Borg El-Arab City Research Articles

Adsorption of Oil from Industrial Wastewater with Eucalyptus globulus Labill. Bark: Optimization Study

Oily wastewater is one of the most hazardous contaminants that can hurt the ecosystem. There is an urgent need to adopt an efficient, eco-friendly, and low-cost material to replace the old traditional treatment methods of oily wastewater that were very expensive in addition to their relatively low efficiency. Eucalyptus bark is considered one of the materials that are rarely used in this field, although it has the characteristics that qualify it to be a distinguished and promising one. The optimum conditions of using Eucalyptus globulus Labill. (Blue gum) bark in the removal of oil from prepared aqueous solutions were concluded before applying in the treatment of real oily industrial wastewater from New Borg El-Arab City, Egypt. The sequential optimization adsorption results were as follows: initial oil concentration, 500 mg/l; adsorbent dosage, 0.5 g/l; pH, 3; exposure time, 45 min; temperature, 20 °C; and shaking rate, 300 rpm. The pretreatment of biomass with H3PO4 proved it to be superior in the oil removal process where the efficacy reached 450.69 mg/g, while the unmodified form came second where the adsorption efficacy reached 395.86 mg/g, after that the NaOH-modified form came third by efficacy reached 315.85 mg/g. The results of SEM elucidated this order of efficacy according to the porosity of the bark surface. FTIR analysis indicated that OH, carboxylic C = O, and carboxylic C-O groups are the contributing groups in the oil adsorption process for the three forms of Eucalyptus bark. The reusability of Eucalyptus bark using n-hexane for one cycle reached 96.34, 97.13, and 95.83% for unmodified, H-modified, and OH-modified forms, respectively, and for five cycles reached 56.29, 58.01, and 55.81% for unmodified, H-modified, and OH-modified forms, respectively. The application of Eucalyptus bark in the H-form in the treatment of real oily wastewater was achieved by efficacy ranging between 91.46 and 96.23% which proves the excellence of Eucalyptus bark in the treatment of oily wastewater.

Biosorptive removal of fluoride from wastewater using tea domestic waste biochar

AbstractThe biochar of tea domestic waste was applied to eliminate F− from their aqueous artificial solutions and real contaminated wastewater. Pre-pyrolysis chemical activation method was used to synthesize biochar from tea domestic waste. Two modification methods were applied, acidic modification using H3PO4 (H-modified form) and basic modification using NaOH (OH-modified form). The synthesized forms of tea biochars were characterized by the determination of ash content, bulk density, Brunauer–Emmett–Teller analyses to detect the pore size, specific surface area, and pore volume, Elemental analyses to detect C, H, O, and N contents, Thermogravimetric analyses to detect the thermal behavior of biochars, and Fourier Transform Infrared analyses to detect the functional active groups of biochars. The synthesized forms of tea biochars were optimized for fluoride removal from aqueous solutions via filter bags method and applied in enhancement of the quality of wastewater from the factories of the new Borg El-Arab City, Egypt. The highest biosorption efficacy achieved was 109.18 mg F−/g biochar using the H-modified form under the optimum conditions of biochar dosage: pH: 2, 0.25 g/l, temperature: 50 °C, initial concentration of F−: 500 mg/l, exposure time: 30 min, and agitation rate: 300 rpm. The OH-modified form achieved less than half biosorption efficacy which reached 49.39 mg F−/g biochar. The existence of competitive anions in the solution had a negative influence on F− biosorption efficacy, where the impact followed the order of PO43− > SO42− > Cl− > NO3− > HCO3−. The H-modified tea biochar proved to be a promising biosorbent for industrial wastewater treatment by achieving removal efficacy ranges of 80.89–93.31% and returning all violated F− concentrations to the allowable limit. Sustainable development can be greatly supported by using domestic tea wastes in the removal of F− due to the dual disposal of waste and contaminants at the same time. The tea wastes are eco-safe and cheap biosorbent material can be utilized as a precursor for an efficacious tool for the elimination of F− from artificial solutions in addition to real wastewater.

