초록 ▼

A compact, unfired, staggered tube, once-through steam generator or boiler of simple construction intended primarily for combined cycle power plants in which the thermal energy utilized to generate steam is obtained from the exhaust gases of a gas turbine engine. The boiler provides steam at two dif

A compact, unfired, staggered tube, once-through steam generator or boiler of simple construction intended primarily for combined cycle power plants in which the thermal energy utilized to generate steam is obtained from the exhaust gases of a gas turbine engine. The boiler provides steam at two different pressure levels, which maximizes recovery of thermal energy; and all wettable components in the steam/water loop are fabricated of corrosion resistant materials. This eliminates the need for controlling the pH of the feedwater and the need for chemically controlling its dissolved oxygen content, thereby reducing maintenance and operating costs and making automatic, unattended, remotely controlled operation of the boiler practical as well as eliminating the need for blowing down the boiler and minimizing requirements for make-up water. The boiler can be operated dry to remove gas side fouling; and feedwater flow rates can be directly controlled. Orifice-generated pressure drops at the inlets of the boiler tubes which are relatively large compared to the pressure drop in the rest of each tube eliminate the flow instability that is characteristic of once-through boilers.

대표청구항 ▼

A combined cycle power plant comprising: a gas turbine engine; a once-through boiler; means for effecting a flow of feedwater into said boiler; means for effecting a flow of exhaust gases from said gas turbine engine through said once-through boiler to convert said feedwater to steam; a steam turbin

A combined cycle power plant comprising: a gas turbine engine; a once-through boiler; means for effecting a flow of feedwater into said boiler; means for effecting a flow of exhaust gases from said gas turbine engine through said once-through boiler to convert said feedwater to steam; a steam turbine; and means for effecting a flow of the steam generated in said boiler to said steam turbine to drive the latter, said once-through boiler comprising: a vertical casing having a gas inlet and a gas outlet respectively located at the lower and upper ends thereof; an overhead support structure in said casing; a plurality of independent steam generating circuits hung from said support structure, each of said circuits comprising a single, sinuous low pressure tube with horizontal tube runs and a high pressure tube of similar configuration internested with the low pressure tube, said horizontal tube runs being so staggered as to increase the transfer of heat from hot gases flowing upwardly through said casing to said high and low pressure tubes and said high pressure tubes each having feedwater, vaporizer, and superheater sections with said vaporizer and superheater sections being of greater diameter than the feedwater sections; and a feedwater pump for effecting a flow of water into said low and high pressure tubes at the inlet ends thereof.