The results of numerical experiments concerning the process of calcination of small grained limestone particles in contact with the gas phase of a fluidized bed of inert grainy material for obtaining a high-performance sorbent are given. The character of the change of the basic qualitative parameters of the obtained sorbent – droopiness, surface area, mass is presented depending on the time of residence of the initial limestones with a diameter of 80–200 nm with initial porosity e0 = 0,03–0,1 and pore diameter dpor = 3,84–17 nm in the high-reaction zone when the temperature of the gas phase of the fluidized bed is changed within 900–1200 °С. The obtained results allow further in the design stage to determine the optimum hardware and process design of the process of calcination, depending on the initial parameters of the limestone, which will provide the desired quality of the limestone sorbent in accordance with the given power installation. Bibl. 1, Fig. 10.

A detailed mathematical description of the endothermic process calcination of limestone particles is presented while they are passing high temperature zone of fluidized bed inert particles. When constructing a mathematical model of thermochemical conversion of limestone particles, are made the following key assumptions: large-grained inert particles are in the mode ideal mixing, they are acting as a thermostat, and limestone particles are removed from the fluidization bed with the heating gas in the mode piston flow; calcium oxide particles formed as a result of thermochemical processing, retain the original amount of limestone particles with a corresponding change in the current volumetric particle porosity; pressure and density of the carbon dioxide produced in the calcination process on the surface of unreacted CaCO3 and which are determining the reaction rate of calcination are equal to the value of these parameters in the radial pores of particles; particle heating is provided only due to the thermal conductivity of the solid phase and by intensity of heat exchange «limestone particles — inert particles of fluidized bed». Bibl. 7.

In dry desulfurization, for example, of gaseous combustion products of thermal power plants and incineration plants, calcium oxide CaO, as a product of firing of natural carbonate rocks, mainly limestones (CaCO3), is widely used. Firing technology, depending on the limestone heat treatment regimes, form a product with certain physicochemical properties: porosity, specific surface, shrinkage value, chemical activity. The influence of heat treatment conditions on the properties of the product obtained is studied. The possibility of fast low temperature heat treatment of finely dispersed limestone in a fluidized bed of an inert material to produce CaO of the required quality is shown. Research facility, technique for carrying out experiments and processing experimental data are described. As a result of the research, the degree of calcination of 80 % of fine limestone in a device with fluidized bed of inert material was achieved and the residence time of the particles in the inert layer was determined. Bibl. 10, Fig. 2, Tab. 1.

Досліджено можливість отримувати порожньотілі мікрокульки з перліту різних родовищ світу. Досліджен ня проводились на зразках матеріалу п’яти родовищ. Визначено залежності характеристик порожньотілих мі крокульок від режимів їх термічної обробки у псевдозрідженому шарі, залежності коефіцієнту спучування від температури, фракційного складу матеріалу та кількості зв’язаної вологи у матеріалі. Наведено опис стендів для проведення досліджень, методики проведення експерименту, мікрофотографій отриманих мікрокульок. Пока зано, що попередня термообробка з метою регулювання зв’язаної залишкової вологи у матеріалі більш суттєво впливає на характеристики готового матеріалу, ніж температура спучування. Найбільший коефіцієнт спучування К = 18 досягнуто при спучуванні зразків матеріалу турецького родовища після попередньої його термообробки з метою зменшення зв’язаної вологи з 3,8 до 3,1 %.

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