About: This article is published in Journal of Industrial and Engineering Chemistry.The article was published on 1914-09-01 and is currently open access. It has received 5 citation(s) till now. The article focuses on the topic(s): Rotary kiln.
Abstract: Rotary kilns are widely used in several branches of the chemical industry. In order to control the temperature of the solid and the gas flowing through the kiln, it is important to understand the heat exchange phenomena that occur. The design and construction of a novel experimental device to study heat exchange in rotary kilns is described. The device, which comprises a rotary kiln equipped with an external electrical heating system, enables the study of the influence of various parameters such as the solid flow rate, the kiln inclination angle, the rotational speed, or the presence of lifters on heat exchange and in particular on the heat exchange coefficient between the solid and the wall. Preliminary experimental results concerning the influence of the solid flow rate and the rotational speed on the solid-to-wall heat exchange coefficient are presented.
Abstract: The transverse flow of cohesive powders in rotary kilns equipped with lifters was studied experimentally and theoretically. A laboratory device was built up in which the flow of uranyl difluoride (UO2F2), uranium sesquioxide (U3O8) and uranium dioxide (UO2) powders was filmed, recorded and analyzed using partly manual image analysis techniques. Experiments were performed both at room temperature and at high temperature. A constitutive law describing the powder discharge was derived, involving a relationship between the volume fraction of powder contained in a lifter and the angular position of this lifter. This law based on geometrical calculations is successfully compared with the experimental results of unloading.
Cites background from "The Development of the Rotary Kiln ..."
...For over a century , rotary kilns have been widely used in the inorganic chemistry industry....
Abstract: The axial and transverse solid distribution of a cohesive powder in flighted rotary kilns was calculated from an original method based on the lifter discharge law previously determined, geometrical calculations and supplementary measurements (in particular the fall velocity of the powder at high temperature). At a given axial position, the quantity of powder falling through the gas, the total quantity of flighted powder as well as the quantity remaining in the bulk are thus calculated; the axial bed depth profile is obtained from the Saeman-Kramers-Afacan model.
...For over a century (Meade, 1914), rotary kilns have been widely used in the inorganic chemical industry....
Abstract: Pyrolysis is a promising process to convert municipal waste into fuels in solid, liquid or gaseous forms or value-added chemicals. The composition of pyrolysis products is affected by many factors, among which the configuration of the pyrolysis reactor is one of the essential parameters, as it influences the heat transfer, mass transfer, residence time of the reaction intermediates, interaction of the volatiles, etc. Up to now, there are varied types of pyrolysis reactors including the rotary-kiln, fixed-bed, batch and semi-batch, fluidized-bed, tubular, plasma and microwave that have been used in the pyrolysis of municipal waste. Each type of reactor has its own configuration and affects the pyrolysis process of municipal waste in distinct ways. There is a necessity for revisiting the progress of the investigation of the characteristics of the pyrolysis of municipal waste in different types of reactors, especially in terms of the kinetics of pyrolysis and the distribution of products. In addition, the techno-economic aspects of the pyrolysis of municipal waste in varied types of reactors are discussed, aiming to assess the potential for large-scale or commercial applications.
Abstract: The rotary kiln was invented in the middle of the nineteenth century as a continuous reactor to solve the problem of the tedious and high man power batch processes in the chemical industry. It was then applied at the beginning of the twentieth century in the metallurgical industry and became later an essential reactor in both industries.