How liquid in a product of a horizontal gas well affects technological parameters of its operation
The main advantage of horizontal wells application at development of gas and gas-condensate fields is their high productivity together with reduction of risks of underlying waters breakthrough and rocks disintegration in a bottom-hole area. Operation modes for horizontal wells are calculated using hydrodynamic ratios for one- phase flows, but the presence of liquid in well products can seriously distort real parameters of the operation modes as compared with the dry wells.The article studies the effect which a liquid phase of a product imposes upon the operational characteristics of wells with subhorizontal endings. A procedure for calculating extreme and running conditions of horizontal wells operation is suggested. It takes into consideration presence of liquid in well product. Also a new approach to optimization of bottomhole structure for horizontal wells is worked out. It is shown that liquid influences the modes of well operation at all stages of field development, but at the stage of declining production such influence becomes governing. The presented calculations are based on the results of the experimental testing of gas-liquid flows carried out in the Gazprom VNIIGAZ LCC using a special test stand.