High temperature sub-critical boiler with steam cooled upper furnace and start-up methods
US9920924B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2016 |
| Grant date | Mar 20, 2018 |
| Priority date | — |
| Expiry date | May 13, 2036 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF22G7/14
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A boiler is disclosed in which the furnace is divided into a lower furnace and an upper furnace. The lower furnace uses water-cooled membrane walls, while the upper furnace uses steam-cooled membrane walls that act as superheating surfaces. A steam-cooled circuit includes a steam separator, a primary superheater, and the steam-cooled membrane walls of the upper furnace. During start-up, a diversion path is opened that reduces dry steam flow through the primary superheater and increases dry steam flow through the steam-cooled membrane walls of the upper furnace. This protects the steam-cooled membrane walls from excessive thermal stresses during start-up.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.