Enrique Ferrero - Academia.edu (original) (raw)
Papers by Enrique Ferrero
In desalination plants, disinfection is necessary to control biofouling, one of the main problems... more In desalination plants, disinfection is necessary to control biofouling, one of the main problems in the long-term performance of reverse osmosis membranes. The addition of both chlorine and the dechlorination reagents affects oxidation and reduction potential (ORP). The present investigation evaluates the evolution with time between bisulfite dose and ORP values, to assess the impact of chlorine dioxide, chlorite, chlorate and dissolved metals in the redox potential. Results showed that using chlorine dioxide as an oxidant (1 mg/L), it was needed at least 45.8 mg/L of bisulfite to reduce ORP values below 300 mV. In the presence of chlorite ion (0.65 mg/L) and adding 100 µg/L of different dissolved metals, the redox potential values did not increase higher than 300 mV except for cobalt (Co 2+); at 3 mg/L of chlorite, it was needed at least 46.9 mg/L of bisulfite to reduce the ORP below 300 mV. The influence of bisulfite without chlorination species in brackish water, but with dissolved metals showed redox values always below 300 mV, except for 15 mg/L of bisulfite with 250 and 500 µg/L of dissolved Co 2+. Overall, the presence of chlorine dioxide, chlorite and dissolved metals, particularly Co 2+ , has a strong influence on the behavior of the redox potential after the addition of bisulfite.
Journal of Polymer Science Part A, Sep 19, 2002
A series of polyisophthalamides containing pendent phthalimido groups and flexible side spacers w... more A series of polyisophthalamides containing pendent phthalimido groups and flexible side spacers were prepared from four novel diacids and three commercial aromatic diamines. These polyamides were prepared in high yields and with high molecular weights by direct polycondensation with triphenyl phosphite and pyridine as condensing agents. The weight-average and number-average molecular weights, measured by gel permeation chromatography, were 70,000-137,000 and 47,000-86,000 g/mol, respectively. The novel polyamides were amorphous and readily soluble and showed glass-transition temperatures of 150-240°C, as measured by differential scanning calorimetry. Thermogravimetric analysis showed that the 10% weight-loss temperatures in nitrogen were 355-430°C, a significant improvement in thermal stability having been observed with the increase in the side-chain length. A theoretical quantum mechanical study was successfully carried out to explain these results. Flexible and tough films, cast from polymer solutions, showed tensile strengths of 50-125 MPa.
Chemical Engineering Journal, Oct 1, 2017
An intensive evaluation of draw solutions (DS) was performed by focusing on the wastewater reuse ... more An intensive evaluation of draw solutions (DS) was performed by focusing on the wastewater reuse applications of hybrid forward osmosis (FO) processes. The substances studied were potassium formate, potassium phosphate, magnesium sulphate, sodium chloride, sodium polyacrylate and polyethylene glycol, and their osmotic pressure, conductivity, pH, thermostability, sunlight exposure, toxicity, FO filtration performance and replenishment costs were determined. Additionally, commercially available FO membrane modules were evaluated at pilot scale. The results revealed that the most relevant DS properties for wastewater reuse under the studied conditions were the DS regeneration method, DS replacement price, pH adjustment and toxicity. These properties were shown to be more relevant than filtration flux when a maximum DS osmotic pressure value of 10 bar was used. This was the limit for efficient DS recovery. When the different FO membranes were compared, thin-film composite (TFC) flat-*Revised Manuscript (clean for typesetting) Click here to view linked References 2 sheet membranes showed the highest flux and the highest salt rejection, and the lowest permeability and salt rejection values were presented by cellulose triacetate (CTA) hollow fibre membranes. Based on the information obtained, a TFC-FO/nanofiltration (NF) demonstration plant will be constructed next to the wastewater treatment plant (WWTP) in San Pedro del Pinatar, in the region of Murcia (Spain). This represents the world's first FO demonstration plant for municipal wastewater reclamation and its results will allow this technology to be evaluated for wastewater reuse for agricultural purposes.
