CLIMATE AND ENVIRONMENTAL BACKGROUNDS OF FUEL UTILIZATION, INFLUENCING UPON ALTERATION THE EUROPEAN AND UKRAINIAN TRENDS OF GAS SUPPLY P.1 PRESENT REQUIREMENTS TO SELECTION THE GAS FUELS. THERMODYNAMIC EVALUATION THE PRINCIPAL CHARACTERISTICS OF GAS FUEL
Authors: Soroka B.S. 
Published: June 2023

The work examines the starting points on the formation of fuel markets in Europe within the framework of the concept of sustainable development of the countries’ economics, taking into account the main limitations, primarily the climatic and environmental consequences of fuels combustion. This approach has led in the past years to simultaneous increase in absolute volumes’ consumption of mineral (organic, carbon-rich) fuel’s flow rate and to reduction of their shares in the overall fuel balance. The relevant changes had occurred because of simultaneous production and consumption the alternative fuels, including renewable gas and energy sources. New schemes, methods and ways of fuel supply have been analyzed, including maritime transportation of liquefied fuels (liquefied natural gas LNG, liquid hydrocarbons LPG, ammonia NH3) along with creation of a modern tanker fleet with floating and land-based regasification and gas storage (FSRU) systems; systems of interconnecting the pipelines for fuel supply, including hydrogen-enriched natural gas (HENG). According to the cultivated opinion, the global warming is considered as a consequence of the carbonization of environment due to emission of C-rich combustion products (CO2) into the atmosphere. The specified contribution of CO2 to atmospheric pollution is caused by the insufficient efficiency of fuel use, for example, in heating furnaces (up to 40 % of the total amount of fuel consumed in the industry is burned in furnaces). If the emissions value of a conventional natural gas combustion systems in furnaces meets the level of emissions up to 0.45 kg СО2/kW.h, then in the case of equipping the furnace with an efficient waste gas heat recovery system, the emissions are reducing to 0.2–0.25 kg СО2/kW.h, (Wunning J.). The determinant role of the efficiency of fuel use ηf has been correlated with the scale of atmospheric pollution with greenhouse gases (CO2) emission by means of thermodynamic analysis of energy efficiency. The efficiency of fuel utilization: by enthalpy ηH and by exergy ηeff — has been computed for the cases of burning the widespread fuels and the comparative analysis has been performed. The calculations of thermal energy characteristics of the fuels have been carried out by using the original author’s methodology based upon assumption of equilibrium thermodynamics for the cases of using  the widespread gas fuels within the temperature range T from the standard T0 to the theoretical combustion temperature TT. In accordance with original author’s method the most important heat engineering characteristics of the fuels have been studied by means of approaches of equilibrium thermodynamics. Higher and lower combustion heat, higher and lower Wobbe numbers, theoretical (adiabatic) combustion temperature of the widespread fuels have been determined. An influence of hydrogen content in CH4/H2 gas fuel mixtures on the mentioned properties has been determined. From the list of firing engineering characteristics, the formation of the methane number MN for different organic and alternative fuels have been considered. The accumulated numerical values of MN for the widespread types of fuels have been stated and compared. Bibl. 38, Fig. 4, Tab. 1.