Monday, May 19, 2014

China's pollution concerns experts around the world

HEXIGTEN QI, China — The new coal plant here is an industrial fortress of boilers, tanks and towers that stretches across a lonely plateau in Inner Mongolia. 

Day and night, it vents huge gray clouds of steam and emits an awful stench. 

Though it might seem odd, this is part of China’s campaign to combat the nation’s notorious urban smog. The plant transforms low-grade coal into a cleaner-burning methane gas that can be piped to cities, replacing dirtier fuels that now are used to cook meals, heat homes and produce electricity. 

The Chinese leadership has called for the accelerated development of these coal-to-gas plants, and more are under construction. 

But embracing this technology to fight air pollution involves a serious environmental trade-off. The plants that produce this gas spew far more carbon than those that burn coal to generate electricity.

A study published last year in the journal Energy Policy found that producing, transporting and combusting this coal-generated gas results in up to 82 percent more carbon emissions than burning China’s coal directly to generate electricity.

If all the plants with initial government approval are built, they could boost the nation’s annual carbon emissions by more than 7 percent over 2012 levels, according to an analysis by a co-author of that study.

“They’re going to lock in emissions. China — and the world — will bear the consequences for decades,” said Robert Jackson, professor of environment and energy at Stanford University.

Such large-scale development would be a significant blow to global efforts to curb CO2 emissions, which already are changing the planet’s climate and causing the oceans to become more acidic.

The gas plants are part of a broader expansion of the Chinese coal industry in Inner Mongolia and other provinces in the north and west.

That development includes large electrical power plants, as well as refineries that turn coal into chemicals. These plants could help keep China’s total coal consumption steady — or edging higher — even as the government cracks down on coal use in 12 populous provinces and dramatically expands reliance on zero-carbon fuels such as nuclear, hydroelectric, wind and solar.

Chinese officials acknowledge that carbon emissions are a serious long-term threat to the nation. Rising sea levels later in the century would threaten coastal cities, and water shortages would intensify, according to a government report.

But dirty air is the front-burner environmental issue in China.

Air pollution is cutting an average of more than five years from the life expectancy of about 500 million people in northern China, according to an analysis published last year in the Proceedings of the U.S. National Academy of Sciences.

In Beijing, people are so edgy that even on clear, blue-sky days, many residents don face masks to protect against soot particles.

“We will declare war against pollution and fight it with the same determination we battled poverty,” Li Keqiang, China’s prime minister, announced in a speech this year.

Much of the urban smog comes from using coal to cook, heat homes, generate electricity and power industry. By contrast, methane — the prime component of natural gas — burns much cleaner than coal, helping to reduce smog and improve indoor air quality fouled by coal-fired stoves.

But China’s petroleum companies can’t meet the demand for methane from traditional gas fields, and they lag far behind their U.S. counterparts in developing new reserves through fracking.

While China buys increasing amounts of gas from other nations, the government is wary of becoming too dependent on imports.

So China’s leaders have embraced coal-to-gas plants as part of the nation’s energy future.

In September, facing a growing public outcry about smog, China’s State Council announced that development of the coal-to-gas industry would be sped up over the next decade. At least 18 plants have obtained initial approval from Chinese officials for construction, according to the World Resources Institute.

Developers are seeking to build several dozen additional plants.

It is uncertain how many will happen, given the growing concerns about the massive carbon load and water demands that would result from so many new plants.

Turning coal into a more refined methane gas is a complicated process, and there have been some early stumbles in the development of this technology.

To produce the methane at the Hexigten Qi plant, the coal is fed into large pressurized vessels where it is combined with steam. The resulting gas is sent through a series of purifying columns.

The Hexigten Qi plant is operated by Datang International, a state-owned power company that is investing more than $4 billion to bring it into full production. Datang’s plant is one of two such facilities that opened in the past year.

The first phase of the plant began operating in December. It quickly shut down in January and did not start up again until this spring because of corrosion problems, according to Chinese news reports.

At full capacity, the plant is supposed to produce 4 billion cubic meters of natural gas annually, according to Datang documents. That’s equal to more than 40 percent of all the natural gas consumed in Beijing in 2012.

During the past decade, energy development has turned Inner Mongolia into China’s largest coal-producing region, bringing new prosperity and stirring tension.

Some ethnic Mongolians have been pushed off grazing lands as mines, roads and industrial plants take up grasslands where herds once roamed.

Mongolians are now a minority in a region of 24 million people dominated by the Chinese Han. Yet their heritage still defines the region, hearkening back to an era when their armies conquered much of Asia

Among Mongolians, there is plenty of mistrust of the government and the coal boom it has encouraged.

Three years ago, a 35-year-old Mongolian herder named Mergen was killed by a coal truck as he joined with others to protest the impact of mining on their lands outside Xilinhot.

His death prompted thousands of herders, students and other ethnic Mongolians across the region to take to the streets in rare demonstrations. They evolved from anger about Mergen’s death to broader frustrations with the toll of mining on traditional lands.

The protests “really got huge,” said a man who was a high-school classmate of the trucker’s. “ The protesters were so furious that they tried to drive to Beijing carrying the dead man’s body. But the government blocked the road.”

The trucker was eventually executed, as the government sought to calm the unrest.

In the months ahead, Datang’s troubled startup will be monitored by Chinese government officials eager to learn more about the technology and economics of turning coal into gas.

China’s environmentalists hope the government will back away from embracing an industry that emits so much carbon.

The coal industry, however, is eager for new markets. Last year, the Datang plant began buying coal from a mine that was struggling with its first downturn in sales in a decade.

Despite pollution, carbon emissions and climate change, Cheng Xiaoliang, the mine’s vice general engineer, is confident about the future.

“I firmly believe that coal is going be the main generating source of energy at least for the next 50 years,” he said. “No matter what, China still needs coal.”

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