H. Bruning | Wageningen University (original) (raw)
Papers by H. Bruning
When performing electrodialysis (ED) to desalinate a stream, both the energy for desalination and... more When performing electrodialysis (ED) to desalinate a stream, both the energy for desalination and the energy for pumping contribute to the total energy consumption, although under typical working conditions (e.g., brackish water desalination) the latter is usually negligible. However, the energy penalty might increase when desalinating viscous mixtures (i.e., viscosity of 2–20 cP). In this work, we experimentally investigate the desalination performance of an ED-unit operating with highly viscous water-polymer mixtures. The contribution of desalination and pumping energy to the total energy consumption was measured while varying diverse parameters, i.e., salinity and viscosity of the feed, and geometry and thickness of the spacer. It was found that the type of spacer did not significantly influence the energy required for desalination. The pumping energy was higher than predicted, though in most cases minimal compared to the energy for desalination. Only when using thin spacers (300...
Desalination
Concentration polarization and fouling hamper the desalination of polymer-flooding produced water... more Concentration polarization and fouling hamper the desalination of polymer-flooding produced water (PFPW) via electrodialysis (ED). This water is an abundant by-product from the oil and gas industry. A common technique to mitigate both problems is the application of pulsed electric field (PEF), which consists in supplying a constant current during a short time (pulse) followed by a time without current (pause). Accordingly, this work evaluated the application of PEF during the ED of PFPW to improve the process performance and to reduce fouling incidences. The experimental work consisted in performing ED batch runs in a laboratory-scale stack containing commercial ion exchange membranes. Synthetic PFPW was desalinated under different operating regimes until a fixed number of charges were passed. After each experiment, a membrane pair was recovered from the stack and analyzed through diverse techniques. The application of PEF improved the ED performance in terms of demineralization percentage and energy consumption, the latter having reductions of 36% compared to the continuous mode. In general, the shorter the pulses, the higher the demineralization rate and the lower the energy consumption. Regarding the application of different pause lengths, longer pauses yielded lower energy consumptions, but also lower demineralization. Amorphous precipitates composed of polymer and calcium fouled most on the anion and cation exchange membranes, independently of the applied current regime, but in a
Applied Catalysis B: Environmental
Abstract The aim of this study was to evaluate the use of self-organized TiO2 nanotube arrays (TN... more Abstract The aim of this study was to evaluate the use of self-organized TiO2 nanotube arrays (TNAs) as immobilized catalyst and UV-LED as light source (UV-LED/TNAs) for photocatalytic degradation of the β-blocker metoprolol (MTP) from aqueous solution. Firstly we employed electrochemical anodization to synthesize self-organized TNAs, and the effect of anodization potential and annealing temperature was examined. Characterization by SEM demonstrated a linear relation between the diameter of TiO2 nanotubes produced and the anodization potential, while Raman measurement revealed the vital role of annealing on crystallographic composition of the anodic produced TiO2 nanotubes. Regarding their performance in photocatalytic MTP degradation, surface morphology and crystallographic composition of the TNAs were found to impose crucial influence: only TNAs with diameter not smaller than 53 nm enabled rapid MTP degradation, and highest MTP degradation was obtained when a mixture of anatase and rutile were present in the TNAs. Secondly, the effect of operational parameters, i.e initial MTP concentration, pH, was investigated. Initial MTP concentration at low level had no detrimental effect on the process performance. Rapid MTP degradation and high total removal were achieved in a wide pH range (3–11). To evaluate the applicability of TNAs for water treatment, experiments were first carried out in the presence of three different commonly present water constituents, i.e bicarbonate ions, phosphate ions, and natural organic matters (NOMs). The results show that bicarbonate and phosphate ions have no inhibitory effect at concentration levels up to 200 mg/L, and NOMs exhibit detrimental effect when their concentration exceeds 5 mg/L. The total removal MTP degradation reduced from 87.09 ± 0.09% to 62.05 ± 0.08% when tap water samples were applied, demonstrating reasonable efficacy for practical applications. Regarding the degradation mechanism, formic acid and tert-butanol were added as scavenger for photo-generated holes (h+) and hydroxyl radicals (·OH), respectively. The obtained results demonstrate that primary degradation process occurred in liquid phase with participation of hydroxyl radicals in the liquid phase (·OH liquid), while smaller portion of MTP were degraded on the catalysis surface via reaction with h+ and hydroxyl radicals adsorbed on the catalyst surface (·OH surface). Other reactive species, e.g photo generated electrons and superoxide radical anions, did also play a minor role in MTP degradation. The mechanistic aspect was further confirmed by identification of degradation products by LC–MS/MS. The TNAs exhibited good stability after repeated use under varied operation conditions.
