D-FNN Based Modeling and BP Neural Network Decoupling Control of PVC Stripping Process

Table 1

Parameters of PVC string tower.

Parameter	Scope	Alarm value	Normal scope	Real value
Temperature in tower top	0–150°C	Upper limit: 110°C; Lower limit: 70°C	80–105°C	85°C
Temperature in tower bottom	0–150°C	Upper limit: 130°C; Lower limit: 100°C	105–113°C	107°C
Pressure in tower top	0-0.1 MPa	Upper limit: 0.08 MPa; Lower limit: 0.02 MPa	0.03–0.06 MPa	0.03 MPa
Pressure difference in tower	0–60 MPa	Upper limit: 30 MPa; Lower limit: 5 MPa	10–25 MPa	15 MPa
Steam flow rate	0–4000 kg/h	Upper limit: 3500 kg/h; Lower limit: 1000 kg/h	1500–3000 kg/h	2200 kg/h
Inlet slurry flow rate	0–80 m^3/h	Upper limit: 70 m^3/h; Lower limit: 15 m^3/h	35–50 m^3/h	40–45 m^3/h
Steam pressure in tower	0–0.6 MPa	Upper limit: 0.5 MPa; Lower limit: 0.15 MPa	0.35–0.4 MPa	0.38 MPa