R.E.D.S

A novel design of reverse osmosis (RO) membrane is performed for wastewater treatment processes in Al-Marj, Libya. In Al-Marj area, industrial wastewater formed sewage ponds in the region, which posed a great danger to the surrounding environment. Sewage ponds have been formed because of the existence of natural gas and oil refinery stations in that area. The proposed system will recycle the sewage pond wastewater in order to provide approximately 3,500–10,500 m3/d of freshwater. The produced fresh water is expected to serve around 55,000 inhabitants in a semi-arid area. Reverse osmosis membrane processes will be used for freshwater production. Concentrated Solar Gas Engine will be used as a main source of power for reverse osmosis operation. Solar Stirling dish engine with CO2  working gas is considered a new vital option in such an application. The hydraulic power system (lower tank, pump, upper tank, and hydraulic turbine) is used as an energy recovery storage system instead of using batteries or diesel generators. The results reveal that the total water price was in the range of 0.65 $/m3, and the specific power consumption was not exceeding over 4 kWh/m3.

Nowadays, designing new poly-generation systems is needed to meet the increasing communities demands of electrical energy, space cooling and fresh water. This should take more attention especially with the increasing conventional fossil fuel energy costs, freshwater shortage and CO2 emission. This work presents the thermodynamic analysis of a sustainable poly-generation thermal system that can produce electricity, space cooling and desalinated water. The proposed system combines a Concentrated Solar Power (CSP), Steam Rankine Cycle (SRC), Multi Effect Distillation (MED) system and Absorption Refrigeration System (ARS). The system design target is to provide communities in remote areas with all needs of water, electricity and cooling using low-grade heat from green solar energy. In the solar field, solar irradiation is collected by Parabolic Trough Collectors (PTC) to heat the working fluid (Therminol-VP1 heat transfer oil). Thermal oil transfers the absorbed heat to the SRC that generates the required electrical power and provides both MED and ARS with a proper heating steam required depending on the demand loads. The developed model is used to design a pilot test unit of 10 kW electrical power, 1.7 m3/day of desalinated water and 3.6 TR cooling load capacity. flow, heat, and exergy destruction rates for each component of the system are obtained. Performance parameters of the subsystems forming the plant are also evaluated. Results revealed that the PTC represent the most critical part in the system from the exergetic point of view as it experiences 84.65% of the total system exergy destruction the required PTC area is 83.12 m2. For the ARS unit, exergy loss is about 2.2 kW, 36.22% and 28.87% of this value occur in absorber and generator respectively. MED unit simulation results demonstrated that the gain ratio and specific heat transfer area are 2.29 and 144 m2/kg/s respectively. The exergy destruction in the MED unit is 1.8244 kW (66.43% in evaporators and 33.57%in condenser). The ARS coefficient of performance and second law efficiency were 0.7755 and 59.24% respectively.

Solar-Wind systems are growing as a vital option to power different types of membrane desalination processes. It is becoming very important to use renewable power sources because of zero emissions to the environment. In this work, solar photovoltaic (PV) system is used to power on the reverse osmosis (RO) desalination process. Meanwhile, Vertical Wind Turbine (VWT) system has been used as a recovery system during sun absence periods. Moreover, the possibilities to operate a hybrid system of PV-VWT  combined with RO system has also investigated. The system is designed to desalinate a low rate of fresh water at a scale capacity of 0.1-1m3/day. The system is contained as a mobile unit which can be used to serve rural areas during safari and tourism travels in deserts with some features such as, compactness, stability, and ease of maintenance. The unit product cost (UPC, $/m3) is found in the range of 1.51$/m3. 

