Cost Of Water Research Articles

Evaluating oomycete pathogen and community responses to chemical- and Slow Sand Filtration-based water treatment strategies to enable water recycling in nursery production systems.

While recycling irrigation water can reduce water use constraints and costs in nurseries, adoption is hindered by the associated risk of recirculating and spreading waterborne pathogens. To enable regional water re-use, this study assessed oomycete re-circulation risks and recycled water treatment efficacy at organismal and community scales. In culture-based analysis of recycled pond water at two Mid-Atlantic nurseries across three years, diverse oomycetes (12+ species) were detected using culture-based analysis, with Phytopythium helicoides as the dominant species; MiSeq analysis detected eight of these species, plus 24 additional taxa. Oomycete contamination risk and detection abilities in recycled water was highest in fall and/or spring based on species richness (P = 0.001). Four species, Pythium oopapillum, Pythium aff. diclinum, Phytophthora cryptogea-complex and Phytopythium helicoides were pathogenic to seedlings (90% damping off) and mature chrysanthemum plants, causing decline in more plants than negative controls (P = 0.025)-these species thus represented the known pathogen targets for recaptured water treatment. Slow Sand Filtration (SSF) of recaptured water resulted in an 85% or greater reduction in oomycete recovery from baits across months, although detection in greenhouse water following treatment indicated re-introduction challenges. MiSeq analysis indicated that SSF altered relative species abundances, which decreased for two species and increased for three species, including one putative pathogen, post-SSF (P < 0.05). Chlorine treatment reduced recovery of oomycetes from baits by at least 75%, although diversity increased, as did relative abundance of several species including one putative pathogen (P < 0.05). Together these results indicate that SSF and chlorination have potential efficacy in enabling irrigation water recycling in nursery production, although system modifications are needed to improve treatment efficacy and prevent pathogen re-introduction post-treatment.

Economic analysis of smallholder dairy cattle farms: Case study of Nandi and Makueni Counties in Kenya

Kenya has the highest annual per capita milk consumption on the African continent (110 litres), and is projected to increase to 130 litres by 2030. This has supported the development of the smallholder dairy production system which supplies 80% of the milk. Dairy farming enhances nutrition and generates income for more than 1.8 million smallholder farmers in Kenya. This study aimed at analysing the economic performance of dairy cattle farms in Nandi and Makueni counties and compare their performances as farms practicing mixed farming and as dairy farming alone, using gross margins. Further, this study sought to determine exogenous variables influencing dairy farms’ economic performance. The study used a mixed research design (quantitative and focus group discussions) with key informants in the dairy sector in the 2 study counties. Purposive sampling was used to select the farms and the county based dairy data gathering and monitoring harmonized profit and loss tool developed by the Kenya Dairy Board (KDB), Kenya Dairy Processors Association (KDPA) and State Department of Livestock was used to collect data. The 2 counties differ in the level of smallholder dairy development. Nandi County was classified as a highly dairy county while Makueni County as a potentially dairy county hence their selection for inclusion in this study. Gross margins were determined for all farms by total cash income less total cash costs, while multivariable regression using Akaike Information Criterion was used to determine exogenous variables influencing gross margin levels. The findings revealed that dairy enterprises alone have positive albeit minimal gross margins while the typical smallholder mixed farming (dairy and other enterprises) result in losses in both study counties. On average, a farm in Nandi and Makueni counties made a profit of Kenya shilling (Ksh.) 2,848.30 and 880.80 per year respectively. Although the differences were not statistically significant (p&gt;0.5) due to high variances, incomes in Ksh. from milk (Nandi: 21,470.3, Makueni: 51,555.3) and manure (Nandi: 7,609.2, Makueni: 605.9); and costs of feed (Nandi: 23,337.0, Makueni: 37,806.4), labour (Nandi: 10,792.9, Makueni: 13,943.4), mineral salts (Nandi: 20.9, Makueni: 33.9), artificial insemination (Nandi: 770.9, Makueni: 996.0), veterinary services(Nandi: 1,541.8, Makueni: 1,991.9), transport (Nandi1:130.0, Makueni:2,062.2) and water (Nandi: 187.6, Makueni: 363.5) were significantly different between Nandi and Makueni counties (p=0.00). Final models with exogenous variables had low prediction of gross margins, R2&lt;0.30. Due to the high costs of dairy farm inputs accounting for 94% and 99% in Nandi and Makueni counties respectively, and the involvement in several farm enterprises at the same time, farmers in both counties risk making losses or getting very minimal profits. Policies focused on making farm inputs especially feed and water affordable and accessible to smallholder dairy cattle farmers are highly recommended.

