Reverse electrodialysis: potential reduction in energy and emissions of desalination

Salinity gradient energy harvesting by reverse electrodialysis (RED) is a promising renewable source to decarbonize desalination. This work surveys the potential reduction in energy consumption and carbon emissions gained from RED integration in 20 medium-to-large-sized seawater reverse osmosis (SWRO) desalination plants spread worldwide. Using the validated RED system’s model from our research group, we quantified the grid mix share of the SWRO plant’s total energy demand and total emissions RED would abate (i) in its current state of development and (ii) if captured all salinity gradient exergy (SGE). Results indicate that more saline and warmer SWRO brines enhance RED’s net power density, yet source availability may restrain specific energy supply. If all SGE were harnessed, RED could supply ~40% of total desalination plants’ energy demand almost in all locations, yet energy conversion irreversibility and untapped SGE decline it to ~10%. RED integration in the most emission-intensive SWRO plants could relieve up to 1.95 kg CO2-eq m−3. Findings reveal that RED energy recovery from SWRO concentrate effluents could bring desalination sector sizeable energy and emissions savings provided future advancements bring RED technology closer to its thermodynamic limit.This research was funded by the LIFE programme (LIFE19 ENV/ES/000143) and the Spanish Ministry of Science, Innovation and Universities (RTI2018-093310-B-I00 and CTM2017-87850-R, and the FPI grant awarded to C.T., PRE2018-086454)

La organización de los servicios públicos sanitarios : actas de las Jornadas de estudio celebradas en la Universidad Carlos III de Madrid los días 10 y 11 de abril de 2000

PRIMERA PARTE: Las bases constitucionales. Luciano Parejo Alfonso. Constitución, Sistema Nacional de Salud y formas de organización -- SEGUNDA PARTE: Economía y derecho en la organización sanitaria. Vicente Ortún Rubio. Organización de los servicios sanitarios en el estado del bienestar -- Ángel Menéndez Rexach. Formas jurídicas de gestión de los servicios sanitarios -- TERCERA PARTE: Los modelos organizativos del INSALUD y las Comunidades Autónomas. Félix Lobo. Prefacio -- Iñaki Fernández Mendizábal. Alguna reflexión en torno a la organización de los servicios públicos sanitarios y las nuevas formas de gestión -- Guillem Lopez i Casanovas. La financiación automómica de la sanidad. Algunas afirmaciones, valoraciones y constataciones -- Javier Rey del Castillo. La organización territorial de los servicios públicos sanitarios -- Javier Sánchez-Caro. Régimen jurídico de las nuevas formas de gestión en la sanidad española (la perspectiva del Instituto Nacional de Salud) -- Norberto Sanfrutos Velázquez. Las experiencias de gestión en los servicios sanitarios públicos en Andalucía -- CUARTA PARTE: La forma y los medios de la organización. Algunos aspectos polémicos. José Luis Piñar Mañas. Reforma Sanitaria ¿privatización a través de fundaciones? -- Marcos Vaquer Caballería. Las fundaciones como forma de gestión directa de los servicios sanitarios: las enseñanzas de una experiencia truncada -- Alberto Palomar Olmeda. Formas de organización y régimen de personal de los servicios públicos sanitarios -- Juan Zornoza Pérez. Formas de organización y régimen económico-financiero de los servicios públicos sanitarios

A generalized disjunctive programming model for the optimal design of reverse electrodialysis process for salinity gradient-based power generation

