Hilal Al-Hinai

Fouling of Reverse Osmosis and Ultrafiltration Membranes: A Critical Review

Abstract Desalination by using reverse osmosis (RO) membranes has become very popular for producing freshwater from brackish water and seawater. Membrane lifetime and permeate flux, however, are primarily affected by the phenomena of concentration polarization and fouling at the membrane surface. The scope of the current paper was to critically review the literature on the fouling phenomena in RO and ultrafiltration (UF) membrane systems, the analytical techniques used to quantify fouling, preventive methods, and membrane cleaning strategies. The paper also makes specific recommendations on how scientists, engineers, and technical staff can assist in improving the performance of these systems through fundamental and applied research.

An ANN-based approach for predicting global radiation in locations with no direct measurement instrumentation

In this work, a novel approach using an artificial neural network was used to develop a model for analyzing the relationship between the Global Radiation (GR) and climatological variables, and to predict GR for locations not covered by the models training data. The predicted global radiation values for the different locations (for different months) were then compared with the actual values. Results indicate that the model predicted the Global Radiation values with a good accuracy of approximately 93% and a mean absolute percentage error of 7.30. In addition, the model was also tested to predict GR values for the Seeb location over a 12 month period. The monthly predicted values of the ANN model compared to the actual GR values for Seeb produced an accuracy of 95% and a mean absolute percentage error of 5.43. Data for these locations were not included as part of ANN training data. Hence, these results demonstrate the generalization capability of this novel approach over unseen data and its ability to produce accurate estimates. Finally, this ANN-based model was also used to predict the global radiation values for Majees, a new location in north Oman.

Thermodynamic and economic considerations in solar desalination

Abstract The thermodynamic efficiency of single-basin and multiple-effect solar water desalination systems was critically reviewed with special emphasis on humidification-dehumidification processes. Solar energy may be used, either directly or indirectly, to produce fresh water. The concept of using the humidification-dehumidification process in combination with the growth of crops in a greenhouse system, however, is relatively new. System economics was also covered since it affects the final cost of produced water. While a system may be technically very efficient, it may not be economic. The challenges and opportunities of solar energy were also briefly discussed. The paper closes with a summary of key factors affecting system performance and recommendations for future areas of investigation and development.

Modeling and performance analysis of a solar desalination unit with double-glass cover cooling☆

Abstract In this study, modeling and performance analysis of a single-basin solar still with the entering brine flowing between a double glass glazing is investigated. The base area of the solar still is 1 m2. The function of this arrangement is two-fold; lowering the glass temperature and preheating the entering brine. This resulted in improved performance represented by a faster rate of evaporation from the basin. The efficiency of the double-glass desalination unit increased by over 25% compared with the conventional single-basin single-glass solar still. The hourly and daily productions of the unit and the temperatures of the water and the glass cover were also predicted under the meteorological conditions of Muscat, Oman.

Parametric investigation of a double-effect solar still in comparison with a single-effect solar still

Abstract This paper reports the use of two mathematical models to compare the productivity of single-effect and double-effect solar stills under different climatic, design and operational parameters in Oman. The shallow water basin, 23° cover tilt angle, 0.1 m insulation thickness, and asphalt coating of the solar still were found to be the optimum design parameters that produced an average annual solar still yield of 4.15 kg/m 2 /d and 6 kg/m 2 /d for single and double effect solar stills, respectively. A cost analysis is carried out to shed some light on the potential of utilizing an array of single-effect solar stills or double-effect solar stills for the production of drinking water in remote areas in Oman. It has been found that the unit cost for distilled water using an array of single-effect solar stills is

Simulation of fresh water production using a humidification-dehumidification seawater greenhouse

74/1000 gal (16.3

VARI-RO solar-powered desalting technology

/m 3 ) or

Capacity-building strategies for desalination: activities, facilities and educational programs in Oman

62.4/1000 gal (13.7

SIMULATION OF THE CONDENSER OF THE SEAWATER GREENHOUSE Part I: Theoretical development

/m 3 ) when using a double-effect solar still. The cost saving is 15.7%.

Total fog and rainwater collection in the Dhofar region of the Sultanate of Oman during the monsoon season

A thermodynamic simulation study was performed on the influence of greenhouse-related parameters on a desalination process that combines fresh water production using humidification-dehumidification with the growth of crops in a greenhouse. With the system under study, surface seawater trickles down a porous front wall evaporator through which air is drawn into the greenhouse. The saturated air passes through a condenser, which is cooled using cold deep seawater or cool seawater coming out of the evaporators. Thermodynamic modeling of the seawater greenhouse system in our laboratory has shown that the dimension of the greenhouse had the greatest overall effect on water production and energy consumption. A wide shallow greenhouse, 200 m wide by 50 m deep gave 125 m3.d−1 of fresh water. This was greater than a factor oftwo compared to the worst-case scenario with the same area (50 m wide by 200 m deep), which gave 58 m3.d−1. Low power consumption went hand-in-hand with high efficiency. The wide shallow greenhouse consumed 1.16 kWh.m−3, while the narrow deep structure consumed 5.02 kWh.m−3 . The benefits of the development of the seawater greenhouse for arid regions are discussed.