Выпуск: 2 , Том: 96 , Год издания: 2023

Geochemical survey based on registration of hydrocarbons that migrate from a deposit to the Earths surface is a promising method of searching for hydrocarbon deposits. Passive concentrators containing a sorbent are used for this purpose. Passive concentrators are glass or metal tubes packed with a sorbent. The sorbents are materials that have sufficient sorption capacity for the gases under consideration and are capable of reversible desorption. After the sorbent exposure in sampling sites (pits), the samples are analyzed with a gas chromatograph. The topical problem is determination of the time required for complete desorption of the gases (saturated С1С5 hydrocarbons) from the sorbent at the preset temperature. A mathematical model of the thermal desorption of hydrocarbons from a coal fiber sorbent is suggested. The mass exchange processes are described using the linear driving force (LDF) model taking into account significant dependence of the desorption coefficient on the temperature and sorbent porosity. The model novelty consists in taking into account the structure of the coal sorbent fibers. The temperature dependences of the desorption coefficient and of the gas diffusion coefficient in the sorbent are described by the Arrhenius law. Analytical dependences were obtained for estimating the desorption time as a function of the physicochemical characteristics of the hydrocarbons and temperature. Model calculations based on the published data were performed for the methane desorption from the coal sorbent. The model parameters requiring experimental determination, primarily the activation energy of the gas desorption, were revealed. The results of the study can be used in the field of coal mining for improving the methods of searching for hydrocarbon deposits.