Technical and environmental assessment of coated urea production with a natural polymeric suspension in spouted bed to reduce nitrogen losses

Urea is the most used nitrogen fertilizer in the world, but should be supplied to the plants in a controlled way to make it as efficient as possible. Otherwise, nitrogen losses due to volatilization and leaching can reach up to 70%. The production of coated urea with slow-release polymers can be a good alternative not just to reduce the nitrogen losses but also to avoid the greenhouse gases emissions related to the high consumption of this fertilizer. Therefore, the aim of this study is to evaluate the technical and environmental aspects of coated urea production in a spouted bed to control the nitrogen volatilization. The influence of the operating conditions in the coating performance was evaluated using a central composite rotational design and the environmental performance was determined using a life cycle assessment. The coating performance results showed that coated urea particle growth ranged from 0.8 to 4.4%, the coating efficiency presented results between 17 and 47% and the nitrogen volatilization reduction was significant (11–50%). The highest nitrogen volatilization reduction was obtained for suspension flow rate equal to 15 mL/min and air temperature equal to 85 °C. The daily volatilized nitrogen release profile and the microscopic analysis showed that the coating film was effective in controlling nitrogen release contained within the particle. The environmental analyses demonstrated that coated urea had a lower impact than uncoated, for most of the impact categories under study, indicating that the coating process is also appropriate to reduce the environmental impacts of urea fertilization.publishe

Life Cycle Assessment Tool for Food Supply Chain Environmental Evaluation

Food is at the centre of efforts to combat climate change, reduce water stress, pollution, and conserve the world’s wildlife. Assessing the environmental performance of food companies is essential to provide a comprehensive view of the production processes and gain insight into improvement options, but such a tool is currently non-existent in the literature. This study proposed a tool based on the life cycle assessment methodology focused on six stages of the food chain, raw materials acquisition, supplier, manufacturing, distribution, retail and wastes. The user can also evaluate the implementation of Internet of Things (IoT) technologies to reduce food waste applied in the real-world problems. The tool was validated through a case study of a food manufacturing company that prepares frozen meals via vending machines. The LCA results provided by the tool showed that food raw materials production is the main hotspot of nine impact categories. The IoT technologies’ contribution increased the company’s impact by around 0.4%. However, it is expected that employing these monitoring technologies would prevent food waste generation and the associated environmental impacts. Therefore, the results of this paper provide evidence that the proposed tool is suitable for determining environmental impacts and savings of food supply chain companies

Environmental and energy performance of residual forest biomass for electricity generation: gasification vs. combustion

Bioenergy systems have a great potential worldwide to substitute fossil fuels mainly because they may contribute to greenhouse gas emissions reduction. In Portugal, several biomass combustion-based power plants have been built in the last decade. Biomass gasification is a potential alternative to combustion but its environmental impacts should be evaluated. The goal of this study is to assess and compare the environmental and energy performance of direct gasification and combustion (both in fluidized bed) using residual forest biomass (RFB) from eucalypt in Portugal. In order to achieve the goal, life cycle assessment was applied, complemented with the Energy-Returned-On-Energy-Invested (EROI) indicator. The boundaries of the systems comprise three stages: (1) forest management, (2) collection, processing and transportation, and (3) electricity generation. The results indicate that gasification performs environmentally better than combustion in 5 out of 8 impact categories addressed. Conversely, combustion has greater EROI than gasification. After running a sensitivity analysis where the efficiency of the gasifier was changed from 53% in the base scenario to 57%, it is shown that the environmental performance of gasification improved in the range of 2–8%. The study concludes that gasification may be a good alternative to current combustion systems in Portugal.publishe

A Case Study of Human Milk Banking with Focus on the Role of IoT Sensor Technology

