Colorful Guizhou Network | How can Guiyang sewage be reborn? There are secrets under the park

In the past, when it came to sewage treatment plants, many people's first reaction was often "dirty, messy, and smelly". Residents generally do not want to be neighbors with such projects, resulting in the phenomenon of "avoidance of neighbors", that is, "building can be done, but not in my backyard".

The distributed sinking regenerated water ecosystem adopts the technological concept of "environmentally friendly, land intensive, and resource utilization", integrating environmental pollution control, land resource utilization, and public product supply, achieving "one land, three layers, and multiple uses". The sewage treatment is completed underground, and landscape water parks, sports fields, children's entertainment facilities, etc. are built on the ground, occupying only one-third of the land of traditional surface sewage treatment plants, significantly reducing land and pipeline investment, and effectively solving the problem of "avoiding neighbors".

April 22nd is World Earth Day. Follow the reporter to three sunken reclaimed water plants of China Water Environment Group to see what these plants hidden under the park look like and what role they will play?

The roof of the sewage treatment plant is actually a park

On a spring morning, in the Qingshan Reclaimed Water Plant Live Water Landscape Park on Jiefang West Road in Nanming District, Guiyang City, many white egrets wander by the water or dance gracefully at low altitude; Amidst the reeds, clear landscape water flows slowly alongside the waterwheel

This seems no different from a regular park, but beneath the park lies a reclaimed water plant.

Dai Xuesheng, 73 years old this year, lives in the Harmony Home community across from the Huoshui Landscape Park. He watched as the Qingshan Reclaimed Water Plant was built, and he keeps a thrush bird. Every day, he takes walks with his neighbors in the park.

Ground park above Qingshan Reclaimed Water Plant

If we don't talk about it, it's difficult to link the park with the sewage treatment plant. There's no impression of the foul odor and noise from the sewage treatment plant, "said Dai Xuesheng. At the beginning of the construction of the sewage treatment plant, he held an opposing view, which was" the farther the better. Now, with the completion and operation of the Qingshan Reclaimed Water Plant, my thoughts have also changed. "This is indeed a major project that benefits the people. Building the sewage treatment plant underground not only saves land, but also does not affect living. Moreover, there is also a place where we can get close to nature, play, and take a walk. We are all very satisfied

Qingshan Reclaimed Water Plant is the first sunken sewage treatment plant in Guizhou Province. It began construction in early 2014 and was put into operation at the end of the same year. It covers an area of 32 acres and has a daily sewage treatment capacity of 50000 cubic meters.

Since it is the first sunken reclaimed water plant in the province, what are the mysterious aspects of the underground part?

Under the leadership of Hao Wenlei, the director of Qingshan Reclaimed Water Plant, the reporter walked through an underground corridor about 400 meters long and arrived at the basement level of the sunken factory area. The first thing that caught the eye was a large passage that was as wide as 4 meters. The combination of natural light above and wall lights made the entire factory area bright and transparent, without any underground gloom.

Internal sewage treatment facilities in the factory area

“Our sewage treatment needs to go through three major stages, pretreatment, efficient biochemical treatment, and deep treatment, and finally become regenerated water that can be reused, "said Hao Wenlei. The treated water can reach the surface level IV standard.

Why can't you smell the odor? Faced with the reporter's doubts, Hao Wenlei gave the answer.

When sewage comes in, the odor it carries is all sucked into this collection pipe through a high-power exhaust fan, treated separately, and then released into the atmosphere through an exhaust tower after reaching the standard. Therefore, in this factory area, there is no odor to be smelled, whether on the ground or underground. "Hao Wenlei pointed to a blue pipe at the top of the factory area and explained that the underground water plant is a fully enclosed box, which can better" lock "all odors and noise.

The advantages of sunken sewage treatment plants include less land occupation, no noise, and no odor, which can effectively solve the "neighbor avoidance effect". At the same time, the open landscape park above the factory area uses 90% recycled water treated with sewage as the landscape water source, which can effectively save water and improve the quality of the city.

