Biorefinery Safety: A Case Study Focused on Bioethanol Production

With reference to the framework for energy and climate, the European Union (EU) has stated that at least a 32% share of renewable energy consumption has to be achieved within 2030. This context generates attention to the potential hazards, which are associated with flammable biofuels, such as the bioethanol. One of the main hazards, referred to such biofuel, is the formation of potentially explosive atmospheres due to its evaporation from pools in case of accidental releases. In fact, in a bioethanol production plant (biorefinery), there are several components (flanges, valves, pumps, etc.), which can become potential emission sources in case of failure. Bioethanol is a high-boiling liquid, because its boiling temperature (Tboiling = 78°C) is higher than ambient temperature. Therefore, in case of release and spreading on a certain medium, evaporation occurs because of vapor diffusion. The chapter is focused on a case study. In particular, the chapter illustrates a comparison between two predictive models aimed at estimating the bioethanol evaporation rate, which is a fundamental parameter for determining the dilution degree and classifying the workplaces, where potentially explosive atmospheres could occur. The study investigates the influence of bioethanol release temperature and therefore of its vapor pressure on evaporation rate

Biogas Production Plants: A Methodological Approach for Occupational Health and Safety Improvement

Existing lessons on public safety, referred to as new biotech plants, suggest that the development of effective, responsive and responsible safety standard can improve the trust of the public in the new generation plants such as biorefineries. This implies the need for specific risk assessment aimed at defining the mitigation measures, which can minimize the impact of hazards on workers’ health. The main hazards, referred to biogas production process, are biohazard, fires and potentially explosive atmospheres. In particular, the last two hazards strictly depend on the presence of methane in the biofuel. This chapter presents the results of a work aimed at providing the biogas industry with a practical tool, which can be used to carry out the analysis of hazards of biogas plants. The adopted method for developing the tool is based on the well-known checklist approach. The checklist is a valuable support for the plant operator to evaluate periodically the actual effectiveness of the overall safety measures and ensure a safer management of the biogas plant. The checklist can meet these requirements. This chapter reports the main preventive, protective and managerial measures, which can be adopted to decrease the hazardous outcomes on workers’ health and safety

From soil remediation to biofuel. Process simulation of bioethanol production from Arundo donax

A range of energy crops can be grown on marginal land (i.e. land that is not suitable for food crop production or contaminated site) to provide feedstocks for bioenergy, non-food products and biofuels. The food versus fuel debate had a significant negative impact in Europe on first generation biofuels production from food crops (i.e. wheat, rapeseed, etc). A new approach involving the use of marginal land for the production of lignocellulosic species for the production of bioethanol is now pursued in Italy and in many other countries, where the demand for high quality water resources, arable land, food and fossil fuels is rapidly growing. With an emerging “feed versus fuel debate” there is a pressing need to find options for the use of marginal lands and wastewaters or saline ground waters to produce second generation biofuel or bio paper crops. Arundo donax was selected as a potential crop for use in these areas, since it produces more cellulosic biomass and sequesters more contaminants, using less land and pesticides than any other alternative crops reported in the literature. The objective of this paper is to evaluate economically a simplified process for the production of second generation bioethanol from A. donax. Process calculations and economic analyses are performed using the software SuperPro Designer®

Biomethane Compression Unit: a Methodological Approach Aimed at Decreasing the Atex Zones Hazardousness

The smart combination of renewable energy sources will be fundamental for developing the energy systems of the future and achieving carbon-neutrality by 2050. Biomethane, produced by biogas upgrading, is a renewable alternative to natural gas and it is able to decrease the greenhouse gas (GHG) emissions in multiple sectors. Indeed, this gaseous biofuel can be used in applications such as heating, transport and electric energy generation, since it has the same properties as natural gas. It can be directly injected into the existing gas network as a low-carbon alternative to natural gas. The strategic biomethane role determines a particular attention to potential hazards associated with its production. In particular, one of the main hazards is the possible formation of potentially explosive atmospheres due to accidental releases from components, such as valves, compressors, flanges, etc. The biomethane compression is the most hazardous phase of its production process, because it occurs in an indoor place (compression unit) and it is characterized by the highest pressure values. The paper is focused on biomethane compression unit and it illustrates a methodological approach aimed at decreasing the Atex zones hazardousness

