The purpose of this pilot-scale test of ozone-enhanced catalytic oxidation technology at Domtar Kraft pulp and paper mill was to investigate the treatment of high volume, low concentration waste gas streams at their source. The waste gas stream contained volatile organic compounds (mainly methanol (460 ±230 ppm)) and total reduced sulfur compounds (dimethyl sulfide = 5500 ± 2300 ppm, dimethyl disulfide= 170 ± 86 ppm). The study followed long developmental work on bench-scale studies using synthetic waste gas containing methanol and dimethyl sulfide. In the bench-scale studies, moisture effects on the reaction were minimal, and there was no observable deactivation of catalyst. Ozone-enhanced catalytic oxidation has low capital and operating costs and does not require major changes in the pulping process. It can be "dropped-in" using existing infrastructure with little disruption with the core process. The process eliminates the frequent flameout problems at the incinerator, due to the low fuel value of blow gas and stripper overhead gas streams. Although the technology appeared to be feasible at the lab scale, the field study data revealed that several obstacles must be overcome prior to this technology being implemented in large-scale. Insufficient destruction efficiencies for the organic and TRS compounds were observed in the field study for this technology, and so at its current state of development, it cannot be considered as a replacement for incineration. The presence of value-added materials from partial oxidation products was not observed. Ozone / sulfur ratios > 2, space velocities < 1000 hr~(-1), and reaction temperatures > 200 C are required to achieve >90% destruction of dimethyl sulfide in the high volume low concentration waste gas stream formed in the pulping area of an integrated Kraft mill.
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