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1.
《International Journal of Hydrogen Energy》2022,47(62):25880-25898
Hydrogen as an energy carrier can play a significant role in reducing environmental emissions if it is produced from renewable energy resources. This research aims to assess hydrogen production from wind energy considering environmental, economic, and technical aspect for the East Azerbaijan province of Iran. The economic assessment is performed by calculation of payback period, levelized cost of hydrogen, and levelized cost of electricity. Since uncertainty in the power output of wind turbines may affect the payback period, all calculations are performed for four different turbine degradation rates. While it is common in the literature to choose the wind turbine based on a single criterion, this study implements Multi-Criteria Decision-Making (MCDM) techniques for this purpose. The results of Step-wise Weight Assessment Ratio Analysis illustrates that economic issue is the most important criterion for this research. The results of Weighted Aggregated Sum Product Assessment shows that Vestas V52 is the most suitable wind turbine for Ahar and Sarab cities, while Eovent EVA120 H-Darrieus is a better choice for other stations. The most suitable location for wind power generation is found to be Ahar, where it is estimated to annually generate 2914.8 kWh of electricity at the price of 0.045 $/kWh, and 47.2 tons of hydrogen at the price of 1.38 $/kg, which result in 583 tons of CO2 emission reduction. 相似文献
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Yu. A. Radin I. A. Grishin T. S. Kontorovich O. B. Panshina A. V. Chugin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(2):113-119
Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of
flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problems exist for two-boiler single-turbine
units of type PGU-325 and for two-boiler single-turbine units of traditional steampower plants with an output of 200–300 MW
upon connection of the second furnace of a two-furnace boiler to the operating first furnace. Analysis of the temperature-induced
stressed state and of the cyclic strength of thick-walled elements of the steam-water conduit of PGU-450 and of two-furnace
boilers of two-boiler single-turbine units with an output of 200–300 MW (the check valve, the inlet header of the water economizer)
is used for determining the steam temperature differences in the high-pressure conduits to the steam turbine and the order
of connection of the second exhaust-heat boiler to the operating fist one. Modes of enabling a two-boiler single-turbine unit
of a combined-cycle plant, which are most “rigid” from the standpoint of thermal strength, are determined.
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Translated from élektricheskie Stantsii, No. 2, February 2006, pp. 11–17. 相似文献
4.
This paper presents a summary of the mechanical features and the medium term operating experience from three small horizontal axis wind energy conversion systems covering a range of 500 to 5000 Watt, intented for rural and isolated communities. These turbines have a new regulator which reduces gyroscopic loads, is easy to adjust and could be manufactured stronger and in smaller sizes than the conventional tail vanes. It is concluded that is feasible to build cheaps and reliable wind turbine generators with an acceptable efficiency employing common-use elements, but is needed a careful and optimized design. 相似文献
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用废旧橡胶生产精细胶粉的空气涡轮制冷低温粉碎法 总被引:1,自引:0,他引:1
利用先进的空气涡轮制冷系统,在低温条件下,将废旧橡胶进行冷冻,粉碎,制成60目以上细度的精细胶粉,此法简称ATCG法,它的冷冻能耗成本仅为国际上通用的液氮法的十分之一,整个工艺过程不产生二次污染,为精细胶粉的制取开辟了一条新途径。 相似文献
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从汽轮机回热系统的实际情况出发,运用非线性规划理论和计算机技术,解决了给水焓升设计中的最优分配问题。结合具体实例,针对国产200MW汽轮机回热系统给水焓升的分配进行了说明。 相似文献
9.
介绍了未来航空涡轮发动机对润滑油性能的要求:在260,-54℃时,试样运动黏度分别大于1.0 mm2/s和小于15 000 mm2/s,热氧化安定性温度为260~427℃。该要求已超出了目前使用的酯类润滑油所能承受的最大极限。为了满足要求,需开发全氟聚醚、改性硅油、聚苯醚、C-型醚、氟醚三嗪及环三磷偶氮润滑油基础油,它们的使用温度依次为:-34~316,-60~260,5~288,-29~260,-30~343,-15~343℃。 相似文献
10.
介绍了汽轮机数字电液控制系统(DEH)的硬件组成,着重论述了DEH的控制原理和控制过程。结合天津碱厂新建4^#机组,与前3台机组的液压控制调节方式进行比较,突出了DEH控制的优势。对DEH系统的软件作了介绍。同时对DEH的控制系统Foxboro I/A Series的系统软件和系统网络作了较详细的论述。最后,讨论了运行中可能出现的问题和解决方法。 相似文献