College of Agricultural Engineering, Al-Azhar University, Cairo, 11765, Egypt.
Sci Rep. 2022 Jul 22;12(1):12572. doi: 10.1038/s41598-022-16171-w.
Microwave pyrolysis of corn stover has been optimized by Response surface methodology under different microwave power (500, 700, and 900 W) and three ratios of activated carbon additive (10, 15, and 20%) for obtaining maximum bio-oil yield followed by biochar. The optimal result has been evaluated and the environmental and techno-economic impacts of using solar-powered microwave heating have been tested. The optimal pyrolysis condition found to be 700 W microwave power and 10% of activated carbon. The yields of both bio-oil and biochar were about 74 wt% under optimal condition. The higher heat values of 26 MJ/kg and 16 MJ/kg were respectively achieved for biochar and bio-oil. The major components of bio-oil were hydrocarbons (36%) and phenols (28%) with low oxygen-containing compounds (2%) and acids (2%). Using the solar-powered system, 20,549 tonnes of CO can be mitigated over the lifetime of the set-up, resulting in USD 51,373 in carbon credit earnings, compared to 16,875 tonnes of CO mitigation and USD 42,167 in carbon credit earnings from a grid electricity system. The payback periods for solar-powered and grid-connected electrical systems are estimated to be 1.6 and 0.5 years, respectively, based on biochar and bio-oil income of USD 39,700 and USD 45,400.
采用响应面法，在不同微波功率（500、700 和 900 W）和三种活性炭添加剂比例（10%、15%和 20%）下对玉米秸秆进行微波热解，优化了微波热解条件，以获得最大的生物油产率，随后是生物炭。对最佳结果进行了评估，并测试了使用太阳能微波加热的环境和技术经济影响。发现最佳的热解条件为 700 W 微波功率和 10%的活性炭。在最佳条件下，生物油和生物炭的产率约为 74 wt%。生物炭和生物油的高热值分别达到 26 MJ/kg 和 16 MJ/kg。生物油的主要成分是烃类（36%）和酚类（28%），含氧化合物（2%）和酸类（2%）含量较低。使用太阳能系统，在装置的使用寿命内可以减少 20549 吨 CO，产生 51373 美元的碳信用收益，而使用电网电力系统可以减少 16875 吨 CO 和产生 42167 美元的碳信用收益。基于生物炭和生物油收入分别为 39700 美元和 45400 美元，太阳能和并网电力系统的投资回收期估计分别为 1.6 年和 0.5 年。
