Grupos Investigadores

Miembros del Grupo

Dalmau Martínez

Líneas de Investigación

  • Diseño y operación de tecnologías de tratamiento de aguas
  • Modelado matemático y simulación de sistemas de gestión y tratamiento del agua
  • Soluciones basadas en procesos químicos y físico-químicos en el tratamiento de aguas y residuos sólidos

Palabras Clave

  • Modelado matemático y simulación
  • Tratamiento y gestión de agua y residuos

Publicaciones Científicas desde 2018

  • Autores: Devos, P.; Filali, A.; Grau Gumbau, Paloma; et al.
    ISSN: 0043-1354 Vol.232 2023 págs. 119620 - *
    This review compiles information on sidestream characteristics that result from anaerobic digestion dewatering (conventional and preceded by a thermal hydrolysis process), biological and primary sludge thickening. The objective is to define a range of concentrations for the different characteristics found in literature and to confront them with the optimal operating conditions of sidestream processes for nutrient treatment or recovery. Each characteristic of sidestream (TSS, VSS, COD, N, P, Al3+, Ca2+, Cl-, Fe2+/3+, Mg2+, K+, Na+, SO42-, heavy metals, micro-pollutants and pathogens) is discussed according to the water resource recovery facility configuration, wastewater characteristics and implications for the recovery of nitrogen and phosphorus based on current published knowledge on the processes implemented at full-scale. The thorough analysis of sidestream characteristics shows that anaerobic digestion sidestreams have the highest ammonium content compared to biological and primary sludge sidestreams. Phosphate content in anaerobic digestion sidestreams depends on the type of applied phosphorus treatment but is also highly dependent on precipitation reactions within the digester. Thermal Hydrolysis Process (THP) mainly impacts COD, N and alkalinity content in anaerobic digestion sidestreams. Surprisingly, the concentration of phosphate is not higher compared to conventional anaerobic digestion, thus offering more attractive recovery possibilities upstream of the digester rather than in sidestreams. All sidestream processes investigated in the present study (struvite, partial nitrification/anammox, ammonia stripping, membranes, bioelectrochemical system, electrodialysis, ion exchange system and algae production) suffer from residual TSS in sidestreams. Above a certain threshold, residual COD and ions can also deteriorate the performance of the process or the purity of the final nutrient-based product. This article also provides a list of characteristics to measure to help in the choice of a specific process.
  • Autores: Aguilar-Pozo, V. B.; Chimenos, J. M.; Elduayen Echave, Beñat; et al.
    ISSN: 0048-9697 Vol.890 2023 págs. 164084
    Struvite precipitation is a well-known technology to recover and upcycle phosphorus from municipal wastewater as a slow-release fertiliser. However, the economic and environmental costs of struvite precipitation are constrained by using technical-grade reagents as a magnesium source. This research evaluates the feasibility of using a low-grade magnesium oxide (LG-MgO) by-product from the calcination of magnesite as a magnesium source to precipitate struvite from anaerobic digestion supernatants in wastewater treatment plants. Three distinct LG-MgOs were used in this research to capture the inherent variability of this by-product. The MgO content of the LG-MgOs varied from 42 % to 56 %, which governed the reactivity of the by-product. Experimental results showed that dosing LG-MgO at P:Mg molar ratio close to stoichiometry (i.e. 1:1 and 1:2) favoured struvite precipitation, whereas higher molar ratios (i.e. 1:4, 1:6 and 1:8) favoured calcium phosphate precipitation due to the higher calcium concentration and pH. At a P: Mg molar ratio of 1:1 and 1:2, the percentage of phosphate precipitated was 53-72 % and 89-97 %, respectively, depending on the LG-MgO reactivity. A final experiment was performed to examine the composition and morphology of the precipitate obtained under the most favourable conditions, which showed that (i) struvite was the mineral phase with the highest peaks intensity and (ii) struvite was present in two different shapes: hopper and polyhedral. Overall,
  • Autores: Lizarralde Aguirrezabal, Izaro (Autor de correspondencia); Guida, S.; Canellas, J.; et al.
    ISSN: 0043-1354 Vol.206 2021 págs. 117779
