Honeycomb rotor

One way to improve the performance of photocatalytic air-treatment reactors is to decouple between cleaning the air and degrading the pollutants. Figure 14 shows schematically such a system (Chin et al., 2006 Shiraishi et al., 2003). The system includes two independent continuous flow systems interconnected by a rotating, cylindrical ceramic honeycomb. The rotation cycles the honeycomb rotor through a low temperature zone, where adsorption takes place, and a high temperature zone where desorption takes place, thus regenerating the monolith. The contaminated air flows... 

T. Hirose and T. Kuma, "Honeycomb rotor continuous adsorber for solvent recovery and dehumidification, 2nd Korea-Japan Symp. on Separation Technology (1990). 

With this experiment, the proper type of adsorbent and the amount of impregnation was determined, and the operation parameter such as adsorption / desorption / cooling area ratio, rotational speed, required size of VOC adsorbing honeycomb rotor was designed... 

Organic binder in ceramic honeycomb rotor was removed by heating it for 5 hrs in 600 C before impregnation of zeolite. Heat treated rotor was soaked in zeolite (UOP HISIV 1000 and HISIV 3000) dispersed slurry with silica sol (Nissan Chemical ST-30) or alumina sol (Nissan Chemical AS-520) as a binder. The amount of binder addition was vairied to 3, 5, 7 wt%. BET surface area and SEM micrograph was analyzed with respect to type of binder and its amount. 

Kodama A., Goto M., Hirose T. and Kuma T., Temperature profile and optimal rotation speed of a honeycomb rotor adsorber operated with thermal swing, J. Chem. Eng. Japan 27 (1994) pp. 644-49. 

Recently, rotor-type adsorption systems attract much attention, because the systems can effectively control humidity and air pollutants such as volatile organic compounds (VOCs), nitrogen oxide (NOx) and sulfiuic oxide (SOx). Gas remediation efficiency is principally concerned to the gas capturing ability of the adsorbents impregnated into the ceramic honeycomb rotor such as zeolite, silica, activated carbon, etc. Therefore, it is one of the most important works to develop the adsorbent with good absorption-desorption behaviors. 

In the photoresist segment of the semiconductor process a very low concentration of VOC is generated. These low eoncentration VOCs can be removed by a concentration step followed by a catalytic oxidation process. The industrial application of this method is discussed below. Dilute VOC is fed to the rotating zeolite concentrator discussed in Section 22.2.2 (honeycomb rotor) where it is concentrated to 10 times of the original concentration and burned on catalysts at relatively low temperature. This saves fuel cost. The VOC is a mixture of IP A, acetone, MEK, toluene, ethyl acetate, n-hexane, propylene glycol monoethyl eflier, propylene glycol monoethyl ether acetate, andtetramethyl ammonium hydroxide. Themix-... 

HMDS), phosphorous-compounds and halogen-compounds which are all catalyst poisons. The pretreated gas is fed to the zeolite honeycomb rotor for concentration. (Figure 22.2.4)... 

Figure 1. Ceramic honeycomb rotor formed with ceramic paper...

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