The process of torrefaction alters the physical properties of biomass, reducing its fibrous tenacious nature. This could allow increased rates of co-milling and therefore co-firing in coal fired power stations, which in turn would enable a reduction in the amount of coal used and an increase in the use of sustainable fuels, without the need for additional plant. This paper presents an experimental investigation of the pulverisation behaviour of two torrefied energy crops, namely: willow and Miscanthus. A multifactorial method approach was adopted to investigate the three process parameters of temperature, residence time and particle size, producing fuels treated using four different torrefaction conditions. The untreated and torrefied fuels were subjected to standard fuel analysis techniques including ultimate analysis, proximate analysis and calorific value determination. The grindability of these fuels was then determined using a laboratory ball mill and by adapting the Hardgrove Grindability Index (HGI) test for hard coals. After grinding, two sets of results were obtained. Firstly a determination similar to the HGI test was made, measuring the proportion of sample passing through a 75 µm sieve and plotting this on a calibrated HGI chart determined using four standard reference coals of known HGI values. Secondly the particle size distributions of the entire ground sample were measured and compared with the four standard reference coals. The standard fuel tests revealed that temperature was the most significant parameter in terms of mass loss, changes in elemental composition and energy content increase. The first grindability test results found that the untreated fuels and fuels treated at low temperatures showed very poor grindability behaviour. However, more severe torrefaction conditions caused the fuels to exhibit similar pulverisation properties as coals with low HGI values. Miscanthus was found to have a higher HGI value than willow. On examining the particle size distributions it was found that the particle size distributions of torrefied Miscanthus differed significantly from the untreated biomass and had comparable profiles to those of the standard reference coals with which they had similar HGI values. However, only the torrefied willow produced at the most severe conditions investigated exhibited this behaviour, and the HGI of torrefied willow was not generally a reliable indicator of grindability performance for this energy crop. Overall it was concluded that torrefied biomass can be successfully pulverised and that torrefied Miscanthus was easier to grind than torrefied willow.

Biomass is an especially reactive fuel. There have been large increases in the transportation and utilization of biomass fuels over the past 10 years and this has raised concerns over its safe handling and utilization. Fires, and sometimes explosions, are a risk during all stages of fuel production as well as during the handling and utilization of the product. This paper presents a method for assessing ignition risk and provides a ranking of relative risk of ignition of biomass fuels. Tests involved single particle measurements, thermal analysis, dust layer and basket ignition tests. In all cases, smouldering combustion was observed, whereby the fuels pyrolyse to produce a black char, which then subsequently ignites. Low temperature pyrolysis kinetics have been utilised to predict ignition delay times at low temperatures. A method for evaluating risk was explored based on the activation energy for pyrolysis and a characteristic temperature from {TGA} analysis. Here, olive cake, sunflower husk and Miscanthus fall into the high risk category, while the woods, plane, pine, mesquite and red berry juniper, fall into the medium risk category. This method is able to capture the impact of low activation energy for pyrolysis on the increased risk of ignition

Agricultural practices are at a significant cross roads: continuous population growth, increasing evidence of food shortage and reduced land availability are just a few of the problems highlighting the need to improve existing agricultural methods. Moreover, recurrent emerging episodes of catastrophic natural phenomena occurring across the world, such as global warming, increased natural disasters and depletion of natural resources are pushing the bar even higher, in terms of the urgent need to find viable solutions to tackle food security. The research community is under pressure to find solutions towards the above issues in tandem with the protection of the natural environment and the need to improve quality of life. In parallel, the architectural challenges are outlined by the same realities, because cities will continue to grow and it is imperative to find solutions to minimise the impact of urban development on the planet. Two key areas have been identified in this research, they are considered to have the potential to simultaneously help to mitigate the problems mentioned above: 1) Improved design of buildings and cities to encourage urban biodiversity, i.e. better urban design and architectural practices. 2) Enhanced methods to produce, store and distribute food, i.e. improved rural and urban agriculture: produce, storage and distribution. Scrutiny into these topics lead this investigation into vertical farming and the exploration on how it can be improved. A simulation methodology is under development, aiming to reproduce the potential capabilities of vertical farms, exploring their wider viability and their integration into existing and new buildings. This paper follows the development of this methodology, its current capabilities and the future directions of this ongoing investigation.

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In order to inform the design of a building or a group of buildings in relation to their potential energy efficiency, the main impact will be at the initial concept design stage. Variations and interactions of parameters need to be considered quickly as the design develops. In addition to the variation and interrelation of parameters associated with individual buildings, the design should consider the influence, both from and on, neighbouring buildings and landscape features. This paper describes the development of two modelling processes, based around the established building energy model, HTB2, and the urban scale energy model EEP. Example case studies from China are given to illustrate the processes.