Reverse electrodialysis (RED) is an emerging electro-membrane technology that generates electricity out of salinity differences between two solutions, a renewable source known as salinity gradient energy. Realizing full-scale RED would require more techno-economic and environmental assessments that consider full process design and operational decision space from the RED stack to the entire system. This work presents an optimization model formulated as a Generalized Disjunctive Programming (GDP) problem that incorporates a finite difference RED stack model from our research group to define the cost-optimal process design. The solution to the GDP problem provides the plant topology and the RED units´ working conditions that maximize the net present value of the RED process for given RED stack parameters and site-specific conditions. Our results show that, compared with simulation-based approaches, mathematical programming techniques are efficient and systematic to assist early-stage research and to extract optimal design and operation guidelines for large-scale RED implementation.This work was supported by the LIFE Programme of the European Union (LIFE19 ENV/ES/000143); the MCIN/AEI/10.13039/501100011033 and “European Union NextGenerationEU/PRTR” (PDC2021–120786-I00); and by the MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future” (PRE2018–086454)

Generalized disjunctive programming model for optimization of reverse electrodialysis process

Reverse electrodialysis (RED), an emerging electrochemical technology that uses ion-selective membranes to directly draw electricity out from salinity differences between two solutions, i.e., salinity gradient energy (SGE), has the potential to be a clean and steady renewable source to reach a sustainable water and energy supply portfolio. Although RED has made notable advances, full-scale RED progress demands more techno-economic and environmental assessments that consider full process design and operational decision space from module- to system-level. This work presents an optimization model formulated as a Generalized Disjunctive Programming (GDP) problem to define the cost-optimal RED process design for different deployment scenarios. We use a predictive model of the RED stack developed and validated in our research group to fully capture the behavior of the system. The problem addressed is to determine the RED plant's topology and the working conditions for a given design of each RED stack which renders the cost-optimal design for the defined problem and scenario. Our results show that, compared with simulation-based approaches, mathematical programming techniques are an efficient and systematic approach to provide decision-making support in early-stage applied research and to obtain design and operation guidelines for full-scale RED implementation in real scenarios.Project LIFE19 ENV/ES/000143 funded by the LIFE Programme of the European Union. Grant PDC2021-120786- I00 funded by MCIN/AEI/10.13039/501100011033 and by the “European Union NextGenerationEU/PRTR”. Grant PRE2018-086454 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”

Life cycle assessment of salinity gradient energy recovery by reverse electrodialysis in a seawater reverse osmosis desalination plant

Salinity gradient energy capture by reverse electrodialysis (SGE-RED) can play a part in the shift away from fossil fuels towards a carbon-neutral renewable energy supply; however, like other renewable power technologies, SGE-RED environmental soundness hinges on its whole life-cycle environmental loads. This study surveys the Life Cycle Assessment of SGE-RED technology. We quantified (i) the environmental loads per 1.0 kW h generated by a stand-alone RED unit and then, (ii) the environmental burdens related to the energy provision from an up-scaled RED system to a seawater reverse osmosis (SWRO) desalination plant per 1.0 m3 of desalted water. The RED unit's assessment results show that SGE-RED is environmentally competitive with other renewable sources such as photovoltaics or wind. Regarding the component's contribution analysis, the spacer's fabric material drives the RED environmental burden as the number of cell pairs is increased. The scaling-up of the RED unit, however, improves its full environmental profile. Preliminary results of SGE-RED combination with a SWRO plant suggest that the energy harnessed from SWRO's concentrate streams by RED could enhance the environmental performance of the desalination industry. Further research is required to identify SWRO-RED design alternatives that minimize the life cycle burden while still yielding good technical and economic performance.This work was supported by the Community of Cantabria - Regional Plan through the project Gradisal (RM16-XX-046-SODERCAN/FEDER); and the Spanish Ministry of Science, Innovation and Universities (RTI2018-093310-B-I00 and CTM2017-87850-R). Carolina Tristán is supported by the Spanish Ministry of Science, Innovation and Universities (FPI grant PRE2018-086454). The authors also thank Fumatech for providing information on IEMs properties

