In-Situ, Real-Time Measurement of Melt Constituents in the Aluminum, Glass, and Steel Industries

Energy Research Company (ERCo), with support from DOE’s Industrial Technologies Program, Sensors and Automation has developed a Laser Induced Breakdown Spectroscopy (LIBS) probe to measure, in real time and in-situ, the composition of an aluminum melt in a furnace at an industrial plant. The compositional data is provided to the operator continuously allowing the operator to adjust the melt composition, saving energy, increasing production, and maintaining tighter compositional tolerances than has been previously possible. The overall objectives of this project were to: -- design, develop, fabricate, test and project future costs of the LIBS probe on bench-size experiments; - test the unit in a pilot-scaled aluminum furnace under varying operating conditions of temperature and melt constituents; -- determine the instruments needed for use in industrial environment; -- compare LIBS Probe data to readings traditionally taken on the furnace; -- get full-scale data to resolve if, and how, the LIBS Probe design should be modified for operator acceptance. Extensive laboratory tests have proven the concept feasibility. Elemental concentrations below 0.1% wt. have been accurately measured. Further, the LIBS system has now been installed and is operating at a Commonwealth Aluminum plant in Ohio. The technology is crosscutting as it can be more » used in a wide variety of applications. In the Sensors and Automation Program the application was for the secondary aluminum industry. However, this project spawned a number of other applications, which are also reported here for completeness. The project was effective in that two commercial systems are now operating; one at Commonwealth Aluminum and another at a PPG fiberglass plant. Other commercial installations are being negotiated as of this writing. This project led to the following conclusions: 1. The LIBS System has been developed for industrial applications. This is the first time this has been accomplished. In addition, two commercial installations have been completed; one at Commonwealth and another at PPG. 2. The system is easy to operate and requires no operator training. Calibration is not required. It is certified as eye safe. 3. The system is crosscutting and ERCo is evaluating seven applications, as reported in this report, and other applications to be reported later. 4. A business plan is being completed for each of the near term markets. ERCo is committed to achieving continued commercial success with the LIBS System. 5. A world wide patent has been issued. 6. The energy savings is substantial. The annual energy savings, by 2010, for each industry is estimated as follows: o Secondary Aluminum – 1.44 trillion Btu’s o Glass – 17 to 45 trillion Btu’s o Steel – Up to 26 trillion Btu’s « less