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The electrical conductivity distribution over the height of the fluidized bed (coke, fraction 0.25-0.4 mm) has been investigated experimentally under various liquefaction conditions. Analysis of the conductivity fluctuations in the fluidized bed has been performed and its mechanism, taking into account the interaction between the bed phases, is proposed.Introduction. Synthesis of materials in fluidized bed reactors is a promising and developing technology, the field of whose application is very wide. Important advantages of this technology over the other methods of material synthesis are a high intensity of internal and external heat and mass transfer in the fluidized bed, homogeneity of the bed, and the technologically important possibility of continuous operation [1][2][3][4].Many reactions of material synthesis in the fluidized bed proceed at high temperatures. Therefore, to realize such reactions, a heating source is needed. In an electrothermal fluidized bed (ETFB) consisting of conducting particles, such a source is realized as a result of the Joule heat release due to the current flow between the electrodes immersed in the bed. In so doing, a high energy efficiency of the synthesis process is provided.The first works on the use of the ETFB date back to the 1960s [3,4]. In the first decades of ETFB investigations, a large number of publications were devoted to the above problem. However, beginning from 1980s, the number of such publications decreased sharply. Under the conditions of present-day requirements on energy efficiency of technological processes and the need for new materials, interest in the ETFB is renewed.An important parameter of ETFB reactors is conduction in the fluidized bed. For the reactor to attain the required electric power, it is necessary to be able to calculate and control the electrical properties of the fluidized bed at various temperatures, blasting rates, and sizes of its particles. At present, however, there are no reliable methods for calculating the electrical characteristics of the above disperse system.In investigations of electrical properties of the fluidized bed by different authors, primary consideration was given to the dependence of the integral resistance between electrodes immersed in the bed (most often consisting of coke or graphite particles of certain fractions) on the bed blasting rate [2,[5][6][7]. However, the data available in the scientific literature are widely discrepant. For instance, according to the data of [8], the bed resistance as a function of the blasting rate passes through the maximum before U mf is reached. At the same time, in [3] it was shown that the resistance of the fluidized bed increases monotonically with increasing gas flow rate, and in [9] the resistance upon reaching U mf practically no longer depended on the flow rate.It should also be noted that attempts to investigate the local conductivity of the fluidized bed had a limited character. For example, Graham and Harvey in their work [8] investigated the dependence of resistance betwe...

The paper is devoted to the specifics in the chemical composition of synorogenic clay rocks in var ious environments: the Ural foredeep, Olyutorskii terrane, Dnestr pericratonic trough, Indus-Gang trough, etc. The compositions of the rocks are plotted in conventionally utilized discriminant paleotectonic dia grams. It is demonstrated that the bulk composition of such rocks, which were formed under active tectonic conditions typical of the collisional evolutionary phase of mobile belts, reflects the nature of the rock assem blages produced during both the divergent and the convergent (including collisional) phases. Their mean composition is the closest to PAAS as an integrated parameter of the average composition of the continental crust. The materials presented in the publication suggest that data on the bulk composition of clay rocks shown in conventionally utilized discriminant diagrams, such as SiO 2 -K 2 O/Na 2 O, K 2 O/Na 2 O-SiO 2 /Al 2 O 3 , are insufficient to reproduce the tectonic environments in which these rocks were formed.

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