Maurizio Volpe

Bio: Maurizio Volpe is an academic researcher from University of Trento. The author has contributed to research in topics: Hydrothermal carbonization & Char. The author has an hindex of 21, co-authored 49 publications receiving 1239 citations. Previous affiliations of Maurizio Volpe include University of Palermo & University of California, Santa Barbara.

Hydrothermal Carbonization as a Valuable Tool for Energy and Environmental Applications: A Review

Abstract: Hydrothermal carbonization (HTC) represents an efficient and valuable pre-treatment technology to convert waste biomass into highly dense carbonaceous materials that could be used in a wide range of applications between energy, environment, soil improvement and nutrients recovery fields. HTC converts residual organic materials into a solid high energy dense material (hydrochar) and a liquid residue where the most volatile and oxygenated compounds (mainly furans and organic acids) concentrate during reaction. Pristine hydrochar is mainly used for direct combustion, to generate heat or electricity, but highly porous carbonaceous media for energy storage or for adsorption of pollutants applications can be also obtained through a further activation stage. HTC process can be used to enhance recovery of nutrients as nitrogen and phosphorous in particular and can be used as soil conditioner, to favor plant growth and mitigate desertification of soils. The present review proposes an outlook of the several possible applications of hydrochar produced from any sort of waste biomass sources. For each of the applications proposed, the main operative parameters that mostly affect the hydrochar properties and characteristics are highlighted, in order to match the needs for the specific application.

Recent advances in the development of biomass gasification technology: A comprehensive review

Abstract: Due to fast climate change and foreseen damage through global warming, access to clean and green energy has become very much essential for the sustainable development of the society, globally. Biomass based energy is one of the important renewable energy resources to meet the day to day energy requirements and is as old as the human civilization. Biomass gasification is among few important aspects of bioenergy for producing heat, power and biofuels for useful applications. Despite, the availability of vast literature, technological and material advancements, the dissemination of gasification technology could not overcome the critical barriers for the widespread acceptability over the conventional energy resources. This article presents a comprehensive review on the technical advancements, developments of biomass gasification technology and the barriers being faced by different stakeholders in the wide dissemination of the technology for day to day requirements of the society, followed by recommendations for policy makers to make this technology popular while serving the society.

Hydrothermal carbonization of renewable waste biomass for solid biofuel production: A discussion on process mechanism, the influence of process parameters, environmental performance and fuel properties of hydrochar

Abstract: The energy demand of the world is expected to reach 739 quadrillions BTU in 2040, which therefore demand for exploring more alternative source of renewable energy. Waste biomass though vast in reserve for generating renewable energy has its own downside. High moisture, fibrous nature, high bulk volume, hydrophilic nature and low calorific value are some of the inferior quality of waste biomass which creates bottleneck for easy renewable energy generation. Pre-treatment of biomass to overcome these challenges has created a new research interest. Among the treatment options available, the hydrothermal carbonization (HTC) method, which can process wet waste has become the most preferred choice among researchers recently. The HTC eliminates energy-intensive pre-drying process needed for other treatment methods such as pyrolysis, dry torrefaction and incineration. Through this article, we attempt to provide a detailed review of how renewable biomass can be effectively used to produce renewable energy by improving their inherent inferior characteristics. The review also highlights bottlenecks that constrain the deployment of renewable energy using HTC methods. The scope of further research direction is well identified in this review. The paper also present recent advancements which are filling the knowledge gap of HTC technology that were there earlier. Critical analysis of microwave assisted HTC and conventional heated HTC is also presented in this review. The analysis in this paper reveals that biomass is a valuable resource, and should be explored to take advantage of its renewable energy generation potential. The HTC method of biomass upgradation improves transport, storage and fuel characteristics by improving grindability, pellets durability, hydrophobicity, energy density, combustion behaviour and calorific value, and also helps in improving the environmental performance of solid fuel produced. Despite the fact that the technology is in the early stage of development and there still exist knowledge gap and shortcomings, the vast literature reviewed suggests that it has a potential of being future technology. Therefore, it needs further investigation which should fill existing shortcoming of the technology.

Innovative “Green” and Novel Strategies for the Extraction of Bioactive Added Value Compounds from Citrus Wastes—A Review

Abstract: Citrus is a major processed crop that results in large quantities of wastes and by-products rich in various bioactive compounds such as pectins, water soluble and insoluble antioxidants and essential oils. While some of those wastes are currently valorised by various technologies (yet most are discarded or used for feed), effective, non-toxic and profitable extraction strategies could further significantly promote the valorisation and provide both increased profits and high quality bioactives. The present review will describe and summarize the latest works concerning novel and greener methods for valorisation of citrus by-products. The outcomes and effectiveness of those technologies such as microwaves, ultrasound, pulsed electric fields and high pressure is compared both to conventional valorisation technologies and between the novel technologies themselves in order to highlight the advantages and potential scalability of these so-called “enabling technologies”. In many cases the reported novel technologies can enable a valorisation extraction process that is “greener” compared to the conventional technique due to a lower energy consumption and reduced utilization of toxic solvents.