Human milk is the biological norm for newborn nutrition, with breast milk from the mother being recognized as the best nutritious source for infant health. When the milk is unavailable, donor human milk is the best alternative for infants with low birthweights. Growing recognition of the benefits of donor human milk has led to increasing global interest in monitoring and controlling human milk’s quality to fulfil the need for donor human milk. In response to this need, the REAMIT project proposed to adapt and apply existing innovative technology to continuously monitor and record human milk quality and signal potential milk quality issues. IoT sensors and a Big Data technology have been used to monitor conditions that may increase spoilage (such as temperature and humidity) in the transportation stage. The sensors were installed in the insulated bags used to transport the milk from the donor’s home/hospital to the human milk bank and vice versa. The temperature and humidity were collected every 30 minutes, whilst the GPS locator sent data every 2 minutes. The data are collected in the cloud using GPRS/CAT-M1 technology. An algorithm has been designed to send alerts when the milk temperature is above the pre-specified threshold specified by the organisation, i.e. above - 20°C. The experience showed evidence that IoT sensors can efficiently be used to monitor and maintain quality in supply chains of high-quality human milk. This rare product needs a high level of quality control which is possible with the support of smart technologies. The IoT technology is helping the human milk supply chain in five different aspects, namely reducing waste, assuring quality, improving availability, reducing cost and improving sustainability. This system could be extended to various supply chains of rare and precious commodities, including further medical supplies such as human blood and organs to completely avoid waste and ensure total quality in supply chains

Adapting Digital Technologies to Reduce Food Waste and Improve Operational Efficiency of a Frozen Food Company—The Case of Yumchop Foods in the UK

Cold storage is an essential operation for many food products in cold supply chains. The main objective of this kind of storage is to preserve the food products for a certain period of time. However, often due to a lack of accurate technology, humidity and temperature in food storge are not monitored in real-time, which will affect the food quality. At present, the Internet of Things (IoT) has become a very popular choice for businesses in food supply chains. This is mainly because of the easy availability of internet, which helps monitor and control the quality of food in storage and transport. In this paper, the experiences of adapting and testing IoT sensors and Big Data technology for reducing food waste in a frozen food manufacturer in the UK are presented. The temperature and humidity monitoring within the operations of this ready-to-eat frozen meal company are also expected to maintain food quality and adhere to legal food safety requirements. Our reflection of experience gained in the installation of the sensors, collecting the data to a cloud server, and conducting data analytics with the data are also described. During the implementation of the technology, the company was able to identify optimal and non-optimal storage conditions for their food products and pre-processed ingredients. This allowed the further development of an alert system and corrective action protocol assisted using the technology installed. Results of the case study evidenced and reported a thorough real-time monitoring system that was able to reduce food waste and assure product quality, which could be applied in different stages of the food supply chain. This case can influence several food businesses to start adapting technology in their routine operations to ensure food quality and safety

Real-Time Anomaly Detection in Cold Chain Transportation Using IoT Technology

There are approximately 88 million tonnes of food waste generated annually in the EU alone. Food spoilage during distribution accounts for some of this waste. To minimise this spoilage, it is of utmost importance to maintain the cold chain during the transportation of perishable foods such as meats, fruits, and vegetables. However, these products are often unfortunately wasted in large quantities when unpredictable failures occur in the refrigeration units of transport vehicles. This work proposes a real-time IoT anomaly detection system to detect equipment failures and provide decision support options to warehouse staff and delivery drivers, thus reducing potential food wastage. We developed a bespoke Internet of Things (IoT) solution for real-time product monitoring and alerting during cold chain transportation, which is based on the Digital Matter Eagle cellular data logger and two temperature probes. A visual dashboard was developed to allow logistics staff to perform monitoring, and business-defined temperature thresholds were used to develop a text and email decision support system, notifying relevant staff members if anomalies were detected. The IoT anomaly detection system was deployed with Musgrave Marketplace, Ireland’s largest grocery distributor, in three of their delivery vans operating in the greater Belfast area. Results show that the LTE-M cellular IoT system is power efficient and avoids sending false alerts due to the novel alerting system which was developed based on trip detection

A Systematic Review of Real-Time Monitoring Technologies and Its Potential Application to Reduce Food Loss and Waste: Key Elements of Food Supply Chains and IoT Technologies

