الفهرس | Only 14 pages are availabe for public view |
Abstract A typical problem associated with gas condensate wells operating below dew point is that of condensate blocking. As the pressure near the well falls below the dew point, liquid drops out and condensate starts accumulating. It reduces relative permeability to gas and hence may cause significant decline in the well productivity. The main objective of this thesis was to study the impact of hydraulic fracturing on the productivity of gas condensate wells. A single-well model was simulated using compositional simulator. The results show that a vertical fracture improves the conductivity of a gas condensate well significantly, and this increase depends on many factors. Effect of such factors such as non-Darcy flow, capillary number was simulated. It is demonstrated that non-Darcy flow can decrease the well productivity by a factor on the order of 2 to 3. In addition, a sensitivity analysis of various parameters such as fracture dimensions, fracture conductivity, reservoir permeability, drawdown, gas end-point relative permeability was done. The results showed that productivity improvement is highest for low permeability reservoirs. The well productivity is sensitive to dimensionless fracture conductivity when it lies in the range of 0.1 to 10 Furthermore, a comparative study was done on the performance of unfractured horizontal wells and fractured vertical wells. Sensitivity of parameters such as vertical permeability, reservoir permeability was studied. The results show that the productivity of the horizontal wells was greater than that for the fractured vertical wells by a factor on the order of 2, even at low values of vertical permeability. |