Environmental impacts of industrial activities on floral coverage with special emphasis on detoxification enzyme activities in Cataglyphis savignyi as pollution biomarker

The present study investigates the environmental impact of industrial activities on floral coverage within the major industrial district of Borg El-Arab City, Egypt. Additionally, it aims to evaluate the detoxification enzymatic activity of Cataglyphis savignyi as a pollution biomarker. To achieve this objective, seasonal soil samples were collected from the studied sites to determine soil properties and heavy metal concentrations. Furthermore, a seasonal specimen of C. savignyi was collected to study the enzymatic activity of acetylcholinesterase (AChE) and glutathione-S-transferase (GST). Heavy metal contamination pollution indices were calculated, and fourteen plant species were identified at the investigated sites for four successive seasons from 2020 to 2021. The soil physicochemical parameters significantly varied in the industrial sites compared to the control site. The accumulation of heavy metal contamination in soil for investigated sites followed the order Ni > As > Pb > Hg. Calculated Cdeg and PLI for industrial 3 revealed a very high degree of contamination, attributed to increased industrial activity from the chemical and silicate factories that characterize this region. The current results highlight the inhibition of GST levels in C. savignyi at the industrial site compared to the control site. In contrast, AChE increases, which might be due to heavy metals enhancing acetylcholine activity at synapses. Consequently, the antioxidant enzymatic activities are useful as biomarkers for assessing and monitoring environmental contamination. In conclusion, this study underscores insects as potent biomarkers for heavy metal contamination, marking a significant advancement in environmental monitoring. These bioindicators offer crucial insights into the impacts of climate change and industrial pollution. The research reveals distinct plant diversity variations and higher heavy metal content in industrial sites, indicating pronounced contamination. Additionally, the study highlights altered enzyme activities in insects, emphasizing their utility as biomarkers for assessing environmental contamination. This work represents a substantial leap forward in comprehending the complex dynamics between contamination and ecological balance.

Early energy assessment at the neighborhood level to promote greater energy efficiency. The case of Nabta Smart Town in Egypt

The potential for an early energy assessment to further improve neighborhood/precinct planning and promote greater energy efficiency is considerable, as confirmed by numerous studies around the world and corroborated by the authors’ experience. Egypt is certainly no exception and in recent years there is growing research evidence to this effect. However, more knowledge is needed on how to develop affordable and locally viable solutions that are integrated into the urban planning process from the outset. This article discusses the results of the “Energy Efficiency Feasibility Assessment of the Master Plan of Nabta Smart Town (NST)”, an “education town” under planning in New Borg el Arab City (NBC), close to Alexandria. The results show how an early energy assessment, carried out as early as the planning stage, which considers local regulations and specific conditions, can help achieve considerable energy efficiency in the future by identifying affordable, evidence-based, and locally feasible solutions that can be further optimized at the design stage. Therefore, the value of this study is not in proposing a new standard solution for everyone, but in showing through an application example how the potential of an early energy assessment at the neighborhood/precinct level can be realized in practice. The immediate benefit is in promoting greater energy efficiency through the design and optimization of renewable energies and passive solutions. This achievement can in turn be used to rethink the planning and decision-making process in the local context. The greatest impact is not only in the selected case study, but in its potential for replicability throughout the Global South.

Energy audit, techno-economic, and environmental assessment of integrating solar technologies for energy management in a university residential building: A case study

