The formation of acid rain and how acid rain is formed

Modern industry, agriculture and transportation emit more pollutants (including acids and alkalis) and rise to the ground with dust, disperse, migrate, transform and then settle to the ground by gravity, or are washed by rain and snow to reach the ground. Acids can destroy vegetation, acidify soils, acidify waters, cause aquatic and terrestrial ecological imbalances, accelerate rock weathering and metal corrosion.

Acid rain is formed by the emission of certain substances into the atmosphere by natural and human activities; Some of the substances are neutral, such as sea salt, NaCl, KCL, etc., which are blown into the air by the wind and waves; Some substances are acidic, such as SOX and NOx, acidic dust (volcanic ash), etc.; Some are alkaline, such as NH3 and particles raised by windswept deserts and alkaline soils; Some are not acid-alkaline, but can play a catalytic role in the migration and transformation of acid-base substances, such as CO and ozone; The pH of precipitation is the result of their interaction and neutralization with each other during the rain washout process. The pattern of emissions from natural and human activities is completely different: over a longer period of time, such as a century or even centuries, the former's emissions remain roughly unchanged; The latter, on the other hand, has increased significantly within decades or even decades in some areas where the economy is taking off.

The sulphur dioxide in the exhaust gas emitted from the plant is mixed with rainwater to produce acid rain. As the name suggests, acid rain is strongly corrosive, can damage the surface of buildings, human beings and clothing, and can also cause water pollution and mass death of aquatic plants when it falls into the water. Most of them occur in areas with developed economies, especially heavy industry.

The rain of ph is called acid rain.

The main reason is too much nitrogen oxides, sulfur oxides.

Humans emit large amounts of acidic gases.

Acid rain is mainly caused by the anthropogenic release of large amounts of acidic substances into the atmosphere. Acid rain in China is mainly caused by the burning of large quantities of coal with high sulfur content, mostly sulfuric acid rain and less nitric acid rain. In addition, the exhaust fumes emitted by various motor vehicles are also an important cause of acid rain.

Acid rain refers to rain, snow, or other forms of precipitation with a pH less than that. During the formation and fall of rain and snow, sulfur dioxide, nitrogen oxides and other substances in the air are absorbed and dissolved, forming acidic precipitation with a pH lower than that. Acid rain is mainly caused by the anthropogenic release of large amounts of acidic substances into the atmosphere.

Acid rain in China is mainly caused by the burning of a large amount of coal with high sulfur content, mostly sulfuric acid rain, less nitric acid rain, in addition, the exhaust gas emitted by various motor vehicles is also an important cause of acid rain. Some areas of China have become areas prone to acid rain, and the scope and extent of acid rain pollution have attracted close attention.

Acid rain samples collected in a certain place cannot be regarded as acid rain areas, because there can be dozens of rains in a year, and a certain rain may be acid rain, and a certain rain may not be acid rain, so it depends on the annual average.

At present, the scientific criteria for defining acid rain areas in China are still under discussion, but it is generally believed that the average annual precipitation pH is higher than that and the acid rain rate is 0-20%, which is a non-acid rain area; The pH is between 10-40%, which is a light acid rain area.

pH between, the acid rain rate is 30-60%, which is a moderate acid rain area; The pH is between 50-80%, which is a heavier acid rain area. The pH is less than that, and the acid rain rate is 70-100%, which is a heavy acid rain area. This is known as the five-level standard.

In fact, Beijing, Lhasa, Xining, Lanzhou and Urumqi have also collected several acid rain showers, but the average annual pH and acid rain rate are within the standard of non-acid rain areas, so they are non-acid rain areas.

Acid rain is acidic precipitation with a pH lower than that absorbs and dissolves sulfur dioxide, nitrogen oxides and other substances in the air during the formation and fall of rain and snow. Acid rain is mainly caused by the anthropogenic release of large amounts of acidic substances into the atmosphere. The main causes of acid rain in China are the massive burning of coal with high sulphur content and the massive emissions from motor vehicle exhaust.

Acid rain can lead to soil acidification. The soil contains a large amount of aluminum hydroxides, and after soil acidification, it can accelerate the weathering of aluminum-containing primary and secondary minerals in the soil and release a large number of aluminum ions, forming a form of aluminum compounds that can be absorbed by plants. Plants absorb aluminum for a long time and excessively, can be poisoned and even die.

The five-level standard for acid rain.

The average annual precipitation pH is higher, and the acid rain rate is 0-20%, which is a non-acid rain area. The pH is between 10-40%, which is a light acid rain area. pH between, the acid rain rate is 30-60%, which is a moderate acid rain area; The pH is between 50-80%, which is a heavier acid rain area. The pH is less than that, and the acid rain rate is 70-100%, which is a heavy acid rain area.

