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Climate change is a global phenomenon that has become a focus of concern for society, mainly due to its impacts on daily lives. Despite being a global issue that affects the entire planet, these effects are not felt in the same way in all regions, so the analysis of processes from a regional or local perspective allows a better adaptation of populations to the new reality, as well as being used as a supporting tool for decision making when implementing mitigation measures. For the present analysis, a region in Northern Portugal was chosen, which is in the Mediterranean region, considered one of the hot spots for climate change. In this region of Entre Douro e Minho, more specifically in the municipality of Guimarães, the climate of the last centuries was reconstructed based on documentary information and recent data collected and modeled for the region under study. The results show a successive alternation of hot and dry periods with colder and wetter ones, where climate instability seems to be the dominant trend over the last thousand years. Currently, with the advent of a new period of climatic instability, which, unlike the periods verified previously, now have an anthropic origin, there is a tendency for a new period to occur, in which conditions will tend to be hotter and drier. Knowing this trend in advance allows informed decisions to be made to mitigate some problems that can be associated with these conditions, such as the increase in the risk of wildfires, the proliferation of invasive species, the decrease in agriculture and forests productivity, or even the occurrence of extreme weather events. [ABSTRACT FROM AUTHOR]

The search for different forms of biomass that can be used as an alternative to those more traditional ones has faced numerous difficulties, namely those related to disadvantages that the majority of residual forms present. However, these residual forms of biomass also have advantages, namely the fact that, by being outside the usual biomass supply chains for energy, they are usually much cheaper, and therefore contribute to a significant reduction in production costs. To improve the less-favorable properties of these biomasses, thermochemical conversion technologies, namely torrefaction, are presented as a way to improve the combustibility of these materials. However, it is a technology that has not yet demonstrated its full potential, mainly due to difficulties in the process of scale-up and process control. In this article it is intended to present the experience obtained over 5 years in the operation of a biomass torrefaction plant with an industrial pilot scale, where all the difficulties encountered and how they were corrected are presented, until it became a fully operational plant. This article, in which a real case study is analyzed, presents in a descriptive way all the work done during the time from when the plant started up and during the commissioning period until the state of continuous operation had been reached. [ABSTRACT FROM AUTHOR]

Coal–water slurry or coal–water mixture (CWS or CWM) is a complex solid–liquid dispersion. Several research works have been done concerning the production and use of CWSs being developed worldwide in several different governmental, industrial and academic facilities. In the present paper, studies on the developments achieved in the past three decades with regard to the field mentioned above are systematically reviewed, with particular regard to several different aspects during the combustion process. The structure and properties of the coal are highlighted, as are the different additives used and their adaptability with different types of coal, where the particle size distributions are of great importance in determining both the slurryability of coal and the rheological behavior of a produced CWS for its intended characteristics. At a time when there is much debate about the end of the age of coal as a primary source of thermal and electrical energy, alternative forms of use that can contribute to the reduction of pollutant emissions, as well as particles, in the atmosphere offer alternatives that may allow us to continue using coal, at least during this transition period until a viable alternative is found. In-depth knowledge of these coal slurries may allow, in the future, the development of similar products produced from fuels derived from biomass, such as charcoal or torrefied biomass. [ABSTRACT FROM AUTHOR]

The biomass industry is growing due to the current search for greener and more sustainable alternatives to fossil energy sources. However, this industry, due to its singularity, presents several challenges and disadvantages related to the transportation of raw materials, with the large volumes that are usually involved. This project aimed to address this internal logistics situation in torrefied biomass pellets production with two different biomass storage parks, located in Portugal. The main park receives raw material coming directly from the source and stores it in large amounts as a backup and strategic storage park. The second park, with smaller dimensions, precedes the production unit and must be stocked daily. Therefore, a fleet of transport units with self-unloading cranes is required to help to unload the biomass at the main park and transport the raw material from this park to the one preceding the production unit. Thus, the main goal was to determine the dimensions of the fleet used in internal transportation operations to minimize the idle time of the transport units using a methodology already in use in the mining and quarrying industry. This methodology was analyzed and adapted to the situation presented here. The implementation of this study allows the elimination of unnecessary costs in an industry where the profit margins are low. [ABSTRACT FROM AUTHOR]

Today, climate change is assumed by many researchers and scholars as a certainty and is presented as the biggest challenge humanity has ever faced. It is commonly accepted that anthropogenic greenhouse gas emissions are the main cause that is accelerating the process. Therefore, it is urgent to find solutions to mitigate climate change, mainly because the intense effects have already been felt, in many cases in the form of the occurrence of extremely violent weather events. Forests are undoubtedly one of the most effective and easiest ways to provide the function of carbon sinks. However, it is essential and convenient to analyze the permanence time of this carbon in forests, because this permanence time depends directly on the forest management model used. This article aims to analyze forest management models from the perspective of carbon residence time in temperate forests, dividing the models into three types, namely carbon conservation models, carbon storage models, and carbon substitution models, according to their ability to contribute to functioning as carbon sinks, thereby contributing to the mitigation of climate change. [ABSTRACT FROM AUTHOR]

With climate change being a certainty, which today is probably the biggest challenge humanity is facing, and also accepting that greenhouse gas emissions are the main cause accelerating climate change, there is an urgent need to find solutions that lead to the mitigation of the already intense, and in some cases, even violent, effects. Forests can most easily work as carbon sinks. However, it is convenient to analyze the residence time of this carbon in forests, as this residence time will depend on the type of forest management used. This paper aims to analyze forest management models from a perspective of carbon residence time in forests, dividing the models into three types: carbon conservation, carbon storage, and carbon substitution. Carbon conservation models are those models in which the amounts of carbon stored only replace the carbon released, mainly by the industrial use of raw materials. Carbon storage models are models that foster the growth of forest areas to ensure that the amount of carbon stored grows, and where the ratio clearly leans towards sequestration and storage. Carbon substitution models are models that move towards the substitution of fossil carbon by renewable carbon, thus contributing to the creation of a neutral flow. [ABSTRACT FROM AUTHOR]