The multiple zone water injection project (MZWIP) was initiated to deliver the following key objectives: deliver zonal injection with conformance control and reliable sand management across the major layered sands of the Balakhany unconsolidated reservoirs in the BP operated Azeri-Chirag-Gunashli (ACG) fields in Azerbaijan sector of the Caspian Sea. Three years after MZWIP implementation, six wells with a total of 14 zones are injecting at required rates with zonal rate live-reporting. To achieve this multizone injection facility, the requirement for a standard ACG sand-control injector design was discounted and a non-standard sand management control technique developed using a cased & perforated (C&P) and downhole flow-control system (DHFC). During this program, BP ACG has successfully installed the world's first 10kpsi three-zone inline variable-choke DHFC wells with distributed temperature sensors (DTS) across all target injection zones. The choking DHFC provides flexibility in operations and delivers the right rates to the right zones. The DTS provides conformance surveillance, fracture assessment, caprock integrity and sand ingress monitoring capability. A customized topside logic control system provides an automatic shutin of interval control valves (ICVs) during planned or unplanned shutins to stop crossflow and sand ingress and is the primary method of effectively managing sanded annuli. The development of this MZWI solution has significantly changed the Balakhany development plan and has been quickly expanded across five ACG platforms. Accessing 2nd and 3rd zones in the same wellbore, this C&P DHFC well design is accelerating major oil volumes and will significantly reduce future development costs, maximizing wellbore utility in a slot-constrained platform.

A produced water re-injection (PWRI) well, PWRI-3, was drilled and completed from the Eastern Trough Area Project (ETAP) North Sea platform in 2008. Two previous wells, PWRI-1 and PWRI-2, were drilled early in field development to inject all produced water into a Palaeocene sandstone aquifer at 2800mTVDss, 125degC and 4100-4500psig reservoir pressure.As the fields have matured, increasing volumes of produced water need to be injected as expected. At the same time, declining injection rates into the two disposal wells has resulted in the fields becoming limited on water disposal. Oil production constraints due to produced water disposal have developed since about 2005. As a result, planning for a third PWRI well was kicked-off in 2006.This paper details the design, installation and initial performance of PWRI-3, focussing on the well completion. As a single infill well requiring mobilisation of a heavy-duty jack-up, the requirement for PWRI-3 was to deliver a high quality, high integrity, high rate, long life water injector. The multiple sources of produced water from the ETAP fields create a complex chemical cocktail, requiring the completion to cope with varying levels of CO2, H2S, chloride, sulphate, barium and production chemicals. A cemented 7" 13%Cr liner, fibreglass-lined 7" injection tubing, alloy 718 completion jewellery and a fully clad 7" tree were selected. Specific measures were taken to minimise risk of wireline damage when running perforating guns through the injection tubing. Concerns about managing increasing pressures in the Palaeocene led to the installation of a downhole gauge, to help maintain high injection rates within the limits of caprock fracturing pressures.To understand injection fracturing and to maximise injectivity, a specific sequence of perforating and bullheading was used. To reduce the environmental footprint of the rig activity, over 2500bbl of contaminated seawater (containing residual oil based mud from the mud-to-brine wellbore displacement) was bullheaded into PWRI-3 during this rig injection testing.