Grantee Research Project Results
Final Report: Detecting and Quantifying the Evolution of Hazardous Air Pollutants Produced During High Temperature Manufacturing: A Focus on Batching of Nitrate Containing Glasses
EPA Grant Number: R828737C005Subproject: this is subproject number 005 , established and managed by the Center Director under grant R830420
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Center for Environmental and Energy Research (CEER)
Center Director: Earl, David A.
Title: Detecting and Quantifying the Evolution of Hazardous Air Pollutants Produced During High Temperature Manufacturing: A Focus on Batching of Nitrate Containing Glasses
Investigators: Jones, Linda E. , Clare, Alexis G.
Institution: Alfred University
EPA Project Officer: Chung, Serena
Project Period: September 1, 2001 through August 31, 2003
RFA: Targeted Research Center (2000) Recipients Lists
Research Category: Targeted Research
Objective:
Nitrogen oxides (NOx) emission from glass manufacturing presents a pollution concern. The sources of NOx emissions are thermal, prompt, fuel, and, in the case of glass, batch NOx. Batch NOx is the result of nitrate decomposition. The objective of this work was to accurately and sensitively identify and measure the concentrations of NOx, SOx, particulate, and volatile alkali emissions in the effluent gas of a glass melt.
Summary/Accomplishments (Outputs/Outcomes):
We worked on developing the analytical technology necessary to accurately and sensitively measure air toxics produced during glass batching and melting of nitrate-containing glass. We used a unique set of gas analysis tools in the form of combining Mass Spectroscopy and Fourier Transform Infrared Spectroscopy coupled to a high temperature thermogravimetry-differential scanning calorimetry (TG/DSC) system. In the development of these tools and analytical techniques, we investigated the mechanisms associated with the release of emissions during glass batching and melting of nitrate-containing glass compositions that are of critical importance for nuclear waste storage. We focused our work on the fining agent potassium nitrate.
Results
Nitrates are deliberately added in glass batch as fining agents to lower the melting points, decrease the viscosity of glass melts, and act as strong oxidizing agents. Even with all of these benefits, however, NOx emissions produced by nitrate decomposition from glass batch is an environmental problem. This study addressed the mechanism connected with the decomposition of a common fining agent, potassium nitrate.
This project addressed the complete sequential decomposition of potassium nitrate using TG/DSC experiments. The thermal calculation was performed using F*A*C*T (Facility for the Analysis of Chemical Thermodynamics) software package developed by A.D. Pelton and l’Ecole Polytechnique that employs Gibbs free energy minimization as the calculation method. The decomposition experiments were performed in a NETZSCH 409 CD TG/DSC system coupled to a Fourier Transform Infrared (FTIR) for gas identification and quantification.
Thermochemical calculations have identified the emission species and their dependence on temperature and processing atmosphere. The theoretical results agree quite well with the observations via thermochemical decomposition between room temperature and 1,300°C.
Nitrate decomposes into the nitrite and evolves oxygen, then the nitrite undergoes two possible decomposition steps with solid oxide products. Nitrate also may decompose directly into oxide, peroxide, or superoxide. These reactions may occur simultaneously, consecutively, or overlap depending on the different experimental conditions.
There is remarkable commonality between the predicted chemistry and that observed experimentally. The sequence of supported decomposition events is as follows: (1) KNO3 in Ar undergoes an ordered KNO3 (s) to disordered KNO3 (s2) transition at 131.7°C, ending at 144.2°C; (2) KNO3 in Ar melts at 330.6°C, ending at 339.7°C; and (3) at 620.2°C, the KNO3 (s) begins to decompose. Decomposition ends at 872.9°C.
FTIR spectra taken from the KNO3 decomposition in Ar at 500°C, 700°C, and 750°C respectively, show that at 500°C, no NOx evolution occurs; at 700°C, the emission includes NO ( ν2 1,876cm-1), NO 2 ( ν3 1,621cm-1), and N 2O ( ν2 1,299cm-1); and at 750°C, NO 2 has disappeared completely. This tells us that NO 2 evolved only at the onset of the decomposition between 620°C and 700°C.
Supplemental Keywords:
NOx, SOx, nitrogen oxides, alkali emissions, nitrates, nitrites, thermodynamic, thermogravimetric, glass melt effluent gas, mass spectroscopy, Fourier Transform Infrared Spectroscopy, FTIR, TG/DSC, thermogravimetry-differential scanning calorimetry, thermochemical decomposition, potassium nitrate,, Scientific Discipline, Air, air toxics, Air Pollutants, Environmental Chemistry, Environmental Monitoring, aerosol particles, gaseous effluent streams, mass spectrometry, air sampling, Sox, hazardous air pollutants (HAPs), nitrogen oxides (Nox), glass manufacturingRelevant Websites:
Progress and Final Reports:
Original AbstractMain Center Abstract and Reports:
R830420 Center for Environmental and Energy Research (CEER) Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R828737C001 Environmental Impact of Fuel Cell Power Generation Systems
R828737C002 Regional Economic and Material Flows
R828737C003 Visualizing Growth and Sustainability of Water Resources
R828737C004 Vibratory Residual Stress Relief and Modifications in Metals to Conserve Resources and Prevent Pollution
R828737C005 Detecting and Quantifying the Evolution of Hazardous Air Pollutants Produced During High Temperature Manufacturing: A Focus on Batching of Nitrate Containing Glasses
R828737C006 Sulfate and Nitrate Dynamics in the Canacadea Watershed
R828737C007 Variations in Subsurface Denitrifying and Sulfate-Reducing Microbial Populations as a Result of Acid Precipitation
R828737C008 Recycling Glass-Reinforced Thermoset Polymer Composite Materials
R828737C009 Correlating Clay Mineralogy with Performance: Reducing Manufacturing Waste Through Improved Understanding
R830420C001 Accelerated Hydrogen Diffusion Through Glass Microspheres: An Enabling Technology for a Hydrogen Economy
R830420C002 Utilization of Paper Mill Waste in Ceramic Products
R830420C003 Development of Passive Humidity-Control Materials
R830420C004 Microarray System for Contaminated Water Analysis
R830420C005 Material and Environmental Sustainability in Ceramic Processing
R830420C006 Interaction of Sealing Glasses with Metallic Interconnects in Solid Oxide and Polymer Fuel Cells
R830420C007 Preparation of Ceramic Glaze Waste for Recycling using Froth Flotation
R830420C008 Elimination of Lead from Ceramic Glazes by Refractive Index Tailoring
R830420C010 Nanostructured C6B: A Novel Boron Rich Carbon for H2 Storage
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.