Fracking or hydraulic fracturing is a proven work of technology for natural gas extraction for deep formations of shale. This is quite a safe method for procuring natural gas. This method can significantly reduce Carbon dioxide emissions and it can help in making a carbon free environment in future. The easy access to natural gas can also ensure that any nation with natural gas reserves can make use of it without any need for imports from other countries. This method of fracking can help in meeting the energy demands of a country and make it economically more stable.
In the process of fracking hard shale rock deposits are fractured to release the natural gas inside it. A well is drilled and a steel casing is inserted with many perforations into the target zones. Once the fracking liquid is pumped through the casing, the liquid stars filling up in the target zones until it gets saturated. At this point pressure starts building up at the target zones, tiny explosions are created due to this pressure thus fracturing or breaking the rocks by drilling deep down. A mixture of water, sand and some more chemicals are used for injection into the drill. The sand and chemiclas used in here are called the proppants which helps in keeping the fissures open while the gas escapes. They are injected at high pressure and that forces the gas out from the mouth of the well. The process is carried out vertically but the horizontal rock layers can also be drilled. With this process new channels can be created for the release of gas and the existing channels can be made longer.
In this mixture of fracking liquid sand and fresh water is 98% of the total. The remaining 2% consist of different kinds of chemicals like breakers(peroxydisulfates), acid(hydrochloric acid), antibacterial agent(Gluteraldehyde and 2-Bromo-2-nitro-1,2-propanediol), clay stabilizer, cross linker, corrosion inhibitor, friction reducer, gelling agent, pH adjusting agent, iron control, surfactant, and scale inhibitor. The water is used in order to open the drills and inject sand into it. The sand used in the fracking liquid is useful for keeping the fractures caused open so that the natural gas can come out. The acid is used for neutralization, and the antibacterial agent is used to kill bacteria in order to avoid the production of corrosive gases.
Lately due to the negative impacts Fracking other methods are being considered which might reduce the pollution of ground water and reduce the amount of water used in Fracking. LPG or Liquid Propane gas has been developed in Canada and is being studies in US. In this method instead of water, LPG is used and is a waterless method. LPG is the cooking gas we all know about and use in barbecue grilling outdoors. The LPG is a thick gel which is pumped similar to water into the shale rock which creates an intense pressure that cracks the shale releasing the natural gas trapped inside. The LPG however goes into the ground where it is converted into vapordue to the heat below and returns back to the surface with the natural gas and can be reused. One of the advantages of using LPG hers is unlike water it does not release the seabed salts and other pollutants from the soil back to the surface. The using of gas versus water has the added advantage of helping the environment since the water method has a lot of chemical polluted water that is released back into the environment, the gas does not do this and thus reduces both drilling costs and cleaning up costs. So why this technology hasn't been gaining popularity could be mainly attributed to habit in the way od sing the same industrial methods without looking for better alternatives and higher costs of the waterless method. But this might help in the long run in reducing negative impacts on the environment.
In the year 2010 U.S.A’s Environmental Protection Agency estimated that 70 to 140 million liters of water are being used in the hydraulic fracking liquid to open 35,000 natural gas wells. This is a huge quantity of water that can supply 40 to 80 cities with 50,000 populations. Coal bed methane gas wells use less water but the horizontal shale wells use a huge quantity of water for fracking the deep shale rocks. The transportation of water for fracking also requires a large number of truck trips. Transportation has resulted in causing road damage and polluting the air in the neighborhood. The sand and propants used for fracking is almost double the amount used in conventional coal industry. It has also been found that fracking can cause small earthquakes and vibrations since it is disturbing the natural rock layers under the earth. For gallons of water used in fracking the 2% of the chemicals used also turn out to be big figures. The chemicals used can be measured in hundreds of tons. This can prove to be very toxic for the soil and responsible for future health problems. The negative impacts of hydraulic fracking method are too many but again at the same time we cannot disregard the fact that it collects natural gas in many economical ways to ensure a clean supply of fuel.
The process of Fracking is exempt from the Safe water Drinking Act (Energy Policy Act of 2005)and hence the companies do not disclose the chemicals being used. Regulators are unaware of them as well since this process does not come under the act. However, there has been a repeal for this bill in the year 2011 in the US Congress. The water that is pumped into the ground is claimed by the companies that it does not enter the water aquifers but this has not been the case in several instances. As the water is pumped with numerous chemicals, some it can find its way back up and contaminate ground water as these are loaded with volatile organic chemicals. Though Diesel fuel is not supposed to be used as part of the fracking liquid, it has been found by the long study conducted by the government that many companies have violated this rule.
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