Reclaimed water is used for heating and cooling in office buildings

Under the Xiaowanhe Bridge in Yeya Township, Yunyan District, Guiyang City, a glass structure building lies quietly in the green space. The trail winds and turns, with green lawns and swaying flowers along the way... Few people know that this is Jinyang Reclaimed Water Plant.

Zhou Fubo, the director of Jinyang Reclaimed Water Plant, introduced that the plant is divided into three phases, covering an area of 125 acres, with a daily processing capacity of 180000 tons.

Overview of Jinyang Reclaimed Water Plant

During the interview, Zhou Fubo invited reporters to the office building to experience "summer" in advance.

The cold air you feel here is the sewage source heat pump station technology introduced by our factory, "Zhou Fubo said. Generally, after the sewage is treated to meet the standards, it will be discharged into rivers. However, before that, the sewage in the factory also needs to utilize" waste heat "to achieve" green "heating.

Wastewater can be used for heating or cooling, which sounds a bit unbelievable. How is this actually achieved?

By utilizing urban domestic sewage, industrial wastewater, and other materials that have been properly treated to meet certain water quality standards, it becomes a beneficial water substitute for tap water and surface natural water for non drinking purposes, commonly known as' reclaimed water ', "explained Zhou Fubo. The reclaimed water can be treated through a water source heat pump system without the need for a cooling tower

The temperature of reclaimed water in winter is generally 23 to 24 degrees, much higher than the air temperature. In summer, the temperature is generally 16 to 18 degrees, much lower than the air temperature, "said Zhou Fubo. However, because a water source heat pump is installed, reclaimed water can be transported to office buildings in winter and summer, and the temperature difference between reclaimed water and air can be utilized to achieve heating and cooling effects.

Subsequently, Zhou Fubo took the reporter to visit the heating and cooling machine room. The entire factory floor was clean and tidy, and there was no odor in the air.

Originally, this was the "brain center" of the factory's sewage source heat recovery and utilization project. The sewage source heat pump system extracts heat from the sewage, converts it into heat, and releases energy in the heating system, effectively ensuring a warm environment in winter and cool environment in summer for the office building.

The entire sewage source heat pump system does not consume tail water and does not cause pollution to the environment, other equipment, and water systems. It turns sewage into high-quality 'green energy', "said Zhou Fubo. This is similar to installing a" central air conditioning "in the entire area to provide heating and cooling to every household. Calculated, the annual operating cost is only 40% to 70% of traditional centralized energy supply systems, which can reduce investment by more than 40% compared to self built air conditioning systems and lower usage costs by 15% to 30%.

In 2021, China Water Environment Group collaborated with Guiyang China Railway Construction and Real Estate Development Co., Ltd. to transport the harmless treated "recycled water" from the factory to the China Railway Shanghe Jincheng residential area. The heat exchange device is used to provide heating and cooling for residents in the residential area, and the recycled water is returned to the original water body without polluting the water quality.

At present, there is no large-scale use of this sewage source heat pump for centralized heating and cooling in Guiyang city. The group plans to use this project as a pilot to explore the feasibility of this approach.

Cut off the pollution from the source and let the gurgling water flow into the river

Daily treatment of 50000 tons of sewage, with a 100% reuse rate, and an annual ecological replenishment of 18 million cubic meters to the Nanming River, "said Li Tengjiao, the director of the Hebin Reclaimed Water Plant.

The Hebin Reclaimed Water Plant is located near the Nanming River in Hebin Park, Nanming District, Guiyang City, covering an area of 27.75 acres. Although the land area has been reduced, the sewage purification and treatment capacity has not been compromised.

Following the road of the sewage treatment plant workshop, sedimentation tanks, disinfection tanks, mud storage tanks, etc. are arranged in an orderly manner. Due to the use of efficient biological deodorization technology, the entire production operation is odorless.

Comparison of water quality (with purified water on the left and treated wastewater on the right)

Here, all sewage undergoes three stages of physical treatment, biochemical treatment, and chemical treatment to turn from turbid to clear, and finally reaches the surface Class IV water quality standard before being discharged into the left bank of Nanming River as ecological supply water, "said Li Tengjiao.

In addition to ecological water replenishment for rivers and lakes, the Riverside Reclaimed Water Plant has also significantly improved the water quality of Nanming River, effectively solving the problem of black and odorous water.

