Tough battle ahead against smog

Burning coal and industrial emissions,exacerbated by burning crops, have covered northern Chinese cities in heavy smog, prompting experts to warn of the tough battle ahead as heating season starts.

Smog shrouded Beijing starting on Monday and did not disappear until dispersed by rain on Thursday. Environment authorities have issued repeated health warnings, advising people to stay indoors.

Neighboring Tianjin municipality and several cities in Hebei province have also been cloaked by smog this week.

Beijing environment statistics show the October-to-December quarter suffers the worst pollution, with smog once every four days on average. Experts say the main culprit is still pollutants discharged by heavy industry, though burning crop residue and lack of wind also contribute.

Hebei issued a broad ban on coal burning and industrial discharge from late August to early September to ensure air quality for the parade in Beijing to mark the 70th anniversary of the end of WWII.

Zhang Liang, an environment engineer in Hebei Provincial Environment Emergency and Heavy Pollution Warning Center, said pollution was cut by 60 percent during the period.

Air quality has improved in the Beijing-Tianjin-Hebei area compared to last year thanks to consistent effort by the government. In October last year, northern China was hit by four heavy pollution outbreaks, while the number was reduced to two this year.

However, experts said reducing smog is getting harder as Hebei still relies heavily on industry, including steel, chemical, construction material and glass industries.

In 2015, Hebei required 9.8 billion cubic meters of natural gas for its industrial plants, but was still 3.3 billion cubic meters short. The gap in demand will expand to 10.7 billion in 2017, statistics show.

Several city environment chiefs told Xinhua that money is needed to fund coal-to-electricity and coal-to-gas switches at local plants. In addition, technological support is also in heavy demand.

"We have invested heavily to contain sulphuric emissions from steel plants, but even after upgrading, the emissions can not be sufficiently controlled," said Chen Enhui, environment chief of Chengde city.

China uses four billion tons of coal every year, half of which are used by power plants and others by metallurgy, cement and industrial furnaces, said Lu Guangjie, an expert of China Association of Environmental Protection Industry (CAEPI).

"Most of the emissions by power plants have reached national emission standards, but it is difficult for other coal-burning facilities to reach such standards, and thus they should switch to gas," he said.