Multiple Hydraulic Fractured Vertical Wells in Gas Condensate Reservoirs

Abstract

Gas reservoirs can be classified into dry gas reservoirs, wet gas reservoirs and Gas condensate reservoirs. In gas condensate reservoirs, the reservoir temperature lies between the critical temperature and the cricondentherm. The gas will drop out liquid by retrograde condensation in the reservoir, when the pressure falls below the dew point. This heavy part of the gas has found many application in industry and also in daily life and by remaining in reservoir not only this valuable liquid is lost but also its accumulation will result in forming a condensate bank near the well bore region which makes a considerable reduction in well productivity. This highlights the need to find an economical way to increase the condensate recovery from these reservoirs. Wells in gas condensate reservoirs usually exhibit complex behaviors due to condensate deposition as the bottom hole pressure drops below the dew point. Formation of this liquid saturation results in reduced gas relative permeability around the well bore and a loss of gas productivity. One of the several ways of minimizing the pressure drop in order to reduce liquid drop-out is hydraulic fracturing before or after the development of the condensate bank. The pressure transients are often used as a reliable evaluation of stimulation performance for field development planning. It has been shown that condensate deposits effects can be identified and quantified by well test analysis dealing with a well test composite behavior; which, in presence of hydraulic fractures becomes much more complex. But the various impacting factors of stimulation; such as fracture length, conductivity, orientation, etc. can also be observed and defined in these analyses. In this paper, modeling and interpretation of pressure transient responses of multiple hydraulic fractured horizontal wells using a numerical reservoir model has been investigated.