French utility company SUEZ has won a design contract for the rehabilitation and expansion of the discharge constructed wetland at the Shanghai Chemical Industry Park (SCIP), the largest petrochemical platform in Asia. The contract, which represents an investment of €18.5 million, is SUEZ’s first Zone Libellule project in Asia and the largest for treating industrial wastewater.
Since 2002, SUEZ has been overseeing the industrial wastewater treatment and water supply for Shanghai Chemical Industry Park. In addition, the company also handles the treatment and recovery of hazardous waste since 2006.
The new contract aims to rehabilitate the existing 13 hectares of discharge constructed wetland and to design a 23 hectares’ expansion. The zone is located downstream of the wastewater treatment plant operated by SUEZ. Not only is it designed to achieve tertiary treatment of effluents, but it also includes guarantees for the elimination of pollutants, improving the quality of the water discharged into the environment and hence, allowing for re-use. Construction will begin in mid-2017, and the zone will be launched in 2018.
This Zone Libellule is the result of a unique engineering concept developed by SUEZ, which uses the treatment capabilities of the natural environment. The design of the SCIP project draws on feedback from the Zone Libellule pilot project—first put into operation in 2009 at the municipal wastewater treatment plant in Saint Just (Hérault, France)—as well as insights from the ZHART (Zones Humides ARTificielles (“Artificial Wetlands”)) R&D project (2012–2016), which was managed by the CIRSEE, the main research centre at SUEZ. Five years of research have allowed the Zone Libellule concept to enhance by optimising its design based on the micro- and macropollutants treatment goals and the local context.
This ecological engineering innovation will help improve the quality of SCIP’s treated wastewater, as measured by several industrial effluent pollution parameters: Chemical Oxygen Demand (COD), metals, phosphorus, nitrogen, and more. Several hundreds of plant species will also be chosen based on their treatment capabilities, their salinity tolerance (owing to the high level of salinity in the park’s effluents) and their ecological characteristics. The diversity of habitats created will allow for colonisation by local plant and animal species adapted to live in wetlands.
The project is part of SUEZ’s initiative to support the Chinese authorities in developing solutions to conserve water resources, protect the environment and anticipate regulatory requirements. This constructed wetland is an example of circular economy, as it allows the re-use of wastewater and promotes the generation of renewable energy from solar panels and wind turbines, enabling the Zone Libellule to be self-sufficient in energy.