The sharing practices of utility costs in compound houses in urban Ghana: Examining trust, solidarity and power relations

ABSTRACT Shared housing is a popular housing choice among low- and middle-income individuals in cities worldwide. In Ghana, the compound house, a traditional West African housing typology, presents the most common form of shared housing. While the compound house has been the subject of several past studies, little attention has been given to the sharing practices of utility costs (electricity and water). This article investigates the typologies, experiences and responses of renters to utility cost sharing in urban Ghana. Based on interviews with 35 respondents in compound houses in Asafo, Kumasi, we found that electricity and water costs are primarily shared through gadget-based and point-based systems, respectively. The adoption of these sharing practices is characterized, among others, by renters’ hesitation to declare all their gadgets due to security concerns, restriction on the usage of personal gadgets and instances of delayed or nonpayment of utility costs by certain renters. In response, some renters acquire personal meters to avoid the challenges associated with sharing. Drawing on the concept of social capital, we discuss these findings within the framing of trust, solidarity and power relations in shared housing practices and offer relevant recommendations.

Strategic Dam Locations for Enhanced Management of Water Resources, Cost Savings and Carbon Emission Reduction in the Southwestern Region of Saudi Arabia

Strategic Dam Locations for Enhanced Management of Water Resources, Cost Savings and Carbon Emission Reduction in the Southwestern Region of Saudi Arabia

ДОСЛІДЖЕННЯ ЕКОНОМІЇ ЕНЕРГЕТИЧНИХ І ВОДНИХ РЕСУРСІВ В СИСТЕМІ ВОДОПОСТАЧАННЯ БАГАТОПОВЕРХОВОГО БУДИНКУ ЗА ДВОРІВНЕВИХ СТОЯКІВ

The influence of the structure of the electromechanical water supply system of a 12-story building (replacing one riser with two risers of different levels) on the efficiency of energy and water resource use was studied. A mathematical model of the electromechanical system has been developed and implemented in software, which takes into account the dependence of the floor consumption on the pressure value and allows determining the water needs of consumers based on the given cyclorama of the water consumption of the house. According to the information about the known parameters of the basic version of the water supply system, the parameters of one floor and the parameters of the variants of the building system with risers for servicing floors are determined: 1-12; 1-6; 7-12. The study was carried out taking into account the proposed time dependence of the change in the input pressure of the house. Means of generalized determination of the energy efficiency of the asynchronous motor of the water supply system based on approximate dependences of nominal efficiency on power and efficiency on the degree of loading have been developed. The comparison of options was carried out according to the formulated expression of the efficiency criterion, as the ratio of the daily useful effect of the water supply system to consumers to the cost of electricity and water consumed during the given period. According to the simulation results, the two riser option provides savings of 4% of water and 25% of electricity with their ratio in monetary terms 6:1. This justifies the priority of taking into account water savings when justifying the modernization of water supply systems (parallel zoning, adjustable electric drive). References 11, table 1, figures 3.

Cost-of-illness study among patients with diabetes mellitus and coping mechanisms in Northern Ghana

IntroductionThe increasing prevalence of diabetes globally imposes financial burden on individuals, societies and health systems. However, not much is known about the treatment costs of diabetes and the coping mechanisms...

Generalized Stomatal Optimization of Evolutionary Fitness Proxies for Predicting Plant Gas Exchange Under Drought, Heatwaves, and Elevated CO2.

