In an exhaust duct and a boiler, there are provided: a flue gas duct through which flue gases pass; a first hopper provided to the flue gas duct, the first hopper collecting PA in the flue gases; a low-repulsion section provided to the upstream side or the downstream side of the first hopper in the direction of flow of the flue gases, the low-repulsion section having a lower coefficient of repulsion than the inner wall surface of the flue gas duct; and a popcorn-ash-trapping section for trapping PA in the flue gases, the popcorn-ash-trapping section provided to the downstream side of the first hopper and the low-repulsion section in the direction of flow of the flue gases, whereby it is possible for solid particles in the flue gases to be properly trapped.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

An interchangeable enclosed combustor for combustion of vapors includes: an interchangeable multi-paneled, multi-tiered combustor housing having a plurality of panels coupled together in polygonal form and further arranged in multiple tiers of polygonal forms, thereby to form a vertical, columnar, polygonal stack to flame combust combustible vapors; and a burner manifold disposed within the vertical, columnar, polygonal stack to flame combust combustible vapors to reduce toxic emissions. The burner manifold natural draft burners and nozzles are configured to the ratio of air and fuel to mix to achieve stoichiometric combustion and reduce harmful emissions at a rate >98% destruction efficiency and inlet pressure of <1 oz./in2. The burner manifold includes at least one orifice of a predetermined size through which to draw fuel into a plurality of mixing chambers where air is drawn in through multiple stages of air intake ports that are sized based upon fuel type and pressure.

An interchangeable enclosed combustor for combustion of vapors includes: an interchangeable multi-paneled, multi-tiered combustor housing having a plurality of panels coupled together in polygonal form and further arranged in multiple tiers of polygonal forms, thereby to form a vertical, columnar, polygonal stack to flame combust combustible vapors; and a burner manifold disposed within the vertical, columnar, polygonal stack to flame combust combustible vapors to reduce toxic emissions. The burner manifold natural draft burners and nozzles are configured to the ratio of air and fuel to mix to achieve stoichiometric combustion and reduce harmful emissions at a rate >98% destruction efficiency and inlet pressure of <1 oz./in2. The burner manifold includes at least one orifice of a predetermined size through which to draw fuel into a plurality of mixing chambers where air is drawn in through multiple stages of air intake ports that are sized based upon fuel type and pressure.

A smokeless incinerator burns unburned gas to inhibit generation of black smoke. The incinerator contains a first combustion chamber with a main combustor having firebrick walls into which waste is thrown and an auxiliary burner for burning the waste. A water cooling jacket is located above the main combustor. A second combustion chamber is located on top of the first combustion chamber and has a re-burning burner for unburned gas. A filter-equipped combustion chamber is aligned with and adjacent the second combustion chamber and has a ceramic filter. A third combustion chamber is aligned with and adjacent to the filter-equipped combustion chamber and has a dust collection cyclone. A fourth combustion chamber is located on top of the third combustion chamber and has a re-burning burner for unburned gas. An exhaust stack is located on top of the fourth combustion chamber and has a forced exhaust.

A smokeless incinerator burns unburned gas to inhibit generation of black smoke. The incinerator contains a first combustion chamber with a main combustor having firebrick walls into which waste is thrown and an auxiliary burner for burning the waste. A water cooling jacket is located above the main combustor. A second combustion chamber is located on top of the first combustion chamber and has a re-burning burner for unburned gas. A filter-equipped combustion chamber is aligned with and adjacent the second combustion chamber and has a ceramic filter. A third combustion chamber is aligned with and adjacent to the filter-equipped combustion chamber and has a dust collection cyclone. A fourth combustion chamber is located on top of the third combustion chamber and has a re-burning burner for unburned gas. An exhaust stack is located on top of the fourth combustion chamber and has a forced exhaust.

A combustor wall is provided for a turbine engine. The combustor wall includes a combustor shell and a combustor heat shield that is attached to the shell. The heat shield includes a first panel and a second panel that sealingly engages the first panel in an overlap joint. A cooling cavity extends between the shell and the heat shield and fluidly couples a plurality of apertures in the shell with a plurality of apertures in the heat shield.

A combustor wall is provided for a turbine engine. The combustor wall includes a combustor shell and a combustor heat shield that is attached to the shell. The heat shield includes a first panel and a second panel that sealingly engages the first panel in an overlap joint. A cooling cavity extends between the shell and the heat shield and fluidly couples a plurality of apertures in the shell with a plurality of apertures in the heat shield.

The corrosion and erosion resistance of ceramic heat shield elements is improved by the use of yttrium oxide on aluminum oxide as a layer or substrate material is provided. A heat is disclosed having aluminum oxide in the substrate or as a layer on a substrate, wherein yttrium oxide, particularly only yttrium oxide, is present as the outermost layer, particularly directly on the aluminum oxide.