Retema: Revista técnica de medio ambiente, 2012
Journal of Polymer Science Part A, Feb 15, 2001
Desalination and Water Treatment, Jun 25, 2012
Incrustations reduce the yield in desalination methods: they reduce the productivity, increase th... more Incrustations reduce the yield in desalination methods: they reduce the productivity, increase the costs, and generate poor-quality water. The kinetics of the formation of incrustations when anti-incruster agents are introduced into the system is not easily comprehensible and the prediction may be frequently erroneous if the anti-incruster agent is not analysed in the correct manner. The invention relates to a method for evaluating anti-incruster agents, comprising the following steps: a) preparation of substitute ocean water (SOW) with a concentration of between 1 and 10; b) addition of the anti-incruster agent to be evaluated; and c) measurement of the turbidity over time.
El presente trabajo describe el desarrollo de un metodo de laboratorio que permite comparar el ef... more El presente trabajo describe el desarrollo de un metodo de laboratorio que permite comparar el efecto inhibitorio en la precipitacion del sulfato calcico con distintos antiincrustantes (AC). Para ello. se preparo una disolucion con una concentracion de sales superior al agua de mar. pero manteniendo las relaciones' de concentraciones existentes en ella. De este modo. se sobresatura la disolucion provocando la precipitacion de sales. La medida de tiempos de induccion permite analizar el efecto que provocan los distintos AC en la precipitacion.
ABSTRACT El presente trabajo describe el desarrollo de un método de laboratorio que permite compa... more ABSTRACT El presente trabajo describe el desarrollo de un método de laboratorio que permite comparar el efecto inhibitorio en la precipitación del sulfato de calcio de distintos anti-incrustantes. Para ello se preparó una disolución con una concentración de sales superior a la del agua de mar; pero manteniendo las relaciones de concentraciónes existentes en ella. De este modo, se sobresatura la disolución provocando la precipitación. La medida de tiempos de inducción permite analizar el efecto que provocan los distintos anti-incrustantes en la precipitación.
DESALINATION AND WATER TREATMENT
In desalination plants, disinfection is necessary to control biofouling, one of the main problems... more In desalination plants, disinfection is necessary to control biofouling, one of the main problems in the long-term performance of reverse osmosis membranes. The addition of both chlorine and the dechlorination reagents affects oxidation and reduction potential (ORP). The present investigation evaluates the evolution with time between bisulfite dose and ORP values, to assess the impact of chlorine dioxide, chlorite, chlorate and dissolved metals in the redox potential. Results showed that using chlorine dioxide as an oxidant (1 mg/L), it was needed at least 45.8 mg/L of bisulfite to reduce ORP values below 300 mV. In the presence of chlorite ion (0.65 mg/L) and adding 100 µg/L of different dissolved metals, the redox potential values did not increase higher than 300 mV except for cobalt (Co 2+); at 3 mg/L of chlorite, it was needed at least 46.9 mg/L of bisulfite to reduce the ORP below 300 mV. The influence of bisulfite without chlorination species in brackish water, but with dissolved metals showed redox values always below 300 mV, except for 15 mg/L of bisulfite with 250 and 500 µg/L of dissolved Co 2+. Overall, the presence of chlorine dioxide, chlorite and dissolved metals, particularly Co 2+ , has a strong influence on the behavior of the redox potential after the addition of bisulfite.
International Journal of Computational Methods and Experimental Measurements
Dissolved air flotation (DAF) technologies are commonly used in water and wastewater treatment. I... more Dissolved air flotation (DAF) technologies are commonly used in water and wastewater treatment. In particular, flotation of suspended solids to pre-treat high salinity water such as seawater is now becoming more widespread, even though conductivity effects on microbubble formation and behaviour are not yet well known. Thus, a series of experiments were conducted with artificial sea water and distilled water to study the effects of conductivity on size and flow patterns of the air bubbles inside a pilotscale DAF tank. The experimental setup included a high-speed CCD camera to capture the generated microbubbles. Posterior image processing determined the bubble diameters. Also, fluorescein was used as a fluorescent tracer to follow flow paths. The viability of using fluorescein was first assessed at laboratory scale. The intensity of the dye was determined through molecular fluorescence as a function of the concentration using a high conductivity matrix. Furthermore, a stability study of the intensity along time was performed in order to ensure reliability of the experimental measurements. The results showed that bubble size decreased and dead areas increased when seawater was used instead of distilled water.
