Abstract
Goal, Scope and Background
Nowadays, every strategy must be developed taking into account the global impact on the environment; if this aspect is forgotten, a change of environmental loads or their effect will be caused and no reduction will be attained. For instance, a wastewater treatment plant (WWIP), which is considereda priori as an ecological treatment system, gives rise to an environmental impact due to its energy consumption, use of chemical compounds, emissions to the atmosphere and sludge production, the post-treatment of which will also have diverse environmental effects. The goal of this study is to evaluate the potential environmental impact corresponding to a municipal WW1P and to identify the hot spots associated with the process.
Methods
In this study, the Centre of Environmental Science (CML) of Leiden University methodology has been considered to quantify the potential environmental impact associated with the system under study. A comprehensive analysis of the WWTP was evaluated for the physico-chemical characterisation of the wastewaters as well as the inventory of all the inputs (energy, chemical compounds, ...) and outputs (emissions to air, water, soil and solid waste generation) associated with the global process. Regarding Life Cycle Inventory Assessment, SimaPro 5.0 was used and in particular CML factors (updated in 2002) were chosen for characterisation and normalisation stages.
Results and Discussion
A comprehensive inventory of empirical data from water, sludge and gas flows during 2000 and 2001 was obtained. Two impact categories arise due to their significance: eutrophication and terrestrial ecotoxicity. Consequently, the aspects to be minimised in order to reduce the environmental impact of the system are the pollutant load at the watercourse discharge (mainly NH3, PO4 [3- and COD, even when all of them are below legal limits) and the emissions to soil (mainly Cr, Hg and Zn, even when they are present in low concentrations) when the sludge is used for agricultural application.
Conclusions
As far as the environmental impact is concerned, differentiation between humid and dry season is not required as results are practically equal for both situations. Water discharge and sludge application to land have turned out to be the main contributors in the environmental performance of a WWTP. Regarding the former, the removal of nitrogen by means of a nitrification-denitrification system coupled to conventional biological aerobic treatment implies a high environmental impact reduction and, as for the latter, bearing in mind the proposed legislation, heavy metals as well as pathogens are supposed to be the key parameters to define the most adequate treatment strategies for the generated sludge.
Recommendations and Outlook
This study can serve as a basis for future studies that can apply a similar policy to a great number of wastewater facilities. Besides, features such as different treatment systems and capacities can provide additional information with the final aim of including the environmental vector in the decision-making process when the operation of a WWTP is intended to be optimised. Moreover, sludge must also be a focus of attention due to the expected increase and its major contribution to the global environmental impact of a WWTP, which can determine other treatment alternatives.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
References
Tillman AM, Svingby M, Lundstrom H (1998): Life Cycle Assessment of municipal waste water systems. Int J LCA 3 (3) 145–157
Lundin M, Bengtsson M, Molander S (2000): Life Cycle Assessment of wastewater systems: influence of system boundaries and scale on calculated environmental loads. Environ Sci Technol 34 (1) 180–186
Vidal N, Poch M, Marté E, Rodréguez-Roda I (2002): Evaluation on the environmental implications to include structural changes in a wastewater treatment plant. J Chem Technol Biotechnol 77, 1206–1211
Suh Y J, Rousseaux P (2002): An LCA of alternative wastewater sludge treatment scenarios. Resources, Conservation and Recycling 35 (3) 191–200
Strauss KI, Wiedemann M (2000): An LCA study on sludge retreatment processes in Japan. Int J LCA 5 (5) 291–294
Suh YJ, Rousseaux P (2001): Considerations in Life Cycle Inventory analysis of municipal wastewater treatment systems. Oral presentation at COST 624 WG Meeting, Bologna
APHA-AWWA-WPCF (1985): Standard Methods for examination of water and wastewater. Washington
Vilas-Cruz M, Gómez J, Méndez R, Lema JM (1994): Determinatión simultánea de NO2-y NO3- en aguas residuales por electroforesis capilar. III International Symposium of Analytical Methodology for the Environment, Vol. H, Barcelona
NIST, National Institute of Standards and technology (1995): NIST SRM 2781 Dried Domestic Sludge. United States Government Printing Office, Washington
Real Decreto 1310/1990, de 29 de octubre, por el que se regula la Utilización de los Lodos de Depuratión en el Sector Agrario. BOE 262/1990
PRé Consultants (2001): SimaPro5 Manuals: Database Manual Methods. Amersfoort
Ullmann F (1997): Ullmann’s Encyclopedia of Industrial Chemistry
IDAE: Instituto para la Diversification y Ahorro de la Energia. http://www.idea.es
BUWAL250 (1996): Ökoinventare für Verpackugen. Bern
Henze M, Harremoes P (2000): Wastewater treatment: Biological and chemical processes. Springer, Berlin
Hannigan M. (2003): Sources of air pollution. Oral presentation at Air Pollution Controls Course, Colorado
ISO (2000): ISO 14000. Environmental Management. Genève
Guinee JB, Gorreé M, Heijungs R, Huppes G, Kleijn R, de Koning A, van Oers L, Weneger A, Suh S, Udo de Haes HA, de Bruijn H, van Duin R, Huijbregts M (2001): Life Cycle Assessment: An operational guide to the ISO standards. Leiden
Potting JMB (2000): Spatial Differentiation in Life Cycle Impact Assessment. A Framework, and Site-Dependent Factors to Assess Acidification and Human Exposure. PhD Dissertation by University of Utrecht
Krewitt W, Bachmann TM, Heck T, Trukenmüller A (2001): Country-specific Damage Factors for Air Pollutants. A Step Towards Site Dependent Life Cycle Impact Assessment. Int J LCA 6 (4) 199–210
Huijbregts MAJ, Breedveld L, Huppes G, de Koning A, van Oers L, Suh S (2003): Normalisation figures for environmental life-cycle assessment The Netherlands (1997/1998), Western Europe (1995) and the world (1990 and 1995). J Cleaner Production 11 (7) 737–748
Sörme L, Lagerkvist R (2002): Sources of heavy metals in urban wastewater in Stockholm. The Science of the Total Environment 298, 131–145
Mattson J, Avergård I, Robinsson P (1991): Priority pollutants, heavy metals and main constituents in the domestic sewage from two residential areas in Gothenburg. Vatten 47, 204–211
Lindqvist-Östblom A, Sörme L, Söderberg H (2001): Substance flow analysis as a tool to support environmental management of heavy metals in wastewater treatment companies, Oral presentation at Economic growth, material flows and environmental pressure at Folkets Hus in Stockholm
Sörme L, Lindqvist A, Söderberg H (2003): Capacity to influence sources of heavy metals to wastewater treatment sludge. Environmental Management 31 (3) 421–428
Hospido A, Martin M, Rigola M (2003): Comparison of sewage sludge disposal scenarios using life cycle assessment. Oral presentation at Environment 2010: Situation and Perspectives for the European Union, Porto
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Hospido, A., Moreira, M.T., Fernández-Couto, M. et al. Environmental performance of a municipal wastewater treatment plant. Int J LCA 9, 261–271 (2004). https://doi.org/10.1007/BF02978602
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02978602