Automatic draft control system for coke plants
A coke oven includes an oven chamber, an uptake duct in fluid communication with the oven chamber, the uptake duct being configured to receive exhaust gases from the oven chamber, an uptake damper in fluid communication with the uptake duct, the uptake damper being positioned at any one of multiple positions, the uptake damper configured to control an oven draft, an actuator configured to alter the position of the uptake damper between the positions in response to a position instruction, a sensor configured to detect an operating condition of the coke oven, wherein the sensor includes one of a draft sensor, a temperature sensor configured to detect an uptake duct temperature or a sole flue temperature, and an oxygen sensor, and a controller being configured to provide the position instruction to the actuator in response to the operating condition detected by the sensor.
1. A coke oven, comprising:
an oven chamber;
an uptake duct in fluid communication with the oven chamber and configured to receive exhaust gases from the oven chamber;
an uptake damper in fluid communication with the uptake duct and configured to be positioned at one of a plurality of positions including fully opened and fully closed, wherein, in operation, the position of the uptake damper controls an oven draft;
an actuator configured to alter the position of the uptake damper between the plurality of positions in response to a position instruction;
a plurality of coke oven sensors each configured to detect an operating condition of the coke oven, wherein the plurality of sensors comprises a draft sensor configured to detect the oven draft, a temperature sensor configured to detect an uptake duct temperature or a sole flue temperature, and an oxygen sensor configured to detect an uptake duct oxygen concentration in the uptake duct; and
a controller in communication with the actuator and with the plurality of sensors, such that the controller receives a signal from each of the plurality of sensors that corresponds to a measured process value of the coke oven, the controller being configured to provide the position instruction to the actuator, based at least in part on signals received from each the plurality of sensors over a period of time, wherein providing the position instruction causes the actuator to alter the position of the uptake damper and maintain the oven draft at or above a predetermined target oven draft for the coke oven, wherein the target oven draft varies over a duration of a coking cycle based on an elapsed time of the coking cycle, such that the target oven draft is adjusted (i) a first time period after a beginning of a coking cycle, and (ii) a second time period after the first time period has elapsed.
2. The coke oven of claim 1 , wherein providing the position instruction to the actuator occurs over an entire duration of a coking cycle.
3. The coke oven of claim 1 , wherein at least one of the sensors is positioned in the oven chamber.
4. The coke oven of claim 3 , wherein at least one of the sensors is positioned in the sole flue.
5. The coke oven of claim 1 , wherein providing the position instruction causes the actuator to alter the position of the uptake damper and allow excess air into the oven in response to an overheat condition detected by the temperature sensor.
6. The coke oven of claim 1 , wherein the temperature sensor is positioned in the uptake duct.
7. The coke oven of claim 1 , wherein providing the position instruction causes the actuator to alter the position of the uptake damper to thereby maintain the uptake duct oxygen concentration within an oxygen concentration range.
8. The coke oven of claim 1 , wherein the oxygen sensor is positioned in the uptake duct.
9. The coke oven of claim 1 , wherein providing the position instruction is based at least in part on maintaining the oven draft at least at 0.1 inches of water.
10. The coke oven of claim 1 , wherein the controller is further operative to vary the targeted oven draft over a coking cycle by stepwise reducing the target oven draft as a function of elapsed time.
11. A coke plant, comprising:
a plurality of coke ovens each including—
an oven chamber;
an uptake duct in fluid communication with the oven chamber and configured to receive exhaust gases from the oven chamber;
an uptake damper in fluid communication with the uptake duct and configured to be positioned at one of a plurality of positions including fully opened and fully closed, wherein, in operation, the position of the uptake damper controls an oven draft;
an actuator configured to alter the position of the uptake damper between the plurality of positions in response to a position instruction; and
a plurality of sensors including a draft sensor configured to detect the oven draft, a temperature sensor configured to detect an uptake duct temperature or a sole flue temperature, and an oxygen sensor; and
a controller in communication with each of the actuators and the plurality of sensors of the plurality of coke ovens, the controller being configured to automatically control the uptake damper of each coke oven, based at least in part on signals received from each of the plurality of sensors for the respective coke oven, wherein automatically controlling the uptake dampers causes the oven draft to be maintained at or above a targeted oven draft, wherein the target oven draft varies over a duration of a coking cycle based on an elapsed time of the coking cycle, such that the target oven draft is adjusted (i) a first time period after a beginning of a coking cycle, and (ii) a second time period after the first time period has elapsed.
12. The coke plant of claim 11 , wherein automatically controlling the uptake damper of each coke oven comprises automatically adjusting a position of the respective uptake damper between one of a plurality of positions including fully opened and fully closed.
13. The coke plant of claim 12 , wherein automatically controlling the uptake damper of each coke oven comprises providing position instructions to automatically adjust a position of the respective uptake damper between one of a plurality of positions, and wherein providing the position instruction causes the actuator to alter the position of the uptake damper such that, in operation, excess air enters into the oven in response to an overheat condition detected by the temperature sensor.
14. The coke plant of claim 11 , wherein the controller is further operative to time-average differences in operating conditions detected by the respective plurality of sensors.
15. The coke plant of claim 14 , wherein position instructions provided by the controller are linearly proportional to the differences in the time-averaged operating conditions detected by the respective plurality of sensors.
16. The coke plant of claim 14 , wherein position instructions provided by the controller are non-linearly proportional to the differences in the time-averaged operating conditions detected by the respective plurality of sensors.
17. The coke plant of claim 11 , wherein the controller is further operative to maintain a constant time-averaged oven draft within a predefined tolerance of the target oven draft throughout a coking cycle.
18. The coke plant of claim 11 , wherein automatically controlling the uptake damper of each coke oven occurs over an entire duration of a coking cycle.
19. The coke plant of claim 11 , wherein at least one of the sensors is positioned in the oven chamber and at least one of the sensors is positioned in the sole flue.
20. The coke oven of claim 11 , wherein the temperature sensor is positioned in the uptake duct.