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This study explores the performance of an innovative, techno-efficient multigeneration plant incorporating a three-stage reverse osmosis (RO) unit, focusing on the exergy-cost-environment nexus. The plant's performance is validated through comparisons with existing literature, and parametric analyses are conducted to assess the impact of critical parameters. The system demonstrates the capability to produce 720.1 kW of net electricity and sustain a hydrogen production rate of 0.05083 kg/s, achieving energetic and exergetic efficiencies of 17.82% and 23.88%, respectively. Economically, the system offers a sum unit cost of products (SUCP) of 33.33 $/GJ, showcasing its financial viability. Environmental and sustainability metrics, including an emission rate of 0.000267 kg CO₂/kWh, an exergy stability factor of 0.9341, and an exergo-environment index of 17.21, underscore the plant's eco-efficiency. A sensitivity analysis of the RO membrane recovery rate reveals an optimal balance between improved performance and economic feasibility. Excessive recovery rates adversely impact costs. The economic evaluation, using the Net Present Value (NPV) method, indicates a payback period of 9 years with significant profitability projected by the 20th year. This comprehensive analysis confirms the plant's potential for efficient and sustainable multigeneration. • Proposing a cutting-edge multi-generation plant with environmental viability. • The economic analysis forecasts a return on investment within 9 years. • The minimization of reactor temperatures has positive effect on the performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tuning ammonium retention in membrane separation using the acid-base equilibrium. • Selectivity increase of nitrogen/potassium by selective permeation of neutral ammonia. • Dynamic digestate separation producing nitrogen and potassium enriched streams. Extensive nitrogen emissions with negative impact on nature and the environment urge effective valorization of manure and fractionation of nutrients to enable precision fertilization. Typically, manure is fed to a digester to produce biogas. The remaining digestate is then mechanically separated into a solid phosphorous-rich fraction and a liquid fraction containing both NH 4 + and K. These ions are difficult to separate due to their very identical size and charge. We show that with smart tuning of the pH to control the NH 3 /NH 4 + equilibrium, membranes can produce dedicated N and K-rich streams. The increased pH switches the equilibrium towards the neutrally charged solute NH 3 that permeates more easily through the membrane than charged NH 4 + and K+ ions. Experiments with both artificial NH 4 Cl/KCl mixtures as well as real liquid digestate and four different membrane types, ranging from open nanofiltration (NF) to sea water reverse osmosis (RO) membranes were performed. At neutral pH, no N/K selectivity was observed, not for single components nor for mixtures. When the pH was increased towards alkaline environment, distinct selectivity for N/K was obtained both with model solutions and real liquid digestate. At a suitable pH of 10, with >80 % of the total ammonia present as NH 3 , the RO BW membrane showed a large N/K selectivity of 35 in the crossflow system. Additional RO steps at low pH allows subsequent concentration of the formed NH 4 + and K+ fractions. The presented dynamic pH approach proofs that in a two-step RO system both N, and K-enriched fertilizers can be produced from real liquid digestate. [ABSTRACT FROM AUTHOR]

• Addresses the lack of on-site data for PFAS concentrations in landfill leachates across 11 Chinese cities. • Demonstrates high removal efficiencies of PFAS using DTRO systems, with an average of 94% for total PFAS. • Reveals a significant correlation between PFAS levels and regional economic development. • Indicates limited additional PFAS reduction by Na ion exchange resin following DTRO treatment. Per- and polyfluoroalkyl substances (PFAS), known for their persistent toxicity and mobility, pose significant environmental and human health risks. Here we explored the occurrence and efficacy of on-site Double-Pass Reverse Osmosis (DTRO) systems in removing 30 different PFAS from landfill leachates in 11 diverse cities across China. PFAS concentrations in landfill leachate ranged from 938 to 32,491 ng/L, averaging 6,486 ng/L, predominantly comprising short-chain PFAS, notably perfluorobutane sulfonate (PFBS). Notable emerging substitutes like 6:2 fluorotelomer sulfonate, fluorobutane sulfonamide, and 9-chlorohexadecafluoro-3-oxanone sulfonate were also identified. The PFAS levels correlated positively (r2 = 0.79, p < 0.01) with regional economic development, with coastal areas exhibiting higher concentrations than inland regions. The DTRO membrane filtration and ion exchange resin achieved an average removal efficiency of 94 % for ∑ 30 PFAS and even 99.97 % for PFBS (the concentration of PFBS in the raw leachate ranged from 226.36 ng/L to 27,935.61 ng/L, with an average concentration of 4,506.88 ng/L). The Na ion exchange resin had a limited effect on further reducing the PFAS concentration. Our findings not only contribute to the theoretical understanding of PFAS behavior in landfill leachates but also offer a practical engineering applications for global waste management practices. [ABSTRACT FROM AUTHOR]

