Keyword: «natural gas production»

The inverse problem of determining the gas mass flow by measurements of wellhead pressure with a cross-section of the well varying in length and time is solved by mathematical modeling methods, which makes it possible to identify signs of hydrate formation in it, consisting in different dynamics of pressure and temperature distribution. The results of a computational experiment were compared for two wells of the Otradninsky gas condensate field, the exploitation of which indicates that the most likely cause of complications is the gas hydrates formation both in the bottom-hole zone and in the borehole and their plumes. The influence of geocryological conditions and pressure drop in wells on the dynamics of hydrate plug formation and on the total amount of produced gas is shown.

An algorithm is proposed for determining the dynamics of changes in the mass flow rate of natural gas in a well by measuring the pressure at the wellhead, based on the method of half division (bisection, dichotomy), which has unconditional convergence. In the course of solving the problem during the gas hydrates formation and deposition, the dynamics of changes in gas pressure and temperature, as well as the flow section along the length of the well, are also calculated. Comparison of the calculation results showed that at a constant bottom-hole pressure, the implementation of this algorithm, in contrast to the previously proposed algorithm for the inverse problem, leads to an increase in the duration of the process of complete blockage of the well with hydrates and, accordingly, to an increase of the produced gas total amount.