Stomata control plant water loss and photosynthetic carbon gain. Developing more generalized and accurate stomatal models is essential for earth system models and predicting responses under novel environmental conditions associated with global change. Plant optimality theories offer one promising approach, but most such theories assume that stomatal conductance maximizes photosynthetic net carbon assimilation subject to some cost or constraint of water. We move beyond this approach by developing a new, generalized optimality theory of stomatal conductance, optimizing any non-foliar proxy that requires water and carbon reserves, like growth, survival, and reproduction. We overcome two prior limitations. First, we reconcile the computational efficiency of instantaneous optimization with a more biologically meaningful dynamic feedback optimization over plant lifespans. Second, we incorporate non-steady-state physics in the optimization to account for the temporal changes in the water, carbon, and energy storage within a plant and its environment that occur over the timescales that stomata act, contrary to previous theories. Our optimal stomatal conductance compares well to observations from seedlings, saplings, and mature trees from field and greenhouse experiments. Our model predicts predispositions to mortality during the 2018 European drought and captures realistic responses to environmental cues, including the partial alleviation of heat stress by evaporative cooling and the negative effect of accumulating foliar soluble carbohydrates, promoting closure under elevated CO2. We advance stomatal optimality theory by incorporating generalized evolutionary fitness proxies and enhance its utility without compromising its realism, offering promise for future models to more realistically and accurately predict global carbon and water fluxes.

The hydrogen-water collision: Assessing water and cooling demands for large-scale green hydrogen production in a warming climate

Hydrogen is expected to play a critical role in future energy systems, projected to have an annual demand of 401-660 Mt by 2050. With large-scale green hydrogen projects advancing in water-scarce regions like Australia, Chile, and the Middle East and North Africa, understanding water requirements for large-scale green hydrogen production is crucial. Meeting this future hydrogen demand will necessitate 4,010 to 6,600 GL of demineralised water annually for electrolyser feedwater if dry cooling is employed, or an additional 6,015 to 19,800 GL for cooling water per year if evaporative cooling is employed. Using International Panel of Climate Change 2050 climate projections, this work evaluated the techno-economic implications of dry vs. evaporative cooling for large-scale electrolyser facilities under anticipated higher ambient temperatures. The study quantifies water demands, costs, and potential operational constraints, showing that evaporative cooling is up to 8 times cheaper to implement than dry cooling, meaning that evaporative cooling can be oversized to accommodate increased cooling demand of high temperature events at a lower cost. Furthermore, of the nations analysed herein, Chile emerged as having the lowest cost of hydrogen, owing to the lower projected ambient temperatures and frequency of high temperature events.

Leaf senescence characteristics and economic benefits of rice under alternate wetting and drying irrigation and blended use of polymer-coated and common urea.

Water-saving irrigation and the mixed application of controlled-release nitrogen fertilizer (CRNF) and common urea (CU; with a higher nitrogen release rate) have shown promise in improving rice yield with high resource use efficiency. However, the physiological mechanism underlying this effect remains largely unknown. This study involved a field experiment on rice in Jingzhou City, Central China, in 2020 and 2021. Two irrigation regimes were employed [alternate wetting and drying irrigation (AWD) and conventional flood irrigation (CI)], with three nitrogen (N) compounding modes [00% CU (N1), 60% CRNF + 40% CU (N2), and 100% CRNF (N3)] with an equal N rate of 240kg ha-1. The results indicated a significant interactive effect of watering regimes and N compounding modes on net photosynthetic rate (P n), leaf area index (LAI), and SPAD values; activities of superoxide dismutase (SOD), peroxidases (POD), catalase (CAT), glutamine synthetase (GS), glutamine 2-oxoglutarate amidotransferase (GOGAT), and nitrate reductase (NR); and the contents of malondialdehyde (MDA) and soluble protein in rice leaves. Compared with N1, N2 and N3 increased the P n, LAI, and SPAD values; activities of SOD, POD, CAT, NR, GS, and GOGAT; and soluble protein content but decreased MDA content in the post-growth (heading and maturity) stages by 8.7%-31.2% under the two irrigation regimes. Compared to CI (traditional irrigation), AWD had higher P n, LAI, and SPAD values; activities of SOD, POD, CAT, NR, GS, and GOGAT; and soluble protein content (increased by 12.1%-38.0%, and lower MDA content (reduced by 13.1%-27.6%) irrespective of N compounding modes. This suggested that AWD combined with N2 and N3 could delay the leaf senescence of rice, thus achieving a larger grain yield. Moreover, AWD significantly decreased water costs (irrigation amount) and labor costs (irrigation frequency), thus increasing total income. N2 decreased fertilizer costs with a higher or comparable total income compared with N3. Therefore, the AWDN2 treatment achieved the highest net income (13,907.1 CNY ha-1 in 2020 and 14,085.7 CNY ha-1 in 2021). AWD interacted with 60% CRNF + 40% (N2) to delay leaf senescence by improving photosynthesis, antioxidant defense system, osmoregulation, and N assimilation, contributing to high grain yield and net income in rice.