Environmental Technology, 2002
Acta Crystallographica Section A Foundations of Crystallography, 1992
An algorithm for calculating the scattering factors of atomic fragments in molecules as defined b... more An algorithm for calculating the scattering factors of atomic fragments in molecules as defined by the Stockholder recipe is presented. This method allows the calculation, from ab initio molecular wave functions, of structure factors including individual anisotropic atomic temperature factors. These structure factors agree with the model used in most leastsquares multipole-refinement procedures. Calculations on the H20 molecule illustrate the method.
Journal of Membrane Science
Abstract The presence of multivalent ions in polymer-flooding produced water (PFPW) hampers its r... more Abstract The presence of multivalent ions in polymer-flooding produced water (PFPW) hampers its recycling mainly because i) they increase the risk of scaling and reservoir souring (sulfate), ii) they interfere with the viscosifying effect of the fresh polyelectrolyte. It is desirable to achieve the removal of most multivalent ions without completely desalting the stream. With the adequate process conditions, electrodialysis could help to achieve this goal, so this work focused on evaluating the removal of divalent ions from synthetic PFPW through varying operational conditions. The experimental work consisted on batch experiments run in an electrodialysis-stack composed of strong Neosepta ion-exchange membranes. Synthetic PFPW solutions containing a mixture of monovalent and divalent ions were desalted at four different current densities, and three different temperatures. Additionally, the effect of the dissolved polymer on the removal was assessed by performing half of the experiments on polymer-containing solutions and half of them on solutions without it. Our results demonstrate that it is possible to achieve preferential removal of divalent cations (calcium and magnesium) through electrodialysis, especially when employing low current densities (24 A/m2) and high temperature (40 °C). The removal of sulfate, a divalent anion, is also accelerated in these conditions. The presence of polyelectrolyte did not significantly affect the removal rate of divalent ions. Thus, it is concluded that meticulous application of ED to minimize concentrations of divalent ions in PFPW is a potential effective way for water and polymer recycling in enhanced oil recovery situations, as an alternative to the use of other non-selective desalination technologies.
Household or domestic biogas plants constitute a growing sub-sector of the anaerobic digestion in... more Household or domestic biogas plants constitute a growing sub-sector of the anaerobic digestion industry worldwide, but had received low research attention for improvements. The Chinese dome digester (CDD), a major type of domestic biogas plant, is a naturally mixed, unheated and low tech system that is mainly used in rural areas. In this study, a multiphase computational fluid dynamics (CFD) model was applied to evaluate and subsequently improve mixing in a lab scale Chinese dome digester. The normal Chinese dome digester (CDD1) and two baffle configurations were investigated to improve the hydraulic mixing in the digester (CDD2 and CDD3 respectively) . 2D time dependent numerical simulations were done with the three-phase, phase field model in COMSOL Multiphysics in a CDD geometry. Residence time distribution (RTD) curves were derived for all the configurations to evaluate and compare performances. In addition, three hydraulic indicators were also studied to evaluate mixing improve...
