අම්ල වැසි

විකිපීඩියා, නිදහස් විශ්වකෝෂය වෙතින්
වෙත පනින්න: සංචලනය, සොයන්න
Processes involved in acid deposition (note that only SO2 and NOx play a significant role in acid rain).

අම්ල වැස්ස is a වැස්ස or any other form of අවක්‍ෂේපනය that is unusually ආම්ලික, i.e. elevated levels of හයිඩ්රජන් අයන (low pH). It can have harmful effects on ශාක, ජලජ ජීවීන්, හා infrastructure through the process of wet deposition. Acid rain is caused by emissions of compounds of ammonium, කාබන්, නයිට්රජන්, and සල්පර් which react with the water molecules in the atmosphere to produce acids. Governments have made efforts since the 1970s to reduce the production of sulfur dioxide into the atmosphere with positive results. However, it can also be caused naturally by the splitting of nitrogen compounds by the energy produced by lightning strikes, or the release of සල්පර් ඩයොක්සයිඩ් into the atmosphere by volcano eruptions.

නිර්වචනය[සංස්කරණය]

"අම්ල වැස්ස" යනු ෙතත්(වැසි, හිම, sleet, මීදුම, cloudwater, and dew) හා වියළි(acidifying particles සහ වායු) අාම්ලික සංරචක තැන්පත් වීම සදහා භාවිතා කරන යෙදුමකි.

ඉතිහාසය[සංස්කරණය]

Trees killed by acid rain

මානුෂ ක්‍රියාකාරකම්[සංස්කරණය]

අම්ල deposition[සංස්කරණය]

තෙත ( නිධිසාධනය )[සංස්කරණය]

Wet deposition of acids occurs when any form of precipitation (rain, snow, etc.) removes acids from the වායුගෝලය and delivers it to the Earth's surface. This can result from the deposition of acids produced in the raindrops (see aqueous phase chemistry above) or by the precipitation removing the acids either in clouds or below clouds. Wet removal of both gases and aerosols are both of වැදගත්කම for wet deposition.

වියළි deposition[සංස්කරණය]

Acid deposition also occurs via dry deposition in the absence of precipitation. This can be responsible for as much as 20 to 60% of total acid deposition.[1] This occurs when particles and gases stick to the ground, plants or other surfaces.

වළක්වා ගැනීමේ ක්‍රම[සංස්කරණය]

තාක්‍ෂණික විසදුම්[සංස්කරණය]

In the United States, many coal-burning power plants use Flue gas desulfurization (FGD) to remove sulfur-containing gases from their stack gases. An example of FGD is the wet scrubber which is commonly used in the U.S. and many other countries. A wet scrubber is basically a reaction tower equipped with a fan that extracts hot smoke stack gases from a power plant into the tower. Lime or limestone in slurry form is also injected into the tower to mix with the stack gases and combine with the sulfur dioxide present. The calcium carbonate of the limestone produces pH-neutral calcium sulfate that is physically removed from the scrubber. That is, the scrubber turns sulfur pollution into industrial sulfates.

In some areas the sulfates are sold to chemical companies as gypsum when the purity of calcium sulfate is high. In others, they are placed in landfill. However, the effects of acid rain can last for generations, as the effects of pH level change can stimulate the continued leaching of undesirable chemicals into otherwise pristine water sources, killing off vulnerable insect and fish species and blocking efforts to restore native life.

Automobile emissions control reduces emissions of nitrogen oxides from motor vehicles.

Emissions trading[සංස්කරණය]

In this regulatory scheme, every current polluting facility is given or may purchase on an open market an emissions allowance for each unit of a designated pollutant it emits. Operators can then install pollution control equipment, and sell portions of their emissions allowances they no longer need for their own operations, thereby recovering some of the capital cost of their investment in such equipment. The intention is to give operators economic incentives to install pollution controls.

The first emissions trading market was established in the United States by enactment of the Clean Air Act Amendments of 1990. The overall goal of the Acid Rain Program established by the Act[2] is to achieve significant environmental and public health benefits through reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx), the primary causes of acid rain. To achieve this goal at the lowest cost to society, the program employs both regulatory and market based approaches for controlling air pollution.

මේවාත් බලන්න[සංස්කරණය]

References[සංස්කරණය]

  1. UK National Air Quality Archive: Air Pollution Glossary
  2. Clean Air Act Amendments of 1990, 42 U.S. Code 7651

වැඩිදුර කියැවීම්[සංස්කරණය]

  • John McCormick, Acid Earth: The Global Threat of Acid Pollution (London: Earthscan, 1989) ISBN 978-1-85383-033-4
  • Likens, G. E., R. F. Wright, J. N. Galloway and T. J. Butler. 1979. Acid rain. Sci. Amer. 241(4):43-51.
  • Weathers, K. C. and G. E. Likens. 2006. Acid rain. pp. 1549–1561. In: W. N. Rom (ed.). Environmental and Occupational Medicine. Lippincott-Raven Publ., Philadelphia. Fourth Edition.

බාහිර සබැඳුම්[සංස්කරණය]

"http://si.wikipedia.org/w/index.php?title=අම්ල_වැසි&oldid=285809" වෙතින් සම්ප්‍රවේශනය කෙරිණි