Sustainable multiphase jet polishing of additively manufactured heat pipes utilizing recycled glass chips

Each year, a huge amount of waste glass chips is produced by machining, which is not recycled and has been treated as waste, resulting in the wasting of resources. However, the pristine physical properties of these micro-sized chips show great potential to be recycled as abrasives in jet polishing. In this work, machined glass chips were recycled and directly used as the abrasives in multiphase jet (MPJ) and abrasive water jet (AWJ) polishing for aluminum heat pipes of additive manufacturing with complex structures. Polishing performance of the recycled abrasives from waste glass was compared with those of commercial quartz abrasives with mesh sizes of 600, 800, 1000, 1200, and 3000. The results show that the recycled abrasives of glass chips have comparable performance to the commercial abrasives with mesh size of 1000. Computational fluid dynamic simulations were conducted on the two jet polishing to elucidate the fundamental material removal mechanisms. It is found that a higher drag force in the AWJ polishing could lead to uniform material removal and induce four times higher for material removal rate (MRR). The cost of setup, water and energy consumptions of MPJ polishing are only one tenth those of AWJ polishing. Energy dispersive spectroscopy reveals that there is no element contamination on the polished surface. This work proposes a novel approach of MPJ polishing for components produced by additive manufacturing with complicated structures. These findings provide new insights for the recycling use of waste chips generated in manufacturing, and suggest new solutions for saving energy and resources, as well as for clean and green production.

4E Analysis of Productivity and Efficiency Enhancements in Pyramid Solar Distillation: Innovations in Tray Design, Water Heating, and Forced Condensation Integration

This research enhances the thermal efficiency of a pyramid solar distiller (PSD) through 4E (energy, exergy, economic, and environmental) analysis. The modified distiller (MPSD) features suspended trays on three vertical walls, tested with and without heaters, and various water levels (6.2 to 49.6 L) in the basin. The study also examined MPSD's performance with an external condenser, aided by a fan operating at different speeds (0.25 to 1.5 rpm). Results showed that the MPSD, with a water depth of 1 cm and 12.4 L in the basin, achieved a 33% yield improvement and 50.2% efficiency. Total productivity of MPSD reached 3755 mL/m2 compared to 2820 mL/m2 for the PSD. MPSD with heaters produced 6430 mL/m2, reflecting a 98.5% increase. The best performance occurred at 1.25 rpm, with a 133% productivity increase, 66.5% thermal efficiency, and 4.58% exergy efficiency. The water cost was $0.23/L for the MPSD, lower than the PSD's $0.34/L. CO₂ emissions were 30.93 to 32.23 tons per year for different configurations, and enviroeconomic indicators were 447.46 to 467.33 annually, depending on the setup.

Using electromagnetic induction to inform precision turfgrass management strategies in sand‐capped golf course fairways

AbstractTo meet the turfgrass standards that players expect, golf course superintendents rely on intense irrigation, fertilization, and cultivation programs. However, the overapplication of irrigation water and fertilizer has been shown to have negative effects on water quality. Precision turfgrass management (PTM) is an emerging area of interest as more golf course superintendents are looking to increase input efficiency while simultaneously reducing water and fertilizer input costs, as well as environmental impacts. Our objectives were to (1) use electromagnetic induction (EMI) to determine the spatial variability of apparent electrical conductivity (EC) in sand‐capped fairways and (2) correlate EC to measured soil and turfgrass characteristics to determine the applicability of mapping EC for PTM. Soil samples and EC data were collected in spring 2021 on four sand‐capped fairways from two golf courses (one hybrid bermudagrass and one zoysiagrass) belonging to the same facility in southeast Texas. Apparent EC was found to be positively and significantly correlated with soil volumetric water content (VWC, 0.40 &lt; r &gt; 0.62) and turfgrass normalized difference vegetation index (NDVI; 0.21 &lt; r &gt; 0.46) in three of four fairways, while EC was negatively and significantly correlated with penetration resistance (PR, −0.29 &lt; r &gt; −0.48) in two of four fairways studied. The strengths of these relationships were corroborated by strong visual similarities when comparing spatial maps of EC with those of VWC, NDVI, and PR, indicating that EMI‐based EC data have potential for use in delineating site‐specific management zones for water and fertilizer applications, as well as targeted aeration.

