Abstract In this study, Stigonematales sp. microalgae were collected from drain water and characterized for its' morphological edifice, elemental composition, thermal condition and energy generation capacity by using scanning electron microscopy, energy dispersive X-ray, thermogravimetric analyzer and bomb calorimeter, respectively. Scanning electron micrographs revealed the top view of microalgae and ash pellet with carbon coated specimens at low voltage (5.0 kV) through the secondary electron image detector. Elemental analysis revealed all the major and minor constituents of this microalgae species and its' ash in terms of dry weight (%) and atomic weight (%). Thermogravimetric analysis was conducted at heating rate, 10 °C/min and this experimental results determined moisture content, volatile matter, ash content and fixed carbon of the sample with 4.5%, 35%, 39.5% and 21%, respectively. Microalgae powder blended with bituminous coal by 75%, 50% and 25% measured calorific value 14.07 MJ/kg, 19.88 MJ/kg and 26.42 MJ/kg, respectively. Microalgae (75%) -coal (25%) blend showed excellent amount of energy content, 24.59 MJ/kg. Microalgae blended with coal unveiled an outstanding outcome with elevation of the volatile matter and drop of the ash content. Optimization of microalgae-coal blend in large-scale application can initiate bright future in renewable energy exploration.

中文翻译：

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来自排水的混合微藻物种的元素、形态和热分析

摘要在这项研究中，Stigonematales sp。采用扫描电子显微镜、能量色散X射线、热重分析仪和弹式量热仪对微藻的形态结构、元素组成、热条件和能量产生能力进行了表征。扫描电子显微照片通过二次电子图像检测器在低电压 (5.0 kV) 下显示了微藻和灰粒与碳涂层样品的俯视图。元素分析揭示了该微藻物种及其灰分的干重 (%) 和原子量 (%) 的所有主要和次要成分。以 10 °C/min 的加热速率进行热重分析，该实验结果确定了水分含量、挥发分、样品的灰分和固定碳分别为 4.5%、35%、39.5% 和 21%。微藻粉与烟煤混合75%、50%和25%测得的热值分别为14.07 MJ/kg、19.88 MJ/kg和26.42 MJ/kg。微藻 (75%) - 煤 (25%) 混合物显示出极好的能量含量，24.59 MJ/kg。微藻与煤混合后，挥发分升高，灰分下降，效果显着。在大规模应用中优化微藻-煤混合物可以开启可再生能源勘探的光明前景。59 兆焦耳/公斤。微藻与煤混合后，挥发分升高，灰分下降，效果显着。在大规模应用中优化微藻-煤混合物可以开启可再生能源勘探的光明前景。59 兆焦耳/公斤。微藻与煤混合后，挥发分升高，灰分下降，效果显着。在大规模应用中优化微藻-煤混合物可以开启可再生能源勘探的光明前景。