This study presents the results of an energy audit and management performed on a university residential building in Borg El-Arab City, Egypt. The building’s energy consumption, areas of energy wastage, and energy-saving opportunities were investigated, and the corresponding energy metrics were quantified accordingly. Firstly, an energy consumption is estimated based on the building's electricity bills, meter measurements, and survey. Then, the energy consumption is analyzed and evaluated. Subsequently, the feasibility of integrating solar technologies (i.e., photovoltaics and domestic water heating) into buildings is appraised from techno-economic and environmental perspectives. The study employs ASHRAE Level 1 and 2 guidelines for conducting energy audits. The results show that electricity consumption is highest in air conditioning units (which consume ∼62%), followed by socket loads (∼25%), and lastly, lights (∼13%). Detailed analysis of the energy-use characteristics of the building revealed the mismanagement of electricity. Through light retrofits such as replacing the incandescent bulbs with LED bulbs, adopting sensory lights, and delamping, the building would save 4,432.6 kWh annually. Additionally, changing the AC unit type from non-inverter to inverter type would save approximately 61,194 kWh/year, representing 22.96% energy savings, with a payback period of 8.6 years. Overall, the proposed energy conservation measures will mitigate 30.8 tons of CO2 per year. Furthermore, incorporating PV and SWH systems will lead to annual energy contributions of 79,820 kWh and 38,048 kWh, with payback periods of 3.77 years and 2.49 years, respectively. Notably, the solar technologies will altogether abate approximately 91.5 tons of CO2 and provide a carbon credit gain of $1,830 annually.

Assessment of standalone streetlighting energy storage systems based on hydrogen of hybrid PV/electrolyzer/fuel cell/ desalination and PV/batteries

Expanding the scope of renewable energy consumption is essential to achieve the aim of a sustainable and carbon neutrality society. Hydrogen could be considered the future form of the leading energy system for multipurpose applications. In the current study, the performance of a standalone streetlighting photovoltaic hydrogen storage system (PV/H2) via hybrid polymer electrolyte membrane/fuel cell/single effect desalination system (PV/PEM/FC/SED) is investigated and compared with the traditional (PV/Battery) system. A complete mathematical model of the two systems is constructed. A MATLAB/Simulink code is developed to simulate both systems under the actual climatic conditions of New Borg El-Arab City, Egypt. The results indicate that the yearly load is 19,745 kWh, which can be fulfilled with 160 m2 of PV panels in the case of PV/H2 and 40 m2 for the PV/Battery system. In addition, the overall system efficiency is 8.5 % and 17.8 % for the hydrogen and battery system, respectively. Although the battery system is more efficient than the hydrogen system, the latter is more economical. The Levelized cost of electricity for the PV/H2 is 1.06 $/kWh with a payback period of 6.44 years compared with 2.8 $/kWh and 11.7 years for PV/Battery systems. Therefore, the hydrogen system is recommended for supplying electricity demand. The system reduces CO2 emissions by up to 25.6 Tons per year with up to 1024$ annual gain.

Groundwater Investigation Using Electrical Resistivity Method at New Borg El-Arab City, Alexandria, Egypt

New Borg El-Arab is a city located on the northwestern coast of Egypt, where the increasing anthropogenic activities have led to an increase in water demand. Groundwater is the main source of water in this area, but it is seriously affected by the Mediterranean saltwater intrusion. This causes a substantial impact on the water quality of the coastal aquifer. In this study, the electrical resistivity method was applied to delineate the shallow groundwater aquifer and its quality. Twenty vertical electrical soundings (VES) distributed along 6 profiles were measured. To observe the seasonal groundwater variations, 14 VES points were measured at the end of the rainy season, while the measurements of 6 VES points were repeated at the end of the dry season. The results revealed 4 geoelectrical layers; the first layer is a surface dry zone with variable resistivity values, followed by a water-bearing layer; while the third is a limestone layer, followed by a clay deposits zone. In comparison to the winter season, the water-bearing layer records lower resistivity values at the end of summer. Optimal locations to drill new groundwater wells have also been determined with a depth varying from 1.8 m north to about 30 m south.