Blue energy for sustainable water reclamation in WWTPs

The benefits of wastewater (WW) reclamation to alleviate the stress of freshwater resources are counterbalanced by the required energy demand to drive the treatments. This handicap can be considerably minimized when renewable energy sources are integrated to perform this process, increasing the environmental and energy sustainability of the reclamation process. This work reports the assessment of a new strategy for WW reclamation in shoreline wastewater treatment plants (WWTPs) through the conversion of the salinity gradient energy (SGE) generated in the contact between reclaimed water (RW) and seawater (SW) to electricity by the use of reverse electrodialysis (RED). Secondary effluents from the selected WWTP were further treated by a simple remediation process consisting of coagulation-flocculation and solids removal, ending with a filtration stage; the obtained RW contained 0.008 M NaCl and was used as low concentrated solution in the RED stack; besides, filtered SW with 0.5 M NaCl, was employed as high concentrated solution. The plant run for 480 h, reaching gross power up to 1.43 W/m2 without decay along the operation time indicating that no fouling issues appeared in this time period. This represents a great improvement in comparison to the results published in the literature so far; the slight increase in the salinity of RW still allowed for its further reuse. Thus, a novel and energy sustainable strategy to promote WW reclamation with simultaneous SGE recovery is presented.The authors want to acknowledge financial support from the Community of Cantabria - Regional Plan for the project: Gradisal “RM16-XX-046-SODERCAN/FEDER”, as well as the projects funded by the Spanish Ministry of Economy and Competitiveness CTQ2015-66078-R, and CTM2017-87850-R. This research is also being supported by the Project “HYLANTIC”-EAPA_204/2016, which is co-financed by the European Regional Development Fund in the framework of the Interreg Atlantic program

Efficiency of a self-administered outpatient parenteral antimicrobial therapy (s-opat) for infectiveendocarditis within the context of a shortened hospital admission based on hospital at homeprogram

OBJECTIVE: This study aimed to evaluate the efficiency of treatment of infectious endocarditis (IE) via Self-administered Outpatient Parenteral Antimicrobial Therapy (S-OPAT) supported by a shortening hospital admission program in a hospitalization-at-home unit (HAH), including a short review of the literature. METHODS: Ambispective cohort study of 57 episodes of IE in 54 patients treated in an HAH unit between 1988 and 2014 who receive S-OPAT after prior intra-hospital clinical stabilization. Characteristics of each episode of IE, safety and efficiency of the care model, were analyzed. RESULTS: Forty-three (76%) patients were males with a median age of 61 years (SD = 16.5). A total of 37 (65%) episodes affected the native valve (42% the aortic valve). In 75%, a micro-organism was isolated, of which 88% were Gram-positive bacteria. No deaths occurred during HAH program, clinical complications appeared in 30% of episodes, only 6 patients were re-admitted to hospital although no patient died. In the 12 months' follow-up 3 cases had a recurrence. The average cost of a day stay in HAH was €174 while in traditional cardiology hospitalization was €1100. The total average cost of treatment of each episode of IE managed entirely in hospital was calculated as €54,723. Application of the S-OPAT model based on HAH meant a cost reduction of 32.72%. CONCLUSIONS: In suitably selected patients, treatment of IE based on S-OPAT supported by a shortening hospital admission care program by means of referral to a HAH unit is a safe and efficient care model which entails a significant cost saving for the public healthcare system

Antibacterial Effect of Hypochlorous Acid on Bacteria Associated with the Formation of Periodontal Biofilms: An in vitro Pilot Study

Objective: To evaluate the antibacterial effect of electrolytically generated hypochlorous acid on Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. Material and Methods: In this in vitro experiment, the effect of hypochlorous acid (HOCl) on the strains S. gordonii, F. nucleatum, and P. gingivalis was evaluated using 4% sodium hypochlorite, 0.12% chlorhexidine, and distilled water as controls. The four groups were placed on each plate, and each group was replicated five times. The agar diffusion method by zones measurement was used. The data were processed with SPSS using the Kruskal-Wallis test and multiple comparison tests. Results: Hypochlorous acid showed an average inhibition halo of 9.28 mm on S. gordonii. As expected with distilled water, no zone of inhibition was noted for any of the bacteria, nor were zones of inhibition observed with HOCl for F. nucleatum and P. gingivalis. Conclusion: Hypochlorous acid showed antimicrobial properties against only S. gordonii and was less effective than 4% sodium hypochlorite and 0.12% chlorhexidine, although no significant differences were found between the latter