Through governance, the water quality of this river has been greatly improved. Now that we can see such clear river water, it shows that our urban environment is getting better and better, "said Zhang Suzhen, a resident of Guiyang who is taking a walk by the Nanming River.

How was this achieved?

Li Tengjiao introduced that in the past, the governance model of Nanming River was "large interception and discharge, large concentration". The construction of the pipeline network was difficult, the construction difficulty was high, the investment in land acquisition and demolition was large, and the ecological base flow of the river was low. Nanming River has long faced problems such as downstream water diversion pressure, and has fallen into a stalemate of "repeated governance and pollution".

After conducting systematic research on the water environment of Nanming River, China Water Environment Group proposed a governance path of "moderate concentration, nearby treatment, and nearby reuse". Sewage treatment plants will be built locally in areas with high sewage volume along the main and tributaries of Nanming River, which can optimize the utilization of land and water resources.

The Riverside Reclaimed Water Plant is located near the Nanming River in Riverside Park

It is reported that the water in the riverside park pool, as well as the water used for watering trees, flowers, and plants, all come from the tail water discharged from underground sewage treatment plants. Meanwhile, a portion of the treated wastewater from the sewage treatment plant is also used for watering and cleaning urban municipal roads.

Guiyang is the first city in China to construct a sunken sewage treatment ecosystem on a city scale. Currently, there are 34 reclaimed water plants in the Nanming River Basin, including 17 sunken reclaimed water plants, which replenish 500 million tons of ecological water to the Nanming River every year, "said Gao Lin, Assistant Chief Executive Officer of China Water Environment Group and General Manager of Guizhou Business District.

Now, the water quality of Nanming River has reached the surface Class IV water standard, and 80% of the time the national control section has reached Class III. According to Gao Lin's introduction, after calculation, through the distributed sinking regenerated water ecological technology, more than a thousand acres of land have been saved for Guiyang City, and the annual provincial water transfer fee has been reduced by 158 million yuan. This not only solves the problem of urban water resource shortage, but also reduces the leakage and environmental risks caused by long-distance underground transportation of sewage pipelines.

Now, walking by the Nanming River, white egrets dance gracefully, fish swim in the shallow bottom, and the trees and flowers on the shore are fragrant.

Related links

Entering the World of Water and Exploring the Secrets of Green

The Guiyang Water Environment Science Popularization Museum is located in the first above ground active water landscape park in Guiyang, next to the Wuyan Bridge on the Nanming River, with the Qingshan Sewage Treatment Plant underground.

It is reported that the Science Popularization Museum is open to the public for free, covering an area of 1600 square meters and having a total of 9 exhibition halls. It mainly displays the water culture, water resources situation, government measures to protect the water environment, as well as water resource conservation, scientific experiments and other content in Guiyang City; The ground active water landscape park integrates the concept of sponge city, and the water body adopts the method of "reclaimed water reuse". The "reclaimed water" treated by Guiyang Qingshan Reclaimed Water Plant is used as the supplementary water for the landscape park, which not only achieves the purpose of regeneration and water resource conservation, but also plays a role in popularizing and showcasing water environment protection and water ecological technology.

At present, science museums have become an important way and window for the general public in Guiyang to understand water culture, learn water knowledge, and explore water technology.

Journalist's note

Wastewater is reborn, making the city more beautiful.

In recent years, Guiyang City has actively explored the construction of recycled water plants, improved the capacity of sewage treatment and recycling, and solved a series of problems such as water ecological governance and water environmental protection. These regenerated water plants that have emerged not only solve the problem of sewage treatment in the service area, but also provide strong support for ecological water replenishment and treatment of black and odorous water bodies in the jurisdiction, making the further reuse of regenerated water more economically valuable.

At present, the sunken reclaimed water plants in Guiyang are operated through the model of underground factory construction and ground park construction, which solves the problem of land shortage in mountainous cities and provides residents with a good place for leisure tourism. At the same time, it sends an environmental signal of loving and protecting water.

In the future, with the control of the total increase in urban water consumption, it is believed that the efficient utilization of recycled water will promote the harmonious coexistence between humans and nature.