This paper investigates some fundamental aspects of a "vaporiser" for recovering trapped retrograde condensate in the formation that is formed during exploitation gascondensate reservoirs in depletion regime. The thermodynamic test of seven different gas-condensate systems and analysis of the liquid and gas phase's samples which were taken under the same thermobaric conditions was provided wide information about the occurrences in the reservoir fluids. It was identified that the solubility capability of gas mixture in the hydrocarbon condensate is elevated and improved as a "vaporiser" if it's critical temperature is increased but compressibility factor and critical pressure are decreased. It was determined that, improving the solubility of gas components in the condensate decreases the system fog up and retrograde condensation pressures and improves stability of aerosol condition of gas-condensate fluid. Therefore, injected gas for gas cycling or re-vaporization of condensate from the core can be controlled for the purpose of increasing its solubility.Keywords: gas-condensate, gas injection, fog up pressure, gas solubility, gas solubility, dissolved gas vaporization of heavy hydrocarbon ends and connate water, the reduction of the condensate/gas ratio and RDP pressure, etc. 12,15 Nevertheless, successful design and implementation of enhanced condensate recovery schemes require accurate prediction of the compositional effects that control the local vaporization/displacement efficiency. In line with these conclusions, and also results which were obtained in the earlier works 4,14,15 in this paper, we intended to find out a way of improving the effectiveness of "vaporiser" for the recovering trapped retrograde condensate in the formation, which is left after primary production. To this purpose, this paper performed an experimental investigation into this phenomenon as it is problematic during mathematical modelling.
Investigation method and procedure
Laboratory apparatusesExperiments were carried out on a УГК type of PVT bomb, which is a standard apparatus for determining thermodynamic characteristics and the phase behaviour of gas condensate systems. 1 The schematic diagram of the experimental laboratory apparatus and the purposes of the laboratory modules are presented in the Figure 1. The maximum working pressure of the PVT bomb is 45MPa, maximum working temperature is 80°C and cell volume is 3x10 -3 m 3 . As shown in the diagram Figure 1, the laboratory facility can be divided into 9 Modules:
Figure 1 Schematic representation of laboratory apparatusModule 1: Module 1 is for handling natural gas from the bottle. It is equipped with Natural Gas Bottle-NGB, CO 2 Bottle-CB, Nitrogen Bottle-NB, Pressure Control Valve-PCV, Flow Meter-FM and normal Isolation Valve-IV. Sample Connection-SC allows the provision of sampling for composition analyses. This module can be linked very easily with Modules 3 and 5 by manifold (Module 9) for recombining gas mixture and gas-condensate system.
Module 2:Module 2 is for han...