Using process modeling and simulation to determine the sustainability of a novel lactic acid biorefinery in Europe: Influence of process improvements, scale, energy source, and market conditions

The biorefinery concept aims to produce multiple high-value products from bio-based feedstocks. One such product is lactic acid, which is used across several industries such as food, pharmaceuticals, cosmetics, and chemicals. Lactic acid yield is influenced by several factors, and improvements in performance are often first demonstrated at lab-scale, requiring prospective models which make assumptions about how the system will be optimized to understand the potential of a commercial-scale plant. This study assesses the economic and environmental sustainability of a proposed lactic acid biorefinery through the combination of process modelling, techno-economic assessment, and life cycle assessment. The case study proposes producing high purity lactic acid from industrial candy waste and liquid digestate in Denmark through lactic acid fermentation and downstream membrane separations. A base case is first modelled to determine the economic and environmental hotspots of the system; scenarios are then modelled where improvement methods are implemented reducing consumption of energy, chemicals, water, and the production of waste, upscaling the system, and integrating bioenergy. Finally, a cost sensitivity analysis is run varying bioenergy, water, chemical, and labor costs based on the European market. By optimizing unit processes, scale, energy sources and market conditions, the lactic acid unit production cost and global warming potential can be lowered by 94% and 80% compared to the base case, respectively. However, these are optimized in different scenarios, indicating a trade-off in optimizing economic and environmental criteria. As even best-case lactic acid unit production cost is found to be 141–232% higher than market price, this production pathway will require further improvement or market changes before it can be commercially viable.

Active and Durable Platinum Group Metal-Free Electrocatalysts for Hydrogen Evolution Reaction in Alkaline Systems

Net-zero emission energy technologies are urgently needed to mitigate climate change. Generation of “green” hydrogen via low-temperature water electrolysis using renewable electricity and its utilization in fuel cells for power generation when needed is a highly promising path towards achieving zero emission of greenhouse gases [1]. To guarantee the market affordability of low temperature water electrolyzers, cost and performance targets must be met [1]. The need for expensive catalysts based on platinum group metals (PGMs) in proton exchange membrane water electrolyzers (PEMWE) is currently the main obstacle to their widespread deployment. At the same time, liquid alkaline water electrolyzers (LAWE) exhibit the advantage of operation using catalysts based on earth abundant-based elements [2]. The main drawback of LAWE is the use of strongly alkaline and thus corrosive electrolyte (20-40% KOH), which negatively impacts the catalyst durability. The latter limitation comes on top of low current-density operation and losses in the catalyst performance often occurring as a result of current reversal during shut down [3].Ni-based catalysts, e.g., binary Ni-Mo based materials, display the most promising activity in hydrogen evolution reaction (HER) among non-PGM materials [4]. However, their durability is still a major concern [5]. In one approach, tailoring the design and altering the electronic structure of the NiMo catalysts is an effective route to achieve a higher durability [6].In this work, we designed a novel and facile synthesis approach to developing binder-free Ni-Mo- phosphide electrocatalysts (Ni-Mo-P) in two steps. In the first step, Ni and Mo were deposited on a Ni-foam substrate from a solution containing complexes of the two metals. In the second step, the deposit was phosphidated via reactive annealing in a presence of phosphorus precursor. The formation of NiMo-phosphide was confirmed by XRD. The thus-synthetized catalysts were electrochemically characterized in a three-electrode cell set-up, showing a decent HER activity. The durability of the catalyst was then assessed for 100 h in 1 M KOH solution under constant current operation, with no activity loss detected. We will compare performance of our catalysts with that of the commercially available Ni and Ni-Mo HER electrocatalysts.

