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This work provides technical and economic feasibility of installing a solar chimney power-water distillation plant (SCPWDP) in the port of Aqaba in Jordan. A mathematical model for the SCPWDP has been developed and validated. A full year of weather conditions data has been processed, where water and electricity productions have been estimated. The results show that the SCPWDP can produce 481,440 kWh of electricity and 123,753 ton of distilled water yearly simultaneously. The economic analysis shows that the levelized cost of energy (LCOE) for the SCPWDP is $1.86/kWh. The cost estimate seems reasonable once compared with other studies. However, from economical point of view the LCOE of SCPWDP requires a further decrease in order to make it economically feasible. The sensitivity analysis shows that increasing the chimney height of the SCPWDP would increase the production of electricity, and hence, decreases the LCOE. However, increasing the chimney height would have a marginal improvement since it increases both capital and operation expenditures.

This study presents a novel design that combines cooling tower (CT) and traditional solar chimney power plant (SCPP) technologies for electricity generation and seawater desalination. The proposed hybrid solar chimney power plant (HSCPP) shares the operation of the chimney part and the bi-directional turbine between the SCPP and CT, allowing alternative operation of the CT during the nighttime and the SCPP during the daytime, and achieving continuous system utilization. The performance of the HSCPP design was validated against baseline models using 1 year of weather data from the city of Aqaba in Jordan. Results revealed that the HSCPP has the potential to produce 50% electricity (528 MWh/year) higher than the traditional SCPP (365 MWh/year). The annual seawater desalination capacity of the HSCPP was estimated at 138300 m 3 , which is 1.5 folds higher than the traditional SCPP. The HSCPP reduced the annual CO 2 emissions by 40% (500 tons) compared to traditional SCPP with annual revenue of US$190 000. Furthermore, the results show that the HSCPP is 1.4 times more efficient than the traditional SCPP. The HSCPP achieved a system utilization factor of 0.73% compared to 0.52% for the traditional SCPP. The HSCPP showed promising sustainable and economical technology for the production of electricity and water while reducing the emission of GHG.

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The adhesion enhancement of graphene oxide (GO) and reduced graphene oxide (rGO) layer in the underlying polyethersulfone (PES) microfiltration membrane is a crucial step towards developing a high-performance membrane for water purification applications. In the present study, we modified the surface of a PES microfiltration membrane with plasma treatment (PT) carried out at different times (2, 10, and 20 min). We studied the effect of PT on the adhesion, stability, and performance of the synthesized GO/rGO-PES membranes. The membranes’ surface morphology and chemistry were characterized using atomic force microscopy, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The membrane performance was evaluated by conducting a diffusion test for potassium chloride (KCl) ions through the synthesized membranes. The results revealed that the 2 min PT enhanced the adhesion and stability of the deposited GO/rGO layer when compared to the other plasma-treated membranes. This was associated with an increase in the KCl ion rejection from ~27% to 57%. Surface morphology analysis at a high magnification was performed for the synthesized membranes before and after the diffusion test. Although the membrane’s rejection was improved, the analysis revealed that the GO layers suffered from micro/nano cracks, which negatively affected the membrane’s overall performance. The use of the rGO layer, however, helped in minimizing the GO cracks and enhanced the KCl ion rejection to approximately 94%. Upon increasing the number of rGO deposition cycles from three to five, the performance of the developed rGO-PES membrane was further improved, as confirmed by the increase in its ion rejection to ~99%.

This study presents a case study of a novel hybrid solar chimney power plant (HSCPP) design’s performance in the city of Doha, Qatar. The HSCPP construction is similar to the traditional solar chimney power plant (SCPP) but with the addition of water sprinklers installed at the top of the chimney. This allowed the solar chimney (SC) to operate as a cooling tower (CT) during the nighttime and operate as an SC during the daytime, hence providing a continuous 24-h operation. The results showed that the HSCPP produced ~633 MWh of electrical energy per year, compared to ~380 MWh of energy produced by the traditional SCPP. The results also showed that the HSCPP was able to produce 139,000 tons/year of freshwater, compared to 90,000 tons/year produced by the traditional SCPP. The estimated CO2 emission reduction (~600 tons/year) from the HSCPP is twice that of the traditional SCPP (~300 tons/year). The results clearly show that the HSCPP outperformed the traditional SCPP.

Abstract:In this work, we report the transfer of graphene onto eight commercial microfiltration substrates having different pore sizes and surface characteristics. Monolayer graphene grown on copper by the chemical vapor deposition (CVD) process was transferred by the pressing method over the target substrates, followed by wet etching of copper to obtain monolayer graphene/polymer membranes. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle (CA) measurements were carried out to explore the graphene layer transferability. Three factors, namely, the substrate roughness, its pore size, and its surface wetting (degree of hydrophobicity) are found to affect the conformality and coverage of the transferred graphene monolayer on the substrate surface. A good quality graphene transfer is achieved on the substrate with the following characteristics; being hydrophobic (CA > 90 • ), having small pore size, and low surface roughness, with a CA to RMS (root mean square) ratio higher than 2.7 • /nm.