TIANJIN -- Tianjin Municipality in north China increased the pollution fee imposed for smoke and dust discharged by industrial enterprises by nine times on May 1, in a push to reduce emissions.

Under the adjustment, the fee is 2.75 yuan ($0.45) per kg of smoke and dust, compared with 0.275 yuan per kg under the previous rate, which has been used since 2003. Dust and smoke are important components of PM2.5 and PM10, which are key air pollutants.

The fee for dust at construction sites was increased 10 times to 1.5 yuan per kg, according to a joint document issued by the Tianjin economic planning, finance and environmental protection departments.

"The 10 times increase of the fees for dust emissions is intended to urge enterprises to actively take measures to control pollutants to improve air quality," said Li Jun, an official with the Tianjin Municipal Reform and Development Commission.

Chinese authorities have increased the fines for polluters in order to force them to abide by law and pay more attention to environmental protection.

In January, the country's amended Environmental Protection Law came into effect, bringing with it tougher measures against polluters and lifted the cap on pollution fines.

A sewage purification research center received a record fine of 6.74 million yuan for discharging four to five times the national standard of such pollutants as the chemical oxygen demand in Zhangjiakou City, Hebei Province in late March. It is the heftiest pollution fine for enterprises in the city, said a local environmental official early this month.

Beijing's environmental watchdog announced late April it had imposed the capital's largest fine of 3.9 million yuan on a joint venture food company over water pollution.

A guideline unveiled by the central authorities in early May said China aims for "major progress" in building a resource-saving and environment friendly society by 2020, with carbon dioxide emissions down 40 to 45 percent from the 2005 level.

China will strive to reduce 15 million tonnes of outdated steel production capacity this year, according to the top economic planner.

Hebei has closed nearly 10,000 factories over the past two years to reduce its excessive steel, glass and concrete production capacities and pollution, said Zhou Benshun, Communist Party chief of the province.

Tianjin has joined hands with neighbors Beijing and Hebei to treat and control air pollution over the past two years. The region covering Beijing, Tianjin and Hebei is one of the heavily polluted areas in China.

After the closure of three coal-burning thermoelectric plants, Tianjin plans to shut 180 coal boilers by October, realizing a reduction of 5 million tonnes in coal use this year.

The pressure to reduce pollutants and energy consumption also pushes industrial companies to upgrade technologies for recycling use of treated waste.

Jiangsu Oji Paper Co., Ltd, a Japanese plant in the eastern developed Jiangsu Province, has realized zero discharge waste water after adopting a film filtering technology developed by Chinese researchers.

The technology succeeded in turning 32,000-tonnes of waste water into clean water, industrial salt and dried mud each day. The company buys back 12,000 tonnes of the reclaimed water every day for production.

"As a major power in resource consumption and emission, China still faces tough tasks of energy conservation and emission reduction," said Sun Zhenqing, a researcher in environment and green development at Tianjin University of Science and Technology.