DESALINATION AND WATER TREATMENT
Journal of Water Process Engineering
Chemical Engineering Journal
Chemosphere, 2017
In this study, bench scale dissolved air flotation (DAF) and settling processes have been studied... more In this study, bench scale dissolved air flotation (DAF) and settling processes have been studied and compared to a novel flotation technology based on the use of glass microspheres of limited buoyancy and its combination with conventional DAF, (Enhanced DAF or E-DAF). They were evaluated as pretreatments for advanced oxidation processes (AOPs) to polish produced water (PW) for reuse purposes. Settling and E-DAF without air injection showed adequate turbidity and oil and grease (O&G) removals, with eliminations higher than 87% and 90% respectively, employing 70 mg L(-1) of FeCl3 and 83 min of settling time, and 57.9 mg L(-1) of FeCl3, 300 mg L(-1) of microspheres and a flocculation rate of 40 rpm in the E-DAF process. A linear correlation was observed between final O&G concentration and turbidity after E-DAF. In order to polish the O&G content of the effluent even further, to remove soluble compounds as phenol and to take advantage of residual iron after these treatments, Fenton and...
One of the most significant factors for a good performance and cost effectively operating a rever... more One of the most significant factors for a good performance and cost effectively operating a reverse osmosis desalination plant is the capacity of the pre-treatment to consistently produce high quality feed water. The use of low pressure filtration membranes pre-treatment become important in the last years because of the potential benefits compared with conventional, in terms of improved water quality, fewer RO cleanings and lower pressure drops. In the present work, different commercial NF membranes have been hydraulically characterized with synthetic seawater and analysed with FTIR-ATR, SEM, AFM and streaming potential. The results give us an evaluation of each membrane for their potential use as pretreatment for a RO desalination plant.
Retema Revista Tecnica De Medio Ambiente, 2012
In desalination plants, disinfection is necessary to control biofouling, one of the main problems... more In desalination plants, disinfection is necessary to control biofouling, one of the main problems in the long-term performance of reverse osmosis membranes. The addition of both chlorine and the dechlorination reagents affects oxidation and reduction potential (ORP). The present investigation evaluates the evolution with time between bisulfite dose and ORP values, to assess the impact of chlorine dioxide, chlorite, chlorate and dissolved metals in the redox potential. Results showed that using chlorine dioxide as an oxidant (1 mg/L), it was needed at least 45.8 mg/L of bisulfite to reduce ORP values below 300 mV. In the presence of chlorite ion (0.65 mg/L) and adding 100 µg/L of different dissolved metals, the redox potential values did not increase higher than 300 mV except for cobalt (Co 2+); at 3 mg/L of chlorite, it was needed at least 46.9 mg/L of bisulfite to reduce the ORP below 300 mV. The influence of bisulfite without chlorination species in brackish water, but with dissolved metals showed redox values always below 300 mV, except for 15 mg/L of bisulfite with 250 and 500 µg/L of dissolved Co 2+. Overall, the presence of chlorine dioxide, chlorite and dissolved metals, particularly Co 2+ , has a strong influence on the behavior of the redox potential after the addition of bisulfite.
Journal of Polymer Science Part A, Sep 19, 2002
A series of polyisophthalamides containing pendent phthalimido groups and flexible side spacers w... more A series of polyisophthalamides containing pendent phthalimido groups and flexible side spacers were prepared from four novel diacids and three commercial aromatic diamines. These polyamides were prepared in high yields and with high molecular weights by direct polycondensation with triphenyl phosphite and pyridine as condensing agents. The weight-average and number-average molecular weights, measured by gel permeation chromatography, were 70,000-137,000 and 47,000-86,000 g/mol, respectively. The novel polyamides were amorphous and readily soluble and showed glass-transition temperatures of 150-240°C, as measured by differential scanning calorimetry. Thermogravimetric analysis showed that the 10% weight-loss temperatures in nitrogen were 355-430°C, a significant improvement in thermal stability having been observed with the increase in the side-chain length. A theoretical quantum mechanical study was successfully carried out to explain these results. Flexible and tough films, cast from polymer solutions, showed tensile strengths of 50-125 MPa.
