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[EN] The efficiency of nanofiltration to purify the tyrosol present in the olive mill wastewaters (OMWWs) has been studied. The similar molecular weight of tyrosol and the sucrose existing in this kind of by-products restricts the discrimination between both molecules through a membrane process, but the interest of phenolic compounds to be applied in cosmetics and pharmacology greatly motivates its recovery at the highest purity possible. Thus, two different simulated OMWWs composed of tyrosol and mixtures of tyrosol and sucrose, respectively, were nanofiltered using the NF270 membrane. Three transmembrane pressures (TMPs) and three cross-flow velocities were tested. The optimum results were obtained at 0.5 m.s(-1) and 15 bar. The rejections of the chemical oxygen demand (COD) were above 78 %, whereas phenolic compounds were barely retained. This indicates that the sugar was accurately separated from tyrosol, which was recovered in the permeate stream at a high purity., This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness through the project CTM201788645-R, and by the Spanish Ministry of Science, Innovation and Universities through the PRE2018-085245 pre-doctoral grant.

[EN] If we analyse some of the specific skills of Chemical Engineering degree, and it would not be very different in other disciplines of engineering, the verbs design, analyse or simulate stand out above all. In essence, calculating is an intrinsic activity for the engineer and, therefore, for engineering students. How is this activity developed? When we face a real problem we translate it into mathematical language (modelling). We solve the resulting mathematical problem to obtain the mathematical solution (simulation). The analysis of the results allows us to extract information from the real problem. If the interpretation of the results does not fit with the real problem studied, we must rethink the mathematical model obtained, and so on. Teachers often restrict the real problems that students face to simple situations so that the resulting mathematical problem is simple and, if possible, provides an analytical solution. Why should we do this today if we have numerical methods, a big computing power and mathematical software available to our students? Examples of complex mathematical problems arise from analysis and design of heat exchangers, chemical reactors, distillation columns, etc, both in steady and transitory regimes. These mathematical problems can be classified in groups: solving algebraic equations, ordinary differential equations or partial differential equations systems. According to this classification, some teachers of the Chemical Engineering degree at Campus of Alcoy are providing our students with Matlab guide templates to solve these types of mathematical problems, regardless of the subjects in which these problems appear. This action makes it easier for students to face real problems by reducing the mathematical difficulties associated. This paper shows how these Matlab guide templates are and how students use them in different subjects. It allows students to focus on the engineering aspect of the processes, leaving the difficulty of the associated mathematical problem in a second plane. It also makes easy to modify process parameters to quickly see the effect on the main variables of the process (what if? analysis). Consequently, students improve their ability to analyse and interpret the results obtained and their critical thinking skills. And, finally, they know useful computer tools that can be used both academically and professionally

[EN] An important issue in any academic degree is to develop a high level of vertical/horizontal coordination between the different subjects taught along the four courses. This activity takes into account the coordination of the contents and methodologies that the teachers teach and the students acquire, the timing when the students learn them and the homework/exams that they do. As a result, both teachers and students gain an overall view of the degree and the teaching-learning process improves. According to this idea, the teachers of the Chemical Engineering degree at Campus of Alcoy are participating in an Educational Innovation and Improvement Project (EIIP) for applying the project-based learning methodology to the design of an adsorption system for the elimination of dyes in wastewater from the textile industry. This work is scheduled along the four courses and is distributed between some of the basic or specialized subjects that the students attend. The adsorption column design is partially solved in each subject and the results obtained in one subject are used in the following. As a result, the project is completed sequentially throughout the degree applying a methodology based on teamwork. This paper shows some of the activities proposed in different subjects, their timing and assessments during four courses. These activities include laboratory work for obtaining adsorption equilibrium and adsorption kinetics experimental data together with column dynamic performance. Other activities belong to the modelling and simulation domain for establishing the mathematical equations corresponding to the different phenomena linked to adsorption. Also there are activities focused on experimental data treatment for estimating the parameters characterizing the adsorption isotherms or mass transfer coefficients. Finally, other activities are devoted to the column design and control, cost estimation, and oral/writing communication of the work done by the students., This article has been supported by Universitat Politècnica de València, particularly by the Vice-rectorate for Digital Resources and Documentation (Vicerrectorado de Recursos Digitales y Documentación) and Vice-Rectorate for Studies, Quality and Accreditation (Vicerrectorado de Estudios, Calidad y Acreditación) under the Call for Learning + Teaching (Convocatoria A+D2019: Aprendizaje + Docencia. Proyectos de Innovación y Mejora Educativa) and Project Code: A157. The authors would like to acknowledge the support of the Institute of Educational Sciences (Instituto de Ciencias de la Educación), the Evaluation and Monitoring Commission for Educational Innovation and Improvement Projects (Comisión de Evaluación y Seguimiento de Proyectos de Innovación y Mejora Educativa (CESPIME) and Escuela Politécnica Superior de Alcoy.

