Patent ID: 8241596

Claim:
Trap apparatus, comprising: a housing enclosing a trap chamber between an inlet conduit and an outlet conduit; a trap core comprising a heater assembly positioned in a center portion of the trap chamber and a trap medium in an inner portion of the trap chamber surrounding the heater assembly; a trap medium positioned in the inner portion of the trap chamber around the heater assembly; an inner wall around the inner portion of the trap chamber separating the inner portion of the trap chamber from an intermediate portion of the trap chamber, which surrounds the inner portion of the trap chamber; an intermediate wall around the intermediate portion of the trap chamber and spaced radially outwardly from the inner wall, thereby separating the intermediate portion of the trap chamber from an outer portion of the trap chamber and enclosing an annular counterflow heating duct between the inner wall and the intermediate wall; an outer wall around the outer portion of the trap chamber and spaced radially outward from the intermediate wall and enclosing a pre-heating duct between the intermediate wall and the outer wall, wherein the inlet conduit is connected in fluid-flow relation to an upper end of the pre-heating duct, a lower end of the pre-heating duct is connected in fluid-flow relation to a lower end of the counter-flow heating duct, an upper end of the counter-flow heating duct is connected in fluid-flow relation to an upper end of the inner portion of the trap chamber, and a lower end of the inner portion of the trap chamber is connected in fluid-flow relation to the outlet conduit.