Derivative Control And Set Point Time Ramp Question

[hswang2]

First, I would like to introduce this process is ethylene oxide + nonyl phenol process (please see the detail reaction in attached file).The controller FIC-030 measures and controls the feed flow of the nonyl phenol by FE/FIT-030A/B and the control valve FV-030 . The selector FHS-030 is used to select the FE/FIT-030 A/B used by controller FIC-030.The totalizers, FQI-030A/B, are used to totalize the nonyl phenol flow rate. The selector FY-030B uses the greatest value among FQI-030A/B to avoid overdosing. The pressure set-point time ramp is stored in PY-001D (set point generator). It acts on the set-point of PIC-001D in cascade mode as shown in following example. (pls see attached file)

Besides that, Safety interlock (S-001, S-004) is Shutdown EO by following event detected, and interlock(I-010) also stop EO injection by following event detected

Event 1 : PDHH-001D actuated (PIC-001D automatic mode (reactor pressure controller)
and Absolute value (SP-PV) > 1 bar)
Event 2 : Variation PIT-001 A/B/C 2oo3.PV in 50 miliseconds > 1 bar


N1. What is the set-point time ramp and set point generator means?
N2. Question S-1 square side dp/dt means Event 2 condtion? And what is relation with
Derivative control?

 

[Chance17]

First of all, I confuss that I do not completely understand the information furnished. But it looks to me

N1. There is some function generator that periodically calculates a new flow setpoint.

N2. This has nothing to do with derivative control. The flow control calculation is responding to runaway reaction.