Chemical Engineering Journal, Oct 1, 2017
An intensive evaluation of draw solutions (DS) was performed by focusing on the wastewater reuse ... more An intensive evaluation of draw solutions (DS) was performed by focusing on the wastewater reuse applications of hybrid forward osmosis (FO) processes. The substances studied were potassium formate, potassium phosphate, magnesium sulphate, sodium chloride, sodium polyacrylate and polyethylene glycol, and their osmotic pressure, conductivity, pH, thermostability, sunlight exposure, toxicity, FO filtration performance and replenishment costs were determined. Additionally, commercially available FO membrane modules were evaluated at pilot scale. The results revealed that the most relevant DS properties for wastewater reuse under the studied conditions were the DS regeneration method, DS replacement price, pH adjustment and toxicity. These properties were shown to be more relevant than filtration flux when a maximum DS osmotic pressure value of 10 bar was used. This was the limit for efficient DS recovery. When the different FO membranes were compared, thin-film composite (TFC) flat-*Revised Manuscript (clean for typesetting) Click here to view linked References 2 sheet membranes showed the highest flux and the highest salt rejection, and the lowest permeability and salt rejection values were presented by cellulose triacetate (CTA) hollow fibre membranes. Based on the information obtained, a TFC-FO/nanofiltration (NF) demonstration plant will be constructed next to the wastewater treatment plant (WWTP) in San Pedro del Pinatar, in the region of Murcia (Spain). This represents the world's first FO demonstration plant for municipal wastewater reclamation and its results will allow this technology to be evaluated for wastewater reuse for agricultural purposes.
Retema: Revista técnica de medio ambiente, 2012
Journal of Polymer Science Part A, Feb 15, 2001
Desalination and Water Treatment, Jun 25, 2012
Incrustations reduce the yield in desalination methods: they reduce the productivity, increase th... more Incrustations reduce the yield in desalination methods: they reduce the productivity, increase the costs, and generate poor-quality water. The kinetics of the formation of incrustations when anti-incruster agents are introduced into the system is not easily comprehensible and the prediction may be frequently erroneous if the anti-incruster agent is not analysed in the correct manner. The invention relates to a method for evaluating anti-incruster agents, comprising the following steps: a) preparation of substitute ocean water (SOW) with a concentration of between 1 and 10; b) addition of the anti-incruster agent to be evaluated; and c) measurement of the turbidity over time.
El presente trabajo describe el desarrollo de un metodo de laboratorio que permite comparar el ef... more El presente trabajo describe el desarrollo de un metodo de laboratorio que permite comparar el efecto inhibitorio en la precipitacion del sulfato calcico con distintos antiincrustantes (AC). Para ello. se preparo una disolucion con una concentracion de sales superior al agua de mar. pero manteniendo las relaciones' de concentraciones existentes en ella. De este modo. se sobresatura la disolucion provocando la precipitacion de sales. La medida de tiempos de induccion permite analizar el efecto que provocan los distintos AC en la precipitacion.
ABSTRACT El presente trabajo describe el desarrollo de un método de laboratorio que permite compa... more ABSTRACT El presente trabajo describe el desarrollo de un método de laboratorio que permite comparar el efecto inhibitorio en la precipitación del sulfato de calcio de distintos anti-incrustantes. Para ello se preparó una disolución con una concentración de sales superior a la del agua de mar; pero manteniendo las relaciones de concentraciónes existentes en ella. De este modo, se sobresatura la disolución provocando la precipitación. La medida de tiempos de inducción permite analizar el efecto que provocan los distintos anti-incrustantes en la precipitación.