Energy audit and management of an industrial site based on energy efficiency, economic, and environmental analysis

This study presents an energy audit and management for an industrial site in Borg El-Arab City, Egypt. Notably, the investigated industrial site falls in the category of small and medium-sized enterprises (SMEs), which are characterized by a high share of final energy use and possess a significant untapped energy-efficiency potential. In this work, potential sources of energy wastage in the facility have been investigated following a unique energy audit and analysis road map. Furthermore, tailored energy efficiency recommendations and effective energy management practices have been proffered for the various industrial equipment available for the first time. Besides, the proposed action plans are economically evaluated using the payback method and their environmental benefits are assessed accordingly. The results show that a proposed expansion of the PV system would produce 676.62 MWh/year and satisfy about 50.95 % of the factory’s annual electricity consumption. The renewable energy system presents an investment cost of $124,115 with an attractive payback period of about 3 years alongside curbing 293 tons of CO2 emissions annually. In addition, the installation of variable speed drives in the motor systems would save about 48.477 MWh/year with a payback period of 1.73 years and mitigate about 21 t of CO2 annually. Nevertheless, thermal insulation of the mold assembly using thermal boards and incorporating an air gap in the mold assembly design results in energy savings of about 319 MWh per year. The energy management of fans, compressors, and lights demonstrates annual energy savings of 121.461 MWh, 14.88 MWh, and 32.154 MWh, respectively. Notwithstanding, replacing fossil fuel-based forklifts with electric forklifts leads to an investment cost of $32,220 with an associated payback period of 5.74 years. Noteworthy, the energy audit and management herein present energy savings and CO2 emissions mitigations of 535.971 MWh and 232 t annually, respectively. Evidently, the energy audit and management performed will act as a guide for relevant decision-makers towards energy efficiency improvements, consequently achieving economic savings and limiting the carbon footprint.

Towards Resilience: Energy Efficiency in Urban Communities - Case study of New Borg El Arab City in Alexandria, Egypt

Energy demands is one of the most important challenges for the future of urban communities and its built environment. Hence, the resilience of energy in urban communities is one of the effective concepts used to face the energy crisis fact due to the intensive consumption of energy. In this context, the paper is concerned with reviewing the previous literature for urban energy. resilience principles and energy-built environment frameworks by specialized international organizations and also studying the experiences of two top ranked international resilient cities. This paper proposes an energy resilient built environment conceptual framework in order to better recognize and examine the complicated problems of resilient and energy efficient urban communities. An analytical approach was applied for the current situation of New Borg El Arab City in Alexandria, Egypt using the proposed framework for measuring the resiliency level in the built environment, then applying an AHP method for determining the priorities of its built environment components, which need to be developed in order to achieve a resilient city. Thus, the overall goal is to provide a model to city planners and decision-makers that could enable them to plan for adaptable urban communities to be more resilient towards energy vulnerability.

Energy management of standalone cascaded adsorption-compression refrigeration system using hybrid biomass-solar-wind energies

This study examines the energetic and economic feasibility of a new hybrid renewable biomass-solar-wind energy system for driving both cascaded adsorption-compression refrigeration systems compared with its counterpart conventional compression system for the same input energy. Two renewable energy scenarios are proposed: biomass-solar-battery (Scenario-I) and biomass-solar-wind-battery system (Scenario-II) for autonomously driving the cascaded adsorption-compression system. Herein, biomass and thermal waste heat from photovoltaic/thermal collectors are exploited for the adsorption system’s operation. By contrast, the compression unit is propelled by the electric power of the photovoltaic/thermal collectors besides wind energy. In that respect, surplus electricity beyond the battery bank’s charging is converted into heat through an electric heater. These scenarios are investigated and compared using representative meteorological data of New Borg El-Arab city, Egypt. The results demonstrate that Scenario-I is more cost-effective than Scenario-II, which has a cost of refrigeration of 0.235 $ kWh−1 compared to 0.237 $ kWh−1 of Scenario-II. Herein, photovoltaic/thermal collectors in Scenario-I ultimately deliver 100% of the required electric load beside excess electricity of 16.6 kWh. Comparably, Scenario-II delivers surplus electricity of 15 kWh due to the designed fewer numbers of photovoltaic/thermal collectors. Whereas biomass energy covers most of the requisite thermal demand for both scenarios. Moreover, a trade-off between the proposed cascaded adsorption-compression cycle and the renewable-based conventional compression cycle has been conducted. Herein, two proposed systems of photovoltaic-battery (Scenario-III) and photovoltaic-wind-battery (Scenario-IV) are proposed for the conventional compression cycle. The results exhibit that Scenario-III would attain a minimum annual cost of $2714 compared to $4045 for the cascaded system, notably in Scenario-I. In general, using renewable energy mix to drive cooling/refrigeration systems could pave the way towards abating ongoing energy demands and undermining global warming and climate change impacts.