Conference paper

Flat plate collectors are sophisticated greenhouses that trap and use the heat from sun to rise the temperature of water up to about 70 oC. Useful energy from the sun is transferred to the tubes that are mounted with the absorber plate. Solar collectors are widely used to provide hot water in hospitals, hotels, buildings, industrial applications and for thermal energy systems. The solar liquid heaters especially flat plate solar collector generally consists of a sheet of thermally conductive material called absorber plate to which are bonded the tubes carrying the heat transfer liquid, usually water. Solar radiation is transmitted through the transparent cover and is converted to heat on the absorber plate. A Neural model that represents the experimental performance results is developed. The proposed neural model can be used to determine the proper performance of the flate plate collector. Artificial neural networks are used to achieve the paper aims due to their advantages such as its ability to deduce relations between data, readings, or complicated information, also its capability for adaptive learning, self–organization, and resisting fault. In another say, the (ANN) are distinguished by its fast computation, easy interpolation, and implementation capability. In the results part, there are comparisons between the experimental readings with ANN simulation readings in order to give a point of view about the fidelity of our model.

A master thesis about solar still combined with solar collectors. In the present work, a small size of a solar still distillation unit coupled with different types of low concentration ratios of solar water heater (i.e. Flat plate solar water heater and evacuated tube solar water heater) has been designed and tested in many ways, especially for producing a small amount of potable water for small groups of people (army units, nomads,... etc.). Systems were designed and investigated at the Faculty of Petroleum and Mining Engineering at Suez-Egypt. It was operated and investigated under real environmental conditions. Theoretical study for the all experimental work was performed. 

Master thesis based on tubular solar still design and performance.

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"STUDY OF WATER DESALINATION BY SOLAR ENERGY USING MULTI-STAGE FLASH (MSF) PROCESS" is a master thesis about a small unit of MSF desalination process. Flat plate solar collector is used to power on (thermally) the MSF. It is useful for small communities and small groups of people.

Wind energy plays a vital role in the quest for renewable and sustainable energy as well as in reducing carbon emission.
There are a lot of numerical techniques that are performed in order to design and simulate the wind turbines. However;
such numerical techniques are focused on structure, blade design, blade fatigue, aerodynamics analyses, etc. In this work,
new correlations are implemented for the design and simulation of different types of wind turbines (Horizontal and Vertical). The numerical correlations are performed by the use of Mat Lab/SimuLink tool box. Moreover; Artificial Neural Network (ANN) numerical technique is used to simulate and evaluate the designed modules. The implemented correlations may help the designer and\or investor in order to elect a specified wind turbine according to the demanded load and design the wind farm. The results reveal that the implemented correlations show a very good matching with the actual commercial data points of the wind turbines. 
 

Thermo-economy is a useful and powerful tool that combines thermodynamics and economics. It can evaluate how irreversibility and costs of any process affect the exergoeconomic cost of the product. In this work, a number of comparisons for solar thermal-powered different recovery units for reverse osmosis desalination system are performed using thermo-economic analysis. Three different configurations are used for this comparison (Basic, Pelton Wheel Turbine, and the Pressure Exchanger) with Sharm El-Shiekh RO desalination plant for a total productivity about 145.8 m3/h (40.5 kg/s). As a result of this analysis, the unit product cost of Pelton Wheel Turbine (PWT) and Pressure Exchanger (PEX) configurations are 24% and 24.2% respectively less than that of the basic configuration. Thermo-economic analysis shows that the minimum investment and operating & maintenance costs are obtained by PEX configuration. Also, it achieves minimum exergy destruction against the two other configurations (Pelton Wheel and Basic systems). Therefore, the final conclusion of this work is that the PEX configuration is more economical than either stand alone or PWT configurations. 

Comparisons between different desalination processes regarding to solar systems are performed. 

Solar power assisted different techniques of MED-VC (multi effect distillation-vapor compression) processes is thermo-economically analyzed and evaluated. In this work, two techniques of solar power cycles are considered to power on MED-PF-TVC, MVC (multi effect distillation thermal and mechanical vapor compressions). In the first technique, the developed solar thermal power is directly transmitted from the solar collector field via boiler heat exchanger unit toward the steam ejector of the MED-PF-TVC process. In the second technique, the electrical power generated from the SORC (Solar Organic Rankine Cycle) is used to power on the vapor compressor of the MED-PF-MVC process. The comparison is implemented according to the operation of PTC (parabolic trough collector) with Toluene organic oil and Water working fluids (2nd technique). Therminol-VP1 HTO (Heat Transfer Oil) is considered across the solar field and water is considered for boiler heat exchanger (1st technique). A case study is performed according to 4545 m3/day of distillate product. As a result, reducing the value of compression ratio with increasing the evaporator’s numbers would reduce the specific power consumption, solar field area, and thermo-economic costs. Also it is clear that the operation of steam ejector would increase the gain ratio instead of increasing the evaporator’s numbers. 