There are various methods to control acid rain, such as developing new energy sources, reducing sulfur dioxide emissions, re-emitting gases from industrial production after treatment, and low-carbon travel. But this requires the participation of the whole people, starting with me.

The main measures to reduce sulphur dioxide emissions in the world are:

1.Raw coal desulfurization technology can remove about 40% to 60% of inorganic sulfur in coal.

2.Priority is given to low-sulphur fuels, such as low-sulphur coal and natural gas, which contain less sulphur.

3.Improve coal-fired technologies to reduce sulphur dioxide and nitrogen oxide emissions from coal combustion. For example, liquefied coal-fired technology is one of the new technologies that has been welcomed by various countries.

It is mainly used to add limestone and dolomite, react with sulfur dioxide, and generate calcium sulfate to be discharged with ash.

4.The flue gas formed after coal combustion is desulfurized before it is discharged into the atmosphere. The lime method is mainly used to remove 85%-90% of the sulfur dioxide gas in the flue gas.

However, although the desulfurization effect is good, it is very expensive. For example, the cost of installing a flue gas desulphurisation unit in a thermal power plant can be as much as 25% of the total investment in the plant. This is also one of the main difficulties in managing acid rain.

5.Develop new energy sources such as solar, wind, nuclear, combustible ice, etc.

Sulfur dioxide and nitrogen oxides from burning fossil fuels (coal, oil, natural gas) and environmental pollution are the main causes of acid rain formation. Since the beginning of the industrial age, the exploitation and exploitation of coal and oil has seriously polluted the air, when a large number of chemicals and pollutants enter the atmosphere. These pollutants eventually mix with water to form acid rain.

Natural disasters can also lead to the formation of acid rain, such as volcanic eruptions or forest fires. Volcanic eruptions emit large amounts of sulfur dioxide gas, which generally lead to the formation of acid rain after volcanic eruptions, and forest fires also emit a certain amount of sulfide.

Hazards of acid rain.

1. Acid rain can lead to soil acidification. The soil in southern China was originally mostly acidic, and then washed by acid rain, which accelerated the acidification process. The soil in northern China is alkaline, has a strong buffer capacity for acid rain, and cannot be acidified for a while and a half.

2. Acid rain can dissolve the hardened cement on the surface of non-metallic building materials (concrete, mortar and lime sand bricks), resulting in cavities and cracks, resulting in reduced strength and damage to buildings. Building materials become dirty and black, affecting the quality of the city's appearance and urban landscape, which is known as the "black shell" effect.

Acid rain is mainly caused by man-made emissions of large amounts of acidic substances into the atmosphere, followed by some natural emissions.

Due to the destruction of the natural world by human beings, more and more natural disasters occur, acid rain is one of them, in order to let everyone have the awareness of protecting the environment, I will tell you how acid rain is formed!

01 Artificial Emissions:

With the improvement of living standards, almost every household has driven a car, and the car is run by burning gasoline, we know that gasoline contains sulfur components, once burned, a large amount of sulfur dioxide will be produced, when they are released into the air, it will destroy the ozone layer, leading to the formation of acid rain, in addition, the combustion of fossil fuels such as coal, oil and natural gas will also release sulfur dioxide, the high temperature in the coal combustion process makes the nitrogen and oxygen in the air synthesize into nitric oxide, and then converted into nitrogen dioxide, Causes acid rain.

02 Natural Emissions:

In addition to the harmful substances that our human activities will produce to cause acid rain, nature will also produce some bad substances, such as fog foam in the ocean, which will carry some sulfuric acid into the air; After the death of organisms, some sulfides can be decomposed by bacteria, which can then be converted into sulfur dioxide; Volcanic eruptions also bring out a lot of sulfur dioxide gas; Lightning also partially combines nitrogen and oxygen in the air to form nitric oxide, which is then oxidized to nitrogen dioxide in the troposphere.

03 A large amount of sulfur dioxide emitted in daily life undergoes the "rain formation process in the clouds", and the liquid phase oxidation reaction occurs, forming sulfuric acid raindrops and nitric acid raindrops; After the "cloud erosion process", large raindrops are formed, and finally land on the ground, forming acid rain. Due to the large amount of coal burning in China, the acid rain in China is sulfuric acid rain. And the countries that burn a lot of oil rain nitric acid.

04 Acid rain in China is mainly sulfuric acid type, and the three major acid rain areas in China are:

1.Southwest Acid Rain Area: It is a serious precipitation pollution area second only to the acid rain area in Central China.

2.Central China Acid Rain Area: It has become the acid rain pollution area with the largest range of acid rain pollution and the highest central intensity in China.

3.Acid rain area along the east coast: Its pollution intensity is lower than that of central and southwest China.

The three major acid rain regions in the world are: Western Europe, North America, and Southeast Asia.