Method and apparatus for removing deposit from recovery boilers
US5113802A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 1991 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Mar 26, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF28G13/00
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for removing salt-cake deposits from boiler surfaces found in the upper areas of recovery furnaces. More specifically, in the Kraft papermaking process, a black liquor is produced which is combusted in a recovery furnace in order to supply heat for steam generation. Hot flue gases containing inorganic salt combustion by-products are passed through and around boiler heat exchange tubes found in the upper furnace areas. Deposits of the inorganic salt components are formed on the heat exchange tubes, thus insulating the tubes from the hot flue gases and resulting in lower heat recovery boiler efficiency. A laser is mounted proximate the furnace such that a high energy beam of coherent light generated by the laser is directed to the heat exchange tubes of the boiler found within the furnace, whereby the beam contacts the deposits which insulate the heat exchange tubes, thereby causing a change in the structure of the salt-cake leads to physical degradation of the deposit, thus allowing removal of the deposit layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.