Combustion and reaction

Flow Properties of Entrained Flow Gasifier Fine Slag and Network Structure of its Molten Slag

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  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China

Online published: 2023-10-24

Supported by

This work was financially supported by Class A Strategic Pilot Science and Technology Project, Chinese Academy of Sciences (Grant No. XDA21040602), the National Natural Science Foundation of China (Grant No. U1810127) and the Youth Innovation Promotion Association, Chinese Academy of Science (Grant No. Y201932).

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

Abstract

The entrained flow gasification has been identified as the most promising gasification technology. Serious environmental pollution and waste of land resources are caused by the increasing amount of storage and production of coal gasification slag. The aim of this work is to explore the feasibility of high-temperature combustion and melting technology for treating coal gasification fine slag and determine the important parameters of system operation. The flow properties and molten slag structure characteristics of three fine slags from different entrained flow gasifiers were studied. Depending on the melting mechanism of melt-dissolution, the melting time of fine slags is short. Three fine slags all produce glassy slags, which is conducive to slag discharge. The degree of polymerization of silicate melt is proportionate to the amount of SiO2 in the slag. A part of Al3+ exist in the form of [AlO4]5– because of the effect of CaO and Na2O, as the network former. Finally, the degree of polymerization of the three type molten slag was calculated by considering the role of Si and Al in molten slag and the property of each one.

Cite this article

ZHOU Li, REN Qiangqiang, YANG Guiyun, XU Jing, LI Wei . Flow Properties of Entrained Flow Gasifier Fine Slag and Network Structure of its Molten Slag[J]. Journal of Thermal Science, 2023 , 32(5) : 1878 -1888 . DOI: 10.1007/s11630-023-1874-z

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