Fiber-Optic Sensor with Simultaneous Temperature, Pressure, and Chemical Sensing Capabilities

A key to improving energy efficiency in the chemical and petrochemical industries is the ability to monitor in situ such parameters as temperature, pressure and chemical composition of the process stream under harsh and extreme conditions. Instruments with the required capabilities and/or robustness currently either do not exist or are inadequate. A fiber-optic sensor which combines temperature, pressure, and chemical sensing capabilities into a single strand of sapphire fiber using a novel measurement strategy will be developed. The integration of the three measurement capabilities into a single probe minimizes both the cost and intrusiveness of the device. The feasibility of all three sensor concepts for measuring temperature, pressure and chemical composition has been demonstrated. Crucial data have been obtained which allowed the capabilities of each sensor to be projected. Additionally, quantitative models for the three sensors have been developed. The temperature, pressure and chemical sensors will be optimized individually through a series of experiments designed to isolate the various effects. Then an integrated probe incorporating all three sensors will be fabricated and tested. The Phase II project will culminate in a 90 day life test of the integrated system under conditions typically found in chemical reactors. Commercial Applications and other Benefits as described by the awardee: The multifunctional fiber-optic sensor should be suitable for the on-line monitoring of process streams in the chemical and petrochemical industries. In certain situations such as microwave and plasma processing, viable alternatives are nonexistent. Parts of the sensor package should also have commercial value in the aerospace industry, in the processing of electronic materials, and in environmental monitoring.