Experimentally Validated Numerical Modeling of Heat Transfer in Granular Flow in Rotating Vessels
Experimentally Validated Numerical Modeling of Heat Transfer in Granular Flow in Rotating Vessels
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DOI：
10.5772/13536
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发表时间：
2011-02
期刊：
影响因子：
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通讯作者：
B. Chaudhuri;F. Muzzio;M. Tomassone
中科院分区：
文献类型：
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作者：
B. Chaudhuri;F. Muzzio;M. Tomassone
颗粒物料中的传热是自然界中普遍存在的现象，影响着从多相反应器到窑炉和煅烧炉的大量应用。在这些类型的应用中使用的材料通常以颗粒形式处理和存储，例如催化剂颗粒，煤，塑料颗粒，金属矿石，食品，矿物精矿，洗涤剂，肥料和许多其他干湿化学品。通常，这些材料需要在加工前或加工过程中加热和冷却。旋转煅烧炉是冶金和催化剂工业中最常用的混合设备（Lee, 1984； Lekhal等人，2001）。它们是长而近水平的旋转鼓，可以配备内部飞行（挡板）来处理各种类型的原料。双锥浸渍剂用于将金属或其他组分掺入多孔载体颗粒中，同时开发负载催化剂。随后，浸渍催化剂被加热、干燥并在旋转煅烧炉中反应，以获得所需的最终形式。在这些过程中，热量通常在固体表面和相对于表面运动的颗粒之间通过传导和对流传递。在过去的五十年中，人们一直对系统参数的作用以及流化床中颗粒介质和边界表面之间的传热机制感兴趣（Mickey & Fairbanks, 1955; Basakov, 1964; Zeigler & Agarwal, 1969； Leong等）。, 2001;Barletta等人，2005年)，密相溜槽，漏斗和填充床（Schotte， 1960年；Sullivan & Sabersky， 1975年；Broughton & Kubie， 1976年；Spelt等人，1982年；Patton等人，1987年；Buonanno & Carotenuto， 1996年；Thomas等人，1998年；Cheng等人，1999年），干燥器和旋转反应器和窑（Wes等人，1976年；Lehmberg等人，1977年）。最近，LePage等人于1998年报道了流化床煅烧炉和旋转煅烧炉/窑炉的实验工作；斯普林出版社。2000年和Sudah。Et al., 2002。在许多这样的研究中，已经提出了床层温度与一系列操作变量的表面传热系数的经验相关性。这种相关性的有效性是有限的，因为它们不能很容易地推广到不同的设备几何形状，并且在研究变量的实验范围之外推断它们的使用是有风险的。此外，这些模型中的大多数都没有捕捉到粒子表面的相互作用或材料的详细微观结构
Heat transfer in particulate materials is a ubiquitous phenomenon in nature, affecting a great number of applications ranging from multi-phase reactors to kilns and calciners. The materials used in these type of applications are typically handled and stored in granular form, such as catalyst particles, coal, plastic pellets, metal ores, food products, mineral concentrates, detergents, fertilizers and many other dry and wet chemicals. Oftentimes, these materials need to be heated and cooled prior to or during processing. Rotary calciners are most commonly used mixing devices used in metallurgical and catalyst industries (Lee, 1984; Lekhal et. al., 2001). They are long and nearly horizontal rotating drums that can be equipped with internal flights (baffles) to process various types of feedstock. Double cone impregnators are utilized to incorporate metals or other components into porous carrier particles while developing supported catalysts. Subsequently, the impregnated catalysts are heated, dried and reacted in rotating calciners to achieve the desired final form. In these processes, heat is generally transferred by conduction and convection between a solid surface and particles that move relative to the surface. Over the last fifty years, there has been a continued interest in the role of system parameters and in the mechanisms of heat transfer between granular media and the boundary surfaces in fluidized beds (Mickey & Fairbanks, 1955; Basakov, 1964; Zeigler & Agarwal, 1969; Leong et.al., 2001; Barletta et. al., 2005), dense phase chutes, hoppers and packed beds (Schotte, 1960; Sullivan & Sabersky, 1975; Broughton & Kubie, 1976; Spelt et. al., 1982; Patton et. al., 1987; Buonanno & Carotenuto, 1996; Thomas et. al., 1998; Cheng et. al., 1999), dryers and rotary reactors and kilns (Wes et. al., 1976; Lehmberg et. al., 1977). More recently, experimental work on fluidized bed calciner and rotary calciners/kilns have been reported by LePage et.al, 1998; Spurling et.al., 2000, and Sudah. et al., 2002. In many of these studies, empirical correlations relating bed temperature to surface heat transfer coefficients for a range of operating variables have been proposed. Such correlations are of restricted validity because they cannot be easily generalized to different equipment geometries and it is risky to extrapolate their use outside the experimental range of variables studied. Moreover, most of these models do not capture particle-surface interactions or the detailed microstructure of the