In this study, a two-bed electrically-heated regenerative catalytic oxidizer (RCO)
was used to test the destruction characteristics in burning toluene-borne air
streams. The RCO contained two 0.152 m¡Ñ0.14 m¡Ñ1.0 m (L ¡Ñ W ¡Ñ H) beds,
both packed with gravel particles with an average diameter of around 0.0111 m
and a height of up to 0.875 m with a void fraction of 0.42 in the packed section.
In addition, in each column catalytic particles with an average diameter of
around 0.008 m were packed over the gravel particles to a height of 0.125 m.
Gas temperature rise and the gas pressure drop over the beds were also studied.
Experimental results reveal that, with a valve shifting time (ts) of 1.5 min,
superficial gas velocities (Ug) of 0.39 and 0.86 m/s (evaluated at an influent air
temperature of around 30 oC) and preset maximum destruction temperatures (TS)
of 300-400 oC, only around 25% of the influent toluene (Co = 200-400 ppm) was
thermally destructed with no catalyst in both beds. With the cartalyst packings
and operation conditions of Ug = 0.39 m/s and Co = 200-800 ppm, destruction
efficacies of around 80.9¡Ó0.8, 94.6¡Ó1.8, and 98.1¡Ó0.2 % were observed,
respectively, at TS of 250, 300, and 400 oC. At Ug = 0.86 m/s and Co = 200-800
ppm, destruction efficacies of around 69.7¡Ó3.1, 93.9¡Ó1.7, and 97.8¡Ó0.4 % were
observed, respectively, at TS of 250, 300, and 400 oC. It is suggested that
operation conditions with Ug = 0.39-0.86 m/s (equivalent to
empty-bed-residence times of 0.29-0.64 s for the gas at 30oC through the
catalyst beds) and TS = 300 oC are suitable for the destruction of around 98% of
the influent air with 200-800 ppm toluene. Gas temperature rises of 21 and 26
oC, respectively, were found for Ug = 0.39 and 0.86 m/s with TS = 300 oC. The
Ergun equation was found to suffice in the estimation of the pressure drop when
the gas flowed over the packing beds.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0726107-192123 |
| Date | 26 July 2007 |
| Creators | han, Liu-yen |
| Contributors | none, none, none |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0726107-192123 |
| Rights | campus_withheld, Copyright information available at source archive |
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