Continuous monitoring of food loss and waste (FLW) is crucial for improving food security and mitigating climate change. By measuring quality parameters such as temperature and humidity, real-time sensors are technologies that can continuously monitor the quality of food and thereby help reduce FLW. While there is enough literature on sensors, there is still a lack of understanding on how, where and to what extent these sensors have been applied to monitor FLW. In this paper, a systematic review of 59 published studies focused on sensor technologies to reduce food waste in food supply chains was performed with a view to synthesising the experience and lessons learnt. This review examines two aspects of the field, namely, the type of IoT technologies applied and the characteristics of the supply chains in which it has been deployed. Supply chain characteristics according to the type of product, supply chain stage, and region were examined, while sensor technology explores the monitored parameters, communication protocols, data storage, and application layers. This article shows that, while due to their high perishability and short shelf lives, monitoring fruit and vegetables using a combination of temperature and humidity sensors is the most recurring goal of the research, there are many other applications and technologies being explored in the research space for the reduction of food waste. In addition, it was demonstrated that there is huge potential in the field, and that IoT technologies should be continually explored and applied to improve food production, management, transportation, and storage to support the cause of reducing FLW

Avaliação de ciclo de vida da produção de energia a partir de resíduos florestais

The production of bioenergy from forest biomass residues has been increasing in the last years in Portugal, mainly as a consequence of concerns related to climate change and forest fires. However, the potential environmental impacts associated with its production should be quantified to support decision-making. This quantification can be performed by using life cycle assessment (LCA), a methodology that evaluates the entire life cycle of a product or process (from the extraction of the raw materials until its end-of-life), allowing to identify the most significant stages and processes along the life cycle. Currently, there is a limited number of LCA studies concerning the production of bioenergy from forest biomass residues. In addition, those studies usually exclude the end-of-life stage (ash management) or only consider ash disposal in landfill, disregarding the valorisation alternatives. Furthermore, given the constraints on forest residues availability, it is important to assess the best use for these residues from an environmental perspective. Therefore, this thesis aims to contribute to increase the knowledge of the environmental performance of the bioenergy sector in Portugal. The two most representative combustion technologies for electricity production from forest biomass residues (grate furnace and fluidised bed) are assessed and compared using LCA throughout all stages of the value chain, namely, forest management, collection, processing, transportation, energy conversion and end-of-life. Moreover, LCA is applied to the end-of-life stage of the ash generated during the combustion of forest biomass residues to evaluate two valorisation alternatives (construction materials and soil amelioration) and compare with ash landfilling. Various scenarios are included in order to identify the most efficient option from an environmental point of view. Additionally, a consequential LCA is used to evaluate the best valorisation option for the forest biomass residues, namely, electricity, heat or bioethanol, in comparison with a baseline that entails leaving the residues in the forest soil and energy is produced from fossil fuels. The results show that fluidised bed presents smaller