Journal of Colloid and Interface Science
Critical Reviews in Environmental Science and Technology
Household digesters are anaerobic reactors applied mostly in rural areas of developing countries ... more Household digesters are anaerobic reactors applied mostly in rural areas of developing countries with tropical climate. The Chinese dome digester is the most popular household digester type in Asia and Africa, and has become the basis for contemporary developments in the household digester sector around the world. Household digesters are operated at ambient temperatures and have no internal mixing device, making them simple to operate. In the absence of internal mixing mechanism, the Chinese dome digester is mixed via pressure variation during gas production, gas use and feeding. Since mixing is limited in household digesters, they are operated at low organic loading rates and long hydraulic retention time when compared with forced mixed reactors. This review analyses and presents the various types of domestic biogas plants and operating parameters, with emphasis on mixing. Experimental results of household reactors, forced mixed reactors with different mixing modes and intensities were also reviewed and compared.
This study presents fluidized bed electrodes as a new device for disinfection. In the fluidized b... more This study presents fluidized bed electrodes as a new device for disinfection. In the fluidized bed electrodes system, granular activated carbon particles were suspended, and an alternating radio frequency electric field was applied over the suspended bed. Proof-of-principle studies with the luminescent non-pathogenic bacterium Escherichia coli YMc10 demonstrated that disinfection with fluidized bed electrodes requires both the presence of granular activated carbon particles and the application of radio frequency electric field. Disinfection was investigated at various frequencies in range from 80 to 200 kHz at electric field strength of 6 ± 0.5 V/cm during 6 h. The largest decrease of E. coli viable cell concentration in the liquid (from 10 8 to 10 6 CFU/mL) was obtained at an optimum frequency of 140 kHz. Possible mechanisms of this electromediated disinfection are discussed in the manuscript. The results are promising for development of a new disinfection process with fluidized bed electrodes.
Journal of Colloid and Interface Science
Desalination
The reuse of polymer flooding produced water (PFPW) generated in oil and gas industry is limited ... more The reuse of polymer flooding produced water (PFPW) generated in oil and gas industry is limited by its salt content, making desalination by electrodialysis a promising treatment option. Therefore, this study aimed to 1) assess the technical feasibility of employing electrodialysis to desalinate PFPW generated in assorted scenarios, and 2) evaluate the reuse of the electrodialysis-desalted water to confect polymer-flooding solution. The experimental work involved desalting two kinds of synthetic PFPW solutions, one with relatively low salinity (TDS = 5000 mg/L, brackish PFPW), and another with high salinity (TDS = 32,000 mg/L, sea PFPW), at two different temperatures, and later reusing the desalted solution to prepare viscous solutions. For the electrodialysis runs, the effects of feed composition and temperature on water transport, energy consumption and current efficiency were analyzed. It was found that the presence of polymer did not significantly influence the water transport rate or the specific energy consumption for the seawater cases, but had a measurable effect when desalting brackish water at 20°C. It was also found that some polymer remained in the stack, the loss occurring faster for the brackish PFPW. Still, both kinds of reused PFPW probed adequate to be employed as a basis for preparing n polymer solution.
Ciência & Engenharia
This research aimed at studying the oxidation process, to verify the effectiveness of coliform in... more This research aimed at studying the oxidation process, to verify the effectiveness of coliform inactivation and to evaluate the formation of ozonation disinfection byproducts (DBP) in anoxic sanitary wastewater treated with ozone/hydrogen peroxide applied at doses of 2.6 mg O 3 L-1 and 2.0 mg H 2 O 2 L-1 with contact time of 10 min and 8.1 mg O 3 L-1 and 8.0 mg H 2 O 2 L-1 with contact time of 20 min. The mean chemical oxygen demand (COD) reductions were 7.50 and 9.40% for applied dosages of 2.5-2.8 and 6.4-9.4 mg O 3 L-1 + 2.0 and 8.0 mg H 2 O 2 .L-1 , respectively. The Escherichia coli (E. coli) inactivation range was 2.98-4.04 log 10 and the total coliform inactivation range was 2.77-4.01 log 10. The aldehydes investigated were formaldehyde, acetaldehyde, glyoxal and methylglyoxal. It was observed only the formation of acetaldehyde that ranged 5.53 to 29.68 µg L-1 .
