MODELING AND DESIGN OF OSMOTIC POWER PLANT: AN INVESTIGATION ON OPERATING FACTORS

Worldwide energy consumption has been profoundly reliant on fossil fuels which cause extreme environmental change therefore the investigation of new technologies to create effective sustainable energy source plays a significant role on the planet. The more the population rise in Malaysia, the more demand for electricity increases. Since fossil fuels are rampantly exploited to depletion in Malaysia, thereby looking into the need for alternative resources is vital. To diminish the dependency on fossil fuel resources, Pressure Retarded Osmosis (PRO) is an encouraging contender by utilising energy from the salinity gradient between fresh water and seawater. According to the economic expansion of membrane technologies and recent improvements in the technology, PRO has possibly sustainable preference and has been actively conducted demonstrations from lab-scale to pilot-scale

Exergy analysis of a high-temperature-steam-driven, varied-pressure, humidification–dehumidification system coupled with reverse osmosis

In this study, exergy analysis of a novel desalination system is presented and discussed. The water desalination is carried out using combined humidification–dehumidification and reverse osmosis technologies. Six system performance parameters are examined: overall exergetic efficiency, equivalent electricity consumption, specific exergy destruction, specific exergy lost, and total true specific exergy lost, as well as the exergy destruction ratios of the main components. The total true specific exergy lost is a new parameter presented in this study. It is a function of summation of total the exergy destruction rate and loss per total mass flow rate of the total pure water produced. This parameter is found to be a useful parameter to assess the exergetic performance of the system considered. By contrast, use of overall exergetic efficiency as an assessment tool can result in misleading conclusions for such a desalination system and, hence, is not recommended. Furthermore, this study reveals that the highest exergy destruction occurs in the thermal vapor compressor, which accounts for 50% of the total exergy destruction of the system considered. This study, in addition, demonstrates that the specific exergy destruction of the dehumidifier and TVC are the parameters that most strongly affect the performance of the system.Center for Clean Water and Clean Energy at MIT and KFUP

Thermal Desalination Systems: From Traditionality to Modernity and Development

As well known, the basic birthrights of human are the clean air, clean water, healthy food, and green energy. So, clean water is the second important requested need of all living organisms on Earth. To know the importance of water to our human bodies, a deficiency of just 2% in our body’s water supply indicates dehydration. Nowadays, all countries suffer from the problem of freshwater shortage. Despite the importance of clean water for our lives, only 0.01% is available as surface water such as the rivers, lakes, and swamps. These frightening facts have made it a national and humanitarian duty for scientists to research how to overcome the water problem and how to provide alternative sources of safe drinking water using renewable energies. Desalination is the most famous and operative technique used to overcome this problem. In this chapter, the different desalination techniques are reviewed and reported. Also, the solar distillation processes are mentioned with an extended review on the solar distillers. Besides, the application of artificial intelligence in improving the performance of desalination systems is reported. The main conclusions are stated at the end of this chapter

Low Carbon Desalination by Innovative Membrane Materials and Processes

Seawater and brackish water desalination has been a practical approach to mitigating the global fresh water scarcity. Current large-scale desalination installations worldwide can complementarily augment the global fresh water supplies, and their capacities are steadily increasing year-on-year. Despite substantial technological advance, desalination processes are deemed energy-intensive and considerable sources of CO2emission, leading to the urgent need for innovative low carbon desalination platforms. This paper provides a comprehensive review on innovations in membrane processes and membrane materials for low carbon desalination. In this paper, working principles, intrinsic attributes, technical challenges, and recent advances in membrane materials of the membrane-based desalination processes, exclusively including commercialised reverse osmosis (RO) and emerging forward osmosis (FO), membrane distillation (MD), electrodialysis (ED), and capacitive deionisation (CDI), are thoroughly analysed to shed light on the prospect of low carbon desalination

Biomass Processing for Biofuels, Bioenergy and Chemicals

Biomass can be used to produce renewable electricity, thermal energy, transportation fuels (biofuels), and high-value functional chemicals. As an energy source, biomass can be used either directly via combustion to produce heat or indirectly after it is converted to one of many forms of bioenergy and biofuel via thermochemical or biochemical pathways. The conversion of biomass can be achieved using various advanced methods, which are broadly classified into thermochemical conversion, biochemical conversion, electrochemical conversion, and so on. Advanced development technologies and processes are able to convert biomass into alternative energy sources in solid (e.g., charcoal, biochar, and RDF), liquid (biodiesel, algae biofuel, bioethanol, and pyrolysis and liquefaction bio-oils), and gaseous (e.g., biogas, syngas, and biohydrogen) forms. Because of the merits of biomass energy for environmental sustainability, biofuel and bioenergy technologies play a crucial role in renewable energy development and the replacement of chemicals by highly functional biomass. This book provides a comprehensive overview and in-depth technical research addressing recent progress in biomass conversion processes. It also covers studies on advanced techniques and methods for bioenergy and biofuel production

