Guiyang Radio and Television Station | Guiyang: Exploring sewage reuse in sunken reclaimed water plant for low-carbon development ​

  Water environment protection and management represent both a project crucial for livelihoods and a commitment spanning generations.In recent years, Guiyang has proactively delved into the reuse of sewage from sunken reclaimed water plants, effectively addressing sewage treatment challenges, mitigating environmental pollution, and significantly contributing to the carbon neutralization of sewage treatment facilities.

Above, the bridge spans over babbling streams, adorned by the vibrant tapestry of green trees and blooming flowers; below, hidden currents whisper, accompanied by the rhythmic symphony of machinery.Stepping into the third phase project of the Jinyang Reclaimed Water Plant on the left bank of the Baila River in Guanshanhu District, the expansive 32 mu area of the project surprisingly carries no trace of sewage odor.Through a comprehensive process involving pretreatment, biological treatment, advanced treatment, ultraviolet disinfection, sludge treatment, and more, a remarkable 80,000 tons of sewage are rejuvenated here daily.

  Luo Qing, Deputy Director of the Jinyang Reclaimed Water Plant at China Water Environment, proudly stated that their discharge standard meets the Class IV water body standard. A significant portion of the discharged water is dedicated to river landscape water replenishment, while the remaining portion undergoes reclaimed water reuse. The repurposed sewage is utilized for central heating and cooling, contributing to energy savings and reduced consumption.

  Harnessing the "waste heat" from sewage to achieve eco-friendly heating and refrigeration marks a breakthrough in the sewage treatment processes of Jinyang Reclaimed Water Plant Phase III.It is known that the water temperature of "reclaimed water" after harmless treatment has strong stability. In the third phase of Jinyang Reclaimed Water Plant, the water source heat pump system is employed to extract latent hot and cold energy from the reclaimed water. This system efficiently provides heating and cooling to the adjacent office area of the water plant.

  Cao Xiaoxin, Deputy General Manager of the Engineering Technology Center at China Water Environment, noted that the integration of sinking plants within the urban landscape facilitates the replacement and utilization of heat and cold energy in sewage, showcasing the adaptability and efficiency of this approach.

  Guiyang, as the pioneer in China to establish a city-scale sunken sewage treatment ecosystem, has successfully constructed 17 sunken reclaimed water plants along the Nanming River Basin. These plants contribute 500 million cubic meters of reclaimed water annually to the Nanming River, establishing reclaimed water as a dependable second water source for the river.The China Water Environmentis set to collaborate with Guiyang China Railway Construction and Real Estate Development Co., Ltd. The Jinyang Reclaimed Water Plant Phase 3 project will serve as a pilot initiative, facilitating the transfer of recycled water from the plant to nearby communities, including China Railway Shanghe Jincheng Community. This strategic move aims to harness the reuse potential of recycled water and drive the organic renewal of the city.

  Luo Qing, Deputy Director of Jinyang Reclaimed Water Plant at China Water Environment, shared that their comprehensive office building has been utilizing sewage for central heating and cooling since its implementation in 2019. The system has operated consistently and reliably since its inception. The company has extended its coverage to the real estate surrounding Guanshan Lake and is actively engaged in preliminary construction and exploration.

  The China Water Environment, through the innovative system planning and governance concept of "moderate concentration, local treatment, and nearby reuse", has revolutionized the traditional approach of large interception and terminal centralized treatment. This transformation led to the establishment of an advanced technology system, the distributed sunken reclaimed water ecosystem, for sewage treatment and resource utilization. This initiative not only resulted in savings on operational costs and investments in pipe network construction but also contributed significantly to the realization of green and low-carbon development in the city. TheCollection of Typical Cases of Carbon Peak and Carbon Neutralization in Urban and Rural Construction,compiled by the Technology and Industrialization Development Center of the Ministry of Housing and Urban-Rural Development, was recently released. Notably, the Guiyang distributed sunken reclaimed water ecosystem by China Water Environmenthas earned its place among the first batch of low-carbon cases featured in the collection.

Cao Xiaoxin, Deputy General Manager of the Engineering Technology Center at China Water Environment, expressed appreciation for this acknowledgment, considering it a significant encouragement.Looking ahead, the group plans to intensify efforts in reclaimed water reuse under the guidance of the water management department. Leveraging the advantages of sunken plants, the aim is to maximize the energy utilization of sewage, further decrease the energy consumption of sewage treatment plants, and reduce carbon emissions. The overarching goal is to establish Guiyang as a model for sewage recycling and green, low-carbon development, sharing replicable experiences for nationwide benefit.