Many difficulties have been encountered in safe and efficient abatement of the many varieties of VOCs (volatile organic compounds) present in large volume and low concentration in effluent gas. The authors propose the utilization of a VOC concentrator operating on the thermal swing adsorption ora honeycomb rotor adsorbent of hydrophobic zeolite. As a design and operation guide to industrial practice, discussion covers selection of appropriate honeycomb rotors, rotor dimensions and fluid velocity, flow rate ratio of process zone to regeneration zone, and optimum rotation Speed. A new hydrophobic zeolite rotor was developed by reducing the silica sol binder by half to avoid the deterioration of performance due to accumulation of high boiling point VOCs. The amount of VOC's adsorbed by the deteriorated rotor was reached LIP to 90% of that of the virgin rotor by regeneration at high temperature of 300 degrees C. Seal structure was also improved to allow long-term operation with high-temperature regeneration, and thus a high-performance VOC concentrator incorporating the new honeycomb rotor was put into operation.