Ash bed level control system for a fixed-bed coal gasifier
Abstract
An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate. A grate drive is activated to rotate a grate assembly supporting the ash bed for a period equal to the count down period to maintain the selected ash bed level. In order to avoid grate binding, the controller provides a short base operating duration timemore »
- Inventors:
-
- Morgantown, WV
- Fairmont, WV
- Issue Date:
- Research Org.:
- National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV (United States)
- OSTI Identifier:
- 865043
- Patent Number(s):
- 4453949
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
C - CHEMISTRY C10 - PETROLEUM, GAS OR COKE INDUSTRIES C10J - PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- ash; bed; level; control; fixed-bed; coal; gasifier; provided; incorporates; meter; automatically; selected; signal; updated; cycle; stirrer; travels; extent; derived; temperature; measurements; thermocouples; carried; passes; fire; zone; immediately; compared; threshold; determine; below; counter; incremented; decremented; accordingly; registered; count; preset; counted; clock; rate; grate; drive; activated; rotate; assembly; supporting; period; equal; maintain; avoid; binding; controller; provides; base; operating; duration; time; drops; exceeds; means; notify; operator; fixed-bed coal; level control; level signal; threshold level; bed level; temperature measurements; coal gasifier; coal gas; ash bed; bed coal; temperature measurement; selected level; ash level; automatically control; assembly supporting; drops below; level meter; selected threshold; clock rate; grate assembly; controller provides; temperature measure; bed stirrer; /48/422/700/
Citation Formats
Fasching, George E, and Rotunda, John R. Ash bed level control system for a fixed-bed coal gasifier. United States: N. p., 1984.
Web.
Fasching, George E, & Rotunda, John R. Ash bed level control system for a fixed-bed coal gasifier. United States.
Fasching, George E, and Rotunda, John R. Sun .
"Ash bed level control system for a fixed-bed coal gasifier". United States. https://www.osti.gov/servlets/purl/865043.
@article{osti_865043,
title = {Ash bed level control system for a fixed-bed coal gasifier},
author = {Fasching, George E and Rotunda, John R},
abstractNote = {An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate. A grate drive is activated to rotate a grate assembly supporting the ash bed for a period equal to the count down period to maintain the selected ash bed level. In order to avoid grate binding, the controller provides a short base operating duration time each stirrer cycle. If the ash bed level drops below a selected low level or exceeds a selected high level, means are provided to notify the operator.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1984},
month = {Sun Jan 01 00:00:00 EST 1984}
}