Environmental assessment of urban wastewater reuse: treatment alternatives and applications.

The main function of a Wastewater Treatment Plant is to minimize the environmental impact of discharging untreated water into natural water systems. Also a Wastewater Treatment Plant may get a resource from wastewater carrying out a tertiary treatment on the treated wastewater which can be reused in non-potable applications. Water reuse strategies are intended to address the problem of water scarcity without aggravating other environmental problems, thus reflecting the need of their environmental assessment. In this paper we used Life Cycle Assessment to evaluate different disinfection treatments (chlorination plus ultraviolet treatment, ozonation and ozonation plus hydrogen peroxide) and to assess the environmental advantages and drawbacks of urban wastewater reuse in non-potable applications. To do so, we compared the environmental impacts of producing 1m(3) of water for non-potable uses from reclaimed water, potable water and desalinated water sources. The calculation has used current operating data from a Wastewater Treatment Plant located in the Mediterranean area, although the results can be applied to any other plant with similar technology. The ozonation and ozonation plus hydrogen peroxide disinfection treatment technologies have similar environmental profiles. However most of the indicators are about 50% higher than the ultraviolet disinfection except for the acidification (100% higher) and photochemical oxidation (less than 5%). Non-potable uses (both agricultural and urban uses) of reclaimed water have environmental and economical advantages. Reuse of treated wastewater is particularly beneficial when it can replace desalinated water. Consequently, reclaimed water should be promoted for non-potable uses, when there is scarcity of freshwater.

[1]  L Sala,et al.  Towards sustainability in water recycling. , 2004, Water science and technology : a journal of the International Association on Water Pollution Research.

[2]  M. Ortiz,et al.  Life cycle assessment of water treatment technologies: wastewater and water-reuse in a small town , 2007 .

[3]  S Lundie,et al.  Integrated environmental assessment of tertiary and residuals treatment--LCA in the wastewater industry. , 2003, Water science and technology : a journal of the International Association on Water Pollution Research.

[4]  A. D. Benetti Water reuse: issues, technologies, and applications , 2007 .

[5]  Takashi Asano,et al.  Peer Reviewed: Recovering Sustainable Water from Wastewater , 2004 .

[6]  I. Muñoz,et al.  Life Cycle Assessment of urban wastewater reuse with ozonation as tertiary treatment: a focus on toxicity-related impacts. , 2009, The Science of the total environment.

[7]  Francesc Castells,et al.  LCA as a decision support tool for the environmental improvement of the operation of a municipal wastewater treatment plant. , 2009, Environmental science & technology.

[8]  Montse Meneses,et al.  Alternatives for Reducing the Environmental Impact of the Main Residue From a Desalination Plant , 2010 .

[9]  Mark A J Huijbregts,et al.  Ranking potential impacts of priority and emerging pollutants in urban wastewater through life cycle impact assessment. , 2008, Chemosphere.

[10]  T. Asano,et al.  Recovering sustainable water from wastewater. , 2004, Environmental science & technology.

[11]  Donghee Park,et al.  Environmental and economic feasibility study of a total wastewater treatment network system. , 2008, Journal of environmental management.

[12]  I. Muñoz,et al.  Reducing the environmental impacts of reverse osmosis desalination by using brackish groundwater resources. , 2008, Water research.

[13]  Sverker Molander,et al.  Sustainable development indicators for wastewater systems – researchers and indicator users in a co-operative case study , 2005 .

[14]  Luis M. Serra,et al.  Life cycle assessment of MSF, MED and RO desalination technologies , 2006 .