Life cycle assessment and wastewater treatmentapplications and methodological improvements

  1. Rodriguez Garcia, Gonzalo
Dirixida por:
  1. Gumersindo Feijoo Costa Director
  2. Almudena Hospido Quintana Director

Universidade de defensa: Universidade de Santiago de Compostela

Fecha de defensa: 18 de outubro de 2013

Tribunal:
  1. Luis Arroja Presidente/a
  2. Juan M. Garrido Fernández Secretario
  3. Francesco Fatone Vogal
  4. M. Asunción Antón Vallejo Vogal
  5. Xavier Gabarrell Durany Vogal
Departamento:
  1. Departamento de Enxeñaría Química

Tipo: Tese

Resumo

The environmental importance of the aquatic environment is defined not only by the life it supports but due to the fact that its presence and quality affects in no small amount to life in other environments. However, human activity has altered those two aspects in a significant way, on one side the use of large amounts of water, on the other, its quality once it is returned to nature. In this latter point water treatment plants play a substantial role due to the fact that even when they are not the original source of impact, they are responsible for its final reduction or disposal. In the last few years Life Cycle Assessment has revealed itself as a powerful tool for environmental assessment of products and processes from a holistic point of view, allowing the substitution of the conventional end of line point of view for a cradle to tomb one. Its application to water treatment started in 1997 with the publication of the research done by Roeleveld et al. on which the impact of the whole Netherlands' population as a function of their water treatment level was assessed. Studies that followed covered very different topics although an emphasis on comparative analysis has been done: comparisons between different treatments for fecal water and urine and conventional configurations (Tillman et al., 1998; Lundine et al. 2001, Maurer et al., 2003), between different technologies (Vidal et al., 2002; Høibe et al., 2008) or between treatment plants (Gallego et al., 2008; Hospido et al., 2008) From a methodological point of view it is necessary to stress the work done by Renau et al. (2008) where the differences that can appear during the comparison of two water treatment technologies thought different life cycle analysis methodologies are highlighted. From a whole water cycle point of view it is revealing the study done by Lassaux et al. (2005) since the different activities that take place between the pumping station and the wastewater treatment plant where taken into account. The present thesis project wants to contribute to the optimization of both water treatment technologies design and operation from a point of view that includes the environmental vector as an element in decision making. This general objective will be divided in two basic axis: 1.Methodological. Review the principles of the methodology in the case of study. Integration of statistical methods such as Data Envelope Analysis will be taken into account. 2.Practical. With the methodology developed in the latter section different water treatment technologies will be studied including some that nowadays are mostly as pilot plants: membrane bioreactor, nutrient precipitation with struvite etc, as a way to compare those advanced treatments with conventional technologies and for validation of their environmental benefits. Once those objectives are fulfilled, this thesis will study the contribution of water treatment plants in the global plumbing system, broading the study limits over the treatment facilities and comparing the environmental behavior of separative and non separative systems as a way of improving the current wastewater management model.