Patent ID: 8290632

Claim:
A method for controlling influx of crude oil, natural gas and/or other effluents into inflow zones of a well comprising a plurality of distinct inflow zones through which crude oil and/or natural gas and/or other effluents are produced, which zones are each provided with an inflow control device (ICD) for controlling the fluid influx through the zone into the well, the method comprising: a) assessing the flux of crude oil, natural gas, water and/or other effluents from the well; b) monitoring production variables, including the position of each ICD and/or the fluid pressure in each inflow zone upstream of each ICD and/or the fluid pressure in a well tubular downstream and in the vicinity of each ICD and optionally further including the fluid pressure and/or other characteristics of the effluent flowing through the well or surface tubulars connected to a wellhead of the well and/or the position of one or more valves arranged in the well and/or at or near the wellhead, such as the position of a the production choke valve (FCV) at or near the wellhead; characterized in that the method further comprises: c) performing a well test during which production from the well is varied by sequentially adjusting the position of each of the ICDs and the flux of crude oil, natural gas and/or other well effluents is assessed in accordance with step a; d) monitoring during step c production variables in accordance with step b; e) deriving from steps c and d a zonal production estimation model for each inflow zone of the well; and f) adjusting each ICD to control the influx of crude oil, natural gas and/or other effluents into each inflow zone on the basis of data derived from the zonal production estimation model for each inflow zone of the well; g) repeating steps c), d), e) and f); h) deriving from steps c) and d) a well and zonal production and pressure prediction model relating the ICD settings to the pressures and efflux for each inflow zone of the well; i) defining an operational optimisation target for the zones and the overall well, consisting of a target to be optimised and various constraints on the zonal and well flows or pressures or other production variables monitored in accordance with step b or otherwise estimated; j) computing from the models of step h) adjustments to settings of the production choke valve (FCV) and zonal ICDs such that the optimisation target of step i) is approached; k) adjusting the settings of the production choke valve and the zonal ICDs on the basis of the computations made in accordance with step j); and l) repeating steps h), i), j) and k) from time to time.