DESALINATION AND WATER TREATMENT
In desalination plants, disinfection is necessary to control biofouling, one of the main problems... more In desalination plants, disinfection is necessary to control biofouling, one of the main problems in the long-term performance of reverse osmosis membranes. The addition of both chlorine and the dechlorination reagents affects oxidation and reduction potential (ORP). The present investigation evaluates the evolution with time between bisulfite dose and ORP values, to assess the impact of chlorine dioxide, chlorite, chlorate and dissolved metals in the redox potential. Results showed that using chlorine dioxide as an oxidant (1 mg/L), it was needed at least 45.8 mg/L of bisulfite to reduce ORP values below 300 mV. In the presence of chlorite ion (0.65 mg/L) and adding 100 µg/L of different dissolved metals, the redox potential values did not increase higher than 300 mV except for cobalt (Co 2+); at 3 mg/L of chlorite, it was needed at least 46.9 mg/L of bisulfite to reduce the ORP below 300 mV. The influence of bisulfite without chlorination species in brackish water, but with dissolved metals showed redox values always below 300 mV, except for 15 mg/L of bisulfite with 250 and 500 µg/L of dissolved Co 2+. Overall, the presence of chlorine dioxide, chlorite and dissolved metals, particularly Co 2+ , has a strong influence on the behavior of the redox potential after the addition of bisulfite.
International Journal of Computational Methods and Experimental Measurements
Dissolved air flotation (DAF) technologies are commonly used in water and wastewater treatment. I... more Dissolved air flotation (DAF) technologies are commonly used in water and wastewater treatment. In particular, flotation of suspended solids to pre-treat high salinity water such as seawater is now becoming more widespread, even though conductivity effects on microbubble formation and behaviour are not yet well known. Thus, a series of experiments were conducted with artificial sea water and distilled water to study the effects of conductivity on size and flow patterns of the air bubbles inside a pilotscale DAF tank. The experimental setup included a high-speed CCD camera to capture the generated microbubbles. Posterior image processing determined the bubble diameters. Also, fluorescein was used as a fluorescent tracer to follow flow paths. The viability of using fluorescein was first assessed at laboratory scale. The intensity of the dye was determined through molecular fluorescence as a function of the concentration using a high conductivity matrix. Furthermore, a stability study of the intensity along time was performed in order to ensure reliability of the experimental measurements. The results showed that bubble size decreased and dead areas increased when seawater was used instead of distilled water.
DESALINATION AND WATER TREATMENT
Journal of Water Process Engineering
Chemical Engineering Journal
Chemosphere, 2017
In this study, bench scale dissolved air flotation (DAF) and settling processes have been studied... more In this study, bench scale dissolved air flotation (DAF) and settling processes have been studied and compared to a novel flotation technology based on the use of glass microspheres of limited buoyancy and its combination with conventional DAF, (Enhanced DAF or E-DAF). They were evaluated as pretreatments for advanced oxidation processes (AOPs) to polish produced water (PW) for reuse purposes. Settling and E-DAF without air injection showed adequate turbidity and oil and grease (O&G) removals, with eliminations higher than 87% and 90% respectively, employing 70 mg L(-1) of FeCl3 and 83 min of settling time, and 57.9 mg L(-1) of FeCl3, 300 mg L(-1) of microspheres and a flocculation rate of 40 rpm in the E-DAF process. A linear correlation was observed between final O&G concentration and turbidity after E-DAF. In order to polish the O&G content of the effluent even further, to remove soluble compounds as phenol and to take advantage of residual iron after these treatments, Fenton and...
One of the most significant factors for a good performance and cost effectively operating a rever... more One of the most significant factors for a good performance and cost effectively operating a reverse osmosis desalination plant is the capacity of the pre-treatment to consistently produce high quality feed water. The use of low pressure filtration membranes pre-treatment become important in the last years because of the potential benefits compared with conventional, in terms of improved water quality, fewer RO cleanings and lower pressure drops. In the present work, different commercial NF membranes have been hydraulically characterized with synthetic seawater and analysed with FTIR-ATR, SEM, AFM and streaming potential. The results give us an evaluation of each membrane for their potential use as pretreatment for a RO desalination plant.
Retema Revista Tecnica De Medio Ambiente, 2012