CAUSES OF AIR POLLUTION IN CHINA
Coal plant in Linfen
Coal is the number once source of air pollution in China. China gets 80 percent of electricity and 70 percent its total energy from coal. Factories and homes run on power from plants that overwhelmingly use coal; and in the winter, many heating boilers in the north also burn coal. Before much of the coal burn was high-polluting high-sulfur coal. Less of this used than before and more coal plants have scrubbers and other anti-pollution devises. Around six million tons of coal is burned everyday to power factories, heat homes and cook meals.
More cars and trucks crowd the roads. Expanding cities consume cement, steel and chemicals, the production of which add pollutants to the air. Expanding car ownership, heavy traffic and low-grade gasoline have made cars a leading contributor to the air pollution problem in Chinese cities. In Wuhan in Hubei Province old tires and asphalt are used as fuel to fire pottery kilns, creating some nasty pollution in the process. In February 2013 Deutsche Bank said that China’s current economic policies would result in an enormous surge in coal consumption and automobile sales over the next decade. “China’s air pollution will become a lot worse from the already unbearable level,” analysts at the bank ssaid, calling for drastic policy changes and “a strong government will to overcome the opposition from interest groups.” The report estimated that the number of passenger cars in China was on track to hit 400 million by 2030, up from 90 million in 2012. [Source: Edward Wong, New York Times, March 21, 2013]
Some have suggested Beijing’s switching winter heating sources from coal to natural gas made smoh worse. Beijing undertook a massive and costly campaign to use cleaner energy. Natural gas is cleaner than coal, producing water and carbon dioxide when burnt, instead of the dust and smoke that coal produces. But the water vapour that burning natural gas produces can also increase the concentration of air pollutants near ground. Ongoing research has suggested that tiny water molecules in the air may speed up chemical reactions, leading to worse smog. Wang Zifa, a researcher with the Chinese Academy of Sciences’ Institute of Atmospheric Physics, said the burning of natural gas in China pumped more than 300 million tonnes of water into the atmosphere each year — equivalent to 30 times the amount of water in Hangzhou’s famous West Lake. Nevertheless, water vapour accounts for only a small, “almost negligible” fraction of water in the whole atmosphere, Wang said. “The use of natural gas hence was not a big contributor to the high humidity of Beijing’s smog, he said. [Source: South China Morning Post, 21 December, 2016]
Coal and Air Pollution in China
The burning of coal is the biggest factor contributing to northern China’s smog according to Professor Chai Fahe, a researcher with the Chinese Research Academy of Environmental Sciences. Emissions from burning coal in Beijing, Tianjin and Hebei — the most developed regions in northern China — were five times the national average. The situation worsens in winter when many urban and rural families in those regions also relied on coal for heating, he said. [Source: South China Morning Post, 21 December, 2016]
The production of coal-fired plants has slowed to some degree. They are no longer being produced at the rate of one a week. By the early 2010s they added 80 gigawatts of power a year, down from 100 gigawatts a few years in the mid 2000s. It was estimated that the use of cheap coal cost China $248 billion, the equivalent of 7.1 percent of GDP, in 2007 through environmental damage, strains on the health care system and manipulation of commodity prices. The figure was arrived at by the Energy Foundation and the WWF by taking into consideration things like lost income from those sickened by coal pollution. Coal has been tied to a number of health problems. In towns like Gaojiagao in Shanxi it has been linked with a high number of birth defects such neural tube defects, additional fingers and toes, cleft pallets and congenital heart disease and mental retardation.
Many places still burn large amounts of coal for heating. Coal produces thick, smoggy smoke. High sulfur coal is particularly nasty. It produces a rotten egg smell. Vaclav Smil, a Canadian expert on the Chinese environment from the University of Manitoba, told the New York Times, the Chinese “have this coal; they have to use it....Much of the coal is now coming from these very small coal mines, but there is no sorting, no cleaning or washing and this kind of coal generates a tremendous amount of pollution."
