Design and optimization of a resin technology system for the elimination of oil from industrial wastewater
- Autores: Maria dels Àngels Tejero Iborra
- Directores de la Tesis: Ricard Garcia Valls (dir. tes.), Verónica Gómez Cortés (codir. tes.)
- Lectura: En la Universitat Rovira i Virgili ( España ) en 2020
- Idioma: español
- Tribunal Calificador de la Tesis: Wojciech Kujawski (presid.), Josep Font Capafons (secret.), Martin Deetz (voc.)
- Programa de doctorado: Programa de Doctorado en Nanociencia, Materiales e Ingeniería Química por la Universidad Rovira i Virgili
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
Oily wastewater is ubiquitous in the industrial sector, especially refineries and the petrochemical industry. It poses a huge environmental problem because it includes a broad range of organic compounds that represent a grave threat both to aquatic ecosystems and to human health. Therefore, these waters must be treated for discharge, and must comply with the regulatory limits established by the EU. It is also necessary to treat them for the purpose of reuse, due to the fact that hydrocarbons can have a great impact on other downstream technologies such as reverse osmosis. The conventional approach for oily wastewater treatment can struggle to deal with this challenging wastewater in an environmentally acceptable manner. Oily waters may contain between 1 and 3% of hydrocarbons up to after treatment with conventional technologies. This oil will be present mainly as suspended microscopic droplets and a dissolved fraction of organic compounds. This PhD research project has aimed to explore the remediation of oily wastewater through the use of resin technology, with the ultimate goal of being able to design a functional system for the treatment of industrial wastewater. The main objectives of this project has been the design, validation and optimization of a system for the treatment of industrial wastewater integrating different types of polymeric resins, mainly coalescence and adsorption resins, with the purpose of removing oil and grease from water. This project has first focused on the systematic characterization of oily process wastewater, in order to gain a deeper understanding of oily waters and the potential needs of an oil removal system. This has led to the identification of key components that are present in all forms of oily wastewater originating from fossil fuels. It has been found that in spite of their immense variability, most differences are in the relative composition of the oil fraction and the presence of process additives. This has led to the identification of appropriate methods for routine quantitative analysis of components of oil water that are expected to be present in most types of oily water. This process has also fully characterized different types of resins for the purposes of system design. In particular two resins have been studied, each of them aimed to target the two problematic fractions of oil found in oily wastewater. An oleophilic resin has been studied for the removal of emulsified oil through a coalescence process, and a polymeric adsorbent has been studied for the purpose of removal of oil through adsorption mechanisms. A fundamental study of the impact of operational variables and wastewater chemical composition on both coalescer and adsorption systems has been performed in a bench-scale experimental set-up in order to determine the operational limits or oil-removal resins. A study has been made of the operation of a coalescer-type unit under different operating conditions that have been shown to have an effect on overall coalescer efficiency. These efforts have allowed us to determine the critical variables for coalescer performance, and to develop a basic predictive model that provides a conservative estimate of performance, as well as design guidelines for this type of system. Similarly, there has been a study on the differential adsorption of common oily-water dissolved components by adsorbent resin media. The isotherms of different components show that there are important differences in the affinity of the adsorbent for the different typical components of oily water, which have important implications in the behavior and recovery of spent adsorbents. Pilot-scale testing has been used to develop further the concept of oil removal through resin technology and aiding in optimization and troubleshooting of the process. Piloting has allowed a determination of the efficiency of the regeneration process, and the effect of changing wastewater composition on resin loading cycles, resin recovery and fouling. Using the operational and analytical resources developed in the course of this thesis, it has been possible to carry out an evaluation of the suitability of resin technology for the treatment of a certain types of oily wastewater. The tangible results of this thesis include a set of guidelines for the applications of resins to oil-removal applications.
Postgraduate and Doctorate School - URV | (+34) 977256596 / 977558478 - tesis@urv.cat
