Heat recovery steam generator and method for fast starting combined cycles
US8820078B1 · kind B1 · utility
Inventor
Key dates
| Filing date | Aug 6, 2013 |
| Grant date | Sep 2, 2014 |
| Priority date | — |
| Expiry date | Sep 16, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E20/16
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.