This research investigates a sustainable and renewable mobile energy system designed for electricity production, hydrogen generation, and seawater desalination. It targets critical energy and freshwater needs during disaster scenarios, particularly in island nations and coastal cities where infrastructure may be compromised. The system integrates advanced technologies, including wind turbines, photovoltaic panels, solar collectors, and reverse osmosis units, all mounted on a green ship. Simulations using Engineering Equation Solver software indicate that in July, the system can produce 2,201,865 MJ of electricity, 7252 kg of hydrogen, and 3456 tons of fresh and hot water. This output can power 1072 electric vehicles and 1284 hydrogen-powered vehicles while supplying cold water to 57,600 people and hot water to 5760 people. By relying on renewable energy, the system prevents approximately 43,543 kg of carbon emissions in July. The total monthly economic value is estimated at $47,241.36, demonstrating its potential as a sustainable solution for disaster response and coastal communities. [Display omitted] • Hydrogen generation of the combined hybrid renewable system. • Thermodynamic efficiencies of components and overall the system for a green ship. • The comparison of the power generation of the wind turbine, Organic Rankine Cycle, and solar cell. • The monthly carbon saving quantity of the renewable hybrid system. [ABSTRACT FROM AUTHOR]

The main obstacles to reverse osmosis desalination processes are high energy intensity and long-term continuity. Temperature and pressure have the greatest and most significant effects on energy use. The main objectives of the current study are to determine the pressure and temperature-dependent optimal operating parameters for a membrane desalination unit. To determine the ideal operating settings for a membrane unit, the impact of changing pressure and temperature on its performance was investigated. These two elements are closely connected to the energy consumption per cubic meter under various operating situations. The present work is experimentally carried out in a research laboratory for capacity building and future research studies in the desalination field established in the National Center of Water Research – Egypt. This laboratory is Egypt's first multi-functional Desalination Research Station for seawater, brackish water, and related water treatment areas. The plant is equipped with online instrumentation and Data Acquisition System and 13 sensors for most physical parameters which economically affect membrane performance and desalination processes. These parameters, particularly pressure and temperature, are measured, evaluated and analyzed. According to the findings in this study, feed salinity and feed pressure both have significant impacts. At 13 bar pressure, the maximum salt rejection was 98.8%. When feed pressure is increased from 5 to 13 bars, there is a 73.3% decrease in permeate salinity. Additionally, applying a 13 bar feed pressure to water with a salinity of 1000 ppm results in the best water quality of 12 ppm. The relationship between feed pressure, brine salinity, and membrane water recovery appeared to be approximately linear and positive. More crucially, it was discovered that feed pressure, salinity, and water recovery are all constants for water permeability. A prototype for the maximum pressure (ranges from 15.6 to 10.8) and temperature (ranges from 21 to 35) at which the optimal recovery of the laboratory occurred was developed. Moreover, the developed prototype includes the corresponding permeate TDS and a specific energy for each optimal point. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Residual lipids (RL) in whey protein isolate (WPI) are detrimental to optimal functional applications (e.g., foaming and low turbidity) and contribute to off-flavor development during powder storage. The objective of this research was to prepare an experimental WPI by removing RL without using the traditional microfiltration process and compare its properties with commercially available WPI made using microfiltration and some other whey powders. We hypothesize that by adjusting the pH of whey to <5.0, we would be close to the isoelectric point of any remaining denatured proteins (DP) and phospholipoproteins (PLP), and therefore reduce electrostatic repulsion between these molecules. Furthermore, demineralization of the acidified whey protein solution by UF combined with diafiltration (DF) should reduce ionic hindrance to aggregation and thereby help with the aggregation of these DP as well as most RL; centrifugation or clarification could be used to remove these materials. Calcium should also be more extensively removed by this approach, which should improve the heat stability of the experimental WPI. Demineralization was achieved on a pilot scale by acidifying liquid (cheese) whey protein concentrate containing 34% protein (WPC-34) to pH 4.5 using HCl, and UF of the whey protein solution along with extensive DF using acidified (pH ∼3.5) reverse osmosis filtered water. Demineralized whey protein solution was adjusted to various combinations of pH (4.1–4.9), conductivities (500–2,000 μS/cm), and protein concentrations (1%–7%) and then centrifuged at 10,000 × g for 10 min. The effective sedimentation (precipitation) of RL in these treatments was estimated by measuring the turbidity of the supernatants. Maximum precipitation was observed at pH 4.5 to 4.7. Reducing conductivity via UF/DF increased the precipitation of RL due to reduced ionic hindrance to aggregation. Maximum sedimentation of RL was observed at protein concentrations ≤3% because of a higher density difference between the precipitate and serum phase. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis confirmed the sedimentation of phospholipoproteins, caseins, and DP upon isoelectric precipitation at pH ∼4.5, while native whey proteins or undenatured whey proteins remained soluble in the supernatant, unaffected by the pretreatment. To scale up the process, 750 L of fluid WPC-34 was acidified and demineralized by UF (volume concentration factor = 1.35) and DF until the permeate solids reached 0.1% (when desired demineralization was achieved), clarified using a pilot-scale desludging clarifier to remove RL, neutralized, ultrafiltered to concentrate the protein, and then spray-dried to produce an experimental WPI (91% protein and 1.8% fat on a dry basis [db]). In another trial, demineralized UF concentrate was clarified by gravity sedimentation and the supernatant was neutralized, ultrafiltered, and spray-dried to produce a second experimental WPI (91% protein and <1% fat db). These experimental WPI powders were compared with several commercially available WPI powders to assess functional properties such as solubility, heat stability, foamability and foam strength, gelation, and sensory attributes over accelerated storage. Experimental WPI had excellent functional properties, had low turbidity, were highly heat stable, and only developed very slight-to-slight off-flavors upon accelerated storage, and their properties were comparable to the WPI manufactured commercially using microfiltration even after accelerated storage. [ABSTRACT FROM AUTHOR]