[EN] The production of olive oil generates wastewater with a high organic load and toxicity due to the high concentration of phenolic compounds. In recent years, the study on the treatments of these waters has been intensified together with the search for a process to recover these phenolic compounds due to their great antioxidant potential. All this with the aim of implementing the concept of circular economy. In this study, four different organic ultrafiltration membranes were evaluated in order to recover the phenolic compounds present in olive oil washing wastewater (OOWW) from an oil mill in the Valencian Community (Spain). The tested membranes differ in materials and molecular weight cut-off (MWCO): two permanently hydrophilic polyethersulfone (PESH) membranes with MWCO of 4 and 50 kDa, respectively, one polyethersulfone (PES) membrane with a MWCO of 5 kDa and a regenerated cellulose acetate (RCA) membrane with a MWCO of 10 kDa. Transmembrane pressure (TMP) and crossflow velocity (CFV) were varied from 1 to 3 bar and from 1.5 to 3.4 m/s, respectively. The effectiveness of the different membranes and operating conditions were evaluated comparing the permeate flux and the rejection of chemical oxygen demand (COD) and total phenolic compounds (TPhs). The membranes with lower MWCO showed stable permeate fluxes without significant changes over time, while the 50 kDa membrane showed a gradual decrease, without achieving a stable flux. Low rejection of phenolic compounds was observed in all cases, while the rejection of COD varied between 19.5 % and 62.9 % depending on the membrane and operating conditions tested. Except for the 50 kDa PESH membrane, initial permeability recovery greater than 95 % was achieved with a 35 °C water rinse, indicating that membrane fouling was not severe. Since the aim was to recover the TPhs in the permeate stream and separate them from the organic matter, the 5 kDa PES membrane at 2 bar and 2.5 m/s was considered to be the best option. At those conditions a stable permeate flux of 40 L/h·m2 was obtained, while the lowest TPhs rejection was observed (8.01 %) with a high COD rejection (61.18 %)., The authors acknowledge the financial support from the Spanish Ministry of Economy, Industry and Competitiveness through the project CTM2017-88645-R and The European Union through the Operational Program of the Social Fund (FSE).

[EN] Management of wastewater is a major challenge nowadays, due to increasing water demand, growing population and more stringent regulations on water quality. Wastewaters from food conservation are especially difficult to treat, since they have high salinity and high organic matter concentration. The aim of this work is the treatment of the effluent from a table olive fermentation process (FTOP) with the aim of reusing it once the organic matter is separated. The process proposed in this work consists of the following membrane-based technologies: Ultrafiltration (UF) (UP005, Microdyn Nadir), Forward Osmosis (FO) (Osmen2521, Hydration Technology Innovation) and Nanofiltration (NF) (NF245, Dow). The FO process was implemented to reduce the salinity entering the NF process, using the FTOP as draw solution and, at the same time, to concentrate the centrate produced in the sludge treatment of a municipal wastewater treatment plant with the aim of obtaining a stream enriched in nutrients. The UF step achieved the elimination of 50% of the chemical oxygen demand of the FTOP. The UF permeate was pumped to the FO system reducing the volume of the anaerobically digested sludge centrate (ADSC) by a factor of 3 in 6.5 h. Finally, the ultrafiltrated FTOP diluted by FO was subjected to NF. The transmembrane pressure needed in the NF stage was 40% lower than that required if the ultrafiltration permeate was directly nanofiltered. By means of the integrated process, the concentration of organic matter and phenolic compounds in the FTOP decreased by 97%. Therefore, the proposed process was able to obtain a treated brine that could be reused in other processes and simultaneously to concentrate a stream, such as the ADSC., This research was funded by CDTI (Centre for Industrial and Technological Development) depending on the Spanish Ministry of Science and Innovation through the INNPRONTA program, grant number IPT-20111020.

