WUHAN, March 9 (Xinhua) -- At a deserted factory, excavators take down cement structures while workers use electric saws to break down metallic parts and load them onto trucks. In fifty days, the 40-year-old factory will become empty ground.

Tiantian chemical factory is located at the southern bank of the Yangtze River in Yichang City in central China's Hubei Province. Since last year, a total of 25 factories have been shut down as the city government moves polluters away from the longest river in China.

"By the end of April, all of this will be gone," said Li Xianyun, general manager of the company, pointing to emptied factory buildings and deserted chemical containers.

The company used to be one of the major tax payers in the city. It paid over 28 million yuan (about 4.4 million U.S. dollars) in taxes every year before closure.

"We did not want to move, but it is the right thing to do to reduce pollution in the river," said Li.

China issued a development plan for the Yangtze River Economic Belt in September 2016 and a guideline for green development of the belt in 2017. The Yangtze River Economic Belt consists of nine provinces and two municipalities that cover roughly one-fifth of China's land.

Yichang, which has rich phosphorous resources, is a major chemical industry base in Hubei. Many of the chemical manufacturers are located near the Yangtze River because being on the waterway cuts transportation costs.

"We are giving a strong push for the chemical industry to upgrade. It is like a warrior cutting off a limb to save the body," said Guo Kangxin, director of the city's reform and development commission.

In September last year, Yichang government issued a document on cutting pollution and upgrading the chemical industry. By 2020, a total of 134 chemical firms will be shut down, relocated or renovated. No factories will be allowed within one kilometer of the Yangtze River.

"The ultimate aim of economic development is to improve the lives of the people. We must make environmental protection a priority," said Zhou Ji, secretary of the Yichang City Communist Party Committee.

After the dismantling of Tiantian chemical plant, a new plant worth 10 billion yuan will be built in Zhijiang City, administered by Yichang. A high-quality chemical park is under construction in Zhijiang, away from the Yangtze River.

"The future of the chemical industry is green and recycling," said Chen Xiaoqing, assistant general manager of Hubei Xingfa Chemicals Group Co., Ltd. The company produces glyphosate, a by-product of the process is chloromethane, which is used for the production of organic silicon. Hydrochloric acid, a by-product in the process of producing organic silicon, is then recycled to produce glyphosate.

"Pollutants are misplaced resources," said Chen. The company recycles all its solid wastes, 98 percent of its waste gas and 90 percent of its waste water.

Chemical industry accounted for 19.8 percent of Yichang's industrial output in 2017, down from 30.6 percent in 2016, according to Mayor Zhang Jiasheng.

Last year, fixed asset investment and local fiscal revenue dropped by 10 percent year on year in Yichang.

But water quality in the rivers flowing through the city, where four million people live, has improved, and air quality has also improved, said Zhang.

The city is focusing on developing the fine chemicals industry and trying to diversify by bringing in new industries such as electronic and information technology, biomedicine and high-end equipment manufacturing.

"We must not sacrifice the environment for development. We have to abandon the obsession with growth and seek sustainable development," said the mayor.