Testing of a Continuous Sampling Mercury CEM at the EPA-Rotary Kiln Incinerator Simulator Facility
Bibliographic record
Abstract
This report has been prepared to document the performance of the continuous sampling mercury monitoring system developed by Ames Laboratory for use as a continuous emission monitor (CEM). This work was funded by the U.S. Department of Energy, Office of Environmental Management, Office of Science and Technology, through the Mixed Waste Focus Area. The purpose of the project is to develop instrumentation and methods for spectroscopic field-monitoring applications. During FY01 this included continued development and testing of an echelle spectrometer system for the detection of mercury (Hg) by atomic absorption. Due to the relatively poor limits of detection for Hg by optical emission techniques, the CEM has been designed for the detection of elemental Hg by optical absorption. The sampling system allows continuous introduction of stack gas into the CEM for analysis of elemental and total Hg in the gas stream. A heated pyrolysis tube is used in this system to convert oxidized Hg compounds to elemental Hg prior to analysis for total Hg. The pyrolysis tube is bypassed to measure elemental Hg. The CEM is designed to measure the elemental Hg concentration of the gas sample, measure the total Hg concentration, perform a zero check (analysis of room air), and then re-zero the system (to correct for any instrumental drift that occurs over time). This is done in an automated, sequential measurement cycle to provide continuous monitoring of Hg concentrations in the stack gas. The continuous sampling Hg CEM was tested at the EPA-Rotary Kiln in Durham, NC at the beginning of FY02. This report describes the characteristics and performance of the system and the results of the field tests performed at EPA. The Hg CEM system was developed in response to the need of DOE and other organizations to monitor Hg that may be released during the processing or combustion of hazardous or mixed-waste materials. The promulgation of regulations limiting the release of Hg and requiring continuous monitoring of stack gases from combustion and treatment processes would seriously impact the operations of DOE waste treatment facilities. Therefore, it is important to develop and validate techniques that adequately meet proposed sensitivity and accuracy requirements. The most likely form of validation for such a technique involves comparison of CEM results with a reference test method for a test combustion system. Therefore, the CEM system was tested at EPA by monitoring Hg emissions in a natural gas combustion exhaust (that was spiked with Hg) while simultaneously collecting samples using the Ontario-Hydro mercury speciation method as the reference method. The CEM results were available continuously during the on-line monitoring that was performed. The results of the reference method sampling were received a number of weeks after the testing at EPA. These results are discussed in this report, with a comparison and evaluation of the reference method and Hg CEM data.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".