Abstract: A modular thermal oxidizing device has a heat exchanger and a burner chamber connected to convert volatile, condensable organic compounds to harmless gasses. The heat exchanger includes an internal cold side bypass with cooling tubes extended into a hot side adjacent to the burning chamber. An appropriate aperture or hole tolerance related to the tubes as mounted within the hot side tube sheet is adopted to permit efficient expansion and contraction of the tubes without binding in the tube sheet.

Abstract: Gas consisting of air mixed with varying concentrations of solvent vapors, drawn from a dryer, is passed through controllable heating means to a catalyst bed. In flow through the catalyst bed, for oxidation of the vapors, temperature rise of the gas depends upon solvent concentration. For control of the heating means, so that gas at the bed inlet will have a temperature high enough for complete vapor oxidation but not so high as to be unnecessarily hot at the bed outlet, thermocouples are located to sense gas temperature at the bed inlet and outlet. Like terminals of the thermocouples are connected to opposite ends of a potentiometer resistance element; its slider is connected with a comparison device that compares the potentiometer output (corresponding to a weighted average of bed inlet and outlet temperatures) with a demand value. The heating means consists of a controllable fuel burner and a heat exchanger wherein hot gas from the catalyst bed can heat gas flowing to the burner.