Through intense cross-sectoral cooperation, north China's Shanxi Province has further processed industrial pollutions by turning them into useful products and clean energy.
The Jinnan Steel Group in Shanxi's Linfen City needs to use 7,500 tons of coke and 19,000 tone of melted iron to produce 24,000 tons of steel every day. In this process, 2.76 million cubic meters of converter gas will be generated.
While for a local coking factory, it will produce more than 9,000 tons of coke every day, along with 3.78 million cubic meters of coke oven gas.
Since these waste gases cannot be emitted directly, then how to deal with them?
"Traditionally, we would heat up and burn the coke oven gas to generate electricity. This is highly energy-consuming with massive emissions. Now, we'll send the extra coke oven gas to chemical plant," said Shi Yunpeng, director of Jinnan Steel Group's Liheng coking factory.
In the chemical plant, these waste gases were changed into useful products, such as glycol and liquefied natural gas.
"After chemical process treatment such as compression, purification, separation and purification, coke oven gas and converter gas will turn into 300,000 tons of ethylene glycol and 150,000 tons of liquefied natural gas products per year. Such treatment will also reduce 1.36 million tons of carbon dioxide emissions from the upstream industry," said Han Tingjie, chief despatcher of production technology department with Shanxi Woneng Chemical Technology Co., Ltd.
The pollution can also become hydrogen, which will later replace coke to heat up blast furnaces for making iron.
"After hydrogen smelting, this blast furnace can cut coke by 40,000 tons per year. So three blast furnaces can reduce 120,000 tons of coke and 330,000 tons of carbon dioxide emissions every year," said Ding Chao, person in charge of Jinnan iron mill's No.3 blast furnace.
For now, Shanxi's steel and coking industries have said goodbye to high pollution and high energy consumption, heading towards an environment-friendly future.
Coal-rich Shanxi Province steps up environment-friendly low-carbon circular growth
Environmental simulation and digital replication are among the new technologies now employed to protect the Dunhuang Mogao Grottoes, a 1,600-year-old UNESCO World Heritage site located in the Gobi Desert in Dunhuang City, northwest China's Gansu Province.
Researchers for decades have tried to find ways to protect the cultural heritage site, home to a vast collection of Buddhist artworks carved into the cliffs, from damage caused by natural or human factors.
A multi-field coupling lab on murals and ancient ruins protection under the Dunhuang Academy, the first of its kind in China to be employed in cultural relics preservation, was put into use by the end of 2020.
Located in the city of Dunhuang, the lab covers an area of 16,000 square meters. It is able to simulate the four seasons and the erosion by wind, rain and snow that the earthen relics could experience in a natural environment. It can also simulate temperatures ranging from minus 30 to 60 degrees Celsius and relative humidity ranging from 10 to 90 percent.
"In the 'summer house', we can simulate the environment in the southern region which is hot and humid. We can also simulate a dry environment with a temperature of over 40 degrees Celsius. [The temperatures and lighting] have impacts on the heritage sites," said Liu Xiaoying, a research fellow at the Multi-field Coupling Environmental Lab of Immovable Heritage under the academy.
Researchers at the lab not only study the local soil, but have also brought samples from heritage sites in other areas such as the northwestern city of Xi'an and Sichuan Province in southwest China to the lab.
The academy has been working with academic institutions including the University of Oxford and China's Northwest University in an international synchronous field trial.
With a controlled environment to its merit, the lab will play an important role in cultural heritage protection across the country, according to the academy.
"The time and conditions are controllable and the data is precise. We can also test samples with a larger size - which can better protect the immovable cultural heritage," Liu said.
Dunhuang Academy is now also using digital technology to record all the paintings and sculptures in the Dunhuang Mogao Grottoes in order to permanently preserve the relics in the database.
The Dunhuang Academy started its digitization project in the 1990s to create digital versions of the Mogao Grottoes and other grotto temples and has accumulated massive digital cultural resources.
With digital technology, murals, grottoes, painted sculptures and other splendid cultural heritage items have been reproduced and thus are able to be shared with the world.
New technologies protect ancient Buddhist artwork in Dunhuang caves, cliffs
