Wax deposition in horizontal wells

In this research, wax deposition in horizontal well bores was studied. In a horizontal well, the main mechanism for wax appearance is the pressure cha nge rather than the temperature change. Six different thermodynamic models were improved for horizontal wells by adding a pressure function, and a com puter program was developed to simulate the precipitation phenomena in hori zontal wells. Solid-liquid equilibrium constants for each pseudo-component were calculated. Critical pressures and overall solid mole factions of the crude oil at different error ranges are determined. In addition to these, t he changes in productivity index due to wax deposition for steady stare and pseudo-steady state conditions were examined by the addition of a "wax fac tor". It was observed that pressure change was slightly effective on wax ap pearance in horizontal wells.