Journal of Photochemistry and Photobiology A: Chemistry
When performing electrodialysis (ED) to desalinate a stream, both the energy for desalination and... more When performing electrodialysis (ED) to desalinate a stream, both the energy for desalination and the energy for pumping contribute to the total energy consumption, although under typical working conditions (e.g., brackish water desalination) the latter is usually negligible. However, the energy penalty might increase when desalinating viscous mixtures (i.e., viscosity of 2–20 cP). In this work, we experimentally investigate the desalination performance of an ED-unit operating with highly viscous water-polymer mixtures. The contribution of desalination and pumping energy to the total energy consumption was measured while varying diverse parameters, i.e., salinity and viscosity of the feed, and geometry and thickness of the spacer. It was found that the type of spacer did not significantly influence the energy required for desalination. The pumping energy was higher than predicted, though in most cases minimal compared to the energy for desalination. Only when using thin spacers (300...
Desalination
Concentration polarization and fouling hamper the desalination of polymer-flooding produced water... more Concentration polarization and fouling hamper the desalination of polymer-flooding produced water (PFPW) via electrodialysis (ED). This water is an abundant by-product from the oil and gas industry. A common technique to mitigate both problems is the application of pulsed electric field (PEF), which consists in supplying a constant current during a short time (pulse) followed by a time without current (pause). Accordingly, this work evaluated the application of PEF during the ED of PFPW to improve the process performance and to reduce fouling incidences. The experimental work consisted in performing ED batch runs in a laboratory-scale stack containing commercial ion exchange membranes. Synthetic PFPW was desalinated under different operating regimes until a fixed number of charges were passed. After each experiment, a membrane pair was recovered from the stack and analyzed through diverse techniques. The application of PEF improved the ED performance in terms of demineralization percentage and energy consumption, the latter having reductions of 36% compared to the continuous mode. In general, the shorter the pulses, the higher the demineralization rate and the lower the energy consumption. Regarding the application of different pause lengths, longer pauses yielded lower energy consumptions, but also lower demineralization. Amorphous precipitates composed of polymer and calcium fouled most on the anion and cation exchange membranes, independently of the applied current regime, but in a
Applied Catalysis B: Environmental
Abstract The aim of this study was to evaluate the use of self-organized TiO2 nanotube arrays (TN... more Abstract The aim of this study was to evaluate the use of self-organized TiO2 nanotube arrays (TNAs) as immobilized catalyst and UV-LED as light source (UV-LED/TNAs) for photocatalytic degradation of the β-blocker metoprolol (MTP) from aqueous solution. Firstly we employed electrochemical anodization to synthesize self-organized TNAs, and the effect of anodization potential and annealing temperature was examined. Characterization by SEM demonstrated a linear relation between the diameter of TiO2 nanotubes produced and the anodization potential, while Raman measurement revealed the vital role of annealing on crystallographic composition of the anodic produced TiO2 nanotubes. Regarding their performance in photocatalytic MTP degradation, surface morphology and crystallographic composition of the TNAs were found to impose crucial influence: only TNAs with diameter not smaller than 53 nm enabled rapid MTP degradation, and highest MTP degradation was obtained when a mixture of anatase and rutile were present in the TNAs. Secondly, the effect of operational parameters, i.e initial MTP concentration, pH, was investigated. Initial MTP concentration at low level had no detrimental effect on the process performance. Rapid MTP degradation and high total removal were achieved in a wide pH range (3–11). To evaluate the applicability of TNAs for water treatment, experiments were first carried out in the presence of three different commonly present water constituents, i.e bicarbonate ions, phosphate ions, and natural organic matters (NOMs). The results show that bicarbonate and phosphate ions have no inhibitory effect at concentration levels up to 200 mg/L, and NOMs exhibit detrimental effect when their concentration exceeds 5 mg/L. The total removal MTP degradation reduced from 87.09 ± 0.09% to 62.05 ± 0.08% when tap water samples were applied, demonstrating reasonable efficacy for practical applications. Regarding the degradation mechanism, formic acid and tert-butanol were added as scavenger for photo-generated holes (h+) and hydroxyl radicals (·OH), respectively. The obtained results demonstrate that primary degradation process occurred in liquid phase with participation of hydroxyl radicals in the liquid phase (·OH liquid), while smaller portion of MTP were degraded on the catalysis surface via reaction with h+ and hydroxyl radicals adsorbed on the catalyst surface (·OH surface). Other reactive species, e.g photo generated electrons and superoxide radical anions, did also play a minor role in MTP degradation. The mechanistic aspect was further confirmed by identification of degradation products by LC–MS/MS. The TNAs exhibited good stability after repeated use under varied operation conditions.
