Ecological safety buffer zone refers to the transition zone in ecological space that absorbs, degrades and purifies environmental pollution, resists, alleviates and reduces ecological impact, and has various functions such as water conservation, biodiversity maintenance, ecosystem stabilization and carbon neutrality. . In recent years, Jiangsu Province has continued to promote the construction of ecological security buffer zones. By constructing artificial wetlands and country parks in key watersheds such as Taihu Lake, Yangtze River, and the Beijing-Hangzhou Grand Canal, ecological barriers have been constructed according to local conditions to protect the ecological security of important and sensitive water bodies.

A few days ago, the Jiangsu Provincial Department of Finance and the Department of Ecology and Environment announced the list of awards and supplements for the provincial ecological safety buffer zone demonstration project in 2021. The Canal Suqian Port Water Ecological Treatment Project designed by the Nanjing Municipal Design and Research Institute was successfully selected.

The total investment of the Canal Suqian Port Water Ecological Treatment Project is about 570 million yuan. The construction content includes sewage treatment plant, ecological wetland and supporting pipe network. The design scale of sewage treatment plant is 90,000 tons/day, and the design scale of ecological wetland is 120,000 tons/day ( Another 30,000 tons/day comes from Yangbei Town Sewage Treatment Plant).

The project uses sewage biological treatment + advanced treatment + active coke enhanced pretreatment + ecological wetland upgrading and buffering, so that industrial wastewater is purified layer by layer, and finally reaches the surface class IV water standard. About 43.8 million m³.

The project implements the concept of wastewater resource utilization and ecological safety buffering, achieves the dual goals of zero discharge of wastewater in industrial parks and the construction of regional ecological barriers, and provides a typical demonstration for the ecological treatment and recycling of tail water.

The construction area of the ecological wetland buffer area is 493 mu, and the process of "aerated ecological pond + shallow surface flow wetland + new multi-media subsurface wetland + aquatic plant pond" is adopted. By restoring a large area of wet plants and aquatic plants, setting up multi-functional enhanced purification fillers, constructing a wetland plant-animal-microbe ecosystem, greatly reducing water pollutants, and the effluent quality reaches the surface water class IV standard (river). Through the purification of the cascade wetland system, the transformation of tail water into surface water and ecological water is realized, and the effluent is reused for industrial water in Suqian Port Industrial Park in the Canal and circulating cooling water for thermal power plants. The water ecological security of important sensitive areas such as the Beijing-Hangzhou Grand Canal and the ancient Yellow River has been improved.

In recent years, Nanjing Municipal Council has practiced the concepts of "lucid waters and lush mountains are invaluable assets" and "high-quality development", and has undertaken more than 60 wetland projects with a total investment of over 10 billion yuan. Through continuous innovation, it has completed more than 20 research projects, participated in the compilation of more than 10 norms and standards, and formed more than 30 core technology products such as advanced sewage treatment and resource utilization, composite constructed wetlands, and river and lake ecosystem construction. In the future, our institute will rely on its professional advantages in water ecological management and restoration to further expand the business of ecological safety buffer zones and the construction of happy rivers and lakes, and provide high-quality solutions for ecological safety assurance and biodiversity restoration in important river basins in various places.