skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Raman gas analysis for chemical looping

 [1];  [1];  [2];  [3]
  1. U.S. Department of Energy/NETL
  2. U,S Department of Energy/NETL
  3. U,S. Department of Energy/NETL
Publication Date:
Research Org.:
National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States). In-house Research; National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States)
Sponsoring Org.:
USDOE Office of Fossil Energy (FE)
OSTI Identifier:
Report Number(s):
Resource Type:
Resource Relation:
Conference: 2015 AIChE Annual Meeting, Salt Lake City, UT, November 8-13, 2016
Country of Publication:
United States
20 FOSSIL-FUELED POWER PLANTS; 47 OTHER INSTRUMENTATION; Raman gas analyzer, spectroscopy, chemical looping, gas species

Citation Formats

Buric, Michael P., Woodruff, Steven D., Weber, Justin M., and Straub, Douglas. Raman gas analysis for chemical looping. United States: N. p., 2015. Web.
Buric, Michael P., Woodruff, Steven D., Weber, Justin M., & Straub, Douglas. Raman gas analysis for chemical looping. United States.
Buric, Michael P., Woodruff, Steven D., Weber, Justin M., and Straub, Douglas. 2015. "Raman gas analysis for chemical looping". United States. doi:.
title = {Raman gas analysis for chemical looping},
author = {Buric, Michael P. and Woodruff, Steven D. and Weber, Justin M. and Straub, Douglas},
abstractNote = {},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month = 1

Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • In thermal power plants, a large amount of the useful energy in the fuel is destroyed during the combustion process. This paper presents theoretical thermodynamic studies of a new system to increase the energy conversion efficiency of chemical energy in fuels into work. The system includes a gas turbine system with chemical-looping combustion where a metal oxide is used as an oxygen carrier. Instead of conventional combustion, the oxidation of the fuel is carried out in a two-step reaction. The first reaction step is an exothermic oxidation of a metal with air and the second reaction step an endothermic oxidationmore » of the fuel with the metal oxide from the first step. The low grade heat in the exhaust gas is used to drive the endothermic reaction. This two-step reaction has proven to be one way to increase the energy utilization compared to conventional combustion. Results for a gas turbine reheat cycle with methane as a fuel and NiO as an oxygen carrier show that the gain in net power efficiency for the chemical-looping combustion system is as high as 5 percentage points compared to a similar conventional gas turbine system. An exergy analysis of the reactions shows that less irreversibilities are generated with chemical looping combustion than with conventional combustion. Another advantage with chemical-looping combustion is that the greenhouse gas CO{sub 2} is separated from the other exhaust gases without decreasing the overall-system thermal efficiency. This is an important feature since future regulations of CO{sub 2} emission are likely to be strict. Today, most of the suggested CO{sub 2} separation methods are considered to reduce the thermal efficiency at least 5--10 percentage points and to require expensive equipment.« less
  • An instrument for measuring the composition of chemical process streams at multiple points has been designed. It determines composition by a chemometric analysis of the spontaneous Raman spectrum. A Nd:YAG laser is used to excite the sample and an interferometer is used to detect the spectrum of the Raman-scattered light. The light from the laser is multiplexed to the measurement points through fiber optics. This allows the sharing of the expensive components of the system among several measurements. The instrument will be applied to distillation columns. The response time is approximately three minutes per measurement. The composition measurement range ismore » from approximately 5% to 100% with an average error of less than 2% RMS. 8 refs., 6 figs., 4 tabs.« less
  • It is well known that Raman scattering efficiency is enhanced by resonance absorption. This enhancement effect varies with the absorption strength and the characteristics of the excited states. Therefore, information on the spectral dependence of the resonance enhanced Raman effect is important and vital in the development of analytical techniques for trace constituents in aerosol particles or solution droplets. Unfortunately, ambient aerosols in general have absorption bands only in the ultraviolet spectral region, and present a very formidable task for composition analysis. The present work investigates the extent of ultraviolet Raman enhancement under the pre-resonance, resonance and post-resonance conditions, usingmore » aqueous solution droplets containing inorganic and organic matters as model aerosols. The solution droplets used in this study were generated at 50 kHz by a vibrating orifice. The nominal particle size was 45 {mu}m in diameter. The excitation laser source is the H{sub 2} Raman-shifted outputs from either the fourth harmonic of a pulsed YAG laser or the YAG pumped dye laser. The combination gives a nearly continuous tunable excitation source between 2000 and 4500{Angstrom} for the laser Raman scattering experiment. Within the coverage of the laser wavelengths, effects of pre-resonance, resonance and post-resonance Raman scattering on chromates and dichromates were studied in detail. Some preliminary results on the UV enhanced Raman scattering for the organic aerosols such as naphthalene and anthracene will be given as well.« less
  • Recent advances in fiber optics, diode lasers, CCD detectors, dielectric and holographic optical filters, grating spectrometers, and chemometric data analysis have greatly simplified Raman spectroscopy. In order to make a rugged fiber optic Raman probe for solids/slurries like these at Savannah River, we have designed a probe that eliminates as many optical elements and surfaces as possible. The diffuse reflectance probe tip is modified for Raman scattering by installing thin dielectric in-line filters. Effects of each filter are shown for the NaNO{sub 3} Raman spectrum. By using a diode laser excitation at 780 nm, fluorescence is greatly reduced, and excellentmore » spectra may be obtained from organic solids. At SRS, fiber optic Raman probes are being developed for in situ chemical mapping of radioactive waste storage tanks. Radiation darkening of silica fiber optics is negligible beyond 700 nm. Corrosion resistance is being evaluated. Analysis of process gas (off-gas from SRS processes) is investigated in some detail: hydrogen in nitrogen with NO{sub 2} interference. Other applications and the advantages of the method are pointed out briefly.« less
  • Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of Energy has funded research at the Measurement and Control Center to establish the utility of this method for on-line composition analysis in distillation columns. Laboratory evaluation and instrument employs an air-cooled laser and a thermoelectrically cooledmore » detector. The device is mounted on a three by foot cart for convenient location in control rooms. Current fiber optic extension cables allow for analysis in a cell thirty five meters from the instrument. Application of the device to acid an recovery column at Tennessee Eastman Corporation in Kingsport, Tennessee will be discussed. Sensor placement is critical to optimal application of any on-line device. Potential energy savings and product throughput increase will be detailed. 2 refs.« less