Wireless Online pH Measurement of Produced Fluids

QUICK FACTS
Where: North Sea
When: 2015
Duration: 10 days
Crew: 4 Engineers
What:
pH Measurement
Equipment:
2 x pH Skids + 2 x LMS Skids

Challenge

A major operator in the North Sea was planning acid stimulation of an oil producing well. In fear of causing irreparable damage to the rigs process plant which was not designed for pH levels below 3, the client asked ScanWell to supply a solution for real time monitoring of pH in produced fluids during initial flowback from the well in case any unspent acid returned from the reservoir. The planned acid stimulation could not be performed unless the clients project group found a suitable method for measuring pH in produced fluids.

Solution

ScanWell designed two portable sampling stations for continuous analysis of pH in the oil/water phase of returned fluids. One system sampled fluids as it exited the well, whilst the second system sampled fluids prior to entering the process system. A 15-minute buffer volume was installed between these two points to allow for ample reaction time and introduction of pH neutralizing agent in case pH dropped below 3.5. pH measurements were sent wirelessly to rig control room via ScanWell's SCADA system.

Result

ScanWell successfully monitored pH in the oil/water phase for the duration of the flow back. Average pH was 6.3 and never dipped below 5.5. Manual sampling performed during the operation confirmed ScanWell’s measurements.

Client Value

Due to ScanWell’s rapid development of its online pH measurement system, the client was able to perform the acids stimulation which resulted in increased oil production.