The present article introduces and investigates a new approach for shaving the peak electricity demand and mitigating energy instability. At the heart of this concept is a smart integration for efficient hydrogen production/storage/usage to minimize energy costs and maximize the renewable penetration in the local electricity grid. The system is driven by a wind farm integrated with proton exchange membrane (PEM) electrolyzers and reverse osmosis desalination units for efficient electricity, hydrogen, and freshwater production. It also combines with PEM fuel cells equipped with a hydrogen tank to meet the demand constantly when renewable electricity is unavailable or unstable. The system's practicality is assessed and compared for various Swedish cities with high wind potential from thermodynamic, economic, and environmental aspects to see where it works effectively. The comparative results of various scenarios show that integrating 32 wind turbines, 2 electrolyzers, and 2 reverse osmosis units, with 25% of electricity going to electrolyzers, 20% to reverse osmosis, and 55% to the grid, is the most optimal configuration/allocation. Optimal locations for the power plant are identified in Visby, Halmstad, and Lund due to favorable wind conditions. Setting up the system in Visby could prevent 1878.2 tonnes of CO 2 emissions, generate 93,910 MWh of electricity annually, and create 213 ha of green space. The proposed system in Visby could boast the biggest electricity generation capacity, reaching 11,263 MWh, sufficient to power 938 households. Scaling this model to 12 cities in Sweden could provide the electricity needs of 4500 households, demonstrating the potential for widespread impact. • A novel strategy for peak electricity shaving and wind stability is introduced. • Wind turbines are intelligently integrated with fuel cells to reduce costs. • The system's practicality is compared for various Swedish cities from all facets. • The system in Visby produces 94 GWh of electricity, avoiding 1878 tons of CO 2. • This strategy offers sustainable energy to 4500 homes if scaled up to 12 cities. [ABSTRACT FROM AUTHOR]

