Grupo Miesa has developed a complete automation, control and safety solution for a liquefied petroleum gas (LPG) storage terminal and its filling plant, two independent facilities at different locations in the Caribbean. The system is still in operation today and stands out for its functional complexity and for integrating several systems under the Siemens PCS 7 architecture.
- 2independent PCS 7 systems, one per facility
- 200 m³pressurised LPG bullets
- 1,25010 kg cylinders per hour at the filling plant
- 18causes in the terminal’s safety matrix
Project scope
- Automation of LPG emptying, filling, transfer and storage in 200 m³ pressurised bullets
- Control of loading and unloading from ships, road tankers or the refinery itself
- Supervision of the mercaptan tank for gas odorisation
- Management of the filling plant, with a capacity of 1,250 10 kg cylinders per hour
- Process instrumentation for pressure, temperature, flow, level and digital signals
- Emergency Shutdown System (ESD) with fire, earthquake and storm signals
Instrumentation installed
Terminal
- 26 solenoid valves
- 2 mass flowmeters
- 18 LPG gas sensors
- 12 flame sensors
- 4 high and low level sensors on the bullets
- 5 pressure transmitters
- 4 temperature transmitters
- Dräger panel for fire and gas (F&G) integration
Filling plant
- 22 solenoid valves
- 2 mass flowmeters
- 18 LPG gas sensors
- 14 flame sensors
- 9 pressure transmitters
- 4 temperature transmitters
- 1 storm sensor
- 1 earthquake sensor
All transmitters work with 4-20 mA + HART and are configured with Siemens SIMATIC PDM, without fieldbuses. Some existing instruments were kept at both facilities; the critical instrumentation was supplied by Miesa.
Control technology and architecture
- Two independent PCS 7 systems, one per facility, with engineering, operator and safety stations
- Local or back-up operator desk at each facility, for immediate control from the plant in a contingency
- Control logic, automatic sequences and distributed alarms
- Safety matrix with 18 causes at the terminal
- ATEX area classification provided by the customer and applied throughout the engineering
- Project executed in accordance with SIL 2/3 (IEC 61511)
- Redundancy in servers, stations, buses and controllers
Complementary systems
- CCTV with ATEX cameras and cameras in industrial areas, integrated in PCS 7
- Fire protection system with a Dräger REGARD panel and gas and flame sensors communicating with the control system
- Access control with biometrics, number plate recognition, automatic gates and turnstiles
- Visitor and staff management from the centralised infrastructure
A complete solution
Miesa handled the project from start to finish: basic and detailed engineering, design and programming of the PCS 7 system, selection and integration of instrumentation in ATEX zones, installation supervision, commissioning and functional validation in the field. The result is centralised, real-time supervision of both sites.