The effectiveness of a smartphone application on modifying the intakes of macro and micronutrients in primary care: a randomized controlled trial. The EVIDENT II Study

Background: This study evaluates the effectiveness of adding a diet smartphone application to standard counseling to modify dietary composition over the long term (12 months). Methods: A randomized, controlled, multicenter clinical trial was conducted involving the participation of 833 subjects from primary care clinics (415 to the intervention (counseling + application) group (IG) and 418 to the control (counseling) group (CG)). Both groups were counseled about a healthy diet and physical activity. For the 3-month intervention period, the IG was also trained to use a diet smartphone application that involved dietary self-monitoring and tailored feedback. Nutritional composition was estimated using a self-reported food frequency questionnaire. Results: An analysis of repeated measures revealed an interaction between the group and the percentages of carbohydrates (p = 0.031), fats (p = 0.015) and saturated fats (p = 0.035) consumed. Both groups decreased their energy intake (Kcal) at 12 months (IG: −114 (95% CI: −191 to −36); CG: −108 (95% CI: −184 to −31)). The IG reported a higher percentage intake of carbohydrates (1.1%; 95% CI: 0.1 to 2.0), and lower percentage intakes of fats (−1.0%; 95% CI: −1.9 to −0.1) and saturated fats (−0.4%; 95%CI: −0.8 to −0.1) when compared to the CG. Conclusions: Better results were achieved in terms of modifying usual diet composition from counseling and the diet smartphone application compared to counseling alone. This was evaluated by a self-reported questionnaire, which indicated an increased percentage intake of carbohydrates, and decreased percentage intakes of fats and saturated fatsSpanish Ministry of Science and Innovation (MICINN) and the Carlos III Health Institute/European Regional Development Fund (ERDF) (FIS: PI13/00618, PI13/01526, PI13/00058, PI13/01635, PI13/02528, PI12/01474; RETICS: RD12/0005, RD16/0007), Regional Health Management of Castilla and León (GRS 1191/B/15, GRS 909/B/14, GRS 770/B/13) and the Infosalud Foundatio

Recovery of salinity gradient energy in desalination plants by reverse electrodialysis

Salinity gradient energy (SGE) capture by reverse electrodialysis (RED) is an emerging technology to advance the phaseout of conventional water-intensive energy sources in desalination industry. This paper assesses SGE recovery potential of an up-scaled RED system in seawater reverse osmosis (SWRO) desalination plants. Using a detailed RED system's model (i) we conducted a parametric evaluation of feed's concentration, feed's flow rate, and temperature to identify the optimal working conditions of an industrial-scale RED unit; (ii) we estimated SGE recovery of a RED plant in SWRO plants distributed worldwide, adopting a single-stage arrangement of the RED units; (iii) finally, to enhance energy yield, we examined different RED plant's layouts in a specific SWRO plant. The results underline the merits of this modelling tool to assist SGE-RED implementation in the utmost scenarios. Regarding RED plant's layout, findings reveal that the series-parallel arrangement of the RED units improves the power output and energy yield of the system but requires more RED units. Hence, a systematic evaluation through optimization of the hybrid process's configuration both at plant's scale and at RED unit's scale is needed to properly determine RED's SGE recovery potential from waste streams in SWRO plants.This work was supported by the Community of Cantabria - Regional Plan through the project Gradisal (RM16-XX-046-SODERCAN/FEDER); and the Spanish Ministry of Science, Innovation and Universities (RTI2018-093310-B-I00 and CTM2017-87850-R). Carolina Tristán is supported by the Spanish Ministry of Science, Innovation and Universities (FPI grant PRE2018-086454)