How to treat well boundary conditions is a difficult issue when formulating and coding a multiphase numerical reservoir simulator. The difficulty arises because the partial differential equations governing multiphase subsurface flow are of a mixed parabolic-hyperbolic type. Maximum changes in primary variables and mass/heat fluxes occur only at boundaries or well nodes. Consequently, these well...

Oilfield Review Autumn 2011: 23, no. 3. Copyright © 2011 Schlumberger. ClearFRAC and HiWAY are marks of Schlumberger. In 1947, Stanolind Oil & Gas performed the first experimental hydraulic fracturing treatment in the Hugoton field in southwestern Kansas, USA. Since then, E&P companies have employed this reservoir stimulation technique extensively to enhance or prolong well productivity. Indeed...

Pipelines, wellbores and ground installations are permanently controlled by sensors spread across the crucial points in the whole area. One of the most popular techniques to support proper oil drive in a wellbore is a Gas Lift. In this paper we present the concept of using wireless sensor network (WSN) in the oil and gas industry installations. Assuming that Gas Lift Valves (GLVs) in a wellbore...

Geopressured reservoirs can serve as ample source of geothermal energy with temperatures as high as 140 0C. Salinities are typically high in these reservoirs due to the dissolution of surrounding salt domes. Cement retrogression can occur under these geopressured geothermal conditions resulting from calcium silicate hydrate [3CaO2SiO23H2O] phase in hydrated cement converting to alpha dicalciu...

Geopolymer cement was evaluated as wellbore sealing material for carbon dioxide geosequestration application. Curing of cement system in saline water and strength testing in triaxial stress state condition under lateral confinement is relevant to primary cementing in CO2 geosequestration wellbore in saline aquifer. Geopolymer cement was cured in saline water (both at ambient conditions for 28 d...

The change from steerable motor to rotary steerable system has been both technically and commercially successful in Lybia. Through these case histories the paper will demonstrate benefits resulting from the use of rotary steerable systems that have led to a step change in overall drilling performance in the Middle East. This paper describes the successful introduction and application of a rotar...

The deliverability of liquid-dominated geothermal reservoirs is presented in terms of reservoir performance, and wellbore performance. Water influx modeling is used to match the performance of Wairakei in New Zealand, arid Ahuachapan in El Salvador. The inflow performance is given in terms of a linear productivity index for liquid-only flow, and a solution-gas drive relationship for two-phase f...