Inherently safer design of carbon-neutral methanol production

In the present framework of global energy transition, a significant increase in the use of carbon-neutral synthetic fuels as renewable energy carriers is expected in the next years. Renewable resources are huge even though scarcely exploitable due to aleatory availability and costs of transportation when produced in remote areas and offshore. Thus, the synergy of methanol production with oil & gas activities represents a beneficial opportunity to share infrastructures and convert renewable energy in a synthetic liquid fuel which can be easily stored and transported. Renewable methanol is a valuable chemical and an energy transition fuel with several applications, in particular in the mobility sector. Moreover, the use of carbon dioxide as raw material for the methanol synthesis could have a positive impact on the global carbon balance, valorising the attractive “Carbon Capture and Utilization (CCU)” concept. However, the novelty of renewable methanol process technologies in the renewable energy context requires a thorough investigation of the critical concerns of the possible routes, among which the safety challenges are prominent. The application of the inherent safety approach can play a paramount role for orienting choices in the preliminary design phases of safer methanol production processes. In the present study, reference schemes for processes proposed for renewable synthetic methanol production were defined. The expected inherent safety performance of the alternative processes were assessed by a specific system of multi-criteria key performance indicators (KPIs), based on the consequence simulation of potential accident scenarios affecting different targets (i.e. humans, assets, environment) both onshore and offshore. The results of the applied methodology allowed a preliminary screening of the hazard level of the alternative process routes, as well as the identification of the key safety issues that need to be addressed in the further development of inherently safer methanol production technologies.