Discover a new small unit for solar MSF desalination process.

The operation of large-scale reverse osmosis units in combination with different solar power plants, both, Concentrating Solar Power (CSP) and Photovoltaics (PV) has been evaluated under variable load conditions. In the case of the Reverse Osmosis (RO) unit, configurations with and without an energy recovery device have been considered. In the case of the CSP plant, a thermal storage system with several capacities (8–14 h) covers the periods with low solar radiation and no storage has been taken into account for the PV plant due to the prohibitively high cost of batteries at large scale. Two scenarios and different strategies within each scenario have been proposed to adapt the operation of the RO unit at partial load in order to assure a stable operation. In the first scenario, the RO unit is represented as a whole unit with variable performance according to the power availability. In the second scenario, the RO unit is composed of 10 sub-units that are switched on/off depending on the power availability. The analysis has been done for a specific location in Algeria and the dynamic performance of the RO unit has been presented for each scenario, together with an economic analysis. 

Discover how to use solar energy for margarine melting heat process.

It is important for many solar energy systems to estimate and predict the instant or daily mean direct and diffuse irradiation on horizontal or tilted surfaces at any known location. One of the targets of the present article is to perform a simple statistical evaluation of 7 model results. These models are employed to estimate and predict the solar radiation on different surfaces and locations. They are fed with local measured data. The results of the evaluation would help to recommend one or more models for the considered region (latitude: 29o N; longitude: 33o  E). Statistical indicators, such as Mean Bias Error (MBE), Root Mean Square Error (RMSE) and Mean Relative Percentage Error (MPE) are used in this comparison. The considered models are ASHREA, ATWATER&BALL, BIRD, DAVIES&HAY, HOYT, LACIS&HANSEN and SPECTRAL2. The obtained results have shown that, BIRD and DAVIES&HAY models could be recommended for estimating both the instantaneous hourly direct and diffuse radiation on horizontal surfaces for the considered region. And, ASHREA, SPECTRAL2 and ATWATER&BALL are occupied the second rank. Models such as HOYT and LACIS&HANSEN would not recommend for the considered region. Also, a new correlation is developed by which the total insolation could be predicted.  

This article proposes new methods of modeling and simulation of photovoltaic and horizontal wind turbine systems. The photovoltaic and horizontal wind turbines are modeled by the use of actual data sheets listed in the lookup table model. Moreover, artificial neural network numerical technique is used to simulate and evaluate the designed systems. The implemented work may help the designer and investor to elect a specified photovoltaic module and/or the horizontal wind turbine according to the demanded power load, hence predicting the operating conditions before the establishment process. The results show good matching with the actual data for the photovoltaic and horizontal wind turbine systems. 

Process simulation has become an accepted tool for the performance, design, and optimization calculations of solar desalination process units. Solving the mathematical models representing these units and systems is a tedious and repetitive problem. Nested iterative procedures are usually needed to solve these models. Also, the process configurations are characterized by existence of a number of recycle streams. To tackle these problems, several researchers have developed different methods, techniques, and computer programs for the simulation of a very wide range of variety of solar desalination process units and systems. It is of interest in this work to show and demonstrate a new program working under Matlab/SimuLink environments for solar desalination processes calculation and modeling. Using these environments a visual design and simulation for different types and configurations of standalone (common) and solar desalination processes can be performed. Embedded user block programming with SimuLink is implemented to construct a flexible reliable and friendly user-interface package. The solar heating systems and desalination plant components (named here as blocks), such as heat exchangers, flash chambers, evaporators, pumps, steam ejector, compressor, reverse osmosis membrane, pipes, etc., are stored as icons in a visual library. This library enables the user to construct different configurations by just clicking the mouse over the required units (blocks). The interface aids designers, and operators to perform different analyses and calculations such as energy, exergy, and thermoeconomics. Typical desalination processes such as multi stage flash, and reverse osmosis are presented to show the wide scope and the validity,
reliability, and capability of the developed package.