Development of thermo-responsive ionic liquid as draw solution and its performance in forward osmosis

Desalination based on membrane technology is one of the approaches which has been extensively explored to tackle the challenge in increasing demand of clean water. Although reverse osmosis (RO) process has been applied for a long time, the promising forward osmosis (FO) membrane desalination is viewed as a potentially viable energy efficient performance technology. But, the main problem in FO process is the lack of suitable draw solutes that can be efficiently regenerated. A distinct advantage using thermo-responsive ionic liquids (TRILs) is the efficient in regenerating the draw solute via thermally stimulation. In this study, 10 cations and two anions were selected from COSMO-RS database and van’t Hoff factor prediction. 11 type of ILs was successfully synthesized via metathesis and neutralization method. The synthesized ILs were mixed with water and were cooled to 0 °C and then gradually heated to 70 °C to screen critical temperature. When a solution was found to be phase-separated above its critical temperature, this mixture underwent the lower critical solution temperature (LCST) type phase transition and which contrary with upper critical solution temperature (UCST) behavioral. The interactions mechanism of TRILs with water were examined using COSMO-RS simulation and H NMR for selected ILs. The TRILs were tested in FO process as draw solution and achieved high water flux 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) (0.71 LMH) and tetrabutylphosphonium trifluoroacetate ([P4444][TFA]) (0.44 LMH) compared to NaCl (0.33 LMH). The [Bmim][BF4] was selected as draw solution and aquaporin membrane with pressure retarded osmosis (PRO) mode was used to evaluate the effect of parameter and optimal condition for FO process. The 2-Level factorial experiment design was used to study the effect of parameters such as feed and draw flowrate, draw solution concentration, temperature and type of flow with feed concentration using artificial seawater (0.6 M NaCl). The draw solution concentration and the interactions between draw and feed flowrate was the most significant factors to achieve high water flux 5.1 LMH. Besides that, the draw flowrate and the interaction of draw flowrate and feed flowrate give high significant negative effect which is good to obtain low reverse salt 1.3 gMH. The desirability function (DF) was used, in order to obtain the highest water flux 5.04 LMH and the lowest reverse salt flux 1.71 gMH with 0.95 desirability. The optimal condition for FO performance is 300 ml/min feed and draw flowrate with 3.0 M draw solution at 25 °C and co-current flow. In this research, the phase separation via thermally stimulated liquid -liquid phase separation was achievable. The traceable amount of [Bmim][BF4] in water rich phase was detected using UV-Vis spectroscopy and purified using nanofiltration (NF). The water spinach was selected to study the effect of traceable amount of ILs in water on plant growth and acceptable traceable amount of [Bmim][BF4] is below 500 ppm. Based on the findings, it can be concluded that, [Bmim][BF4] is alternatively suitable to be use as draw solution in FO process

Reverse electrodialysis: potential reduction in energy and emissions of desalination

Salinity gradient energy harvesting by reverse electrodialysis (RED) is a promising renewable source to decarbonize desalination. This work surveys the potential reduction in energy consumption and carbon emissions gained from RED integration in 20 medium-to-large-sized seawater reverse osmosis (SWRO) desalination plants spread worldwide. Using the validated RED system’s model from our research group, we quantified the grid mix share of the SWRO plant’s total energy demand and total emissions RED would abate (i) in its current state of development and (ii) if captured all salinity gradient exergy (SGE). Results indicate that more saline and warmer SWRO brines enhance RED’s net power density, yet source availability may restrain specific energy supply. If all SGE were harnessed, RED could supply ~40% of total desalination plants’ energy demand almost in all locations, yet energy conversion irreversibility and untapped SGE decline it to ~10%. RED integration in the most emission-intensive SWRO plants could relieve up to 1.95 kg CO2-eq m−3. Findings reveal that RED energy recovery from SWRO concentrate effluents could bring desalination sector sizeable energy and emissions savings provided future advancements bring RED technology closer to its thermodynamic limit.This research was funded by the LIFE programme (LIFE19 ENV/ES/000143) and the Spanish Ministry of Science, Innovation and Universities (RTI2018-093310-B-I00 and CTM2017-87850-R, and the FPI grant awarded to C.T., PRE2018-086454)