Biogas-fueled decentralized energy systems featuring gas turbines emerge as pivotal players in the quest for more adaptable and eco-friendly energy solutions. This study presents the design of a cutting-edge multigeneration system that harnesses the potential of a gas turbine coupled with ejector-driven dual-loop bi-evaporator technology, reverse osmosis desalination, proton exchange membrane electrolysis, and an organic Rankine cycle. The research encompasses an extensive sensitivity analysis and deploys a genetic algorithm-based optimization technique. Through meticulous Optimization, the system achieves remarkable outcomes, including electricity generation, cooling capacity, heating capacity, desalinated water production, and hydrogen yield, measured at 957.3 kW, 231.4 kW, 272.3 kW, 7.336 kg/s, and 0.99 kg/h, respectively. Notably, this performance surpasses the base case by 2% and 8.9%, yielding exergy efficiency and total unit cost improvements of 33.3% and 16.4 $/GJ. Among the critical decisions made was selecting an organic working fluid for the organic Rankine cycle. Through rigorous evaluation, isobutene emerged as the optimal choice, demonstrating significantly improved output power compared to alternatives. Isobutane as the working fluid led to a substantial increase in overall exergy efficiency and a resultant total unit cost of 18.06 $/GJ, accompanied by an impressive 23.48% exergy efficiency. [Display omitted] • Proposing a novel multi heat recovery for a biogas-fed Brayton cycle in five stages. • Using an ejector-based bi-evaporator cycle in integration with a dual-loop ORC. • Comprehensive energy/exergy/cost study and multi-objective optimization. • Comparing different organic fluids in the MCCP leading to selecting isobutene. • Optimum exergy efficiency and total unit products' cost are 33.33% and 16.44 $/GJ. [ABSTRACT FROM AUTHOR]

In the current research, an ocean thermal energy conversion (OTEC) assisted multi-generation process with a transcritical Rankine cycle (tRC) working with carbon dioxide is proposed for green hydrogen, oxygen, and distilled water production. The suggested utilizes thermal energy from the ocean to drive tRC, where the liquefied natural gas (LNG) subsystem acts as the heat sink. The process also comprises an LNG turbine to take advantage of LNG cold energy, a proton exchange membrane electrolyzer (PEM-El) unit for hydrogen and oxygen production, photovoltaic/thermal (PV/T) collectors, and reverse osmosis (RO) desalination unit with a recovery turbine. For the thermodynamic evaluation, a numerical model is engineered for the system, and the evaluation of the system's performance in terms of energy and exergy is conducted. According to the analysis, the total net power obtained from the hybrid system is calculated as 1734 kW, while the overall energy efficiency of the system is found to be 26.3%. In addition, the total exergy destruction is determined as 4859 kW with an exergy efficiency of 35.5%. Furthermore, H 2 and distilled water production rates are estimated as 1.349 kg/h and 10.31 m3/h, respectively. • A novel design for an ocean thermal energy conversion-based combined plant is proposed. • Energetic and exergetic performance of the hybrid system is analyzed. • The overall energy and exergy efficiencies are 26.3% and 35.5%, respectively. • The highest contributor to the irreversibility rate is found to be the condenser with 3265 kW. [ABSTRACT FROM AUTHOR]

This study investigated the potential application of geopolymeric material for the separation of oil-in-water emulsions in wastewater treatment. For the first time, an asymmetric membrane made of geopolymers was developed for this specific separation process. The performances of the geopolymeric membrane in oil separation were compared with those obtained by a commercial ceramic membrane. The study also aimed at exploring the effects of emulsion formulation and emulsion properties (surfactant type and concentration, pH, and zeta potential) and membrane parameters (surface charge and material) on permeate volumetric flux and chemical oxygen demand (COD) rejection. Emulsions were prepared using 3% (w/v) dodecane oil in distilled water, with surfactant concentrations of 1x and 10x critical micelle concentration (CMC) and three surfactants of different nature (Oleth-10, Brij 76, and CTAB) at pH values of 2, 5, and 8. Results showed that for the best operating conditions of the geopolymeric membrane, initial and final permeate flux values of 42 and 26 L h−1 m−2, respectively, were achieved. COD rejection values ranged from 95.0 to 99.4% using the geopolymeric membrane thus indicating a very similar behavior between geopolymeric and ceramic membranes. These findings suggest that geopolymers are promising to produce membranes for oil-in-water emulsion microfiltration, promoting an interesting alternative for the treatment of industrial wastewater more sustainable in terms of environmental effects and costs compared to ceramic membranes. • Novel geopolymeric asymmetric membrane was synthetized. • Geopolymer selective layer was successfully deposited on pressed geopolymer support. • The geopolymeric membrane showed excellent fluxes and removal efficiencies. • Flux and rejection properties vary with surfactant concentration and emulsion pH. • Geopolymer membrane performs similarly to a commercial microfiltration ceramic one. [ABSTRACT FROM AUTHOR]