Low-Grade Coal Used for Heating: A Major Pollutant in China
Around 200 million residents in rural China, mostly in the northern parts of the country, use coal for household heating during the winter. To save money, many of them tend to use inferior types, according to the Economic Daily. The Chinese Daily reported: An inspection by the Ministry of Environmental Protection of 22 cities in northern China in 2015, officials came to the conclusion that coal burning — especially the low-quality coal — is the main cause of the steep deterioration in air quality over the winter months. [Source: Zheng Jinran and Wang Yanfei, China Daily, December 12, 2015]
“Coal burning for heating is a widespread phenomenon in the vast rural areas surrounding the few large modernized cities that have made the shift to cleaner energy. The inspectors found that 22 percent of the coal samples from Beijing failed to meet national standards, along with 27 percent from Tianjin and 38 percent from Hebei province, which has a much larger rural population.
“In many cities in Henan province, the coal used in rural areas was not covered by the local environmental authorities' regular monitoring system, the inspectors said. In fact, the management of coal usage in rural China has been loose, they said. Related government agencies, such as those in charge of housing and rural development, were also criticized for having failed to be environmentally responsible. As winter came around and many rural households started to use coal stoves for heating, it took only days for smog to build up in the skies of the region.
“Rural residential heating makes up only 2.6 percent of China's coal use, according to the National Bureau of Statistics. "But its impact on smog can't be ignored," said He Zhicheng, chief economist at Agricultural Bank of China. National environmental watchdog's data show that in November 2015 the reading of the major hazardous airborne pollutant PM2.5 saw an increase of close to 60 percent from 2014 in the Beijing-Tianjin-Hebei area, one of the three largest city-clusters on the Chinese mainland. There were four more smoggy days in Beijing in November 2015 compared with November 2014.
Coal and Acid Rain in China
Sulfur dioxide and nitrogen oxides are the main pollutants that cause acid rain, which is usually caused when sulfur emitted from coal-fired power stations and commercial installations mixes with oxygen. Nitrogen-oxide-derived acid rain is produced when nitrogen emitted from vehicles and power stations and other sources combines with oxygen. Acid rain has at least one positive point. It reduces the amount of methane.
China is the world’s top producer of airborne sulfur dioxide and particulate matter from coal combustion. Chinese factories and power plants spewed out 25.5 million tons of sulfur dioxide, the chemical that causes acid ran, in 2005, up 27 percent from 2000. By contrast the United States produced about 11 million tons. Levels of sulfur dioxide emissions in China in the mid 2000s were double what was regarded safe. Coal-burring power stations and coking plants are the main sulfur dioxide producers.
One survey in the 2000s found that a third of mainland China was regularly soaked in acid rain and half of the cities and counties surveyed receivde at least some acid rain. In some places every rainy day is an acid rain day and limestone buildings are dissolving in the acid air. The Guangdong-Guangxi-Guizhou-Sichuan basin south of the Yangtze is the largest single area in the world affected by acid rain pollution. A study in the early 2000s found that one third of crops in the Chongqing area had been damaged by acid rain. China sends some its acid rain abroad.
Underground Coal Fires in China
A coal fire Underground coal fires in China at one time were consuming 20 to 30 million tons of coal a year, pumping tons of ash, carbon dioxide, methane, carbon monoxide and sulfur compounds into the atmosphere. Some of the fires have been burning for centuries. By one count there are 56 underground coals fire currently burning in China. Coal fires produce huge amounts of harmful carbon dioxide and sulfur dioxide. The fires produce as much carbon monoxide each year as all the cars in the United States.
The underground coal fires are revealed by fumes and smoke that pour from cracks in the earth. The Wude coal field in Inner Mongolia, one of China’s largest coal fields, is the home of China’s largest coal fire and some argue one of the world’s worst environmental disasters. Sixteen of China’s coal fires burn here, spewing out acrid clouds of sulfur dioxide. The fires at the Wude field are at a depth of between 110 to 220 feet. They advance about 100 feet a year. An official in charge of putting the fires at Wude told Smithsonian magazine: “An underground coal fire is like a dragon. We can sense the dragon’s tail, that is, the area already burned. But satellite images show that the hottest, densest parts are far below the surface, or the dragon’s head. We can predict the path, and prepare to chop off its head.” Workers try to extinguish the fires by starving them of oxygen by burying them under a 3-foot-layer of dirt. Pouring water on them produces dangerous methane gas, so workers pour a water-clay slurry into cracks instead of water if a dousing strategy is employed. Even when the fires are extinguished the ground can take years to cool down.
