children born of mothers having high levels of mercury in their bodies are likely to suffer from nervous problems. Large amounts of mercury have neurodevelopment effects on unborn children (U.S. Geological Survey, 2009).
Emission of mercury to the atmosphere has an effect on fish and wildlife. A large percentage of mercury in the environment affects production system of wildlife. Research carried out in Wisconsin reveals that high levels of mercury emission into the environment affected loon chick production. This is because the percentage of mercury in lakes and eventually chick eggs was high. Furthermore, high level of mercury in sea water affects growth and behavior of bird-like egrets. Significant levels of mercury affect protective enzymes of this bird. Because of a large percentage of mercury, protective enzymes of egrets fail to function well. Heron embryos are also affected by high levels of mercury in water sources especially the sea. Mercury can also lead to deformities (U.S. Geological Survey, 2009).
Industrial Process (Es) That Creates Mercury Emission
Power plants are the main emitters of mercury in the United States. Power plants release 33 tons of mercury each year. Power plants contribute more than half of all emissions produced in North America. Mercury emissions are as a result of coal-fired power plants. During gold mining, mercury is used to remove gold from its ore. During mining, the ore is burnt leaving mercury behind. This releases a significant amount of mercury into the atmosphere. Mercury can also be retrieved from metal ores. These ores can be used to manufacture cement. Mercury is also produced when chlorine is manufactured. Mercury is a constituent of many products, for example, batteries. When these products are disposed, mercury is released into the atmosphere (Mercury, 2014).
In addition, mercury is released to the environment when fossil fuels are burnt. Coal has a small percentage of mercury. A small portion of it cannot release dangerous amounts of mercury to the environment. However, when large amounts of coal are burnt a significant portion of mercury is released to the environment. Mercury is also a constituent of petroleum fuels. When petroleum is being processed, mercury is removed before processing. However, large amounts of it will carry a significant amount of mercury. Mercury is present in wastes. Therefore, landfills cause pollution of underground or surface water (Mercury, 2014).
Methods Used By Industries to Reduce or Eliminate Mercury Emissions
Companies use different techniques to eliminate or reduce the amount of mercury emitted into the environment. The first method used by industries is reduction in the use of raw materials that cause emission of mercury into the atmosphere. Industries are now opting to use of raw materials that do not have mercury or have a low content. Some industries are now using alternative sources of energy, for example, natural gasses. Industries are opting to use this instead of coal. On the contrary, some industries are using coal that has a lower percentage of mercury. Secondly, companies are producing products that do not have mercury as a constituent. This method is called substituting products. This is whereby industries make the decision of producing products that do not have traces of mercury. This helps to reduce the amount of mercury reaching consumers (Mercury, 2014).
Thirdly, some companies use end-of-pipe methods. End-pipe techniques are the use of exhaust gas filtering. This technology reduces and eliminates the amount of mercury released into the atmosphere. The technologies filter mercury as it is released from the manufacture of steel and cement. Waste management is also a good method of reducing industrial mercury emissions. Research states that some companies release waste products into the environment. These waste products have a certain amount of mercury. When wastes encounter water, mercury mixes with it causing contamination of water (Mercury, 2014). In such a situation waste incinerators are used to reduce mercury emission from industrial waste products (Mercury, 2014).
Industries also use pre-combustion and cleaning methods. These methods are common to industries that burn coal. Stack gas cleaning is a technique that can be used to reduce industrial mercury emission. Anti-Lock brake systems are also used by some industries. Switch or removal programs are also used (Mercury, 2014).
Conclusion
Industries release different pollutants into the atmosphere. Some of the pollutants are methane, mercury, and sulfate. North America is one of the largest emitters of industrial pollutants. The continent produces large portions of methane, mercury, and sulfates. Methane is a common pollutant emitted when natural gas is stored and transported. It has negative effects on the environment. Methane gas causes global warming which in turn causes detrimental effects to the environment. An increase in methane level above the normal creates insulation in the lower atmosphere. Methane insulation prevents reflected earths rays from reaching upper atmosphere. Industries reduce emission of carbon dioxide by using alternative sources of fuel. It can also be reduced by introduction of technologies. Some of the technologies used are pneumatics, dehydrators, plunger lifts, vapor recovery units, rod packing, composite wrap and pipeline pump down. Pneumatic devices are bleeding sources of petroleum. Therefore, in order to reduce methane emission, other pneumatic devices need to be used alongside the main ones.
Mercury is also emitted by industries in North America. Industrial emission of mercury in North America has been steadily rising. Since 70s research shows that industrial emissions of mercury have risen considerably. Mercury has negative effects on human health and environment. Fetus development is affected by high intake of mercury. Moreover, nervous system is interfered with. Currently, the rate of mercury emission into the environment has decreased because of prevention measures instituted by most companies.
On the other hand, Industrial emission of sulfate has negative effects on the environment and human health. Sulfate aerosols reduce climate temperature. It does this by reflecting radiated particles and influencing the formation of clouds. Sulfate aerosols absorb solar radiations. It prevents radiations from reaching the earth. This causes the cooling effect on the earth surface affecting wildlife. Sulfate also aerosols lead to the formation of acid rain. Sulfate combines with atmospheric vapor to form acid. Acid rain affects growth of plants, corrodes rooftops and destroys micro-organisms in the soil. Furthermore, sulfate causes lung irritation. It also causes ground level haze.
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