Optimal Solar‐Biomass‐Diesel‐Generator Hybrid Energy for Water Pumping System Considering Demand Response

ABSTRACTThe water pumping system is a vital daily operation for a sustainable society. The demand for this essential commodity is progressively growing around the world. Incorporating renewable energy sources (RES) into its operation mitigates adverse environmental effects stemming from greenhouse gas (GHG) emissions and reduces associated costs linked to fossil fuel energy sources. Hence, the optimal sizing of a hybrid mix of RES and non‐RES energy sources to power water pumping is essential. This study employs a generalized reduced gradient (GRG) optimization method to ascertain the most effective energy mix for water pumping system (WPS) application by integrating time of use demand response. This is achieved through four scenarios: Scenario 1 (S1) utilizes grid power and Diesel generator (DG) energy sources, Scenario 2 (S2) incorporates grid power, DG, and solar PV, Scenario 3 (S3) integrates grid power, DG, solar PV, and biomass energy sources, while Scenario 4 (S4) incorporates Time of Use (TOU) with the three aforementioned energy sources. The key findings reveal an ideal solution comprising of a mix of renewable PV and biomass along with non‐renewable grid energy source embedded with Time of Use demand response (S4) with optimal energy capacities of 4007 kW of PV, 4228 kW of grid, 234 kW of biomass, and 1085 of DG owing to the least cost energy and cost of water pumped of 0.75$/kW and 1.74$/kL, respectively, most volume of water pumped of 270.50 kL. These findings prove that the integration TOU demand response program with a hybrid mix of grid‐biomass‐DG‐solar PV is best suited for water pumping applications as it gives a cost‐competitive value.

Using Tap Water for Enteral Tube Flushes.

Enteral feeding tubes, used in patients who require enteral nutrition or medication, require flushing between medications and feedings to maintain patency. Various types of water can be used to flush enteral feeding tubes, which raises the question of which type of water is best supported by evidence. The aims of this quality improvement project were to examine the evidence on the use of tap water instead of sterile water for enteral tube flushes and to implement the use of tap water as a safe, cost-effective alternative to sterile water at a multisite oncology institution. A systematic literature search of electronic databases including Scopus, PubMed, CINAHL, Google Scholar, Embase, and JBI was conducted to review current evidence and professional organization recommendations on the use of sterile water versus tap water in enteral feeding tubes. The oncology institution's policies were reviewed, and nurses were surveyed on the type of water they used for enteral tube flushes. After the literature search and nurse survey results concurred that tap water was as effective as sterile water, the institution's nursing practice policy was updated to state that tap water should be used for enteral tube flushes, and that the use of sterile water for this purpose should be reserved for cases when there are concerns about tap water safety. This policy change was projected to incur annual sterile water cost savings of $15,930 to $19,872. The implementation of a policy recommending the use of tap water for enteral tube flushes standardized clinical practice and decreased institutional costs while maintaining patient safety.

Feasibility studies of green hydrogen production using photovoltaic systems in Iran's southern coastal regions

This study investigates the production of green hydrogen in the southern coastal cities of Iran, leveraging local advantages. These include the high potential for photovoltaic generation, the need for desalination power plants, and access to the sea and ports, all of which make the southern coasts of Iran favorable for green hydrogen production. However, the approach presented in this paper can also be applied to similar regions.Initially, the optimal size of the electrolyzer for maximum hydrogen production at each location is determined. To compare the potential of these locations, the levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) are calculated, and the effects of variables such as the discount rate and water price on these costs are analyzed. Unlike many existing studies, this research accurately models the impact of temperature on the techno-economic outputs of the photovoltaic power plant and electrolyzer and compares it to a scenario where the temperature effect is not considered. Additionally, the study examines the minimum power required for the electrolyzer to operate efficiently, avoiding low-efficiency operations.The results indicate that ignoring the temperature effect leads to an overestimation of electrolyzer power and hydrogen production. The discount rate significantly impacts LCOE and LCOH, while the cost of water for hydrogen production has a negligible effect on LCOH. This is due to the higher influence of energy costs and electrolyzer investment on LCOH.

