Handbook of Solvents - George Wypych - ChemTech - Ventech!

1544 Isao Kimura
Table 22.2.1. Application data. Activated carbon fluidized bed adsorption process
Solvents Manufacturing plants Flow rate, m 3 /min Feed conc., ppm
phenol, naphthalene semiconductors 50 100*
curry odor food processing 240 4,000
IPA, phenol, acetone, ethanol electronics 120 220
terpineol IC 300 30
dichloromethane semiconductors 80 500
IPA, xylene semiconductors 150 110
IPA semiconductors 80 200
manure odor fertilizers 600 3,000*
phenol, formaldehyde, ammonia shell mold casting 2,000 4
butyl acetate, IPA, etc. semiconductors 420 50
terpineol IC 300 30
butyl acetate, etc. solvents 550 50
*odor concentration
22.2.2 APPLICATION OF MOLECULAR SIEVES
Molecular sieves is a term synonymous in this context to aluminosilicate hydrate also called
zeolite. The zeolite is applied to deodorization, gas separation and some other processes.
Since this material is, unlike activated carbon, non-combustible, it has increasingly been applied
to concentrate volatile organic compounds, VOC. The concentration process discussed
here applies to the “VOC concentrator” developed by Seibu Giken Co. Ltd. Japan. 2
The element referred to here as the VOC concentrator is non-combustible and has a honeycomb
structure. The key features are summarized below.
Key features of honeycomb rotor concentrator
• Hydrophobic zeolite is embedded into a calcinated ceramic honeycomb substrate
with an inorganic binder and recalcinated at high temperature to improve the
compatibility of zeolite with the ceramic substrate.
• Various types of VOCs can be efficiently purified and concentrated.
• The most suitable zeolite and composition are selected for application.
• Absorption medium is non-combustible
• Heat resistance up to 500°C
• Desorption temperature: 150 - 220°C
Functions of the VOC concentrator
(1) Purification - The VOC laden exhaust air stream is purified by zeolite or other adsorbent
while passing through the rotor, and the purified air stream is vented into the atmosphere.
(2) Concentration - The VOC laden exhaust air stream is adsorbed in the process zone
and desorbed in the desorption zone into a heated desorption air stream with much less air
volume than that of process air stream. The VOC is concentrated nearly equal to the air volume
ratio (5-15) of the process and desorption (QP/QD).