Effects of Using Green Concrete Materials on the CO2 Emissions of the Residential Building Sector in Egypt

Increasing the rate of construction material consumption has caused significant environmental problems in recent decades, especially the production of ordinary Portland cement (OPC), which has been associated with 8% of the world’s human CO2 emissions and is considered the leading binder of concrete. This study aims to investigate the effects of substituting conventional concrete (CC) material with green concrete (GC) in the non-structural concrete works of a residential building in New Borg El-Arab City, Egypt. It attempts to establish what the effects are of using GC on cement, natural aggregates, and CO2 emissions in the design phase. By using a design-based solution (DBS), we began with redesign, reduce, reselect, reuse, and recycle strategies to find an optimal solution for applying recycle aggregate concrete (RAC) as a replacement material in selected building parts, such as the internal floor, external sidewalk, entrance steps, and wall boundary. AutoCAD software and 3Dmax were used to modify the original design and obtain two design references with four different scenarios. Comparative analyses were applied to investigate the effects of different concrete materials. The results show a reduction of about 19.4% in cement consumption in terms of the total concrete of the building and a 44.5% reduction in CO2 emissions due to the reduction of cement in specific building parts. In addition, this solution decreased natural coarse aggregate (NCA) consumption by 23.7% in the final concrete. This study recommends that GC materials close the loop of cementitious material consumption to reduce environmental impacts and achieve sustainability in the Egyptian building sector.

Expression of immune-related genes in parasite-infected Tilapia nilotica (Oreochromis niloticus) from Egypt and molecular characterization of the parasites

Aquaculture is one of the world's most rapidly developing animal production sectors. Tilapia nilotica (Oreochromis niloticus) is the most popular fish known for quality and price. In the present study sixty fish samples of Tilapia nilotica (Oreochromis niloticus) of about 16-22cm length were collected from Tilapia breeding farms and twenty Nile tilapia fish samples were collected for tissue sampling rom each farm. Fish samples were thoroughly investigated for external parasites by visual inspection microscopically through fixed wet smears from the gills and skin. The DNA was extracted from the fish and 17 different parasite species were amplified for partial 18S rDNA and entire ITS1 regions using three sets of commonly recommended primers. The amplicons were confirmed through sequencing. The results exhibited that Trichodina sp. and Gyrodactylus hildae in gills, Cichlidogyrus aegypticus on skin while Acanthosentis sp. was found in the intestine of infected tilapia within Fuwa City, Kafr El sheikh Governorate. The parasites found in Mataria City, Dakahlia Governorate were Cichidogyrus halli on the gills, Zschokkella candia on muscles, and Clinostomum tilapiae in the intestine. The parasites Dactylogyrus sp. and Myxobolus fomenai were recovered from the skin and muscles, respectively, of infected Tilapia from King Mariout, Borg El-Arab City, Alexandria Governorate. Moreover, the expression level of IL-1β gene was up-regulated in muscle, skin, gills and intestine tissues of fish infected with parasites such as Z. candia, C. halli, C. tilapiae, Dactylogyrus sp., M. fomenai, C. aegypticus, Trichodina sp., G. hildae, and Acanthocentis. The similar up-regulation tissues expression trends of TNF-α and IFN-γ genes were found in fish infested with these parasites. The present study exlored molecular characterization of different parasites isolated in different locations of Egypt in Tilapia nilotica (Oreochromis niloticus) and up-regulation of the inflammatory response genes such as IL-1β, TNF-α and IFN-γ is an indicator of the sever inflammation due to these parasitic infestation in fish.

