The hottest sunypcc800 system is in the gas making

2022-08-18
  • Detail

Application of sunypcc800 system in the control of gas making section of chemical fertilizer plant

Abstract: Based on the project of gas making section of a chemical fertilizer plant, this paper introduces the typical control scheme of PCC800 in the control of gas making section of chemical fertilizer plant, and gives the application effect analysis

Keywords: PCC800; 2. Go up; Purge; Blowing; Recycling; Blowing up; Blow down; Sequence control

process and requirements

there are two gas making furnaces on the user's site, and the production process of the two gas making furnaces is the same

the gas making cycle of each gas making furnace is divided into six steps, namely: first, second; 2、 Purge; 3、 Blowing; 4、 Recycling; 5、 Blowing up; 6、 Blow down. In addition to the blowing up time, the operation setting window is required for each step, and the operation personnel can set and modify the execution time of each step according to the process conditions. The up blowing time is equal to the time after the sum of the gas making cycle time minus the execution time of other steps, which is calculated by the system. Therefore, the up blowing time does not need to be set manually until 2023

a gas making cycle timing clock is set inside the system for each gas making furnace. The timing duration of this timing clock is set and modified by the operator according to the process conditions, and the cycle timing. When the gasifier stops running, the timing clock is also in cycle timing, which is used for the blowing queue of the two gasifiers

the user requires the execution time of each step

control scheme

under the normal operation of the gasifier (the operator does not intervene), the system determines the start and end time of each step according to the timing time of the timing clock and the execution time of each step set by the operator, and executes each step in this order. In addition, the following functions are realized according to the process requirements:

I. stepping function: step from this step to the next step

1. Step function in this cycle, if the blowing valve is opened and directly steps to the down blowing, 5S up blowing should be performed before entering the down blowing

2. Step function in this cycle, if the queue clock timing does not reach or exceed the blowing set time, the step function cannot step to the blowing and recovery steps, but should directly step from blowing to blowing up

3. When stepping from this step to the next step in this cycle, the execution time of this step is correspondingly shortened, but the execution time of the corresponding step is not prolonged

II. Delay function: extend the execution time of this step

the delay function can be realized by the delay function key and the manual key. The difference is that the delay function key only executes the delay in this cycle, and it will reset automatically after this cycle is executed; The manual key can only cancel the delay manually and is not controlled by the cycle time

1. The clock meter can also program and print the experimental report according to the format required by the user; At this time, if the delay is canceled, the purge should be performed for 5 seconds first, and then the up purge should be performed for 5 seconds. If the queued clock timing is still in the down purge step in this cycle, the down purge can be performed

2. When blowing, delay until the queued clock timing reaches the next blowing step. At this time, if the delay is cancelled, the up blowing should be performed for 5 seconds first. If the queued clock timing is still in the next blowing step in this cycle, the down blowing can be performed

III. when driving, you must perform a complete two-up before stepping (except for forced opening)

IV. forced on function: the corresponding system starts to make gas from blowing, and the starting sequence is: manual key setting, forced on key setting, driving key setting. The corresponding system starts to make gas from blowing

this function can only be set in the manual key setting and parking state. And automatically reset after the execution of this cycle

v. idling function: the corresponding system idling start is interlocked with the default gas making start, and the idling key can be set only in the shutdown state

1. Set the idle key in the parking state and turn on the corresponding system idle function

2. After setting the start key, the corresponding system enters the idling system, and at this time, the idling system cannot be canceled (or reset)

3. After the idling is completed and the parking space is set, the idling can be cancelled

4 after the end of each experiment and after the corresponding system enters the idling and start-up, the full up and nitrogen reduction functions are automatically turned on (which can be manually cancelled after opening). When the nitrogen reduction function is cancelled, the system starts to recover nitrogen from the next cycle

VI. nitrogen reduction function: close the nitrogen adding valve

when the system is blowing up or down, set the nitrogen reduction key, close the nitrogen adding valve and cancel the blowing delay time. If the nitrogen reduction function is not cancelled before the end of this cycle, the recovery step is cancelled in the next cycle, and the recovery time is added to the blowing step. If the nitrogen reduction function is cancelled before the end of the next cycle, the blowing delay time will be restored and the recovery step will be resumed from the next third cycle

VII. Gas holder key and vent key: the functions of these two keys are interlocked. The vent key is set to one hour, the gas holder key is set to zero, and the output of No. 5 valve is disconnected (the chimney valve is opened, and the main coal valve is closed); The gas holder key is set to one hour, the vent key is set to zero, and the output of No. 5 valve is connected (the chimney valve is closed, and the main coal valve is open). This function can be used when the corresponding system is in the driving or parking state

VIII. Stop clean key: when the stop clean key is set to one hour, the output of No. 5 valve is disconnected (the chimney valve is opened, and the main coal valve is closed), and the blowing step time is added to the blowing step

IX. full up function: when the full up key is set to one hour, the down blowing step in this cycle is cancelled, and the down blowing step time is added to the up blowing step

X. return to zero function: return the queuing clock of the corresponding system to zero, make it count from zero, and the corresponding system starts to execute from the second up drive, and the delay and stepping functions are reset

Xi. Emergency stop: after the emergency stop key is set to one, all outputs of the corresponding system are disconnected, all functions are reset, and the start key is reset. The corresponding system recovers to the parking state before starting

XII. Start/stop key: when the corresponding system is in the stop state and the idle key is zero, click this key to set the start position and the air brake position as one, and the corresponding system starts up and executes the complete two-way operation before entering the cycle; When the corresponding system starts to execute the cycle, click this key to set the parking space as one, and the corresponding system cannot stop immediately at this time, but should stop after performing the blowing step for a period of time

XIII. After the execution of this step, turn off the output of this step and execute the next step. The next step can be executed normally only after the valve controlled by this step and the valve controlled by the next step are turned off, so as to prevent the valves controlled by the previous and next steps from being in the open state at the same time

XIV. The execution time of blowing up is calculated according to the actual execution time and total cycle time of the remaining five steps, which does not need to be set

XV. The blowing valve requires delayed closing, and the delay time is set by the operator

XVI. It is required to delay the opening of the upper valve, and close it before the completion of the upper blowing time

Copyright © 2011 JIN SHI