Occupational Health Issue in a 2G Bioethanol Production Plant

The interest of scientists and health authorities in occupational risk related to biofuels production has recently increased due to the development of agro-industrial waste recycling processes in the framework of the European circular economy strategy and energy production from renewable sources. A common biofuel is the bioethanol, which is a leading candidate to substitute the gasoline as a transport fuel and it can be produced via biomass fermentation process. In biofuels production plants, some work activities in processing of biomass, are sources of airborne dust and the employers should demonstrate that adequate control measures have been implemented in order to prevent workers exposure. In the chapter, the production process of a 2G bioethanol plant has been analyzed in order to specify the process phases, which could generate occupational health issue related to airborne dust, and to provide technical recommendations

How Can AI be Distributed in the Computing Continuum? Introducing the Neural Pub/Sub Paradigm

This paper proposes the neural publish/subscribe paradigm, a novel approach to orchestrating AI workflows in large-scale distributed AI systems in the computing continuum. Traditional centralized broker methodologies are increasingly struggling with managing the data surge resulting from the proliferation of 5G systems, connected devices, and ultra-reliable applications. Moreover, the advent of AI-powered applications, particularly those leveraging advanced neural network architectures, necessitates a new approach to orchestrate and schedule AI processes within the computing continuum. In response, the neural pub/sub paradigm aims to overcome these limitations by efficiently managing training, fine-tuning and inference workflows, improving distributed computation, facilitating dynamic resource allocation, and enhancing system resilience across the computing continuum. We explore this new paradigm through various design patterns, use cases, and discuss open research questions for further exploration

Recirculation factor as a key parameter in continuous-flow biomass selection for polyhydroxyalkanoates production

The effectiveness of polyhydroxyalkanoates (PHA) production with mixed microbial cultures (MMC) largely depends on the selection of PHA-storing microorganisms, conventionally performed in sequencing batch reactors (SBR). These, although easily allow the establishment of the required feast and famine (FF) regime, can represent a factor of cost increase when the process is scaled up. Here, a novel continuous-flow process for MMC selection under FF conditions has been developed by using two sequentially operated reactors. The feast reactor, having a tubular configuration, was continuously fed with a synthetic mixture of acetic and propionic acids (at an organic loading rate of 2.12 gCOD/L d) and the effluent of this reactor was in part sent to the CSTR famine reactor. The recirculation factor (RC), that is the ratio between the recirculation flow rate and the feeding flow rate to the feast reactor, was the main parameter investigated. Four different runs were performed with the RC varying from 1 to 8 and the increase in its value caused a decrease of the biomass residence time in each reactor. The intracellular PHA content in the feast reactor almost linearly increased up to RC 4 (with a value of 34 ± 2 %, wt/wt) and dropped at the RC 8 condition that, however, showed the maximum PHA content (58 ± 5 %, wt/wt) during the accumulation tests. Indeed, the relative abundance of sequences affiliated with putative PHA-storing bacteria increased up to 90.5 % at RC 8 and were dominated by members of the Alphaproteobacteria class mostly represented by the genus Meganema (74 %)

Imaging Modalities for the Diagnosis of Vascular Graft Infections:A Consensus Paper amongst Different Specialists

Vascular graft infection (VGI) is a rare but severe complication of vascular surgery that is associated with a bad prognosis and high mortality rate. An accurate and prompt identification of the infection and its extent is crucial for the correct management of the patient. However, standardized diagnostic algorithms and a univocal consensus on the best strategy to reach a diagnosis still do not exist. This review aims to summarize different radiological and Nuclear Medicine (NM) modalities commonly adopted for the imaging of VGI. Moreover, we attempt to provide evidence-based answers to several practical questions raised by clinicians and surgeons when they approach imaging in order to plan the most appropriate radiological or NM examination for their patients

National Trends in Main Causes of Hospitalization : A Multi-Cohort Register Study of the Finnish Working-Age Population, 1976-2010

Peer reviewe

Imaging Modalities for the Diagnosis of Vascular Graft Infections: A Consensus Paper amongst Different Specialists

Vascular graft infection (VGI) is a rare but severe complication of vascular surgery that is associated with a bad prognosis and high mortality rate. An accurate and prompt identification of the infection and its extent is crucial for the correct management of the patient. However, standardized diagnostic algorithms and a univocal consensus on the best strategy to reach a diagnosis still do not exist. This review aims to summarize different radiological and Nuclear Medicine (NM) modalities commonly adopted for the imaging of VGI. Moreover, we attempt to provide evidence-based answers to several practical questions raised by clinicians and surgeons when they approach imaging in order to plan the most appropriate radiological or NM examination for their patients