In the early 2000s only 10 percent of China’s coal underground fires were being fought. They posed little immediate threat other than polluting the air in fairly remote places and cutting off access to some coal supplies. There have been some successes. In 2003, a centuries-old fire was extinguished near Urumqi after a four year battle. In 2009, a number of coal fires, one of which had been burning for 60 years, were put out in Xinjiang. The fires, which has been caused illegal mining and spontaneous combustion, had spread to more than 900,000 square meters and consumed 10 million tons of coal a year. The fires were put out through a coordinated plan of drilling, water injection and using earth to cut off oxygen.
Cement Plants and Pollution in China
Cement plants are among the biggest air pollution producers in China. They produce lots of dust in various sizes. They also need a lot of energy — heat of more than 2,600 degrees F from 400 pounds of coal for each ton of cement — to convert the limestone and other materials into the intermediate form of cement called “clinker.” Production generates huge amounts of heat that is released into the air.
To reduce coal transportation costs cement plants are often built in places that have a supply of coal nearby. Mining, coal processing and cement making produce high levels of pollution. Areas with cement plants can often be determined from many kilometers away by the grayish color of the air and the layers of dust on trees and the road.
Advanced cement plants recycle heat normally released into the air and use it to run turbines that generate electric power. The power then can be used to run the plants. These plants require 60 percent less energy, enough to cover the millions of dollars needed to build the advance plant, which take about in four years to construct. The technology for these system is supplied by the Chinese firm Dalian East Energy Development, which exports the technoloy to countries such as Vietnam, the Philippines and Pakistan and plans to use similar technology on steel plants in the future.
Ozone, Chinese Air Pollution and Global Warming
China produced 11,540 metric tons of CFCs in 1986 compared to 311,021 metric tons by the United States. In 2007 China produced 13,060 tons of CFCs compared to 1,088 by the United States. In 1980, China had only 32,000 refrigerators. By 1990 that figure jumped to four million. Chlorofluorocarbons (CFC's) leaking from refrigerators and air-conditioners are a major source of ozone-depleting gases. China now has a huge refrigerator industry, producing chlorofluorocarbons.
In 1987 China was reluctant to sign the Montreal Protocol, an international agreement to save the earth's ozone layer, because it believed it couldn't afford the research costs to come up with new ozone-friendly coolants. When the United States announced it would share the costs, China signed the protocol. The use of ozone-layer-depleting chemicals in India and China and to a less extent in Indonesia threatens to cancel out progress made in reducing the use of these chemicals in the developed world.
In western Tibet-Qinghai there is a mysterious "ozone valley" that thus far scientists have been unable to explain.
Charles W. Petit wrote in U.S. News and World Report, “In southeastern China, where haze has cut sunlight by 2 percent to 3 percent every 10 years since the 1950s, temperatures are dropping, while rising elsewhere in the country, presumably because of greenhouse gases. The changed temperature patterns have rerouted storm tracks, one recent Chinese study said. The study blamed the shift for severe floods in the nation's south in recent years, coupled with drought in the north. It ranked the new weather pattern as the greatest sustained change in China's climate in more than 1,000 years. [Source: Charles W. Petit, U.S. News and World Report, March 17, 2003 :|:]
“Some scientists also suspect that the pollution cloud could be cooling the sea surface and slowing evaporation in the far western Pacific, off Asia. The effects could ripple across half the globe to the United States, because the western Pacific is the breeding ground for El Niños, the bouts of Pacific warming that change rainfall across the Americas and beyond. All of this is enough to make Asia's brown cloud, and the sparser hazes elsewhere, into a global climate threat. Fortunately, hazes are far easier to counter than greenhouse gases like carbon dioxide. Clean up industry and smother the fires, and in a few weeks rain would wash the skies clean. Carbon dioxide, in contrast, lingers for centuries, and ordinary pollution controls can't touch it. :|:
Image Sources: 1) University of Washington; 2) Impact Lab; 3,5 ) Natalie Behring, Bloomberg, Environmental News.; 4) University of Utah; 6) Environmental News; 7) David Wolman Blogspot; 8) NASA; 9) Julie Chao http://juliechao.com/pix-china.html ; You Tube
Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, National Geographic, The New Yorker, Time, Newsweek, Reuters, AP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.
Last updated June 2022