A spreadsheet program to optimize kinetic parameters of organic matter from laboratory pyrolysis data

Carbon Isotope Kinetics Effect on the Natural Gas Accumulation: A Case Study of the Baimiao Area, Dongpu Depression, North China

“…The cumulative value of carbon isotopes at time t , δ 13 C cum ( t ), is the ratio of methane precursor conversion. There are the following formulas: The instantaneous value of the carbon isotope δ 13 C inst ( t ) is the ratio of the reaction rate at time t . Here The formula of the carbon isotope accumulated from time t – 1 to time t δ 13 C step ( t ) is as follows: where R std is the PDB standard ratio, δ 13 C 0 is the initial carbon isotope value, R o is the initial carbon isotope ratio of the methane precursor, F *­( t ) and F ( t ) are the conversion rates of heavy carbon methane and light carbon methane at time t , respectively, r *­( t ) and r ( t ) are the reaction rates of heavy carbon methane and light carbon methane at time t , respectively, and F *­( t – 1) and F ( t – 1) are the conversion rates of heavy carbon methane and light carbon methane at time t – 1, respectively.…”

“…Carbon isotope kinetics based on hydrocarbon generation kinetics can solve the scientific problems of carbon isotope evolution and fractionation regularity under certain geological conditions. − Moreover, the kinetic process of natural gas generation and migration is objectively evaluated; the natural accumulation process is clarified; and the favorable blocks for gas accumulation are pointed out. Therefore, the study of the carbon isotope kinetics is of great significance for solving the problem of natural gas accumulation. − In recent years, the carbon isotope kinetics of natural gas has become an important research focus in the field of petroleum geochemistry − and has important application potential for explaining the process of natural gas accumulation. − …”

“…The Crammer model includes three types of models, where models I and II fit the experimental data through activation energy differences and model III simulates the processes of hydrocarbon generation and evolution of heavy carbon methane and light carbon methane, and then it obtains their respective kinetic parameters according to the corresponding calculation formula. ,, The Easy Delta model gives the calculation method of instantaneous isotope values, cumulative isotope values, and periodic cumulative isotopes . With the establishment and improvement of the above kinetic models, carbon isotope kinetics research has accomplished many achievements and have been applied in many petroliferous basins. − ,, Most scholars simulate the natural gas accumulation process mainly using carbon isotope kinetics software with the Tang model as the principal model or use the GOR-Isotope Kinetics software with the Crammer model as the principal model. Its application mainly focuses on the analysis of the evolution law of δ 13 C 1 of natural gas, gas source conditions, maturity determination, and natural gas migration, and it also focuses on establishing accumulation research and mode of accumulation. , In addition, many scholars have performed exploratory work and achieved corresponding results, − ,, such as the coal-to-methane carbon isotope kinetic fractionation model and the chemical kinetic model of carbon isotope fractionation during gas production of organic matter …”

A step-by-step model for pyrolysis kinetics of polyethylene in an autoclave under non-linear increase of temperature

“…A Lotus 1-2-3 program was proposed for pyrolysis kinetics of sedimentary organic matter [13] by assuming the total reaction consisting of parallel degradation of several hypothetical components following the Arrhenius equation and first-order kinetics, each with a different E but the same A value. Later, the model was modified for different oil shale samples [14] where on the basis of TGA data, 11 values of E j were given in advance, and 11 values of A j and of total fractional conversions, x j , were unknown parameters.…”