Method and apparatus to reduce thermal stress when starting combined cycle power systems

    公开(公告)号:US20190072006A1

    公开(公告)日:2019-03-07

    申请号:US15731989

    申请日:2017-09-05

    IPC分类号: F01K13/02 F01K23/10 F22D1/00

    摘要: Apparatus and method to wet start the HRSG and combined cycle in the fastest time with minimum thermal stress. This wet start provides the earliest possible cooling steam during acceleration, reducing stress in the superheater, reheater and steam turbine. The gas turbine is started and loaded to full power in the fastest possible time without holds. A once-through HRSG filled with saturated boilerwater including the superheater generates dry steam during acceleration. Start apparatus positions the dryout zone in each superheater tube, controls surge swell, ensures uniform pressure rise, and controls the steam temperature. The superheater generates temperature controlled steam to cool the tubes while heating headers. Superheater and reheater tubes and headers start at saturation and increase to operating with minimum differential temperatures. The superheater evaporating boilerwater supplies constant low temperature dry steam to start the steam turbine without the use of attemporators.

    Methods and apparatus for fast starting heat recovery steam generators for combined cycle power plants

    公开(公告)号:US20220381158A1

    公开(公告)日:2022-12-01

    申请号:US17300366

    申请日:2021-06-01

    IPC分类号: F01K13/02 F01K23/10 F22B1/18

    摘要: A fast HRSG starting method and apparatus for combined cycles requiring frequent cycling, baseload and backup power; preventing grid failure from variables of wind and solar power. A once-through HRSG, eliminating all except two hot thick wall components: the high pressure superheater and reheater headers. The method fills the high pressure superheater with boilerwater; whereby steam is generated in starting as thick header's and tube's ramp-up together at saturation temperatures as the gas turbine attains synchronous speed No-Load; reducing conventional thermal stress failures loss of availability and costly repairs. At gas turbine full power dry steam is generated by the high pressure superheater at low allowable temperature start and load the steam turbine and protect the reheater. The dryout zone in the high pressure superheater is controlled loading the steam turbine faster than conventional without problematic attemperators, thereby decreasing: thermal stresses, fuel, emissions and possible ingestion of spray-water.

    Heat recovery steam generator and method for fast starting combined cycles
    3.
    发明授权
    Heat recovery steam generator and method for fast starting combined cycles 有权
    热回收蒸汽发生器和快速启动联合循环的方法

    公开(公告)号:US08820078B1

    公开(公告)日:2014-09-02

    申请号:US13987540

    申请日:2013-08-06

    摘要: A once-through high pressure steam generator and reheater configured to eliminate the majority of components limiting cyclical life of fast start conventional HRSGs. Two remaining problematic components in conventional designs the final superheater and reheater tubes overheat while their headers remain colder in fast starts. In this inventive HRSG the critical components are arranged and started by a method that limits these damaging temperature differentials. At ignition when exhaust gas surges into a wet superheater steam flow starts minutes before conventional systems. This early steam flow cools the tubes while heating the headers, thereby reducing life damaging stresses. Steam temperature is controlled through the start and warms the rest of the plant earlier without attemperators with their problematic thermal stress history. Faster starts than conventional result without damaging fatigue life depletion with this low cost innovation.

    摘要翻译: 一个一次通过的高压蒸汽发生器和再加热器被配置为消除大多数部件限制快速启动常规HRSG的循环寿命。 传统设计中的两个剩余的问题组件是最终的过热器和再热器管过热,而它们的头部在快速启动时保持较冷。 在本发明的HRSG中,通过限制这些有害温度差的方法来布置和启动关键部件。 当点火时,当废气涌入潮湿的过热器时,蒸汽流在常规系统之前开始分钟。 这种早期的蒸汽流在加热集管时冷却管,从而减少寿命损坏的应力。 蒸汽温度通过启动进行控制,并且在没有调温器的情况下加热其他工厂的其余部分,并且遇到有问题的热应力历史。 通过这种低成本创新,比传统结果更快地启动,而不会损坏疲劳寿命。