[EN] The membrane process of ultrafiltration (UF) has been investigated as a pretreatment previous to the further recovery and concentration of phenolic compounds from residual table olives fermentation brines. Two UF membranes were tested: a permanently hydrophilic polyethersulfone (PES) membrane with a molecular weight cut-off (MWCO) of 30 kDa and a PES membrane with a MWCO of 5 kDa. Transmembrane pressure and crossflow velocity were varied from 1 to 3 bar and from 2.2 to 3.7 m s(-1), respectively. The best membrane in terms of permeate flux and selectivity was that with MWCO of 5 kDa and the best operating conditions were transmembrane pressure of 3 bar and crossflow velocity of 2.2 m s(-1). In these conditions permeate flux was 21.6 L h(-1).m(-2), while the rejection of COD and phenolic compounds were 50.0% and 21.9%, respectively and the removal of colour and turbidity was almost complete. In addition, an alkaline cleaning protocol was proposed, which was effective to restore the initial permeability of the selected membrane. (C) 2018 Elsevier Ltd. All rights reserved., The authors of this work wish to gratefully acknowledge the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation (INNPRONTA program, ITP-20111020).

[EN] The ever-increasing occurrence and persistence of pharmaceutically active compounds (PhACs) in soils, sediments, drinking water supplies and wastewater effluents are a matter of serious environmental concern for governments and researchers worldwide. Nanofiltration as tertiary treatment method can be a viable and practical tool to remove these pollutants from aquatic environments. However, organic matter present in water sources can foul the membrane surface during operation, thus being potentially able to affect the membrane performance. Therefore, fouling mechanisms could heavily influence on the removal efficiencies. The purpose of this study was to investigate the implementation of three nano- filtration membranes (TFC-SR2, NF-270 and MPS-34) and to study both the rejection of trace PhACs and the fouling mechanisms for each membrane as a function of feed solution pH. Fouling mechanisms were predicted by Hermia's model adapted to cross-flow configurations. Results demonstrated that higher removals were obtained at slightly alkaline pH, especially for anionic trace PhACs. At the same conditions, more severe fouling was observed, which resulted in strong flux declines and an increase in hydrophobicity. This indicates that the attached organic matter on the membrane surface acts as a secondary selective barrier for separation., The authors thank the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P. Likewise, the authors also express their acknowledge to the personnel of the Carraixet WWTP for the kind supply of secondary effluent samples.

[EN] Nanofiltration (NF) membrane with low-pressure operating conditions and high flux permeability seems to be an attractive alternative for water softening and desalination. In order to study the performance of NF membrane on treating real brackish water, with mixture of mono and divalent ions, two commercial flat sheet nanofiltration membranes (NF90 and NP030) were used. The experiments were carried out with transmembrane pressure from 4 to 12 bar with three brackish waters having different ions concentrations. The results obtained showed that the high hydrophilicity of NF90 and its small pore size were the main advantages that allow this membrane to have the highest permeability and salt rejection for both mono and divalent ions in comparison with NP030. The results also showed that the permeate flux and rejection increased linearly with increasing in TMP. NF90 membrane performance was assessed by studying the effect of feed ions concentration. It was observed that the permeate flux decreased with increasing in salts concentration due to concentration polarization. Additionally, the study of scaling problem showed that its contribution in permeate flux decreasing was not as much significant and that the membrane permeability, recovered after the cleaning step, was 90%. In the other hand, the salts rejection of NF90 remained high (more than 80%) for all the studied concentrations due to its separation mechanism., This work was carried out with the support of scholarship awarded by the National Center for Scientific and Technical Research (CNRST) - Morocco.

[EN] The increasing demand on water resources throughout the world has motivated researchers to seek new ways to obtain quality water increasing their interest in water reclamation. However, the presence of harmful organic chemicals such as pharmaceutically active compounds (PhACs) is a serious environmental concern. The objective of this study was to investigate the influence of the pH on the rejection of seven target PhACs (acetaminophen, caffeine, erythromycin, ibuprofen, naproxen, sulfamethoxazole, and trimethoprim) by different low-pressure membranes within the fine ultrafiltration (UF) and loose nanofiltration (NF) range. For this purpose, three ceramic membranes and a polyamide membrane were used for UF and NF experiments, respectively. Experimental results indicated that PhACs with negative charge were effectively rejected at basic conditions (< 75% for UF, < 90% for NF), improving both their hydrophilicity and solubility with increasing pH. Furthermore, high soluble PhACs with high pKa values showed low rejection values (similar to 15% for UF, similar to 30% for NF) and a pH-independent behaviour during low-pressure filtration experiments. Therefore, the use of low-pressure membranes could be considered as an appropriate and sustainable supplemental technique to remove PhACs in a wastewater treatment plant., The authors of this work wish to gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P.

