The Experts below are selected from a list of 9429 Experts worldwide ranked by ideXlab platform
Akwasi A Boateng - One of the best experts on this subject based on the ideXlab platform.
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Rotary Kiln Environmental Applications
Rotary Kilns, 2020Co-Authors: Akwasi A BoatengAbstract:Owing to its design and intense thermal processing capabilities, the Rotary Kiln has been an industrial workhorse for the thermal destruction of hazardous waste. When properly operated, Kilns can achieve over 99.99% destruction efficiency of some very toxic materials including chlorinated compounds. They are therefore permitted by environmental agencies throughout the world to carry out this important function without harmful emissions to the atmosphere. This chapter introduces the reader to the technical basics of the US environmental regulations that are applicable when an industrial Rotary Kiln is permitted to burn hazardous waste for energy recovery.
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The Rotary Kiln Evolution and Phenomenon
Rotary Kilns, 2020Co-Authors: Akwasi A BoatengAbstract:Publisher Summary This chapter provides an introduction to Rotary Kilns as an alternative to other unit operation devices. The history and evolution of the Rotary Kiln and some processes that have found applications over the years are presented. The design and operation of Rotary Kilns have undergone a systematic evolution since the days of the ancient Egyptians. Improvements include reduced labor, increased productivity, mixing, heat transfer, and product quality. Currently, Rotary Kilns are employed by industry to carry out a wide array of material processing operations, for example, reduction of oxide ore, reclamation of hydrated lime, calcining of petroleum coke, and hazardous waste reclamation. A quantitative understanding of the transport phenomena underlying the Rotary Kiln is presented. Several Rotary Kiln designs have evolved, each specific to the process application it is intended for. Mineral processing Kilns are classified as vertical, horizontal, or other miscellaneous mixed types. They also come in several forms and shapes. In spite of the distinctions, most Kilns, vertical or horizontal, when used for thermal processing in a continuous operation will have distinct zones along their axial length.
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1 – The Rotary Kiln Evolution and Phenomenon
Rotary Kilns, 2020Co-Authors: Akwasi A BoatengAbstract:This chapter introduces the reader to Rotary Kilns as an alternative to other unit operation devices. Here, the history and evolution of the Rotary Kiln and some processes that have found applications over the years are presented.
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Rotary Kiln Minerals Process Applications
Rotary Kilns, 2020Co-Authors: Akwasi A BoatengAbstract:The processes that employ the Rotary Kiln as the primary reactor are many and they encompass all industries including food, dedicated dryers, and mineral processing. Herein we focus on minerals and materials processing and provide some of the key industrial processes that use a Rotary Kiln as the primary workhorse. We start with the cement and lime processes and then move on to describe some of the carbothermic reduction processes that employ the Rotary Kiln as the primary device where we examine two processes, iron ore reduction (the SL/RN (acronym for steel-making companies Stelco, Lurgi, and Republic National) process) and ilmenite ore reduction (the Becher process). We then examine the lightweight aggregate process and finally finish the chapter with a case study on biomass carbonization or pyrolysis/torrefaction at low temperatures.
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10 – Rotary Kiln Minerals Process Applications
Rotary Kilns, 2020Co-Authors: Akwasi A BoatengAbstract:Publisher Summary From the fuel requirement point of view, Rotary Kilns are the most flexible of all lime Kilns. They are successfully fired with natural gas, fuel oil, and pulverized fuels of all types including coal, coke, and sawdust. There are many processes that employ the Rotary Kiln as the primary reactor, encompassing all industries including food, dedicated dryers, minerals processing, etc. This chapter focuses on minerals and materials processing and provides some of the key industrial processes that use a Rotary Kiln as the primary workhorse. Rotary Kiln technology evolved from the struggles of early engineers and inventors to produce cement and lime in an efficient, safe, and economic way. The cement and lime processes and some of the carbothermic reduction processes that employ the Rotary Kiln as the primary device are described. The processes of iron ore reduction (the SLRN process) and illmenite ore reduction (the Becher process) and the lightweight aggregate process are examined. Rotary cement Kilns can be classified into wet-process Kilns, semi-dry Kilns, dry Kilns, preheater Kilns, and precalciner Kilns. The pertinent process chemistry and the heat requirements that drive them so as to be consistent with the transport phenomena theme are shown.
