The technology of a pulsed detonation gun for gasification of organic waste with ultra-superheated steam has been experimentally demonstrated for the first time. Experiments were performed on natural gas conversion as well as on the gasification of liquid (waste machine oil) and solid (wood sawdust) waste by hot detonation products of natural gas–oxygen mixture at a frequency of detonation pulses f = 1 Hz. Periodic release of detonation products to a 100 L flow reactor provided a time-averaged mean temperature and pressure in the reactor at about 1200 K and 0.1 MPa. It is shown that the technology of a pulsed detonation gun can provide complete (100%) natural gas conversion to syngas containing H2 and CO with a H2/CO ratio of 1.25. During the gasification of liquid and solid wastes, the total volume fraction of combustible gases (H2, CO, and CH4) in the product syngas was 80 and 65% with H2/CO ratios of 0.8 and 0.5, respectively. Comparison of the experiments on natural gas conversion and liquid/solid organic waste gasification under the same conditions at f = 1 Hz showed that the composition of the product syngas in terms of H2 and CO content almost did not depend on the type of used feedstock. The estimated ideal energy gain defined as the ratio of the total energy of product syngas to the energy spent in its production from dry wood sawdust is about 4.6, i.e., the pulsed detonation technology of biomass gasification is economically very attractive.

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In the period from 2019 to 2022, the joint American–Russian space experiment (SE) Flame Design (Adamant) was carried out on the International Space Station (ISS). The purpose of the joint SE was to study the mechanisms of control of soot formation in a spherical diffusion flame (SDF) formed around a porous sphere (PS), and the radiative extinction of the SDF under microgravity conditions. The objects of this study were “normal” and “inverse” SDFs of gaseous ethylene in an oxygen atmosphere with nitrogen addition at room temperature and pressures ranging from 0.5 to 2 atm. A normal flame is a flame formed in an oxidizing atmosphere when fuel is supplied through the PS. An inverse flame is a flame formed in a fuel atmosphere when an oxidizer is introduced through the PS. This article presents the results of calculations of soot formation in normal and inverse SDFs. The calculations are based on a one-dimensional non-stationary model of diffusion combustion of gases with detailed kinetics of ethylene oxidation, supplemented by a macrokinetic mechanism of soot formation. The results indicate that soot formation in normal and inverse SDFs is concentrated in the region where the local C/O atomic ratio and local temperature satisfy the conditions 0.32 < C/O < 0.44 and T > 1300–1500 K.

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