As part of the development work on a chemical processing plant subject to Legislative Decree 105/2015 (Seveso III), the construction of a new energy recovery plant for aqueous streams containing flammable solvents in low concentrations (methanol, acetone, isopropanol and dimethylamine) required the establishment of a new fire zone equipped with fixed fire protection, in line with the active protection standards already adopted for the other process departments. TECSA developed, for the Client — a leading process chemicals company — the sizing and basic design of the new fixed water/foam fire-protection system to safeguard the equipment in the area, making the most of the plant’s existing infrastructure: the DN 8″ underground looped fire-fighting water mains, maintained at 7 bar by a pumping station with 650 m³/h diesel motor pumps and a water reserve of 1,200 m³, and the department’s foam premixers.
The design process ranged from the analysis of the process area and the substances present, through to the survey of the fire-fighting network and existing equipment, right up to the definition of the sizing criteria and the production of the technical drawings. The hydraulic sizing was carried out in accordance with best practice criteria for low-expansion foam systems (ref. NFPA 11, UNI EN 13565-2) and the plant’s technical standards, within the framework of Legislative Decree 105/2015 and Presidential Decree 151/2011.
The basic design was delivered with a complete set of drawings — a technical design report, plan extracts showing the location and routing of the pipework, a P&ID flow diagram of the compartment protection system, and a datasheet for the water/foam nozzle used for supply — which unambiguously defines the system for the contractor’s detailed design, for the joint hydraulic and functional testing, and for the formalisation of the ‘No Increase in Fire Risk’ Certificate and the SCIA, in support of the fire prevention obligations of the operator under the Seveso regulations.