Zhijuan Hu - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of NO formation in cement Rotary Kiln
Journal of Chemical Industry and Engineering, 2020Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:Based on a set of mathematical models describing the physical and chemical processes(gas-solid flow,pulverized coal combustion,zone heat flux of clinker,and NO formation and reduction)in a cement Rotary Kiln,the distributions of gas temperature and gas components(O_2,CO,NO)were obtained by numerical simulation of a 3000 t·d~ -1 full scale cement Rotary Kiln with four-channel burner.Besides,the mechanisms of NO formation and reduction in the cement Rotary Kiln were analyzed.The results indicated that the amount of NO mainly came from thermal NO and fuel NO.Thermal NO played a dominant role in the NO amount.Fuel NO was mainly formed in the combustion zone,while thermal NO was mainly formed in the high temperature sintering zone.In addition,mutual inhibition existed in the formation process of fuel NO and thermal NO.
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modeling of pulverized coal combustion in cement Rotary Kiln
Energy & Fuels, 2006Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:In this paper, based on analysis of the chemical and physical processes of clinker formation, a heat flux function was introduced to take account of the thermal effect of clinker formation. Combining the models of gas-solid flow, heat and mass transfer, and pulverized coal combustion, a set of mathematical models for a full-scale cement Rotary Kiln were established. In terms of commercial CFD code (FLUENT), the distributions of gas velocity, gas temperature, and gas components in a cement Rotary Kiln were obtained by numerical simulation of a 3000 t/d Rotary Kiln with a four-channel burner. The predicted results indicated that the improved model accounts for the thermal enthalpy of the clinker formation process and can give more insight (such as fluid flow, temperature, etc,) from within the cement Rotary Kiln, which is a benefit to better understanding of combustion behavior and an improvement of burner and Rotary Kiln technology.
Yi Zhao - One of the best experts on this subject based on the ideXlab platform.
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Simulated Feedback Mechanism-Based Rotary Kiln Burning State Cognition Intelligence Method
IEEE Access, 2017Co-Authors: Keqiong Chen, Weitao Li, Jianping Wang, Wei Li, Yi ZhaoAbstract:Burning state directly determines the clinker quality index in the Rotary Kiln sintering process. A simulated feedback mechanism-based Rotary Kiln burning state cognition intelligence method and a calculating model are explored for the purpose of imitating the human cognition process with repeated comparison and inference. The flame image feature space is optimized progressively using the evaluation of uncertain cognition results with different values of cognition demand to realize the simulated feedback cognition mode from global to local. First, the simulated feedback mechanism-based Rotary Kiln burning state cognition intelligence method with the coupling operation of the training layer and cognition decision layer is proposed, and the framework of the model is described. Second, the evaluation index system of uncertain cognition results based on the bag of words model, latent semantic analysis method, and entropy theory is constructed. Third, the simulated feedback mechanism based on the evaluation of uncertain cognitive results is established, and a concrete calculation model is given. Fourth, the simulated feedback mechanism-based Rotary Kiln burning state cognition intelligence system is designed, and the relevant cognition intelligence algorithm is provided. Finally, a simulation experiment is carried out with the collected burning zone flame image of a Rotary Kiln. An average recognition accuracy of 92.32% is achieved with a minor standard deviation in accuracy. The experimental results show that our method is effective and outperforms other open-loop recognition methods with the global configuration feature of flame image.
Shijie Wang - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of NO formation in cement Rotary Kiln
Journal of Chemical Industry and Engineering, 2020Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:Based on a set of mathematical models describing the physical and chemical processes(gas-solid flow,pulverized coal combustion,zone heat flux of clinker,and NO formation and reduction)in a cement Rotary Kiln,the distributions of gas temperature and gas components(O_2,CO,NO)were obtained by numerical simulation of a 3000 t·d~ -1 full scale cement Rotary Kiln with four-channel burner.Besides,the mechanisms of NO formation and reduction in the cement Rotary Kiln were analyzed.The results indicated that the amount of NO mainly came from thermal NO and fuel NO.Thermal NO played a dominant role in the NO amount.Fuel NO was mainly formed in the combustion zone,while thermal NO was mainly formed in the high temperature sintering zone.In addition,mutual inhibition existed in the formation process of fuel NO and thermal NO.
