DSpace Comunidad:http://hdl.handle.net/10045/294652019-04-26T01:24:34Z2019-04-26T01:24:34ZOptimization of multistage membrane distillation system for treating shale gas produced waterCarrero-Parreño, AlbaOnishi, Viviani C.Ruiz-Femenia, RubénSalcedo Díaz, RaquelCaballero, José A.Reyes-Labarta, Juan A.http://hdl.handle.net/10045/901492019-03-26T01:10:57Z2019-06-15T00:00:00ZTítulo: Optimization of multistage membrane distillation system for treating shale gas produced water
Autor/es: Carrero-Parreño, Alba; Onishi, Viviani C.; Ruiz-Femenia, Rubén; Salcedo Díaz, Raquel; Caballero, José A.; Reyes-Labarta, Juan A.
Resumen: Thermal membrane distillation (MD) is an emerging technology to desalinate high-salinity wastewaters, including shale gas produced water to reduce the corresponding water footprint of fracturing operations. In this work, we introduce a rigorous optimization model with energy recovery for the synthesis of multistage direct contact membrane distillation (DCMD) system. The mathematical model (implemented in GAMS software) is formulated via generalized disjunctive programming (GDP) and mixed-integer nonlinear programming (MINLP). To maximize the total amount of water recovered, the outflow brine is fixed close to salt saturation conditions (300 g·kg−1 water) approaching zero liquid discharge (ZLD). A sensitivity analysis is performed to evaluate the system's behavior under different uncertainty sources such as the heat source availability and inlet salinity conditions. The results emphasize the applicability of this promising technology, especially with low steam cost or waste heat, and reveal variable costs and system configurations depending on inlet conditions. For a produced water salinity ranging from 150 g·kg−1 water to 250 g·kg−1 water based on Marcellus play, an optimal treating cost are between 11.5 and 4.4 US$ m−3 is obtained when using low-cost steam. This cost can decrease to 2.8 US$ m−3 when waste heat from shale gas operations is used.2019-06-15T00:00:00ZKaibel column: Modeling, optimization, and conceptual design of multi-product dividing wall columnsRawlings, E. SorayaChen, QiGrossmann, Ignacio E.Caballero, José A.http://hdl.handle.net/10045/899082019-03-21T01:03:52Z2019-06-09T00:00:00ZTítulo: Kaibel column: Modeling, optimization, and conceptual design of multi-product dividing wall columns
Autor/es: Rawlings, E. Soraya; Chen, Qi; Grossmann, Ignacio E.; Caballero, José A.
Resumen: In this work, we present the modeling, optimization, and conceptual design of a dividing wall column for the separation of four products, commonly referred to in the literature as a Kaibel column, by implementing three different formulations: an NLP, an MINLP, and a GDP formulation. For its solution, we propose a rigorous tray-by-tray model and compared it to results from a commercial software, followed by its reformulation to include a mixed-integer nonlinear programming and a general disjunctive programming formulation to respond to the conceptual design problem attached to these complex configurations. Considering the proposed rigorous model and the two formulations, the Kaibel column is solved, obtaining four high-purity products and new optimal tray locations for the feed and two side product streams, when the mixed-integer nonlinear programming formulation is applied. The use of these optimally located side streams showed reductions in the energy consumption when compared to cases were non-optimal fixed tray locations are used. When the general disjunctive programming problem was solved, the minimum number of trays needed in the main column and dividing wall are obtained, showing a great reduction of the remixing effects in the Kaibel column, and with that, a more energy efficient configuration. The models were coded in Pyomo using the solver IPOPT for the solution of the nonlinear programming problem, the solver Bonmin for the solution of the mixed-integer nonlinear programming problem, and GDPopt for the solution of the general disjunctive programming optimization problem.2019-06-09T00:00:00ZMinimizing the total annualized cost of “SIDEM” seawater desalination unitBen Hamad, MahaRuiz-Femenia, RubénSnoussi, AliBen Brahim, AmmarCaballero, José A.http://hdl.handle.net/10045/893472019-03-09T01:03:58Z2018-05-01T00:00:00ZTítulo: Minimizing the total annualized cost of “SIDEM” seawater desalination unit
Autor/es: Ben Hamad, Maha; Ruiz-Femenia, Rubén; Snoussi, Ali; Ben Brahim, Ammar; Caballero, José A.
Resumen: This paper presents a steady state analysis of a multi-effect thermal vapor compression desalination plant (MED-TVC) installed in the Tunisian Chemical Group (GCT) factory. A thermodynamic model includes mass and energy balances of the system are presented. An economic model is developed to estimate the cost of produced water ($/m3). The proposed models to minimize the total annualized cost (TAC) of the desalination unit are based on a combination between the process simulator Aspen HYSYS and Matlab. The effects of the operating parameters variations on the system’s performance were studied. The simulation results show a good agreement with the industrial data of the pilot unit.2018-05-01T00:00:00ZEffective catalytic removal of nitrates from drinking water: An unresolved problem?Ruiz Beviá, FranciscoFernandez-Torres, Maria J.http://hdl.handle.net/10045/876602019-02-06T01:05:08Z2019-04-20T00:00:00ZTítulo: Effective catalytic removal of nitrates from drinking water: An unresolved problem?
Autor/es: Ruiz Beviá, Francisco; Fernandez-Torres, Maria J.
Resumen: Over the past 29 years there have been myriad research efforts into the catalytic removal of nitrates from drinking water. In this work, 147 papers published during that period have been examined from the point of view of the ability of catalysis to produce water that is suitable for human consumption as well as amenable to industrial scale-up at reasonable working conditions of temperature and residence time. After close examination of the aforementioned articles, it is evident that this methodology has fulfilled only half its aims: it is able to reduce the nitrate concentration to guideline levels for human consumption, but it inevitably produces concentrations of ammonia and nitrites that are beyond the accepted limits for safe consumption of water. It is sometimes recommended that catalysis be combined with an ancillary technique, such as adsorption, in order to eliminate the undesirable byproducts mentioned above. However, this implies resorting to extra treatment units at the industrial scale, thus making the whole treatment process more complex and expensive. Our conclusion is that the effective catalytic removal of nitrates from drinking water is a very difficult problem.2019-04-20T00:00:00Z