environmental impacts than grate furnace for all impact categories analysed. Regarding ash valorisation in construction materials, all scenarios assessed had a lower environmental impact than landfilling in all the impact categories. However, the valorisation of ash for soil amelioration presents higher environmental impacts than landfilling for some impact categories, indicating that it can potentially increase the amount of pollutants in the soil. Finally, the results of the consequential LCA indicate that the best use of the forest biomass residues is cogeneration of electricity and heat, but for some impact categories it would only perform environmentally better than the baseline under particular conditions.A produção de bioenergia a partir de resíduos florestais tem aumentado nos últimos anos em Portugal devido às preocupações relacionadas com as alterações climáticas e os incêndios florestais. No entanto, os potenciais impactes ambientais associados à sua produção devem ser quantificados para suportar a tomada de decisão. Esta quantificação pode ser realizada com recurso à avaliação de ciclo de vida (ACV), uma metodologia que avalia todo o ciclo de vida de um produto ou processo (desde a extração das matérias-primas até ao seu fim de vida), permitindo identificar as etapas e processos mais significativos ao longo do seu ciclo. Atualmente, existe um número limitado de estudos de ACV relacionados com a produção de bioenergia a partir de resíduos florestais. Além disso, esses estudos geralmente excluem a etapa de fim de vida (gestão das cinzas) ou consideram apenas a deposição de cinzas em aterro, excluindo as alternativas de valorização. Complementarmente, dadas as restrições à disponibilidade de resíduos florestais, é necessário avaliar o melhor uso desses resíduos do ponto de vista ambiental. Assim, esta tese pretende contribuir para aumentar o conhecimento do desempenho ambiental do setor da bioenergia em Portugal. As duas tecnologias de combustão mais representativas para a produção de eletricidade a partir de resíduos florestais (fornalha de grelha e leito fluidizado) foram avaliadas e comparadas através da metodologia de ACV ao longo de todas as etapas da cadeia de valor, nomeadamente a gestão florestal, recolha, processamento, transporte, conversão em energia e fim de vida. Além disso, a ACV é aplicada na etapa de fim de vida da cinza gerada durante a combustão dos resíduos florestais para avaliar duas alternativas de valorização (materiais de construção e correção do solo) e comparar com a deposição da cinza em aterro. Nesse sentido, foram incluídos vários cenários para identificar a opção mais eficiente do ponto de vista ambiental. Adicionalmente, é usada a ACV consequencial para avaliar a melhor opção de valorização dos resíduos florestais, nomeadamente eletricidade, calor ou biocombustíveis, em comparação com um cenário de referência em que os resíduos são deixados no solo florestal e a energia é produzida a partir de combustíveis fósseis. Os resultados obtidos mostram que o leito fluidizado apresenta menores impactes ambientais do que a fornalha de grelha para todas as categorias de impacte analisadas. No que respeita à valorização das cinzas nos materiais de construção, todos os cenários avaliados apresentam um impacte ambiental inferior ao da deposição em aterro em todas as categorias de impacte. No entanto, a valorização das cinzas para correção da qualidade do solo apresenta maiores impactes ambientais do que o aterro para algumas categorias de impacte, indicando que potencialmente pode aumentar a quantidade de poluentes no solo. Finalmente, os resultados da ACV consequencial indicam que a cogeração de eletricidade e calor é a melhor opção para a valorização dos resíduos florestais, embora para algumas categorias de impacte o seu desempenho ambiental só é melhor que o do cenário de referência em determinadas condições.Programa Doutoral em Ciências e Engenharia do Ambient