Environmental Technology, 2002
Acta Crystallographica Section A Foundations of Crystallography, 1992
An algorithm for calculating the scattering factors of atomic fragments in molecules as defined b... more An algorithm for calculating the scattering factors of atomic fragments in molecules as defined by the Stockholder recipe is presented. This method allows the calculation, from ab initio molecular wave functions, of structure factors including individual anisotropic atomic temperature factors. These structure factors agree with the model used in most leastsquares multipole-refinement procedures. Calculations on the H20 molecule illustrate the method.
Journal of Membrane Science
Abstract The presence of multivalent ions in polymer-flooding produced water (PFPW) hampers its r... more Abstract The presence of multivalent ions in polymer-flooding produced water (PFPW) hampers its recycling mainly because i) they increase the risk of scaling and reservoir souring (sulfate), ii) they interfere with the viscosifying effect of the fresh polyelectrolyte. It is desirable to achieve the removal of most multivalent ions without completely desalting the stream. With the adequate process conditions, electrodialysis could help to achieve this goal, so this work focused on evaluating the removal of divalent ions from synthetic PFPW through varying operational conditions. The experimental work consisted on batch experiments run in an electrodialysis-stack composed of strong Neosepta ion-exchange membranes. Synthetic PFPW solutions containing a mixture of monovalent and divalent ions were desalted at four different current densities, and three different temperatures. Additionally, the effect of the dissolved polymer on the removal was assessed by performing half of the experiments on polymer-containing solutions and half of them on solutions without it. Our results demonstrate that it is possible to achieve preferential removal of divalent cations (calcium and magnesium) through electrodialysis, especially when employing low current densities (24 A/m2) and high temperature (40 °C). The removal of sulfate, a divalent anion, is also accelerated in these conditions. The presence of polyelectrolyte did not significantly affect the removal rate of divalent ions. Thus, it is concluded that meticulous application of ED to minimize concentrations of divalent ions in PFPW is a potential effective way for water and polymer recycling in enhanced oil recovery situations, as an alternative to the use of other non-selective desalination technologies.
Household or domestic biogas plants constitute a growing sub-sector of the anaerobic digestion in... more Household or domestic biogas plants constitute a growing sub-sector of the anaerobic digestion industry worldwide, but had received low research attention for improvements. The Chinese dome digester (CDD), a major type of domestic biogas plant, is a naturally mixed, unheated and low tech system that is mainly used in rural areas. In this study, a multiphase computational fluid dynamics (CFD) model was applied to evaluate and subsequently improve mixing in a lab scale Chinese dome digester. The normal Chinese dome digester (CDD1) and two baffle configurations were investigated to improve the hydraulic mixing in the digester (CDD2 and CDD3 respectively) . 2D time dependent numerical simulations were done with the three-phase, phase field model in COMSOL Multiphysics in a CDD geometry. Residence time distribution (RTD) curves were derived for all the configurations to evaluate and compare performances. In addition, three hydraulic indicators were also studied to evaluate mixing improve...
