Novel Sensor Platform Deployed for Detection of Nanoparticle Concentration in Production Oil and Gas Streams

S. Van Fleet
Micromem Applied Sensor Technologies, Inc., US

Keywords: nanoparticles, oil, gas

Summary:

Whenever water flooding is utilized to support pressure requirements in well production, there is always the risk that water will breakthrough and mix with the oil stream. This is obviously a negative situation and a methodology was needed to be able to better understand when water breakthrough occurs. A decision was made to inject nanoparticles into the seawater and deploy a novel sensing platform on the producing stream to detect water breakthrough instances and the concentration of the nanoparticles. This technology can provide a valuable tool to producer for managing their water flood programs. 20 nanometer magnetic nanoparticles with functionalized surfaces were designed to support up conversion fluorescence. Fluorescence up conversion particles absorbs light in the near infrared (NIR) and emits light in the visible range. The up conversion eliminates any impact on concentration measurement due to background noise from naturally occurring fluorescence in oil. The sensor platform consists of two integrated processes; 1) a magnetic collection subsystem that directs the nanoparticles to a target where they are held and integrated over time, and 2) a fluorescence resonant energy transfer subsystem that utilizes an evanescent field that is capable of propagating 200 nm or deeper into high opaque solutions. The laser initiated up conversion results in a strong process signal that is representative of the concentration of the nanoparticles in the oil process stream. By designing the functionalized surface of the nanoparticles, multiple signature nanoparticles can be injected into the wells simultaneously and subsequently can be highly differentiated by the sensor platform. The sensor platform has been validated at detecting 20 nm magnetic nanoparticles at a concentrations less than 1 part per billion. The sensor platform utilizes fiber optics and is highly ruggedized for severe environmental applications. This in-field sensor platform eliminates the long time delay associated with shuttling samples around the world and accommodates remote communications allowing continuous sampling and reporting of production streams.