Functional safety design & SIL verification for large-scale ethanol storage
Process safety
Prohead Engineering understands both the process technology and the E&I engineering of safety functions. This results in HAZOP/LOPA projects that lead to the implementation of safety loops, all supported by our colleagues.
About the case
Context:
A large Belgian contract filler built a new plant with extensive production and storage capacity. A key part of this was a 500,000-litre ethanol storage installation, connected to piping systems, pumps and an unloading bay. Because ethanol is a flammable liquid, explosion safety (ATEX) was central.
Approach:
The initial request to Prohead Engineering was to guide the client through the ATEX process. To this end, a HAZOP and LOPA were first carried out to systematically map the possible scenarios. These analyses showed that additional measures were needed to control the risks sufficiently.
This led to the implementation of functional safety (in accordance with IEC 61511):
- identification of the Safety Instrumented Functions (SIFs),
- drafting of Safety Requirement Specifications (SRSs) for the ethanol storage and unloading bay,
- development of Cause & Effect diagrams for critical scenarios,
- SIL verification of the safety functions with detailed calculations,
- compilation of the SIS technical file as the final step of the project.
Result:
The combination of ATEX guidance, risk analyses and functional safety engineering delivered a fully demonstrable safety chain. The most critical safety functions were verified at SIL 2 level, and the client now has an audit-ready file that guarantees both legal compliance and business continuity.
Added value:
Thanks to this integrated approach, an initial ATEX question grew into a fully-fledged safety solution combining explosion safety, functional safety and operational reliability.