http://hdl.handle.net/2117/2434 2013-06-20T05:18:25Z http://hdl.handle.net/2117/11405 Title: Tratamiento de lodos de depuradora con humedales artificiales Authors: Uggetti, Enrica; Ferrer Martí, Ivet; Castellnou, Roger; Molist, Jordi; García Serrano, Joan Abstract: Hoy en día la gestión del lodo de depuradora es un tema clave dentro del tratamiento del agua residual, representando hasta el 60% de los costes de operación de una depuradora urbana. El elevado contenido de agua del lodo encarece su gestión, justificando la necesidad de desarrollar métodos simples y económicos para reducir su volumen. Durante las últimas décadas, se ha adaptado la tecnología de los humedales construidos o lechos de macrófitos a la deshidratación del lodo. Como principales ventajas destacan una demanda energética, costes de operación y mantenimiento reducidos, y una buena integración en el paisaje. Sin embargo, el número de plantas en operación actualmente es muy reducido en comparación con los tratamientos mecánicos convencionales. En este artículo se describen las principales características y aspectos operacionales de los humedales construidos para el tratamiento del lodo, resumiendo los resultados más relevantes de la literatura. 2011-02-16T11:20:43Z http://hdl.handle.net/2117/9754 Title: Techno-economical evaluation of water reuse for wetland restoration: a case study in a natural park in Catalonia, Northeastern Spain Authors: Seguí Amórtegui, Luis Alberto; Alfranca Burriel, Òscar; García Serrano, Joan Abstract: The main interest of the methodology for the investigation of wastewater reclamation and reuse systems which is proposed in this paper is that all costs and benefits (social and private) are considered in the economic and technological analysis. This general concern allows an improvement in the design of investment decisions. Traditionally, an economic-financial analysis of wastewater reclamation and reuse systems focuses exclusively on the study of costs and private benefits. The methodology that is presented in this paper takes into account not only the private impacts but also the project spillovers which could have relevance on the project. In this research, the use value of the reclaimed water in the Natural Wildlife Park of Aiguamolls de l’Emporda` is estimated. The travel cost technique is applied to estimate the external value of the Park. According to the final results, the price of the reclaimed water in the Park should have to be between 0.75 ⁄/m3 (without opportunity cost) and 1.20 ⁄/m3(with opportunity cost). 2010-10-18T08:54:45Z http://hdl.handle.net/2117/7989 Title: Adaptación de biodigestores tubulares de plástico a climas fríos Authors: Poggio, Davide; Ferrer Martí, Ivet; Batet Miracle, Lluís; Velo García, Enrique Abstract: Farmers in the Andean Plateau strongly demand for household biodigesters due to the lack of clean fuels and agricultural fertilizers, and the abundance of livestock residues. The diffusion of rural biodigesters in cold climate or mountainous rural zones has been traditionally scarce. The unfavorable relationship between low temperatures and the kinetics of biogas production poses a technological barrier to the implementation of low cost biodigesters. Since 2006, the Research Group on Development Cooperation and Human Development (GRECDH) from the Technical University of Catalonia (UPC), in collaboration with the Peruvian NGO Institute for an Alternative Agriculture (IAA), investigates on the development of household biodigesters adapted to extreme conditions of the Andean Plateau (3000-4500 m). This article describes the research project and its main findings. 2010-07-02T14:11:48Z http://hdl.handle.net/2117/7853 Title: Sludge treatment wetlands: a review on the state of the art Authors: Uggetti, Enrica; Ferrer Martí, Ivet; Llorens Ribes, Esther; García Serrano, Joan Abstract: Sludge management has become a key issue in wastewater treatment, representing some 20–60% of the operational costs of conventional wastewater treatment plants. The high water content of the sludge results in large daily flow rates to be handled and treated. Thus, the search for methods to improve sludge volume reduction continues to be of major interest. The technology known as sludge treatment wetlands has been used for sludge dewatering since the late 1980s. Major advantages include its low energy requirements, reduced operating and maintenance costs, and a reasonable integration in the environment. However, the number of plants in operation is still low in comparison with conventional technologies. This study represents a review of the state of the art of sludge treatment wetlands. The main characteristics and operational aspects of the technology are described, including a summary of the main results reported in the literature. Finally, the efficiency of sludge treatment wetlands versus conventional treatments is compared. 2010-06-28T08:17:49Z http://hdl.handle.net/2117/7821 Title: Climate and CO2 saturation in an alpine lake throughout the Holocene Authors: Catalán, Jordi; Pla, S; García Serrano, Joan; Camarero, L Abstract: This study shows that diatom sediment records can be used to investigate the long-term inorganic carbon dynamics in oligotrophic and poorly acid-buffered lakes. Using a training set of 115 high-mountain lakes in the Pyrenees, we found that both alkalinity and potential hydrogen (pH) independently explained some of the variability in diatom assemblages. Transfer functions for both variables were developed and applied to a Holocene record from Lake Redon and CO2 changes calculated. CO2 saturation broadly followed alkalinity, which in turn was related to summer and autumn air-temperature fluctuations. In general, warmer climate during the ice-free period led to higher supersaturation, due to increased alkalinity, which facilitated retention of CO2 from respiration, and decreased primary production (assessed by diatom fluxes). Only during the early Holocene, there were periods of extreme undersaturation, corresponding to cold periods of low alkalinity (<20 microequivalents per liter [meq L21]), and suggesting carbon limitation of primary production. The winter and spring climate, which determines the ice cover duration, appears to be relevant for CO2 saturation only during periods when the organic-matter content of the sediments was low (,22%). Longer periods of ice cover led to lower lake CO2 saturation, suggesting that the ice cover influence on internal nutrient loading may regulate lake productivity fluctuations under low allocthonous nutrient and organic-matter inputs. Alkalinity ,20 meq L21 and sediment organic matter ,22% appear as critical thresholds in the way lake CO2 levels respond to climate fluctuations. 2010-06-23T17:34:21Z