The recourse to renewable energy systems in general has become a reality. Thus, it has become very important for engineers to design and simulate such systems that serve the renewable desalination plants. A computer software package has been developed by the authors for design and simulation of renewable energy desalination systems (REDS). This was motivated by unavailability of such packages in the literature or on a commercial scale. Solar desalination systems, wind desalination systems, and geothermal desalination systems software libraries became affirmative parts of the main REDS software library. This library enables the user to construct different configurations by clicking the mouse over the required units (blocks). The interface aids designers, scientists, and operators to perform different analyses and calculations such as energy, exergy, cost, and thermoeconomics. Typical desalination processe such as a multi-stage flash, multi-effect distillation, and reverse osmosis are numerically modeled and embedded within the main library of the developed software. REDS shows a wide scope of validity, reliability, and capability to model and simulate renewable desalination systems.

Thermal desalination plants need large amounts of fuel to desalinate large quantities of seawater. At the same time, burning non-beneficial gases in the oil refineries is considered a huge waste of energy instead of using it. In this paper, a novel study on the possibility of operating the thermal desalination plants by waste gases that emerged from oil refineries rather than burning these gases in the air is performed. Hybrid MSF-MED thermal desalination processes are utilized in this study to produce a total range of 100–40,000 m3/day. Three scenarios are performed utilizing the waste gases with MSF-MED. The comparison brings out that using waste gases would save roughly 1136 $/h (UHC-unit hourly costs, $/h) while comparing against the conventional natural gas operation. Moreover; 5 m3/h of waste gases would produce an amount of 58–60 MW of electric power combined with a production of 100 m3/d of fresh water (gas turbine cycle scenario) and 4.5–5 MW combined with a production of 40,000 m3/d in case of organic Rankine cycle operation. Based on energy and exergy balances, the 3rd scenario gives remarkable results.

Organic Rankine cycles (ORC) have unique properties that are well suited to solar power generation. In this work design and performance calculations are performed using MatLab/SimuLink computational environment. The cycle consists of thermal solar collectors (Flat Plate Solar Collector (FPC), or Parabolic Trough Collector (PTC), or Compound Parabolic Concentrator (CPC)) for heat input, expansion turbine for work output, condenser unit for heat rejection, pump unit, and Reverse Osmosis (RO) unit. Reverse osmosis unit specifications used in this work is based on Sharm El-Shiekh RO desalination plant. Different working fluids such as: butane, isobutane, propane, R134a, R152a, R245ca, and R245fa are
examined for FPC. R113, R123, hexane, and pentane are investigated for CPC. Dodecane, nonane, octane, and toluene are allocated for PTC. The proposed process units are modeled and show a good validity with literatures. Exergy and cost analysis are performed for saturation and superheated operating conditions. Exergy efficiency, total exergy destruction, thermal efficiency, and specific capital cost are evaluated for direct vapor generation (DVG) process. Toluene and Water achieved minimum results for total solar collector area, specific total cost and the rate of exergy destruction. 

The presence of surfactant additives in water is found to enhance the boiling heat transfer significantly. The effect of using a surfactant as sodium lauryl sulfate (SLS) in relatively small dosages of concentration with a small size unit of solar water distillation process is investigated. Sun simulator (electric heater and variac transformer) is used to quantify the same input power for each experiment for the system instead of the sun. The experimental results show that a small amount of surfactant additive makes the top brine temperature (TBT) considerably higher, hence the freshwater product. Temperature curves for various surfactant concentrations are obtained and compared. The percentage of the increase in the system productivity is 0.7%, 2.5%, 4.7% and 7% at additive concentration equal to 50, 100, 200 and 300 ppm respectively. It is found that increasing the surfactant concentration more than 300 ppm not affecting the system daily productivity (DP) and TBT. Using surfactant concentration more than 400 ppm will decrease the DP by 6%. 