Remediation of ammonia-stripped sanitary landfill leachate by integrated heterogeneous Fenton process and aerobic biological methods

ABSTRACT The use of heterogeneous Fenton process combined with biological and physical treatment of sanitary landfill leachate has been evaluated. Leachate used in this study was collected from the drainage system of a landfill in Borg El-Arab city – Egypt. As a pre-treatment step, the collected leachate was subjected to ammonia stripping at pH 10.0 for 6 h to reduce the ammonia toxicity for the subsequent biological treatment steps. In this step, over 80% of the ammonia content of the leachate could be removed. Then, the ammonia-stripped leachate was subjected to heterogeneous Fenton process or to aerobic biological treatment. At its optimum operating conditions namely; 37.18 g/L H2O2, 5 g/L catalyst and a reaction time of 4 h, the use of heterogeneous Fenton process achieved COD removal up to 73%. Corresponding COD removal obtained after biological treatment was 68%. To select the best sequence of the treatment steps, the ammonia-stripped sanitary landfill leachate was subjected to two treatment trains. The first one was biological treatment followed by heterogeneous Fenton process; while, the second was heterogeneous Fenton process followed by biological treatment. The highest reductions of the organic compounds and ammonia were achieved after using biological treatment followed by the heterogeneous Fenton process. The use of this treatment configuration achieved total COD, BOD and NH4-N removals of 88%, 84% and 96% respectively. Accordingly, the proposed treatment train can be considered effective in the treatment of landfill leachate and environmental protection.

Evaluation of Partial Nitritation/Anammox Process for Reduction of Pollutants from Sanitary Landfill Leachate

A proposed combined process (partial nitritation process followed by anaerobic ammonia oxidation process (anammox)) was used to treat municipal landfill leachate with high amount of pollutants. This process remains under the considerable scope to increase the treatment ability of hazardous leachate. This proposed treatment will conserve surface water and ground water and save energy as well. Leachate used in this study was provided from a drainage system of a landfill in Borg El-Arab city, Egypt. The leachate produced from the studied landfill has a high concentration of ammonia that ranged from 115 mM to 160 mM. Batch laboratory experiments were performed using synthetic wastewater composed of ammonia and nitrite in the theoretical stoichiometric molar relationship ratio (1:1.32) to enrich anammox granules. This experiment was followed by using real sanitary landfill leachate produced from partial nitritation process (PN). Partial nitritation reactor was operated at constant hydraulic retention time (24 h), using three different leachate concentrations, namely, 5.9%, 25%, and 50%. The results showed that the partial nitritation process ranged from 30% to 50.8% over the study period due to the inhibition of nitrite-oxidizing bacteria by free ammonia and free nitrous acid. Ammonia reduction up to 85% has been achieved in the anammox reactor. Corresponding nitrite reduction was almost 99% in the anammox reactor. This study revealed that Broccadia species in the anammox reactor was demonstrated to be responsible for the anammox process.

Modeling of an integrated air gap membrane distillation unit utilizing a flat plate solar collector

This work investigates the incorporation of a flat plate solar collector into an air gap membrane distillation (AGMD) system to produce pure water from water wells in Egypt. First, it considers the metrological data for Borg El Arab city, which is located at the north of the western desert in Egypt. A three-dimensional AGMD numerical model is established and solved using ANSYS 2019 commercial software, after setting suitable boundary conditions. Once the pure water flux is predicted at certain feed water inlet and outlet temperatures, a thermal analysis of the flat plate solar collector is introduced to estimate the required solar collector area to produce the required pure water flux.

