By Upasana Bhattacharjee
Suez, a French company which operates in water treatment and waste management, is set to design an artificial wetland to clean water from a petrochemical industrial area (Shanghai Chemical Industrial Park) in Shanghai. The constructed wetland technology will be based on the treatment capabilities of naturally occurring aquatic eco-systems.
The 36-hectare zone will clean the water in one of the largest petrochemical industrial regions in Asia. The estimated cost of renovating 13 hectares of existing wetlands, and adding another 23 hectares will require an estimated 18.5 million euros ($19.7 million).
Technology for the future: Artificial wetlands is the way forward
[su_pullquote align=”right”]The approach of purifying water through constructed wetlands is an optimistic prospect as it eliminates micro pollutants while preserving the biodiversity of the area.[/su_pullquote]
Suez has been looking into artificial wetlands for wastewater treatment for a few years now through its ZHART research project. The technology was first tested by Suez at a site in France in 2009. The approach of purifying water through constructed wetlands is an optimistic prospect as it eliminates micro pollutants while preserving the biodiversity of the area. The features of all such wetlands differ, depending on various factors like biodiversity and social and territorial constraints. Further, they differ in size, form, design and performance depending on the zones.
The constructed wetlands are modeled on natural aquatic eco-systems. In this setup, water is cleaned over time, and the various places (woodlands, grasslands) it passes through act as sponges. The water in these constructed wetlands flows through vegetation and over the sediment. The micro pollutants present in the water are acted upon by periphyton, or the layer of bacteria, fungi and algae above the bottom sediments. Nutrient retention can be manipulated in constructed wetlands.
The constructed wetlands are often linked with natural wetlands for optimization.
This wastewater management technique is used extensively in developing countries like Philippines, Thailand and Burma. Efforts in this direction were started off by trying to restore the naturally occurring wetlands. Following this, scientists investigated mechanisms to model artificial wetlands along the same principles. Hence, this development cannot be seen independent of the disruption that human developmental activities have caused to the sustenance of the ecosystem of wetlands.
Making this technology further relevant, the research and investment in the technology is expanding. This reflects the optimism that environmental activists and industries share about it.
Meddling with the wetlands: Cost cutting necessary to make the technology accessible
The maintenance costs for artificial wetlands are lower than the other treatment systems. However, the initial investment in such projects is considerably high. This figure shoots further up considering the huge territorial area they require along with land prices. Given that the initial capital investment is high, the accessibility of the technique becomes a major concern. The technology is efficient in terms of controlling pollution and treating wastewater. However, making it cost-effective to increase its accessibility and availability for household or agricultural waste management is difficult, thus restricting it to industrial areas for the most part.
The constructed wetlands are modeled on natural aquatic eco-systems. | Photo courtesy: Global Times[su_pullquote align=”right”]Constructed wetlands are solutions to the major environmental issue of combating pollution while also presenting a possibility of restoration and preservation of biodiversity.[/su_pullquote]
Constructed wetlands present themselves as a solution to the major environmental issue of combating pollution along with the possibility of restoration and preservation of biodiversity. In communities, small constructed wetlands serve as natural eco-systems.
While the technology is self-sustaining and includes negligible lifetime costs, its initial investment is significantly high. This limits its availability currently. Suezs contract for constructing the artificial wetland is a much-needed measure for making development sustainable. The technology looks extremely promising given the surge in research and investment in the field, along with a growing environmentally conscious population.