Development of downhole NRS in DST operation gives confidence in reservoir mercury concentrations during appraisal against measurements taken from separator lines
Expro's client was appraising a new field in the North Sea for potential development
With a history of mercury in the region, concerns were raised about the potential impact on the process facility design and export route
Due to limitations on flaring, only a short Drill Stem Test (DST) was planned, which would limit the availability of representative samples at the surface
Representative mercury measurements were a priority objective for the test, but a full program of sampling and onsite analysis was also planned
Expro Excellence
Expro provided the Non-Reactive Sampler (NRS) to be integrated within the DST string using Expro's sampling carrier
Working with the client Expro's NRS was configured to ensure perfect integration with the 3rd party DST provider for triggering the samplers
Multiple NRS samples were taken for mercury and hydrogen sulfide measurements, with analysis conducted immeditately after tools were at the surface to minimize scavenging of reactive components
Expro's multi-skilled crew were able to deliver all bottomhole sampling and chemistry requirements, negating the need for separate NRS operators and reducing POB
Value to Client
NRS measurements showed excellent agreement with each other
Mercury measurements conducted from the separator were confirmed to be lower than those obtained from the downhole NRS tools
The client had confidence in the concentrations reported from the NRS despite the short flow test
The client was able to proceed with their field development plans, factoring in the reservoir contaminant concentrations
NRS will now be included in all the client's future DSTs
Contact
For further information, please contact WFM@expro.com.