Journal of Colloid and Interface Science
Critical Reviews in Environmental Science and Technology
Household digesters are anaerobic reactors applied mostly in rural areas of developing countries ... more Household digesters are anaerobic reactors applied mostly in rural areas of developing countries with tropical climate. The Chinese dome digester is the most popular household digester type in Asia and Africa, and has become the basis for contemporary developments in the household digester sector around the world. Household digesters are operated at ambient temperatures and have no internal mixing device, making them simple to operate. In the absence of internal mixing mechanism, the Chinese dome digester is mixed via pressure variation during gas production, gas use and feeding. Since mixing is limited in household digesters, they are operated at low organic loading rates and long hydraulic retention time when compared with forced mixed reactors. This review analyses and presents the various types of domestic biogas plants and operating parameters, with emphasis on mixing. Experimental results of household reactors, forced mixed reactors with different mixing modes and intensities were also reviewed and compared.
This study presents fluidized bed electrodes as a new device for disinfection. In the fluidized b... more This study presents fluidized bed electrodes as a new device for disinfection. In the fluidized bed electrodes system, granular activated carbon particles were suspended, and an alternating radio frequency electric field was applied over the suspended bed. Proof-of-principle studies with the luminescent non-pathogenic bacterium Escherichia coli YMc10 demonstrated that disinfection with fluidized bed electrodes requires both the presence of granular activated carbon particles and the application of radio frequency electric field. Disinfection was investigated at various frequencies in range from 80 to 200 kHz at electric field strength of 6 ± 0.5 V/cm during 6 h. The largest decrease of E. coli viable cell concentration in the liquid (from 10 8 to 10 6 CFU/mL) was obtained at an optimum frequency of 140 kHz. Possible mechanisms of this electromediated disinfection are discussed in the manuscript. The results are promising for development of a new disinfection process with fluidized bed electrodes.
Journal of Colloid and Interface Science
Desalination
The reuse of polymer flooding produced water (PFPW) generated in oil and gas industry is limited ... more The reuse of polymer flooding produced water (PFPW) generated in oil and gas industry is limited by its salt content, making desalination by electrodialysis a promising treatment option. Therefore, this study aimed to 1) assess the technical feasibility of employing electrodialysis to desalinate PFPW generated in assorted scenarios, and 2) evaluate the reuse of the electrodialysis-desalted water to confect polymer-flooding solution. The experimental work involved desalting two kinds of synthetic PFPW solutions, one with relatively low salinity (TDS = 5000 mg/L, brackish PFPW), and another with high salinity (TDS = 32,000 mg/L, sea PFPW), at two different temperatures, and later reusing the desalted solution to prepare viscous solutions. For the electrodialysis runs, the effects of feed composition and temperature on water transport, energy consumption and current efficiency were analyzed. It was found that the presence of polymer did not significantly influence the water transport rate or the specific energy consumption for the seawater cases, but had a measurable effect when desalting brackish water at 20°C. It was also found that some polymer remained in the stack, the loss occurring faster for the brackish PFPW. Still, both kinds of reused PFPW probed adequate to be employed as a basis for preparing n polymer solution.
Ciência & Engenharia
This research aimed at studying the oxidation process, to verify the effectiveness of coliform in... more This research aimed at studying the oxidation process, to verify the effectiveness of coliform inactivation and to evaluate the formation of ozonation disinfection byproducts (DBP) in anoxic sanitary wastewater treated with ozone/hydrogen peroxide applied at doses of 2.6 mg O 3 L-1 and 2.0 mg H 2 O 2 L-1 with contact time of 10 min and 8.1 mg O 3 L-1 and 8.0 mg H 2 O 2 L-1 with contact time of 20 min. The mean chemical oxygen demand (COD) reductions were 7.50 and 9.40% for applied dosages of 2.5-2.8 and 6.4-9.4 mg O 3 L-1 + 2.0 and 8.0 mg H 2 O 2 .L-1 , respectively. The Escherichia coli (E. coli) inactivation range was 2.98-4.04 log 10 and the total coliform inactivation range was 2.77-4.01 log 10. The aldehydes investigated were formaldehyde, acetaldehyde, glyoxal and methylglyoxal. It was observed only the formation of acetaldehyde that ranged 5.53 to 29.68 µg L-1 .
Journal of Photochemistry and Photobiology A: Chemistry