文献类型：期刊文献

英文题名：Rheological properties of coal ash slag at ultra-high temperatures

作者：Song, Wenjia[1]; Zhu, Zibin[1]

机构：[1] The State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, China

年份：2013

起止页码：157

外文期刊名：Rheology: Theory, Properties and Practical Applications

收录：EI(收录号：20182705477083)

语种：英文

外文关键词：Non Newtonian flow - Temperature distribution - Coal combustion - Yield stress - Slags - Coal ash - Rheology - Deposition - Newtonian liquids - Greenhouse gases - Gasification - Shear thinning

摘要：The integration gasification combined cycle is one of the leading options for power generation that limit the amount of greenhouse gas through carbon capture and storage. Ash-related problems (i.e., slagging and fouling of ash deposition on the furnace wall and tubes in the conversion section) are often the main reason for entrained-flow gasifiers in the integration gasification combined cycle and boilers in oxy-fuel combustion unscheduled shut downs. Thus, understanding the high-temperature physical properties of molten coal ash slag may enable an accurate description of the condition of ash deposition in the gasifier and boiler. The results of a series of high-temperature experiments undertaken to investigate the rheological characteristics of molten coal ash slag are reported. Firstly, the viscosities of 45 coal ash slag samples at high temperature have been measured under different temperatures and shear rates. The computer thermodynamic software package FactSage has been used to predict liquidus temperatures, volume fractions of crystallized solid particles (φ ), and the compositions of remaining liquid phase for 45 coal ash slag samples. The flow properties of completely liquid and partly crystallized coal ash slag samples have been predicted by three viscosity models. The Urbain formalism has been modified to describe the viscosities of fully liquid slag and homogeneous remaining liquid phase in coal ash slag samples. The modified Einstein equation and Einstein-Roscoe equation have been used to describe the viscosities of heterogeneous coal ash slag samples of φ ? 2014 by Nova Science Publishers, Inc. All rights reserved.