Solar energy with different configurations of multi-effect distillation process is thermo-economically evaluated. In this work, two different combined solar cycles with different configurations of multi effect distillation (MED) processes are considered. In the first technique, the solar energy is directly utilized from the solar collector field via evaporator heat exchanger to the first effect of the MED process. This technique produces only potable water. In the second technique, the exhausted energy from the organic Rankine cycle (ORC) turbine is used in the first effect of the MED process. The second technique produces power electricity and desalted water. The comparison is implemented according to the operation of Parabolic Trough Collector (PTC) with toluene organic oil and water working fluids. Therminol-VP1 Heat Transfer Oil (HTO) is considered for indirect vapor generation operation across the solar field and evaporator heat exchanger. The comparisons are manipulated according to 100 m3/day of distillate product as a case study. As a result, only desalination technique is considered more attractive than desalination and power technique due to higher gain ratio and lower solar field area needed. Parallel feed configuration is dominated against the forward feed with feed heater configuration while increasing the number of effects to more than 12 effects. 

Solar thermal power cycles assisted multi-stage flash brine recycle (MSF-BR) distillation process are thermo-economically analyzed and evaluated. In this work, the analyses are compared according to three different configurations via two techniques of solar thermal power cycles. The first technique is considered for only desalination process; however, the second is considered for desalination and electric power generation via organic Rankine cycle. Solar parabolic trough concentrator (PTC) field is considered to dominate sufficient thermal power for MSF plant. Water steam working fluid is used for a direct vapor generation (DVG); however, Therminol-VP1 working substance is used for an indirect vapor generation (IDVG) through the PTC field. Moreover, the optimized configuration from the first technique is compared with the power generation and desalination (the second technique). The comparisons are proceeding for the MSF-BR desalination plant with total productivity in the range of 5,000m3/d which the gain ratio is increased up to 12 with 40 stages. The thermo-economic results reveal that first technique achieves remarkable results related to the PTC area, the SPC, kWh/m3, and the thermo-economic product cost, $/GJ. 

This article presents a novel work related to synthesis and utilize ZnO nanoparticles to enhance solar still distillation productivity. The hydrothermal synthesis method based on using different solvents such as methanol and ethylene glycol was used in the synthesis of ZnO nanoparticles. The resulting oxide nano-materials nano-rod (100 nm length, 10–15 nm diameter) and nano-sphere (250 nm diameter) were characterized using field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), UV–vis absorption spectroscopy, and X-ray diffraction. The analyses show  that the solvent controlled the size and morphology of the produced nano-particles. The synthesized ZnO nonmaterial is used as an important application for solar still. The effect of ZnO nonmaterial shape and its concentration on the performance of the solar still were investigated. The results showed a great effect of
the nanomaterials on the performance of the solar still. Results reveal that nano-rod shape achieves range of 30% and 38% of increase in solar still productivity and efficiency respectively compared against the nano-sphere shape.

This article presents a performance study of using different working fluids (gases) to power on Concentrated Solar Gas Engine (CSGE-Stirling and/or Brayton). Different working gases such as Monatomic (five types), Diatomic (three types) and Polyatomic (four types) are used in this investigation. The survey purported to increase the solar gas engine efficiency hence; decreasing the price of the output power. The effect of using different working gases is noticed on the engine volume, dish area, total plant area, efficiency, compression and pressure ratios thence; the Total Plant Cost (TPC, $).

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Design and simulation of solar desalination systems is a PhD thesis about how to make the model of solar desalination systems via matlab/simulink.

PhD Thesis presentation

Learn the Idea behind the model construction of the REDS library through the PhD presentation.

Photovoltaic (PV) solar energy has become very important in power systems. PV systems became an affirmative part in power grids. For engineers; it is very important to design and simulate such systems that serve the solar plants. The PV modules are modeled by the use of actual manufacturers' data listed in the lookup table model. The lookup table is performed by the use of MATLAB/Simulink toolbox based. Moreover; Artificial Neural Network (ANN) numerical technique is used to simulate and evaluate the designed modules. The implemented work may help the designer and/or investor in order to elect a specified PV module according to the demanded power load thence; designing the PV fields for many of power applications. The results show a very good matching with the actual commercial data points of the PV systems.