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The results of the offshore integration of fossil and renewable energy sources (RESs) to produce an energy vector, namely methanol, are discussed. The methodology developed and hereby presented, allowed at first the selection of the best technology for offshore RESs exploitation, where a near-to-decommissioning platform is used as an energy hub. Based on the availability of natural gas from the depleted reservoir, the most suitable process for offshore methanol production was chosen among various alternative innovative processes. The optimal mix for energy production was then identified by varying the number of converters for each RES. Finally, the methanol production process was designed on the basis of the available electric power, including a backup system based on natural gas, to perform RESs valley filling and to achieve a steady state process.

In the framework of energy transition, safety is a key requirement to be satisfied by novel process technologies. The aim of this study is to compare, from an inherent safety standpoint, three technologies for the production of green hydrogen via water splitting, powered by Renewable Energy Sources (RESs), in order to identify the inherently safest option and the critical equipment and/or operating conditions to be considered in the scale-up and industrialization of such technologies. The technologies considered for green hydrogen production are: alkaline electrolysis, proton exchange membrane electrolysis and reversible Solid Oxide Cells. The application of a consolidated methodology for inherent safety assessment based on Inherent Safety Key Performance Indicators (IS-KPIs) enabled to identify the most critical units within each process scheme and to select the inherently safest technological solution presently available for green hydrogen production.

The release of hazardous materials induced by natural events affecting industrial facilities presents peculiar characteristics because of the huge potential extension of the affected areas. The reduction of both the likelihood and the magnitude of such events represents an essential step to reduce the risk associated with Natech accidents. Nevertheless, the evaluation of damage to the environment in Natech events has been poorly addressed. In the present study, past accidents analysis was carried out, using both a detailed description of specific accidents and an extended database of Natech events. Lessons learnt as well as possible common patterns and main features related to such accidents were identified and discussed. The results of the present study can be intended as a preliminary step for the development of models for the quantitative assessment of damage to the environment in major accidents caused by natural events.

Mathematical modelling of transient states of continuous stirred tank reactors was considered for the case of homogeneous liquid-phase reactions. A simple and very precise kinetic measurement strategy was proposed: registration of the reactor temperature during the start-up of the reaction process. The dynamic reactor model consisted of mass and energy balances written in dimensionless forms to enable general conclusions and easy computer implementation. Model simulations were carried out by using a numerical solver for stiff differential equations and a reaction invariant was revealed by theoretical analysis. A series of transient laboratory-scale experiments for a strongly exothermic reaction, a reaction between sodium thiosulphate and hydrogen peroxide was conducted and the kinetic parameters, the pre-exponential factors and activation energies were estimated. The data fitting was further improved by incorporating the decomposition of hydrogen peroxide as a side reaction. The estimated kinetic parameters were investigated further by sensitivity analysis and Markov-Chain-Monte-Carlo-Method (MCMC) to confirm their reliability. The proposed method is applicable for relatively simple systems with a measurable heat effect. For complex multireaction systems the method should be completed with chemical analysis.

In the recent years, the biogas industry is rapidly growing, but the sector has been affected by several major accidents related to its supply chain, which pointed out the need to perform a detailed process safety analysis. Hazards and operability analysis (HazOp) is one of the most used and efficient technique for the identification of potential accidents, but its main limitation is the qualitative nature of the results. This study aims to override this limitation by supporting HazOp study using a dynamic simulator, which is able to reproduce deviations and operational failures in a typical biogas production plant, in order to help in the quantification of HazOp results and to improve safety and reliability of the process. The main result of the study is the maximum biogas production rate that can be safely handled by the system under normal conditions and then the maximum rate that can be allowed if some safety barrier (though correctly designed) should fail has been evaluated too. The most critical failure identified is a malfunctioning in the pressure relief system of the digester, because under this condition, the maximum biogas production rate that can be reached is about 2/3 of the corresponding value for a properly working system.

In the present paper, a methodology for the self-assessment of health and safety management of a company was applied to biogas industry. The goal of this study was to depict a synthetic evaluation of the existing management system through the quantification of different key elements. Among them, the most interesting ones for the case under analysis were those related to (i) the attitude to risk reduction and people protection in compliance with the law, and (ii) the involvement, education and training of the personnel. The results obtained were compared with a previous application to a different sector with the aim of verifying the possible lack of safety management system, safety climate and risk perception in biogas industry.

In the present paper, a methodology for the determination of inherent safety distances for escalation and layout optimization has been introduced. A survey of past domino accidents triggered by thermal explosions have been carried out and analysed with the aim of a deeper understanding of the possible primary scenarios and related escalation vectors.

The present work focuses on process safety related to bioprocess engineering, meant as the integration between chemical engineering and biotechnology. A specific checklist has been created in order to perform a first step in bioprocesses hazard identification aimed at meeting not only personnel safety issues, but also process safety ones. The bioprocess of biogas production from anaerobic digestion of livestock slurry was taken as a case study to show the methodology.

A method for dynamic risk assessment of thermal hazards due to runaway reactions is described by means of a tutorial and implemented to study the thermal decomposition of an organic peroxide. The analysis is based on an adiabatic experiment, providing data that can closely predict large-scale behavior. The experimental equipment used allows online monitoring of the temperature and rate of temperature of the hazardous material subject to runaway reaction safety. The calculation of thermal risk index is dynamically performed, and the risk obtained is compared to a predefined risk scale. On the basis of the risk ranking, adequate preventative and protective measures can be implemented

Many industrial accidents in the recent past showed that the thermal decomposition of Cumene Hydroperoxide (CHP) can lead to runaway reactions and subsequent fires and explosions. Still this organic peroxide is extensively used in the petrochemical industry. This paper is aimed at a better understanding of the possible consequences of CHP decomposition by analyzing its thermal behaviour when dissolved in a high boiling point solvent using two different adiabatic calorimeters. The experimental data obtained allowed us to assess the general trends on the main runaway parameters and to characterized the thermal decomposition of the mixture with respect to the peroxide concentration, as well as the influence of the thermal inertia of the equipment. The gas generation rate for each of experiment was calculated and then corrected to adiabatic conditions. The data generated can assist as a guidance for designing processes where CHP is involved, along with their safeguards.