Medidas Explícitas e Implícitas de Atitudes Frente à Adoção e seus Correlatos Valorativos

This dissertation aimed to know the extent of which human values and attitudes explain the intention during adoption. Thus, we chose three studies. Study 1 aimed to build two explicit measures of adoption, the Attitudes toward Adoption Scale (EAFA) and the Behavioral Intention of Adopting Scale (EICA). The participation consisted of 206 people from the general population of João Pessoa (in the State of Paraíba, Brazil), mostly female (60%) with a mean age of 32 years (SD = 7.61). The EAFA presented a structure containing three factors: availability to adopt (α = 0.89), risks associated with adoption (α = 0.78) and humanitarian aspects of adoption (α = 0.78), which together explain the 45% of the total variance. The EICA, in turn, showed contained only one factor, which explains 65.8% of the total variance under Cronbach's alpha of 0.86. Study 2 aimed to: a) confirm the factorial structures of the measurements of EAFA and EICA, and b) test the explanatory model of the intention to adopt, considering antecedent variables as values and explicit attitudes toward adoption. The sample consisted of 215 people from the general population, with an average age of 33 years (SD = 7.67), mostly female (51 %). They answered the measurements from study 1, in addition to the Basic Values Questionnaire (QVB), the scale of social desirability Marlowe - Crowne (EDSMC) and a sociodemographic questionnaire. The results allowed the confirmation of the factorial structure of EAFA and unifactorial structure of EICA, while pointing to the development of a theoretical model involving the supra-personal, interactive and experimental values in explaining attitudes towards adoption and these, in turn, predicting the intention to adopt. This model is suitable for empirical data [χ²/df = 2.40, GFI = 0.99, AGFI = 0.98, CFI = 1.00, RMR = 0.02 and RMSEA = 0.00 (0.06 - 0.00), PCLOSE (p = 0.92)]. Finally, Study 3 had the following objectives: c) construct a measurement tool to examine implicit attitudes toward adoption (IAT - Adoption), and d) develop an alternative model of intention to adopt to that proposed in the study, involving values and implicit attitudes towards adoption. 50 people participated from the general population, the majority was female (54.9%), single (56.9%) with mean age of 29.55 years (SD=6.49). Besides the implicit measurement, the same instruments were used in the study 2: QVB and EICA, beyond the demographic data. Overall, the results indicated that people have implicit attitudes favorable toward to adoption and that these are inversely correlated realizable values. The second theoretical model also was proven adequate [χ²/gl =1,33, GFI = 0,90, AGFI = 0,81, CFI = 0,97 e RMSEA = 0,08 (0,001-0,17); PCLOSE (p = 0,28)]. Therefore, the objectives of this thesis were met by developing explicit and implicit measurements, and testing two alternative models of the intention to adopt, and these presented satisfactory results using the variable values, and implicit and explicit attitudes toward adoption.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESA presente dissertação teve por objetivo conhecer em que medida os valores humanos e as atitudes frente à adoção explicam a intenção de adotar. Deste modo, optou-se por realizar três estudos. O Estudo 1, objetivou construir duas medidas explícitas de adoção, a Escala de Atitudes frente à Adoção (EAFA) e a Escala de Intenção Comportamental de Adotar (EICA). Contou-se com a participação de 206 pessoas da população geral de João Pessoa (PB), sendo a maioria do sexo feminino (60%), com idade média de 32 anos (DP = 7,61). Em relação à EAFA, esta apresentou uma estrutura de três fatores: disponibilidade em adotar (α = 0,89), riscos associados à adoção (α = 0,78) e aspectos humanitários da adoção (α = 0,78), que explicam conjuntamente 45% da variância total. A EICA, por sua vez, apresentou apenas um fator, que explica 65,8% da variância total, tendo apresentado um Alfa de Cronbach de 0,86. O Estudo 2, teve como objetivos: a) comprovar as estruturas fatoriais das medidas EAFA e EICA, além de b) testar o modelo explicativo da intenção de adotar, considerando como variáveis antecedentes os valores e as atitudes explícitas frente à adoção. Contou-se com 215 pessoas da população geral, com idade média de 33 anos (DP = 7,67), sendo a maioria do sexo feminino (51%). Estes responderam as medidas elaboradas no estudo 1, além do Questionário dos Valores Básicos (QVB), da Escala de desejabilidade social de Marlowe-Crowne (EDSMC), e de um questionário sociodemográfico. Os resultados permitiram comprovar a estrutura trifatorial da EAFA e unifatorial da EICA, além de apontar para a elaboração de um modelo teórico envolvendo os valores suprapessoais, de experimentação e interativos na explicação das atitudes frente à adoção e estas, por sua vez, predizendo a intenção de adotar. Este modelo se mostrou adequado aos dados empíricos [χ²/gl = 2,40, GFI = 0,99, AGFI = 0,98, CFI = 1,00 e RMSEA = 0,00 (0,06 0,00), PCLOSE (p = 0,92)]. Por fim, o Estudo 3 partiu dos seguintes objetivos: c) construir uma medida implícita de atitudes frente à adoção (IAT Adoção), e d) elaborar um modelo alternativo da intenção de adotar àquele proposto no estudo, envolvendo os valores e atitudes implícitas frente à adoção. Participaram 50 pessoas da população geral, sendo a maioria do sexo feminino (54,9%), solteira (56,9%), com idade média de 29,55 anos (dp = 6,49). Além da medida implícita, foram utilizados os mesmos instrumentos do estudo 2: QVB e EICA, além dos dados sociodemográficos. No geral, os resultados indicaram que as pessoas apresentam atitudes implícitas favoráveis frente à adoção e que estas estão inversamente correlacionadas aos valores de realização. O segundo modelo teórico também se mostrou adequado [χ²/gl =1,33, GFI = 0,90, AGFI = 0,81, CFI = 0,97 e RMSEA = 0,08 (0,001-0,17); PCLOSE (p = 0,28)]. Logo, os objetivos desta dissertação foram cumpridos, elaborando medidas explícitas e implícitas, e testando dois modelos alternativos da intenção de adotar, tendo estes apresentado resultados satisfatórios por meio das variáveis valores e atitudes explícitas e implícitas frente à adoção