Performance analysis of a horizontal well located in an underground gas storage facility

Abstract

Nowadays, energy raw materials, especially environmentally friendly raw materials, are becoming increasingly important. These raw materials include natural gas called the "blue fuel". As it is known, natural gas is extracted from deposits located at often great depths by means of both vertical and horizontal drilling.  It is important that both vertical and horizontal wells are characterised by high efficiency in terms of obtaining the highest possible productivity, which will allow to exploit the existing resources of the deposit in the shortest possible time. 

The paper analyses the influence of such factors as reservoir pressure, thickness of reservoir, length of a horizontal section, average permeability of a reservoir, turbulence coefficient and water exponent on the process of lifting a liquid phase during operation of
a horizontal well. The calculations were carried out using data concerning exploitation of the "B" natural gas field. The calculations were carried out using the "IHS PERFORM" computer programme, which is the leading industry software for carrying out analyses of productivity changes in gas wells. The following correlations were used in the horizontal well performance analysis:

- Joshi's correlation for calculating productivity for a horizontal well

- Hagedorn & Brown correlation for determining the course of pressures in a well for two-phase flow,

- Lee, Gonzalez & Eakin correlation for calculating changes in gas viscosity, and

- Dranchuk & Purvis - Robinson correlation for calculation of deviation factor of real gas "z".

The results of the calculations are presented in the form of graphs. In the final part of the article, conclusions are given, summarising the results of the analysis. In the further part of the article the author focused on the course of operation of a horizontal well located at an underground gas storage facility.