Raw gas/purified gas heat exchanger

Claim 1

Raw gas/purified gas heat exchanger for hot dust-laden raw gas, comprising: (a) a substantially vertical channel which is open at the bottom (b) a raw gas inlet line to the top of the channel for the introduction therein of hot dust-laden raw gas (c) heat exchanger tubes through which purified gas flows disposed in the vertical channel with the tubes arranged in different two-dimensional planes extending parallel to each other and to a symmetry axis of the channel (d) a vessel with a funnel-shaped bottom wherein the channel together with the heat exchanger tubes are arranged, said vessel is closed on all sides is provided at the upper end of the vessel with a raw gas discharge line which surrounds the raw gas inlet line concentrically (e) an input plenum connected at the lower end of the channel to the heat exchanger tubes, and a discharge plenum connected at the other end of the channel to the heat exchanger tubes (f) an ash discharge device connected to the lowest point of the bottom of the vessel, and (g) wherein the input plenum is arranged exterior of the channel but within the vessel.