| 1. |
- Bidgoli, Hosein, 1987, et al.
(författare)
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Terahertz Spectroscopy for Real-Time Monitoring of Water Vapor and CO Levels in the Producer Gas From an Industrial Biomass Gasifier
- 2014
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Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 4:6, s. 722-733
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present a study of THz transmission spectroscopy as a novel tool for the monitoring of the steam and CO contents of the raw gas from industrial biomass gasifiers. A THz gas spectrometer with a frequency range of 300–500 GHz was designed and constructed. Proof-of-principle testing was performed at laboratory conditions using mixtures of different gases at high temperatures (600–700 K). The results demonstrate the feasibility of applying strong rotational water vapor lines at 448 and 383 GHz, so as to obtain reliable online measurements of water vapor with an absolute precision of about 0.2 vol.% for the current device. CO lines were identified at 461 and 346 GHz, facilitating measurement of this gas. The gas spectrometer was integrated into an industrial gasifier and boiler, and its performance was tested in terms of online measurements of steam and CO in the hot raw gas and flue gases under real-life conditions. Considering the error intervals, the results are in complete agreement with data acquired by solving loose mass balances around the system. The onsite experiments demonstrate that THz gas spectroscopy is a promising tool for fast, robust, and reliable monitoring in industrial applications.
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| 2. |
- Cherednichenko, Serguei, 1970, et al.
(författare)
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Online water vapor detection in the product gas from indirect gasification
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The integration of a gasifier into a complex synthesis process, such like SNG synthesis,with several process steps asks for a better monitoring of the gasifier performance.While the dry gas composition is often known, tar concentration andsteam concentration in the raw producer gas are usually not available online. A setof standard analyzers for dry gas composition (GC or NDIR) and online tar measurementcombined with an online water measurement could allow the continuouscalculation of simple mass and energy balances. Those balances, that characterizethe gasification process, could enable the operator to monitor the effects ofvarying fuel properties and eventually counter the effects on the downstreamequipment.For the detection of steam concentration in raw gas electromagnetic waves ofterahertz frequencies (hundreds of gigahertz) are promising with regard to developa robust online measurement device for industrial application. Main reasons for thehigh potential are the low risk for interference with the wide range of other moleculesand the fact that THz frequencies are rather insensitive to deposits and particulatematter in the course of the beam, compared to laser technology at IR.Aiming to test the feasibility of applying this measurement technique in the industrialscale, a gas cell was designed and constructed providing conditions close tothe onsite operation (i.e. T, P, gas composition, etc.) for primary laboratory tests.The experiments were then followed with onsite tests at Chalmers power central.Within those experiments the application of THz spectroscopy as a promisingtechnique for detection and measurement of steam and CO at real industrial processeswas proven. Current report demonstrates the procedure of implementing aTHz spectrometer to acquire data in both laboratory and industrial scale and discusshow those data could be interpreted to gain a precise measurement of desiredgaseous components.
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| 3. |
- Cherednichenko, Serguei, 1970, et al.
(författare)
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Online Detection of H2O and CO in the Humid Raw Gas from the Gasifier Using Terahertz Spectroscopy
- 2013
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Ingår i: ICPS, 13 International Conference on Polygeneration Strategies, Sept.5-13, Vienna, Austria. - 9783950275483 ; , s. 51-58
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Konferensbidrag (refereegranskat)abstract
- The integration of a gasifier with a complex multistage synthesis process, such as SNG synthesis, demands a fast monitoring of the gasifier performance. However, despite the availability of standard analyzers for determination of dry gas composition, there are still many practical difficulties remaining in the online measurement of tar and steam in the raw gas. For the detection of steam concentration, electromagnetic waves at terahertz frequencies (102-104 GHz) are promising with regard to development of a robust online measurement device for industrial application. The main reason for the high potential is the low risk for interference with the wide range of other molecules and that the transmission of electromagnetic waves at THz frequencies is rather low sensitive to deposits and particulate matter in the course of the beam compared to the conventional and well established wavelengths like infrared. In the present work, a THz gas spectrometer was designed and constructed to check the feasibility of applying this measurement technique at industrial scale. For this purpose, continuous flows of raw gas with various water and CO contents from the Chalmers gasifier as well as a flue gas with known water content from the biomass combustor were introduced to the spectrometer set-up. H2O and CO compositions in each stream were determined in an online manner. The results confirmed the possibility of applying strong rotational water lines at 448 and 380 GHz to develop reliable devices for online measurement of water vapor with excellent error interval. However, some difficulties were encountered for simultaneous detection CO concentration with water within the frequency range studied in this work (300-500 GHz).
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| 4. |
- Cherednichenko, Serguei, 1970, et al.
(författare)
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Terahertz Gas Spectrometer
- 2014
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Ingår i: Swedish Microwave Days March 11-12, 2014, Gothenburg, Sweden.
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Konferensbidrag (refereegranskat)abstract
- We present a 300-500GHz gas spectrometer built for and practically tested at the 2–4-MW indirect gasifier at the Chalmers Power Center. The primary goal is precise online measurements of H2O vapor and CO concentrations in the producer gas. Experimentally obtained H2O vapor concentration resolution was about 1% at the conditions of 50% VMR and 400 deg.C.
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