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Kevin McDonnell

Bio: Kevin McDonnell is an academic researcher from University College Dublin. The author has contributed to research in topics: Biomass & Renewable energy. The author has an hindex of 34, co-authored 153 publications receiving 4005 citations. Previous affiliations of Kevin McDonnell include Teagasc & National University of Ireland, Galway.


Papers
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TL;DR: In this paper, the performance of continuous carbon, Kevlar and glass fibre reinforced composites manufactured using the fused deposition modelling (FDM) additive manufacturing technique was evaluated both in tension and flexure.
Abstract: This study evaluates the performance of continuous carbon, Kevlar and glass fibre reinforced composites manufactured using the fused deposition modelling (FDM) additive manufacturing technique. The fibre reinforced nylon composites were fabricated using a Markforged Mark One 3D printing system. The mechanical performance of the composites was evaluated both in tension and flexure. The influence of fibre orientation, fibre type and volume fraction on mechanical properties were also investigated. The results were compared with that of both non-reinforced nylon control specimens, and known material property values from literature. It was demonstrated that of the fibres investigated, those fabricated using carbon fibre yielded the largest increase in mechanical strength per fibre volume. Its tensile strength values were up to 6.3 times higher than those obtained with the non-reinforced nylon polymer. As the carbon and glass fibre volume fraction increased so too did the level of air inclusion in the composite matrix, which impacted on mechanical performance. As a result, a maximum efficiency in tensile strength was observed in glass specimen as fibre content approached 22.5%, with higher fibre contents (up to 33%), yielding only minor increases in strength.

513 citations

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TL;DR: In this paper, the authors provide an update on recent laboratory research and commercial developments in fast pyrolysis and upgrading techniques, which is a relatively mature technology and is on the verge of commercialisation.
Abstract: Robust alternative technology choices are required in the paradigm shift from the current crude oil-reliant transport fuel platform to a sustainable, more flexible transport infrastructure. In this vein, fast pyrolysis of biomass and upgrading of the product is deemed to have potential as a technology solution. The objective of this review is to provide an update on recent laboratory research and commercial developments in fast pyrolysis and upgrading techniques. Fast pyrolysis is a relatively mature technology and is on the verge of commercialisation. While upgrading of bio-oils is currently confined to laboratory and pilot scale, an increased understanding of upgrading processes has been achieved in recent times.

438 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present an overview of the most suitable strains of microalgae for the purpose of carbon mitigation while the challenges associated with carbon mitigation strategies such as capital costs, environmental issues, and cultivation of micro-algae using flue gases will also be assessed.
Abstract: Climate change and rising atmospheric CO 2 levels have become much debated environmental issues in recent years. Point source emissions of CO 2 from industrialised processes such as power generation and cement production account for much of this increase. Direct carbon sequestration and storage techniques such as geological injection have large storage capacities, however these methods are very cost inefficient and have not been proved safe for long term sequestration. A novel approach to offsetting emissions is through direct biological carbon mitigation where CO 2 from the flue gases of point sources is used to cultivate photosynthetic autotrophic organisms. The produced biomass can subsequently be converted into biofuels, bio-chemicals, food or animal feed. These useful by-products provide revenue to finance the carbon mitigation process. Large-scale cultivation of biological media on site at a power generation plant means that substantial amounts of biomass could be readily available for co-firing in the plant, thus decreasing the demand for fossil fuels. This review gives an overview of the most suitable strains of microalgae for the purpose of carbon mitigation while the challenges associated with carbon mitigation strategies such as capital costs, environmental issues, and cultivation of microalgae using flue gases will also be assessed. Selected media will be required to have a high CO 2 fixing rate, a rapid growth rate, while being easily cultivated on a large scale in order to generate a large biomass yield and produce valuable by-products to offset the costs of carbon mitigation. An economic balance is also discussed to give an indication of the cost benefits in the implementation of biological carbon mitigation policies as a solution to the high capital and running costs of large scale microalgal production.

187 citations

Journal ArticleDOI
TL;DR: A review of current state-of-the-art commercial pyrolysis processes for the production of liquid transport fuels from waste polyolefins (polyethylenes and polypropylenes) is presented in this paper.
Abstract: With generation of waste plastics increasing, current EU legislation dictates high recovery rates and policy favours waste management technology choices that occupy a high position on the waste management hierarchy. Pyrolysis is a thermochemical conversion technology that can be considered a ‘feedstock recycling’ process and may play an increasing role in integrated waste management systems of the future. The objective of this article is to present a review of current state-of-the-art commercial pyrolysis processes for the production of liquid transport fuels from waste polyolefins (polyethylenes and polypropylenes). Current plastic waste generation and management practices are briefly summarised. Waste management infrastructure in Europe is reliant on landfill, incineration and mechanical recycling, while feedstock recycling plays an insignificant role. Plastic-to-liquid platforms including delocalised pyrolysis followed by centralised upgrading, stand alone facilities, and integrated waste management infrastructure concepts are briefly discussed. Commercial operations and their process configurations are compared. Reactor technology for cracking of plastic waste is presented. Important issues like fuel quality and contamination are also discussed. Fuel finishing operations and fuel additives required to achieve an engine ready fuel are described in the final section. Recently published laboratory research in thermal and catalytic pyrolysis and integrated and co-processing studies are also summarised in this review.

177 citations

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TL;DR: An overview of thermal imaging for food safety and quality assessment can be found in this paper, where the authors provide an overview of TI-theory, equipment, and image processing.
Abstract: Thermal imaging (TI) is an emerging, non-invasive process analytical technique suitable for the food industry. While TI was originally developed for military applications, it has recently emerged as a powerful non-destructive measurement technique in other industries. This paper provides an overview of TI theory, equipment, and image processing. Recent advances and potential applications of TI for food safety and quality assessment such as temperature validation, bruise and foreign body detection and grain quality evaluation are reviewed.

173 citations


Cited by
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01 Jan 1993

2,271 citations

Journal ArticleDOI
TL;DR: A broad review of the state-of-the-art biomass pyrolysis research can be found in this article, where three major components (cellulose, hemicellulose and lignin) are discussed in detail.

1,613 citations

Journal ArticleDOI
TL;DR: In this paper, a general summary of the properties of pyrolytic products and their analysis methods is given, as well as a review of the parameters that affect the process and a summary of current state of the art.
Abstract: Pyrolysis is one of the thermochemical technologies for converting biomass into energy and chemical products consisting of liquid bio-oil, solid biochar, and pyrolytic gas. Depending on the heating rate and residence time, biomass pyrolysis can be divided into three main categories slow (conventional), fast and flash pyrolysis mainly aiming at maximising either the bio-oil or biochar yields. Synthesis gas or hydrogen-rich gas can also be the target of biomass pyrolysis. Maximised gas rates can be achieved through the catalytic pyrolysis process, which is now increasingly being developed. Biomass pyrolysis generally follows a three-step mechanism comprising of dehydration, primary and secondary reactions. Dehydrogenation, depolymerisation, and fragmentation are the main competitive reactions during the primary decomposition of biomass. A number of parameters affect the biomass pyrolysis process, yields and properties of products. These include the biomass type, biomass pretreatment (physical, chemical, and biological), reaction atmosphere, temperature, heating rate and vapour residence time. This manuscript gives a general summary of the properties of the pyrolytic products and their analysis methods. Also provided are a review of the parameters that affect biomass pyrolysis and a summary of the state of industrial pyrolysis technologies.

1,379 citations