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Wenzhou, China Builds Asia's Largest Underground Sewage Treatment Plant

The existing treatment plant, Wenzhou, Zhejiang, China

What should a sewage treatment plant be like? A criss-cross of pipelines, large pools and pungent smells? The Wenzhou plant will then subvert your imagination. According to the plan, once the plant is completed, the site will look like a gigantic park. The main part of the plant occupies an area of 85 acres, which is the area of about seven football fields. The total project investment is about 680 million Yuan (about 1.05 million USD.) Around the plant, high-end office buildings and shopping malls will be erected.

The sewage treatment plant is located in the center of Yang Fushan Tu village in Wenzhou City, at the location of the former sewage treatment plant on the eastern side. The new facility will replace the existing conventional wastewater treatment plant.

The main body of the plant will be underground. Characteristics such as compact land use, a high degree of automation and environmentally-friendly emissions, have made underground plants a go-to choice for more and more cities. In Anhui, Guizhou and other fast-growing inland cities, many sewage treatment plants are now built underground.

The biggest treatment plant design, Wenzhou, Zhejiang, China

In Wenzhou, the sewage treatment plant structures do not exceed seven meters (twenty-three feet) in height. Except for the roads, all areas will be covered in vegetation, creating a green, "invisibility cloak." The new plant will use less than 40 percent of the 287 acres of land occupied by the current sewage treatment plant.

Despite its smaller footprint, the capacity of the new sewage treatment is about twice that of the old one. "The existing sewage treatment plant can handle only 0.20 million tons of waste, and is currently overloaded," said one of Wenzhou Municipal Construction Committee officials. The new plant's capacity will be 0.4 million tons per day, and the water quality will meet the national A standard. The area that was saved, thanks to the minimal footprint of the new plant, will host high-end shopping malls and office buildings.

The union led by the Hangzhou Iron and Steel Group will be in charge of this plant's financing, design, construction, management and operation for a period of 30 years, including the construction time. The construction of the plant is expected to be completed next year.

What is special about the plant's operational system? This is still a secret. The one certain thing is that the new plant adopts technologies that are far from traditional; its operational systems are much more complex in and out.

For example, one of its core equipment will adopt the concept of "comprehensive deodorant." "A biofilter at the bottom of the sewage pools will constantly emit bubbles that will float to the surface forming layers of foam on the water. This biofilter, in addition to exhaust fans and special light bulbs, will act as deodorants," states one of the project's team members, "if someone stands in front the pool, he or she almost won't be able to smell the odor." The biochemical pool also uses biological contact oxidation; "The advantage of this technique is to reduce the dirt and other impurities. As a result, the treatment plant needs to be cleaned only once every three months."

The entire plant is almost fully automated. The core equipment is underground and is fully enclosed to prevent odors. Gazes are collected through a pipe, transported to the biological deodorization system, and discharged after treatment, to leave a no-odor treatment plant.

Is there a high-tech sewage treatment plant in your area? How is it different from traditional ones? Is your city active in developing and adopting high-tech solutions to improve its infrastructure? Share your thoughts and your city's stories in the comments area below.

The original article, published in Chinese, can be found here.

Credits: Images and data linked to sources.