    Ammonia ion removal and recovery via an ion-exchange process using zeolites is a promising alternative to traditional biological treatments. The analysis of its efficiency is not straightforward as it depends on various factors, such as the cation exchange capacity of the zeolite, amount of zeolite available, initial ammonia concentration, contact time, ammonia speciation depending on pH or the presence of competing ions. Mathematical modelling and simulation tools are very useful to analyse the effect of different operational conditions on the efficiency and optimal operation of the process. This paper experimentally analyses the effect that the presence of competing ions has on the efficiency of ammonia removal. This experimental work has shown a reduction of around 21% of ammonia removal efficiency in the presence of competing ions. The main contribution of this paper is the development new mathematical model able to describe the ion-exchange process in the presence of competing ions. The mathematical model developed is able to analyse the performance of the IEX process under different empty bed contact times, influent loads, pH and concentrations of competing ions. The capability of the model to reproduce real data has been proven comparing the experimental and simulation results. Finally, an exploration by simulation has been undertaken to show the potential of the mathematical model developed.
  • Autores: Elduayen Echave, Beñat (Autor de correspondencia); Lizarralde Aguirrezabal, Izaro; Schneider, P.; et al.
    ISSN: 0043-1354 Vol.200 2021 págs. 117242
    The effect of mixing in the modelling of processes based on mass transfer phenomena is commonly ignored in wastewater treatment industry. In this contribution, the effect of the average shear rate in the nucleation and growth rates of struvite is analyzed by combining experimental data with simulation results obtained with a previously presented mass-based discretized population balance model. According to the obtained results, the effect of the average shear rate is identifiable for the selected data and mechanisms. Therefore, it should be considered when a detailed modelling of the process is needed. Consequently, in this contribution, the average shear rate has been decoupled from the kinetic constants. In addition, kinetic rates where it is explicitly included as a power law function have been proposed. The exponents in these power law functions for the primary homogeneous nucleation and growth are 1.3 and 0.3, respectively. Considering shear rate effects allowed to see in the simulation outputs experimentally observed effects: a faster pH decay and smaller particle distribution for increasing mixing intensities. (c) 2021 Elsevier Ltd. All rights reserved.
  • Autores: Elduayen Echave, Beñat (Autor de correspondencia); Azcona Calero, Mikel; Grau Gumbau, Paloma; et al.
    ISSN: 2214-7144 Vol.38 2020 págs. 101657
    Controlled struvite precipitation is a promising solution for phosphorus recovery in wastewater treatment plants. Particle size distribution of recovered struvite affects its efficacy as a fertilizer, so should be considered in the design and operation of struvite recovery reactors. This contribution analyzes the effect of varying the average shear rate (between 150 s(-1) and 876 s(-1)) and saturation index (between 0.76 and 2.96) in two different experimental set-ups. Solution pH and particle number and size measurements using an electric zone sensing method are used to monitor the process. In addition, photomicrographs are used to observe the shape of the precipitated particles. Interestingly, for identical thermochemical conditions, a higher mixing intensity, associated with the shear rate, leads to shorter induction times, faster precipitation and a greater particle density. On the other hand, for similar mixing conditions, a higher saturation index is also linked with shorter induction times, faster precipitation and a greater particle density. From the experimental data it is concluded that the effect of the fluid shear rate cannot be ignored and should be further studied in the precipitation process.

Proyectos desde 2018

  • Título: Modelado matemático y simulación de nuevos procesos y soluciones para la recuperación de fósforo de estaciones depuradoras de aguas residuales
    Código de expediente: PIBA_2022_1_0022
    Investigador principal: PALOMA GRAU GUMBAU, PALOMA GRAU GUMBAU.
    Convocatoria: Proyectos de Investigación Básica y/o Aplicada 2022-2024
    Fecha de inicio: 11-08-2022
    Fecha fin: 30-06-2025
    Importe concedido: 50.000,00€
    Otros fondos: -
  • Título: Modelado matemático y simulación de nuevos procesos y soluciones para la recuperación de fósforo de estaciones depuradoras de aguas residuales
    Código de expediente: PID2019-108378RB-I00
    Investigador principal: PALOMA GRAU GUMBAU.
    Convocatoria: 2019 AEI PROYECTOS I+D+i (incluye Generación del conocimiento y Retos investigación)
    Fecha de inicio: 01-06-2020
    Fecha fin: 31-05-2023
    Importe concedido: 102.850,00€
    Otros fondos: -