Land cover/use change analysis and mapping of Borg El-Arab City, Egypt

One of the essential steps for agricultural development planning is the recognition of land cover and land use LCLU classes and the associated changes with time, in which LCLU avails as one of the major input criteria. The North coastal region of Egypt is exposed to significant spatial and temporal changes in LCLU classes (urban, agriculture, and water bodies) that basically affect any kind of development programs. Borg El-Arab City represents a potential community and new industrial site for future development in the region. The supervised classification of Landsat satellite images and computation of the normalized difference vegetation index (NDVI) are applied as effective tools in the study area to observe the LCLU changes. Landsat 5, 7, and 8 satellite images were used and four images dated in 1986, 1999, 2006, and 2017 were selected. The area under consideration was classified into seven main classes ,e.g., Mediterranean Sea, salt marshes, agriculture, urban, bare land, swamps and wet land, and shoreline strip. The area was subjected to significant changes in the last three decades as a result of the reclamation projects growing and industrial effectiveness as well. Taking the whole period (1986–2017) into consideration, results show that the study area is exposed to a wide range of gain or loss in the area of different land cover classes, particularly in regard to the agriculture area, urban land, and bare land. The surface area of urban land, agriculture land, and water bodies increased on the expense of decreasing the bare land, where it lost 31.3%. The urban area expanded into much of the agricultural and the agricultural land expanded into bare land. In light of the recognized change causes, approach policy suggestions for better management of LCLU can be established.

Quantitative and Qualitative Genetic Studies of Some Acacia Species Grown in Egypt.

The objective of the current work is to study the genetic differentiation between Acacia species growing in Egypt as plant genetic resources based on morphological, biochemical, and molecular markers. The 20 replicates of Acacia tree collected from four localities from Egypt were A. tortilis ssp. raddiana and A. farnesiana (Siwa Oasis and Borg El-Arab City), A. stenophylla, A. sclerosperma (Marsa Matroh City), and A. saligna (Abis Station Farm, Alexandria). The results based on the previous markers indicated highly significant differences between Acacia species, confirming the hypothesis of the possibility of using morphological, biochemical, and molecular parameters in species identification. Qualitative characteristics results indicated some similarities and differences that are taxonomically important for comparing taxonomical grouping with morphological data for the genetic description of Acacia species. The activities of antioxidant enzymes have been studied intensively and the results provide strong similarities between the Acacia species (69%), between A. raddiana (Siwa and Borg Al-Arab) and A. saligna, followed by all Acacia species (50%). Finally, the molecular studies showed that a total of 563 amplification fragments, 190 fragments were monomorphic, and 373 fragments were polymorphic. The highest number of amplification fragments (21) was detected with OPB-20 primer, while OPA-20 showed seven amplification fragments; the average number was 13.09. The results indicated that Acacia species exhibit high genetic differentiation, helpful in the future for genetic improvement programs. The novelty of the current study is highlighting the importance of plant genetic resources in Egypt and using different techniques to measure the differentiation between these species.

Assessment of different passive solar stills via exergoeconomic, exergoenvironmental, and exergoenviroeconomic approaches: A comparative study

In this study, comparative performance assessment of different passive solar stills systems based on energy matrices, exergy, economic, exergoeconomic, environmental, exergoenvironmental, enviroeconomic, and exergoenviroeconomic viewpoints is performed. Six systems of passive solar stills are considered namely, traditional solar still (TRD still), solar still with phase change materials (PCM), solar still with PCM embedded in a pin fin heat sink (PCM-PF), solar still with PCM incorporated with steel wool fibers in the basin (PCM-SWF), solar still with SWF only in the basin (with SWF) and finally solar still with pin fined heat sink in the basin (with PF). The performance of the six systems is experimentally evaluated and compared to each other under the same meteorological conditions of New Borg El-Arab City, Egypt (Longitude/Latitude: E 029°42′/N 30°55′). The results indicated that PCM-based solar stills systems performed poor performance based on energy matrices, freshwater production cost, exergoeconomic, exergoenvironmental and exergoenviroeconomic parameters. Whereas, solar still with SWF gives the highest performance among all studied systems by employing these enhanced (exergy/economic/environmental) approaches. The daily energy and exergy outputs for conventional still are the minimum at 2.5 and 0.1528 kWh/day, respectively and still with SWF are the maximum at 2.856 and 0.1869 kWh/day, respectively. The annual amount of CO2 emission mitigated for conventional still, still with PCM, still with PCM-PF, still with PCM-SWF, still with SWF and still with PF are 33.02, 35.88, 38.26, 37.05, 41.6 and 38.35 tons, respectively based on energy approach. Whereas, the corresponding values based on exergy are 0.961, 0.6652, 0.6217, 0.756, 1.56 and 1.189 tons, respectively.

