Research of the Impact of the Method of Heating of Heat Units on the Qualitative Characteristics of Treated Materials

An analytical method for calculating the chemical potentials of the components of the gas-solid system based on thermodynamic calculations of carbon potentials of the С–О–Н–N gas mixture (combustion products of the methane-air mixture) and the solid phase (alloyed steel) is developed. Dependences describing the influence of the main parameters of heating the medium composition, flow rate, as well as their interaction, on metal losses associated with decarburization are obtained.Thermodynamic calculations of carbon potentials of alloyed steel and natural gas combustion products of different composition (α=0.2÷1.2), metal and combustion products temperatures of 1,100÷1,500 K are performed.Based on the analysis of the structure of the thermal and diffusion boundary layers, it is proved that the decrease in the temperature of the layer of combustion product flowing around the solid product and surface flow rate reduces the diffusion flow of carbon in the boundary layer. This effect reduces the decarburization of steel.It is found that when heating the heat unit according to the principle of indirect radiant heating (IRH) during the operation of the flat-flame burner, the main gas volume, localized at the metal surface, has a temperature significantly lower than the layer adjacent to the lining. This reduces the metal loss with decarburization compared with furnaces of the traditional heating system.Combustion of gas in flat-flame burners with an intense circulation of combustion products in the working space of the heat unit ensures that the heated products have a uniform composition of combustion products corresponding to a practically equilibrium one. This allows recommending flat-flame burners for widespread use in modern heat-power units in the industr

Research and Control of the Purity of Production Hydrogen with a High Degree of Purification When Applying the Electrolysis Method of Production

We conducted experimental studies aimed at determining the purity of hydrogen obtained at the electrolysis installation made by Hydrogen Technologies (Norway) at the pipe plant Centravis Production Ukraine in the city of Nikopol, Ukraine.It was established that the determination of hydrogen purity and the degree of its purification from impurities (nitrogen) in microconcentrations involves two stages of measurements:− research into the presence of nitrogen in the samples of production hydrogen in the microconcentrations of [[N2] 0.001−0.01 % (rough estimate);− research into the presence of nitrogen in the samples of production hydrogen in the microconcentrations of [[N2] 0.001−0.01 % (fine assessment).We determined that the purity of production hydrogen, obtained during research, was 99.9±0.1 %. A given value for purity does not match certification indicators for purity of production hydrogen claimed by the manufacturer to equal 99.9999 %.We analyzed the reasons for the mismatch between the purity of obtained hydrogen and claimed characteristics. A detailed analysis revealed that the possible cause of high nitrogen concentration in hydrogen is the worn piston rings in the stage of compressor pistons, which causes the penetration of nitrogen in microconcentrations into production hydrogen. Piston rings in the compressor's stage were replaced. Repeated studies into purity of production hydrogen indicate that the purity of production hydrogen amounted to 99.99±0.01 %, which corresponds to the hydrogen of grade A