Abstract: In certain embodiments, methods, systems, and apparatus are provided for use in removing pollutants from a gas stream. The invention includes a thermal reaction unit formed from a plurality of stacked porous ceramic rings. The porous rings include perforations adapted to allow fluid to be flowed into the thermal reaction unit. By flowing fluid through the porous rings, deposition of waste effluent and/or by-products on the interior of the thermal reaction unit is prevented. Numerous other aspects are provided.

Abstract: In certain embodiments, an apparatus is provided for use in removing pollutants from a gas stream. The apparatus includes a thermal reaction unit formed from a plurality of stacked porous ceramic rings. At least one of the stacked ceramic sections may be adapted to allow sensing of a characteristic of contents of the central chamber. In some embodiments, waste gas inlets to the thermal reaction unit may be angled to create a helical vortex within the thermal reaction unit. Other aspects are provided.

Abstract: In certain embodiments, methods, systems, and apparatus are provided for use in removing pollutants from a gas stream. The invention includes a thermal reaction unit formed from a plurality of stacked porous ceramic rings. A first of the porous ceramic rings has a first coefficient of thermal expansion (CTE) and a second of the porous ceramic rings has a second CTE. Numerous other aspects are provided.

Abstract: In certain embodiments, an apparatus is provided for use in removing pollutants from a gas stream. The apparatus may include one or more thermal reaction units formed from a plurality of stacked porous ceramic rings. The thermal reaction units may be selectively coupled to one or more process tools. In some embodiments a manifold may be used to direct waste effluent toward online primary thermal reaction units and away from back-up thermal reaction units. If a primary thermal reaction unit goes off-line, the manifold may redirect waste effluent toward one or more of the back-up thermal reaction units. Numerous other aspects are provided.