Abstract: A suppression chamber in a nuclear reactor containment includes a heat exchanger disposed in a gas space above water in the suppression chamber. A gravity-driven pool contains a supply of make-up water that is gravity fed to the heat exchanger through a conventional level-maintaining valve such as a float valve. A top header in the heat exchanger includes a free surface area for permitting separation of steam from water, thereby permitting venting of vapor only, while retaining the liquid coolant in the heat exchanger. A downcomer tube permits return of excess water to a lower location for further use in the heat exchanger. The heat exchanger is normally sealed, whereby internal surfaces in the heat exchanger require only a small amount of low-volatility corrosion inhibitors to prevent corrosion on internal surfaces thereof. Locating the heat exchanger in the gas space in the suppression chamber reduces the amount of corrosion on its external surfaces.

Abstract: There is disclosed a boiler system in which ash-bearing fuels are fired in horizontal suspension and in which provision is made for the removal of the ash without shutting down or reducing the output of the system. The system comprises an upper water and steam drum and at least one lower water drum. A furnace cavity is located substantially between the upper drum and the lower drum, with the cavity being defined by a pair of side walls, a front wall, a rear wall, a ceiling and a floor. Means in the form of openings in the floor of the furnace cavity are located near the rear wall of the furnace cavity for permitting ash to be removed from the boiler system without requiring the shutting down or the reduction of the output of the boiler system.