The most fuel efficient configuration is to integrate Zeolite rotor concentrators with a Regenerative Thermal Oxidizer (RTO) for VOC destruction.
Dual Chamber RTOs with 95% primary heat recovery and flameless Natural Gas Injection (NGI) can operate autothermally with highly concentrated VOC streams from concentrators. High airflow applications such as automotive and aerospace finishing take advantage of the minimal fuel requirements of this configuration. Gas fired heaters can be used for rotor regeneration. However, using hot gas bypass air from the RTO can almost eliminate only fuel usage for the system during normal operating hours. The only fuel use would be at startup.