The Role of Community-Based Initiatives in Enhancing Water Quality and Livelihoods in Rural Tanzania: A Case Study of Mvomero Distric

This study investigates the impact of community initiatives on water quality and household livelihoods in Mvomero District, Tanzania. With a focus on the FuatiliaMaji project. The studyexplores how these initiatives influence both water quality and the socio-economic well-being of households. Using a cross-sectional research design, data were collected from 130 households through structured questionnaires. The analysis revealed that community-based monitoring, water conservation efforts, and the protection of water sources positively contribute to improved water quality. Moreover, these initiatives were found to enhance household income, health, and overall livelihood, although challenges related to water cost and time spent fetching water persist. The study highlights the importance of affordable water solutions and strengthened community participation in water governance to foster sustainable water management practices. The findings suggest that increasing investments in water infrastructure, scaling up community-based monitoring systems, and reducing the economic and time burdens of water collection are crucial for improving both water quality and household livelihoods in the region.

Performance enhancement in air gap membrane distillation using heat recovery configurations

Experimental investigations were conducted on an air gap membrane distillation (AGMD) unit to evaluate the impact of heat recovery on system performance. The study utilized a steady-state heat source in conjunction with a spiral air gap membrane module for water desalination. The process was implemented using two configurations aimed to minimize heat loss enhancing productivity, gain output ratio (GOR), and thermal efficiency. The experiments involved feedwater with salt concentrations ranging from 10,000 to 30,000 ppm. The measurements were recorded for inlet and outlet temperatures of the heat source, water productivity, and thermal efficiency at various coolant and water feed flow rates. These configurations effectively addressed critical technical challenges in thermal AGMD systems by optimizing heat recovery. The incorporation of heat recovery resulted in a significant increase in water productivity by 37.07 % compared to systems without heat recovery while maintaining the same initial heat input. The heat recovery in series (HRSS) and parallel (HRPS) configurations resulted in power consumption reductions of approximately 29.7 % and 23.1 %, respectively compared to the conventional configuration (CC) at a flow rate of 12 L/min. The levelized cost of water (LCOW) for the AGMD system was comprehensively evaluated and found to be $ 7.71 per cubic meter. This figure reflected the total cost of water production over the system's operational lifespan including capital expenditures, operating and maintenance costs, and energy consumption. The calculated LCOW provides a clear indicator of the system's economic viability, demonstrating the cost required to produce each cubic meter of water through the AGMD.

Microplastics removal from a hospital laundry wastewater combining ceramic membranes and a photocatalytic membrane reactor: Fouling mitigation, water reuse, and cost estimation

The release of microplastics (MPs) through industrial laundry wastewater accounts for 35 % of global MPs emissions into the environment and it is a significant environmental problem, especially because MPs can absorb contaminants of emerging concern (CECs) from garments. This study is the first to evaluate and perform a cost estimation of the MP removal from hospital laundry wastewater (HLWW) using a combination of ceramic membranes and a pilot-scale photocatalytic membrane reactor (PMR) as a fouling mitigation strategy. The HLWW, from a hospital in Copenhagen, Denmark, contained a total organic carbon (TOC) of 345 mg L⁻1 and 1.4 × 106 MP L−1, mainly of polyethylene terephthalate (PET) ranging between 100 and 200 μm in size. The pre-treatment with an ultrafiltration (UF) ZrO₂ membrane successfully removed 96 % of MPs and over 98 % of suspended solids and turbidity at an estimated cost of 0.45 US$ per m3 of permeate. In the PMR stage, ultraviolet light emitting diodes (UV LED) irradiation reduced irreversible fouling, improving permeate flow and minimizing the need for chemical cleaning. The Ce–Y–ZrO2/TiO2 photocatalytic membrane achieved over 99 % removal of turbidity, colour, and suspended solids, as well as 99.9 % removal of MPs, allowing the potential effluent reuse within the hospital laundry. Additionally, the retentate from the PMR process had lower TOC, easing the discharge of this concentrated stream. The cost estimation demonstrated that the photocatalytic degradation combined with traditional techniques, i.e. backflush and chemical cleaning, is more economical than using these techniques separately. Therefore, the total treatment cost was 1.09 US$ per m3 of permeate, which is lower than the cost of fresh water in Denmark. In conclusion, this innovative treatment strategy offers a sustainable and cost-effective solution for HLWW management, not only reducing water consumption by enabling water reuse in the hospital laundry but also advances towards achieving net-zero liquid discharge and contributing to the UN Sustainable Development Goals for clean water (Goal 6) and climate action (Goal 13).