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排序方式: 共有2770条查询结果,搜索用时 31 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(43):18831-18856
This study represents the results of the analysis and optimization of an integrated system for cogenerating electricity and freshwater. This setup consists of a Solid Oxide Fuel cell (SOFC) for producing electricity. Unburned fuel of the SOFC is burned in the afterburner to increase the temperature of the SOFC's outlet gasses and operate a Gas turbine (GT) to produce additional power and operate the air compressor. At the bottom of this cycle, a combined setup of a Multi-Effect Desalination (MED) and Reverse Osmosis (RO) is considered to produce freshwater from the unused heat capacity of the GT's exhaust gasses. Also, a Stirling engine is used in the fuel supply line to increase the fuel's temperature. Using LNG and the Stirling engine will replace the fuel compressor with a pump which increases the system performance and eliminates the need for the expansion valve. To study the system performance a mathematical model is developed in Engineering Equation Solver (EES) program. Then, the system's simulated data from the EES has been sent to MATLAB to promote the best operating condition based on the optimization criteria. An energetic, exergetic, economic, and environmental analysis has been performed and a Non-dominated Sorting Genetic Algorithm (NSGA-II) is used to achieve the goal. The two-objective optimization is performed to maximize the exergetic efficiency of the proposed system while minimizing the system's total cost of production. This cost is a weighted distribution of the Levelized Cost of Electricity (LCOE) and Levelized Cost of freshwater (LCOW). The results showed that the exergetic and energetic efficiencies of the system can reach 73.5% and 69.06% at the optimum point. The total electricity production of the system is 99 MW. The production cost is 11.71 Cents/kWh, of which 1.04 Cents/kWh is emission-related and environmental taxes. The freshwater production rate is 42.44 kg/s which costs 4.38 USD/m3. 相似文献
2.
The corrosion behavior and mechanism of iron‐oxidizing bacteria (IOB) on X65 steel in seawater are studied. This study uses the methods of weight loss, electrochemical measurements, and surface analysis. The results show that the IOB increases the corrosion damage degree of steel. Pittings are observed in the medium with IOB. The potentiodynamic polarization curves show that the anodic reaction rate is accelerated in the corrosion process of IOB. The synergies in corrosion between the metal surface, abiotic corrosion products, and bacterial cells, and the pitting corrosion mechanism of X65 steel are discussed. 相似文献
3.
作为一种环保节能的新兴脱盐技术,电容去离子技术正在成为替代反渗透脱盐和电渗析脱盐的一项重要的脱盐技术。各种碳基材料被广泛地应用于电容去离子电极材料的研究,然而大多数碳基材料为粉末状材料,需要添加黏结剂,这必将导致电极材料电吸附能力的下降。利用静电纺丝技术,将ZIF纳米颗粒和聚丙烯腈混纺,并通过分段高温热处理过程,成功合成了具有柔性结构的整体性多孔碳纳米纤维。由于其具有孔道结构的分级分布和较强的亲水性等优良特性,所制得的多孔碳纳米纤维在1.2 V电压下于500 mg/L NaCl溶液中表现出良好的电吸附性能,脱盐量达到了19.92 mg/g,比普通碳纳米纤维提高了一倍以上。 相似文献
4.
5.
《International Journal of Hydrogen Energy》2020,45(27):13876-13883
In this study, marine microalgae Chlorella pyrenoidosa produced 186 ml H2/l under nitrogen deprivation in natural seawater, and adding 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) to medium reduced the total volume of hydrogen production by 85%. This suggested water was the main electron donor for hydrogenase. An active starch accumulation was observed during the first two days in nitrogen deprivation. But the starch content in cell decreased only by 7% at the end of the hydrogen evolution stage. This was shown the absence of a large contribution of starch to the hydrogen production by C. pyrenoidosa in nitrogen deprivation. Different from the hydrogen production by Chlamydomonas reinhardtii under sulfur deprivation condition, the concentration of acetate in the medium decreased not only at the stage of oxygen consumption but also during the stage of hydrogen evolution by C. pyrenoidosa. Thus, acetate is involved not only in the establishment of anaerobiosis but also plays an important role in the production of hydrogen by C. pyrenoidosa as an exogenous electron donor. 相似文献
6.
The feasibility of using 2304 duplex stainless steel rebar in seawater concrete was determined by studying the passivation and corrosion behavior of steel in solutions simulated curing and service stage of concrete, respectively. The results demonstrate that 2304 duplex stainless steel rebar could be used with seawater concrete because of a stable passive film formed on the steel surface during the curing stage of concrete even in the presence of 2 M chloride ions. However, due to the synergistic effect of concrete carbonation, the rebar suffered a corrosive attack by chloride due to the lack of OH? inhibition. 相似文献
7.
设计开发一种具有高通量、低流阻特征的空心锥喷嘴,并通过理论与实验方法研究空心锥喷嘴的喷淋性能,基于准自由涡理论建立空心锥喷嘴内部流体流动的数学模型,阐明流量系数、喷淋锥角、喷嘴流量与喷嘴结构参数之间的定量关系,并利用多效蒸馏海水淡化喷淋实验台对理论计算结果进行实验测试和验证。研究结果表明:正常工作状态下喷嘴流量系数、喷淋锥角、喷淋流量等参数理论值与测量值之间的误差小于5%,验证了设计模型的准确性。同时根据实验测试数据,拟合得到该类型空心锥喷嘴喷淋锥角与雷诺数之间的经验公式,可为蒸馏海水淡化用大流量空心锥喷嘴的结构设计、工艺选型提供理论指导和数据支持。 相似文献
8.
9.
Camden Debruler Wenda Wu Kevin Cox Brice Vanness T. Leo Liu 《Advanced functional materials》2020,30(24)
Here, a pH neutral aqueous organic redox flow battery (AORFB) consisting of three electrolytes channels (i.e., an anolyte channel, a catholyte channel, and a central salt water channel) to achieve integrated energy storage and desalination is reported. Employing a low cost, chemically stable methyl viologen (MV) anolyte, and sodium ferrocyanide catholyte, this desalination AORFB is capable of desalinating simulated seawater (0.56 m NaCl) down to 0.023 m salt concentration at an energy cost of 2.4 W h L?1 of fresh water—competitive with current reverse osmosis technologies. Simultaneously, the cell delivers stored energy at 79.7% efficiency with a cell voltage of 0.85 V. Furthermore, the cell is also capable of higher current operation up to 15 mA cm?2, providing 4.55 mL of fresh water per hour. Combining energy storage and water desalination into such a bifunctional device offers the opportunity to address two growing global issues from one hardware installation. 相似文献
10.
High-performance polymers for water desalination were designed. A novel polysulfone was prepared via reaction between a new synthesized pyridine-based diol and bis(4-fluorophenyl) sulfone. Also a series of disulfonated copolymers with sulfonation content of 20–50 wt% were prepared to compare the hydrophilicity with the pristine polymer. The generated membranes were characterized by microscopic, mechanical, and thermal methods, and the influence of sulfonation degree on hydrophilicity, water flux, and salt rejection was followed. Water flux of sulfonated membranes was increased compare to pristine membrane as sulfonation increased, while the salt rejection decreased. Optimum application performance was obtained for membrane with 30 wt% sulfonation content. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48568. 相似文献