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991.
992.
993.
Chemical looping combustion (CLC) is a clean and efficient flame-free combustion technology,which combust the fuels by lattice oxygen from a solid oxygen carrier with inherent CO2 capture.The develop-ment of oxygen carriers with low cost and high redox performance is crucial to the whole efficiency of CLC process.As the solid by-product from the sulfuric acid production,pyrite cinder presented excellent redox performance as an oxygen carrier in CLC process.The main components in pyrite cinder are Fe2O3,CaSO4,Al2O3 and SiO2 in which Fe2O3 is the active component to provide lattice oxygen.In order to sys-tematic investigate the functions of supports (CaSO4,Al2O3 and SiO2) in pyrite cinder,three oxygen car-riers (Fe2O3-CaSO4,Fe2O3-Al2O3 and Fe2O3-SiO2) were prepared and evaluated in this study.The results showed that Fe2O3-CaSO4 displayed high redox activity and cycling stability in the multiple redox cycles.However,both Fe2O3-Al2O3 and Fe2O3-SiO2 experienced serious deactivation during redox reactions.It indicated that the inert Fe-Si solid solution (Fe2SiO4) was formed in the spent Fe2O3-SiO2 sample,which decreased the oxygen carrying capacity of this sample.The XPS results showed that the oxygen species on the surface of Fe2O3-CaSO4 could be fully recovered after the 20 redox cycles.It can be concluded that CaSO4 is the key to the high redox activity and cycling stability of pyrite cinder. 相似文献
994.
Cinkilic Emre Moodispaw Michael Zhang Jianyue Miao Jiashi Luo Alan A. 《Metallurgical and Materials Transactions A》2022,53(8):2861-2873
Metallurgical and Materials Transactions A - The use of secondary aluminum for structural components in the automotive industry is limited by the high Fe contents in recycled alloys which often... 相似文献
995.
996.
Zhang Hongtao Cai Minghui Zhu Wanjun Sun Shenghui Yan Haile Yao Shengjie Luan Yikun Tang Shuai Hodgson P. D. 《Metallurgical and Materials Transactions A》2022,53(11):3869-3880
Metallurgical and Materials Transactions A - A cold-rolled low Al-added medium Mn steel was employed to investigate the low-temperature superplastic deformation at a relatively high initial strain... 相似文献
997.
Zhang Jingfan Meng Lei Zhang Deliang Gao Wenpeng Fang Gongjun Luo Junjie Chen Wen 《Metallurgical and Materials Transactions A》2022,53(11):4126-4138
Metallurgical and Materials Transactions A - Two heat treatments, namely 955°C/2h/AC (AC = air cooling) and 955°C/4h/FC (FC = furnace cooling), were carried out on... 相似文献
998.
The characterization of La
x
Sr1−x
MnO3 powders produced by spray pyrolysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation,
specific surface area (Brunauer-Emett-Teller), and particle size distribution measurements shows that the resultant large
particles are loose agglomerates consisting of many small particles. However, the sintered tiny particles can form hard agglomerates,
and the particle size increases remarkably. The structures of the powders before and after sintering were identified by x-ray
diffraction (XRD). The study of the electrical property of the powder shows that the powder is a metallic conductor. In a
reducing atmosphere, the powder can be decomposed. When the powder is cofired with yttria-stabilized zirconia 5% (YSZ) powder
at 1200 °C for 5 h, no new phase is produced, and the powder remains a single provskite hexagonal-rhombohedral structure. 相似文献
999.
1000.
针对某黄金生产企业含砷氰化尾矿污染特征,开展了搅拌洗涤法、臭氧氧化法、酸化溶砷法、铁盐固砷法等多种无害化方法联合处理试验研究,旨在将该含砷氰化尾矿处理至满足氰渣规范回填利用污染控制要求。结果表明:该含砷氰化尾矿回填利用污染控制技术工艺为压滤调浆搅拌洗涤+臭氧氧化+酸化溶砷+铁盐固砷,最佳参数为原矿浆压滤后加水调浆,矿浆浓度40%,臭氧投加量0.66 g/L,酸化溶砷pH值3、曝气量0.1 m3/h、反应时间2 h,铁盐固砷七水合硫酸亚铁投加量20.0 g/L、反应时间1 h。研究结果为该黄金生产企业含砷氰化尾矿回填利用提供了技术支撑。 相似文献