For any production optimisation system to function effectively it must reliably receive quality data on demand. Over the past decade the reservoir monitoring industry has been addressing the issue of reliability including implimentation of a step-change technology – Passive Optical Sensing Systems.
Since the first installation of an in-well optical pressure gauge over 10 years ago, the industry has built a substantial track record with over 85 installations of P&T gauges and hundreds of DTS installations – acceptance is growing!
Initially Optical Sensing systems were expensive, complicated to install, and could only support limited applications. Today, they are on a par with electronic gauges with respect to performance, cost and installation simplicity. The state- of-the-art in optical sensing technology includes Bragg-grating based Pressure and Temperature sensors, permanent Distributed Temperature Sensing (DTS), Single-and Multiphase Flowmeters, and Seismic sensors.
This paper describes the operation of each of the sensing systems mentioned above, the data/information provided, together with details of application case histories. These range from simple single-gauge installations to complex wells with integrated pressure sensing, flow measurements and remotely activated zonal flow control – true Smart or Intelligent Wells.
The future direction includes even more complex intelligent completions and subsea deployments. Also high accuracy distributed array temperature sensing, optical distributed pressure sensing, sand detection, and distributed strain (e.g. for riser monitoring), are just a few of the new generation of sensing systems that are described in the paper.
As subsea continues to play an important role in our industry, the presentation (not included in this paper) will also include a synopsis from the SPE ATW "In-well Optical Sensing – Subsea Well Applications – Are We Ready?" held February 7th and 8th, 2006 in Galveston.