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Oxidation catalysts, e.g., those for biomass combustion in a fluidized bed (olivine sand and catalyst ShchKZ-1), were compared. Samples consisting of straw powder, straw powder and uncalcined olivine sand, straw powder and calcined olivine sand, and straw powder and crushed catalyst ShchKZ-1 were prepared. The calcined olivine sand and catalyst ShchKZ-1 had practically the same influence on the sample mass loss and heat generation from the straw by heating.

Results of determination of effective heat capacity of untreated biomass granules are furnished. It is shown that evaporation of moisture and other volatile components present in the material affects heat absorption by the material. A mathematical model of the temperature field in reactor chambers during low-temperature biomass pyrolysis is given.

A relationship is established between statistical characteristics of the random process of press-gradient pulsation in a fluidized bed and changes in the bed’s fractional composition. This relationship can be used to monitor the process of defluidization (transition of the bed from the fluidized to the non-fluidized state) based on the results of a comparative analysis of the above-mentioned statistical characteristics. The feasibility of performing such monitoring was confirmed experimentally from the combustion of lowmelting biogranules (straw granules) in a fluidized bed. It was found that the bed remains in the fluidized state as long as the dimensionless amplitude of the pressure-gradient pulsations does not exceed 0.1. The utility of the proposed monitoring method was also substantiated by comparative studies of changes in the fractional composition of a fluidized bed and the temperature and chemical composition of the flue gases.

This article presents test results for a reactor model designed for low-temperature pyrolysis of biomass. The efficiency of the pyrolysis attains maximum values at 240–250°C and a process duration of 50 min. The test results are used in the development of an industrial reactor with a capacity of 1 ton/h with respect to initial biomass.