Publications

Low-flowing wellhead temperature (FWHT) caused an unstable separator condition and a hydrate formation problem during deepwater gas well tests (Abadi-D and Abadi-E) conducted at Abadi gas field. Steady state and dynamic temperature modeling was conducted to understand the mechanism through which the low FWHT was measured during these well tests. It was recognized that the significant heat loss in the riser section was occurring because of natural convection in riser annulus fluid, which was low viscous potassium chloride (KCL) brine. Temperature modeling also suggested that higher FWHT could be achieved by displacing riser annulus section with higher viscous fluid to minimize heat loss by natural convection. The new well test design was generated for Abadi-F, which was drilled after Abadi-D and Abadi-E. Based on this new design, the Abadi-F well test was conducted by first displacing the entire system with KCL brine to prevent malfunction of downhole tools. As the second step, only the riser annulus section was displaced by drilling mud, prior to perforation. As a result, higher FWHT of more than 100 deg. F was achieved in Abadi-F test #2, and this high FWHT contributed to stabilizing separator condition and to avoid of any hydrate problems. This paper presents the methodology utilized to evaluate the temperature heat loss mechanism in deepwater gas well tests, and also presents techniques to optimize flowing temperature by utilizing the temperature insulation effect of riser fluid in a practical and cost-effective manner.