[EN] In this work, the fouling mechanisms that dominate the ultrafiltration of residual brines from table olive packing plant wastewaters were investigated. For that purpose, Hermia's models adapted to crossflow filtration, resistance-in-series model and a model combining intermediate blocking and cake formation mechanisms were fitted to the experimental data. Tests were performed with a 5 kDa polyethersulfone membrane at transmembrane pressures between 1 and 3 bar and crossflow velocities between 2.2 and 3.7 m s(-1). Results demonstrated that the resistance-in-series model was the most accurate to predict permeate flux evolution with time. The predominant fouling mechanism was cake formation followed by intermediate blocking/adsorption. The fouling resistances that were determined by means of the resistance in series model were tested using a well-established mathematical model proposed by Mondal and De that also combines both fouling phenomena (intermediate pore blocking and cake formation). Results demonstrated that the predicted resistances are consistent with those determined by Mondal and De's model. (C) 2016 Elsevier Ltd. All rights reserved., The authors of this work wish to gratefully acknowledge the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation (INNPRONTA program, ITP-20111020).

[EN] The fermentation brines from table olive processing (FTOP) are hypersaline effluents (conductivities higher than 75 mS·cm-1) with high organic matter concentrations (COD around 10 g·L-1), which also include phenolic compounds (between 700 and 1500 mg TY·L-1). In this work, an integrated process for the FTOP reuse as brine in the table olive processing has been evaluated. This integrated process consisted of a biological treatment followed by a membrane system, which included ultrafiltration (UF) plus nanofiltration (NF). The biological treatment was carried out by 6 L laboratory sequencing batch reactor (SBR). UF and NF were performed in laboratory plants for flat membranes of 0.0125 and 0.0072 m2, respectively. Each stream generated during the FTOP treatment (SBR effluent, and UF and NF permeates) were evaluated. The SBR eliminated around 80% of COD and 71% of total phenols concentration. In the final NF permeate the COD concentration was lower than 125 mg·L-1; while the turbidity, colour and phenolic compounds, were completely removed., The authors of this work thank the financial support of CDTI (Centre for Development Technological Industrial) depending on the Spanish Ministry of Science and Innovation.

[EN] This study investigates the influence of feed solution pH and fouling on the rejection of ten selected pharmaceutically active compounds (PhACs) with different physicochemical characteristics (molecular weight, water solubility, log Kow, pKa, dipole moment, etc.) by three multichannel ceramic ultrafiltration membranes, ranging from 1 to 8 kDa, in order to improve their removal from water. For this purpose, the comparison between filtration of PhACs in deionised water (Feed I) and in real wastewater effluent (Feed II) was performed, demonstrating that the variation of pH and the formation of a foulant layer altered the separation mechanism and hence the rejection values of each PhAC varied. Higher rejections of most of the PhACs were higher at slightly alkaline pH, especially for anionic compounds in the filtration with real wastewater. In these conditions, flux decline was more severe. The formed fouling layer onto the hydrophilic membrane surface acted as a secondary barrier for separation with different properties like hydrophobicity and charge. Electrostatic interactions were the main separation mechanism in the filtration of PhACs in deionised water, while the hydrophobic/hydrophilic interactions played a crucial role in the filtration experiments with real wastewater effluent. Thus, the reported results indicated that the rejection of pharmaceutically active compounds was strongly pH-dependent, except for hydrophilic neutral compounds (acetaminophen and caffeine), which showed a pH-independent behaviour with low rejection values. (C) 2016 Elsevier B.V. All rights reserved., The authors of this work wish to gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P.

[EN] This work studies the adequacy of different reverse osmosis (RO) pretreatments applied to different petrochemical wastewater effluents. Three effluents from a caprolactam factory were analysed: ion-exchange resin washing effluent (RWE), batch reactor washing effluent and factory outlet effluent. Coagulation–flocculation, microfiltration (MF) and ultrafiltration (UF) were tested as RO pretreatments. Various inorganic coagulants (Aluminium Chloride, Iron (III) Chloride, Aluminium Sulphate and polyaluminium chloride), commercial coagulants (Nophos and ACO) and commercial flocculants (polyacrylamide, CH-30 and active polyfloc) were tested at different dosages and stirring speeds. The highest removal of suspended solids (SS) and the lowest turbidity were obtained for the ion-exchange RWE. Two combinations of coagulants and flocculants were chosen as the most suitable conditions for the coagulation–flocculation process. The ion-exchange RWE was further treated with a combination of MF followed by UF. SS were completely removed and turbidity decreased to 0.136 NTU. The silt density index at 15 min was reduced to 6.41., The authors of this work wish to gratefully acknowledge the financial support from the Generalitat Valenciana through the programme “Ayudas para la realizacio´n de proyectos I+D para grupos de investigacio´n emergentes GV/2013”.