Industry Highlights China's Growing Coal Ash Problem
/Oct 1st — If you know where to look and what to look for, zooming in on nearly any coal-fired power plant in China from a Google Earth satellite image will yield stark images of leftover residuals from coal combustion piling high in landfills near the facilities.
Up to 1.5 billion metric tons of coal ash—mostly from the bottom ash that falls down after coal is burned, or fly ashthat is captured in the stacks as the particulate matter rises with the heat and later scrubbed out—is stockpiled in China, making it the country's No. 1 industrial solid waste by volume.
“There is a very unique situation with coal ash in China, and unique solutions need to be customized to the problem,” said David Harris, chairman of the Asian Coal Ash Association.
Of the nearly 600 million metric tons generated annually in the country, 30 percent to 40 percent end up in landfills, while the rest is utilized as a component for cement, concrete and building materials such as bricks, fuel for the building boom continuing in the more prosperous eastern part of the country.
By comparison, the U.S. generated around 110 million metric tons of coal ash in 2012.
There are no comprehensive national regulations in China regarding the storage of coal ash that requires bottom lining of landfills to prevent potentially toxic heavy metals from leaching into nearby fields or into groundwater sources, nor are there requirements to cap or cover the ash to prevent blowing dust from getting into the atmosphere.
Some estimates in China show that around 20 percent of the small particulate matter (PM-2.5) in the atmosphere—the particles most damaging to the lungs—is from coal ash blown off of landfills, contributing to air pollution in major northern cities such as Beijing, Tianjin and Shanghai.
The U.S. has regulations to ensure the structural stability of coal ash landfills and to protect groundwater after a number of recent incidents of coal ash spills, including the 2014 Dan River spill from a Duke Energy Facility near Eden, N.C.
Satellite Images
At a coffee shop in the south China city of Shenzhen, where the Asian Coal Ash Association is based, Harris shows Bloomberg BNA satellite images of some of sites, highlighting a coastal area on the west side of Qinzhou Bay, where a facility supplying power to the Guangxi-Zhuang autonomous region sits.
Images seem to show that coal ash is spreading into nearby fields, and Harris said coal ash also is being dumped into the ocean for coastal reclamation for eventual development.
About 1,500 miles due north in Shuozhou, Shanxi province is the heart of the country's coal belt and a region often shrouded in severe air pollution. There, the local municipal government and coal power industry are attempting to change the image of the area and industry, which Greenpeace targeted in a 2010 campaign.
At the time, the environmental group released damaging images of issues at 14 coal power facilities in the area, including coal ash dust blowing off massive landfills.
New Uses
At an annual Asian Coal Ash Association conference from Sept. 22–24 in Shuozhou, Wang Anpang, party secretary of Shuozhou, said the municipality is promoting the utilization of coal ash.
It is establishing three industrial solid waste demonstration clusters with around 50 businesses to pilot techniques for using coal ash, which range from steamed bricks to processing ultrafine fly ash with higher mineral contents that can be used in a variety of industries.
Site Bloomberg BNA visited after the conference showed some of the companies using the ash for bricks and for a stucco material sprayed onto walls.
Ci Yuansheng, an expert on coal ash at the Institute of Technical Information for the Building Materials Industry of China, said about 44 percent of the coal ash being used goes toward making cement, with 28 percent for building materials and 16 percent for concrete.
“This coal ash waste brings a lot of possible environmental risk but also a potential resource,” said Chen Guanhu, vice director of the Shanxi Economic and Information Commission.
Chen said it was not a provincial policy to reduce coal ash waste and to promote its use, but the “low value added and low tech content,” as well as the “small market size” for the companies using the materials, mean that “it is not as widely used around China as it could be. We need more technological innovation to improve the use.”
‘Made in China.'
A national policy to modernize manufacturing called Made in China 2025 that the State Council launched in May could spur further utilization of coal ash, as recycling resources and industrial solid waste were mentioned in the documents, said Li Li, deputy director of the Energy Savings and Resource Center of the Ministry of Industry and Information Technology.
A regional disparity has been created regarding utilization of coal ash, conference speakers said.
While rates of use in the east are at least 80 percent, in the central parts of the country, rates of use range between 30 percent to 80 percent. And in the western region, where more coal-fired power facilities are going into operation in areas such as the Xinjiang-Uighur autonomous region, rates are often less than 30 percent.
Zhai Guanjie, director of the Coal Ash Research Institute at Dezhou University in the eastern province of Shandong, told Bloomberg BNA that in his province “most if not all of the coal ash is being utilized” and construction is the main driver.
Potential Markets
The prime environmental issue with coal ash in China at the moment is dust blown from poorly covered dumpsites.
“Coal ash in China is going to become a bigger issue than it is today,” said Boyd Ramsey, representing the AmericanCoal Ash Association at the conference.
He explained that part of the reason is an unintended consequence of China requiring stronger limits on airborne emissions from coal-fired power stacks. Those emissions controls can result in more fly ash building up in the stacks.
Ramsey's company, GSE Environmental Lining Technology Co. Ltd., has set up operations in Suzhou, near Shanghai, to provide dumpsite protections as they become needed.
Products like cement made of 95 percent fly ash, which is being brought to China by CeraTech Inc., also could help, said company Executive Vice President Mark Wasilko. CeraTech set up a test facility in Guangdong province that was able to reduce sulfur dioxide emissions from a coal power facility that needed to add calcium to the combustion process to enhance the fly ash.
To contact the reporter on this story: Michael Standaert in Shenzhen, China, at [email protected]
To contact the editor responsible for this story: Greg Henderson at [email protected]
