China’s war on pollution targets steel mill slag heaps

China Materials 10 December 2018 17:20 (UTC +04:00)
China’s self-styled war on pollution is extending to a new front: the solid waste that makes up thousands of slag heaps around the country, a by-product of its record steel output
China’s war on pollution targets steel mill slag heaps

China’s self-styled war on pollution is extending to a new front: the solid waste that makes up thousands of slag heaps around the country, a by-product of its record steel output, Trend reports referring to The South China Morning Post.

Beijing has been fighting to clean up the nation after years of breakneck economic growth took their toll on the environment, with its massive steel sector bearing the brunt of its vigorous campaign.

Hundreds of steel mills have been shut over the last few years for failing to comply with tougher environmental rules, with others forced to install better equipment to curb emissions and use higher-quality raw materials such as iron ore and coking coal.

But now industrial debris like slag is increasingly coming under the spotlight as well, potentially pressing steelmakers to tackle the pilings problems head on at a time when they are grappling with weaker profit margins.

“We will spare no effort in addressing solid waste-related environmental issues by strengthening inspections and improving disposal capabilities for dangerous waste,” the Ministry of Ecology and Environment said in response to questions about the push against such pollution.

The world’s top crude steel producer, which last year made a record 831.7 million tonnes of the material, churns out over 100 million tonnes of steel slag annually.

However, the industry recycles less than a third of that waste into products such as cement or concrete, leaving the rest stacked in heaps or dumped illegally.

That compared to slag utilisation rates of around 98 per cent in Japan and 87 per cent in Europe, the University of Science and Technology Beijing said in a study published in June.

“This dumped slag has damaged farmland and added pollution to the water and air,” the USTB study said.

Underscoring the government’s ramped up drive against steel waste, it this year began imposing a blanket 25 yuan (US$3.64) levy for every tonne of solid waste generated by industrial companies – that runs to 12.5 million yuan (US$1.82 million) for a mill that produces 500,000 tonnes of slag a year.

China has also intensified its “name-and-shame” tactics, saying in June that the country’s third biggest steelmaker, Jiangsu Shagang Group, had dumped millions of tonnes of untreated waste, including slag, in landfills near the banks of the Yangtze River, contaminating nearby soil and water.

In response, the steelmaker pledged to build a 2 billion yuan slag treatment plant.

“Our company has published our improvement plan,” an official at the office of Shagang’s board of directors said last week.

Last month, the environment ministry accused mid-sized steelmaker Gaoyi Iron and Steel of illegally dumping large amounts of steel slag over a decade. A person who answered the phone at Gaoyi Steel said the company was working to rectify the issue, but declined to give details.

The environment ministry also said it would urge local governments to deal with solid waste issues, undertaking a special campaign to crack down on violations. It did not give further details.

Some producers have already taken steps to fight the problem.

Major steelmaker Anshan Iron and Steel Group (Ansteel) had invested around 1 billion yuan in eight slag processing lines with a total capacity of 11 million tonnes, Zhang Hewu, general manager at company unit Ansteel Green Resources Technology, said.

He said those facilities turned most waste into products such as cement and road construction materials, leaving only about 10 per cent to be stored.

The recycled products were mainly sold in China, with some going to Singapore, Qatar, South Korea and the United States, Zhang said at the firm’s headquarters in the city of Anshan in northeastern China.

Unlike Ansteel, many Chinese mills do not have slag recycling plants, which global firm Harsco Metals & Minerals says is boosting its business processing and recycling slag.

“Job opportunities [for the firm] have risen significantly since the beginning of this year,” said Zhang Yan, China head at Harsco Metals & Minerals, part of diversified firm Harsco Corp.

Harsco handled slag for state-owned mills with total steel production capacity of nearly 40 million tonnes, including a new contract for an 8.5 million-tonne mill, Zhang said, adding that the firm was also getting inquiries from private steelmakers.

But Zhang said there was a lack of financial incentive, for companies to recycle slag, particularly in less developed parts of the country.

A person close to the solid waste department at the environment ministry said targeting such waste was also more difficult than tackling direct air or water pollution, where devices could be used to monitor emissions.

“For solid waste, you can’t send inspectors to monitor a company for 24 hours and see if they dump their trash illegally,” he said.