An experimental work on the performance of single slope solar still incorporated with latent heat storage system in hot climate conditions

The limit production of freshwater is considered the main problem of solar still. So, the objective of this work is studying the performance of single slope solar still coupled with phase change materials as a thermal storage unit and its effect on the still productivity. In view of this, different cases are considered namely, Case 1: solar still without phase change material (conventional solar still), Case 2: solar still coupled only with phase change material attached to the still base, Case 3: solar still with hollow cylindrical pin fins imbedded in the phase change material, case 4: solar still with phase change material and steel wool fibers in the still basin and case 5: solar still with only steel wool fibers in the still basin. The performance of the solar still for the five cases is experimentally evaluated and compared to each other's under the same climate conditions of New Borg El-Arab City, Egypt (Longitude/Latitude: E 029°42′/N 30°55′). The results revealed that the presence of phase change material negatively affects the daytime freshwater productivity with a significant increment in the overall freshwater yield of the still. Also, solar still with phase change material-based pin finned (Case 3) achieves the best thermal performance compared to conventional still (Case 1) and solar still with phase change material (Case 2). It is perceived that the total daily cumulative yield of distillated water of Case 3 is higher than those of case 1 and case 2 by 17 and 7%, respectively. Additionally, placing steel wool fibers in the basin accompanied with phase change material significantly enhances the daytime freshwater productivity with a considerable reduction in overnight productivity and an increase of the overall day productivity. Moreover, using steel wool fibers in the basin with a phase change material based solar still (case 4) enhances the total daytime freshwater productivity by 14% with a drop in the overnight productivity by 80%, compared to case 2. Among all tested configurations, case 5 achieves the highest accumulated daily freshwater productivity (approximately 25% an enhancement in the daily productivity compared to case 1) and thermal efficiency with minimum cost.

Energetic and exergetic performance assessment of the inclusion of phase change materials (PCM) in a solar distillation system

In this experimental work, the energetic and exergetic performance enhancement of solar distillation system (solar still incorporated with PCM storage unit) is performed by using two techniques. First, pin fins heat sink (PF) is embedded inside the PCM to act as a thermal conductivity enhancer. Second, black steel mesh fibers (SWF) are employed in the solar still basin with PCM. In this regard, four cases of the solar stills are studied and compared conventional still: conventional solar still (without PCM), still with PCM (With PCM), still with PCM and pin fins heat sink embedded in the PCM (With PCM-PF) and still with PCM and SWF in the basin (With PCM-SWF). The energetic and exergetic performance of the four cases is evaluated and compared under the meteorological conditions of New Borg El-Arab City, Egypt. The results show that the total daily cumulative yield of distilled water of still with PCM, still with PCM-PF, and still with PCM-SWF are greater than of conventional still by 9.5%, 16.8%, and 13%, respectively. Additionally, the inclusion of the fins heat sink in the PCM increases the average daily energy and exergy efficiencies by 17.9, and 13.2%, respectively compared to conventional one. Likewise, the energy and exergy efficiencies of still with PCM-PF are higher than those of solar still with PCM by 7.7 and, 6.8%, respectively. Furthermore, placing SWF in the basin of still with PCM significantly enhances the daytime energy and exergy efficiencies with a considerable reduction of these values in the nighttime. The total daily evaporative exergy for still with PCM-SWF is greater than those of conventional still, still with PCM, and still with PCM-PF by 13, 8, and 2%, respectively. Also, still with PCM, still with PCM-PF, and still with PCM-SWF exhibit an increment of the daily exergy efficiency 5.9, 13.2, and 17.3%, respectively compared to still without PCM. Still with PCM-PF achieved the highest accumulated daily water productivity and energy efficiency but still with PCM-SWF attained the highest daily exergy efficiency with nearly no additional cost.