A CFD-DEM model simulated heat transfer between plastic and sand in a rotary furnace. • Loading solid heat carriers in the kiln can promote the heat transfer for pyrolysis. • The volatile residence time in the kiln increased with the loading of heat carriers. • Increasing the solid heat carrier loading could reduce the wax yield from ...
heat transfer calculations useful for estimating the effects of kiln design and operation on burden temperature. This pa-per presents a mathematical model of heat transfer in direct-ly-fired rotary kilns. The model uses one-dimensional zon-ing along the kiln axis with a mean beam length radiation model.
An improved heat transfer model has been developed for a direct-fired rotary kiln. The treatment of radiant heat transfer was based on the Reflection Method developed by Succec and applied by Gorog, and was extended to account for radiation from a flame. Some elements of the Resistive Network Method and Zone Method were incorporated in …
A series of experimental runs was carried out using the realistic but controlled arrangement of a pilot rotary kiln to obtain temperature data for the validation of a novel model that couples a computational fluid dynamics model of the flame to a granular bed model through heat transfer terms. The rotary kiln was 5.27 m long, with an internal ...
HEAT TRANSFER MODEL In our study case, the rotary kiln is approximated by a drum where heat is exchanged between different phases that will be defined below. The drum is a cylinder made in stainless steel with an inner diameter, DD a length, LD and a thickness, dD. The convective hot gas flows
The kiln length predicted by the present model is 5.74 m as compared to 5.5 m of the pilot kiln used in the experimental study of Watkinson and Brimacombe (1982, Watkinson, A.P. and Brimacombe, J ...
A model for rotary kiln heat transfer, which accounts for the interaction of all the transport paths and processes, is presented in a three-part series. In this first paper, the pilot kiln facility is described, and the significant results from the heat-transfer trials are …
Ginsberg and Modigell [64] selected the following heat transfer mechanisms for their model: the transfer between gases, the gas side wall and the …
This work analyzes the heat transfer conditions in a rotary kiln used for the heat treatment of iron ore pellets in the grate-kiln process. The analysis concerns conditions relevant to fuel switching from coal to hydrogen gas. A modeling assessment of the radiative heat transfer in the kiln is conducted including the pellet bed and inner kiln wall temperature …
rotary kiln. The model, which incorporates a detailed formulation of the radiative and convective heat-transfer coefficients in a kiln, has been employed to examine the effect of different kiln variables on both the regenerative and the overall heat transfer to the solids. The variables include rotational
K. E. Peray, The rotary cement kiln, Second Ed. Chemical Publishing, New York, USA (1986). Google Scholar A. A. Boateng and P. V. Barr, A thermal model for the rotary kiln including heat transfer within the bed, International Journal of Heat and Mass Transfer, 39 (1996) 2131–2147.
radiative heat transfer from particles and gases, as well as convective and conductive heat transfer are all examined in an in-house modeling tool of rotary kilns. …
Rotary kilns are used ubiquitously in the chemical and metallurgical industries. The mechanism of heat transfer in a rotary kiln is discussed in this paper, in which the effect of rotation is considered in determining heat transfer coefficients. In particular, an extended penetration theory is successfully developed to describe the …
Differences between the published and most rotary cement kilns, like the decomposition rate of kiln feed, were considered, and the data of a 2 500 t/d rotary cement kiln in China was accumulated ...
2.2. Heat Transfer Model. The rotary kiln modeling tool used within this work has been developed in our previous work based on a full-scale kiln17 and a pilot-scale kiln.18 The model describes the heat transfer within the kiln, to the kiln inner surfaces, and to the pellet bed material, including radiation
A one-dimensional axial heat transfer model for an internally heated rotary kiln has been developed. Both predicted temperature profiles and heat transfer …
Radiative Heat Transfer in Rotary Kilns J. P. GOROG, J. K. BRIMACOMBE, AND T. N. ADAMS ... amongst the gas, solids, and wall of a rotary kiln, and to develop a radiation model based on real-gas behavior. The study may be divided into three sections: i) The radiative characterization of the freeboard gas, ...
This work discusses the development and use of a detailed 3D radiative heat transfer model of a rotary kiln with a present bed material, used for iron ore pelletizing.
A three-dimensional steady-state model to predict the flow and heat transfer in a rotary lime kiln is presented. All important phenomena are considered for the pre-heat and calcination zones including turbulent gas flow, buoyancy, all modes of heat transfer, evolution and combustion of species and granular bed motion with calcination …
In the rotary kiln, the motion of particles determines the efficiency of heat and mass transfer (Demagh et al., 2012; Oleena, 2018; Yin et al., 2014). Shen (2014) investigated the effects of rotating velocity, filling rate, number of lifting plates and the size of particle on the motion of the particles.
A model for rotary kiln heat transfer, which accounts for the interaction of all the transport paths and processes, is presented in a three-part series. In this first paper, the pilot kiln facility is described, and the significant results from the heat-transfer trials are identified. Limestone, Ottawa sand, and pctroleum coke were heated using a range of firing rates, …
The heat transfer from the surface of the rotary kiln to the environment takes place via both radiation and conduction. Rayleigh (Ra D) and Nusselt (Nu D) numbers, needed to calculate the heat transfer coefficient by conduction for the heat transfer from the surface of the rotary kiln, have been found as 30.16 × 10 7 and …
This work discusses the development and use of a detailed 3D radiative heat transfer model of a rotary kiln with a present bed material, used for iron ore pelletizing. A discrete ordinates method is used to solve the radiative heat transfer equation with radiative properties calculated using a weighted-sum-of-grey-gases (WSGG) model for …
The heat transfer coefficient in this rotary kiln is discussed in order to guide the engineering design. Due to the complexity of the particle motion and heat transfer process in the rotary kiln, the overall volumetric heat transfer coefficient was mostly used (Alqahtani, Alenazy, & Pandiaraj, 2020; Ding, Lu, Chen, He, & Ou, 2011).
The heat transfer coefficient and the effective heat transfer area are the two key factors for optimizing the heat transfer model of rotary kiln, which have attracted much attention from researchers. Previous experimental studies have shown that the heat transfer in the rotary kiln is attributed to six mechanisms as shown in Fig. 1, including ...
complexity in the rotary kiln processes. Hence, for safe design ... models for the contact heat transfer in rotary kilns was provided by Li et al. [7]. Furthermore, a simplified model for the contact heat transfer based on [11] was developed. EXPERIMENTS Experimental Setup and Test Materials
The two-fluid model and the granular flow theory were combined with the heat transfer model and used to simulate a rotary kiln. The heat transfer and mixing characteristics in the two-dimensional cross-section were investigated by numerical simulation to analyze the influence of certain factors on the heat transfer.
An analytical one-dimensional model was developed to predict the effect of the different kiln variables on the regenerative heat transfer by the wall in a rotary kiln. The basis of this model is … Expand
The lime rotary kiln system uses the entropy and grey correlation model, combining the lime rotary kiln operation process to determine the input and output …
Based on the analysis of heat transfer mechanisms, a one-dimensional axial heat transfer model for an internally heated rotary kiln is presented. The theoretical predictions and empirical equations of the heat transfer …
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نشانی: شماره 1688، جاده شرقی گاوک، منطقه جدید پودونگ، شانگهای، چین.
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