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modeling of pulverized coal combustion in cement Rotary Kiln
Energy & Fuels, 2006Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:In this paper, based on analysis of the chemical and physical processes of clinker formation, a heat flux function was introduced to take account of the thermal effect of clinker formation. Combining the models of gas-solid flow, heat and mass transfer, and pulverized coal combustion, a set of mathematical models for a full-scale cement Rotary Kiln were established. In terms of commercial CFD code (FLUENT), the distributions of gas velocity, gas temperature, and gas components in a cement Rotary Kiln were obtained by numerical simulation of a 3000 t/d Rotary Kiln with a four-channel burner. The predicted results indicated that the improved model accounts for the thermal enthalpy of the clinker formation process and can give more insight (such as fluid flow, temperature, etc,) from within the cement Rotary Kiln, which is a benefit to better understanding of combustion behavior and an improvement of burner and Rotary Kiln technology.
Jie Li - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of NO formation in cement Rotary Kiln
Journal of Chemical Industry and Engineering, 2020Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:Based on a set of mathematical models describing the physical and chemical processes(gas-solid flow,pulverized coal combustion,zone heat flux of clinker,and NO formation and reduction)in a cement Rotary Kiln,the distributions of gas temperature and gas components(O_2,CO,NO)were obtained by numerical simulation of a 3000 t·d~ -1 full scale cement Rotary Kiln with four-channel burner.Besides,the mechanisms of NO formation and reduction in the cement Rotary Kiln were analyzed.The results indicated that the amount of NO mainly came from thermal NO and fuel NO.Thermal NO played a dominant role in the NO amount.Fuel NO was mainly formed in the combustion zone,while thermal NO was mainly formed in the high temperature sintering zone.In addition,mutual inhibition existed in the formation process of fuel NO and thermal NO.
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Content-Based Rotary Kiln Flame Image Retrieval
2008 Congress on Image and Signal Processing, 2008Co-Authors: Hongliang Zhang, Xiangtao Chen, Jie LiAbstract:In this paper, a content-based image retrieval system for Rotary Kiln flame image (CBIR-RKFI) is introduced for the purpose of making good use of Rotary Kiln flame images. It calculates the texture and fire & clinker features of the flame image, then, through the similarities comparison, it returns a set of original retrieval results. Moreover, with the users’ relevant feedbacks, it optimizes the final retrieval results. A prototype system was realized based on the Rotary Kiln image database that contained more than 500 Rotary Kiln flame images (Sampled in an alumina Rotary Kiln). Retrieval experiments with different features were carried out. The results demonstrate the effectiveness of the retrieval methods, and among them, the integrated features based method has the highest precision (84%). The research can provide strong support for modern Rotary Kiln supervision and management.
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modeling of pulverized coal combustion in cement Rotary Kiln
Energy & Fuels, 2006Co-Authors: Shijie Wang, Jie Li, Jidong Lu, Weijie Li, Zhijuan HuAbstract:In this paper, based on analysis of the chemical and physical processes of clinker formation, a heat flux function was introduced to take account of the thermal effect of clinker formation. Combining the models of gas-solid flow, heat and mass transfer, and pulverized coal combustion, a set of mathematical models for a full-scale cement Rotary Kiln were established. In terms of commercial CFD code (FLUENT), the distributions of gas velocity, gas temperature, and gas components in a cement Rotary Kiln were obtained by numerical simulation of a 3000 t/d Rotary Kiln with a four-channel burner. The predicted results indicated that the improved model accounts for the thermal enthalpy of the clinker formation process and can give more insight (such as fluid flow, temperature, etc,) from within the cement Rotary Kiln, which is a benefit to better understanding of combustion behavior and an improvement of burner and Rotary Kiln technology.
