Application of a cost-benefit model to evaluate the investment viability of the small-scale cogeneration systems in the Portuguese context

Increasingly, modern society is dependent on energy to thrive. Remarkable attention is being drawn to high energy-efficient conversion systems such as cogeneration. World energy sustainability depends on the rational use of energy, fulfilling the demands without compromising the future of energy supply. The market trends foresee the use of decentralized production and the increasing replacement of conventional systems by small-scale cogeneration units as solutions to meet the energy needs of the building sector. Analysing the influence of the variables that determine the economic viability of decentralized energy production systems has become more important given the scenario of energy dependence and high energy costs for the final consumer. A cost-benefit model was developed and presented to identify the potential of small commercial scale cogeneration systems in the Portuguese building sector, based on cost-benefit analysis methodology. Five case-scenarios were analysed based on commercial models, using different technologies such as internal combustion engines, gas turbines and Stirling engines. A positive value of CBA analysis was obtained for all the tested cases, however, the use of classic economic evaluation criteria such as the net present value, internal rate of return and payback period results led to different investment decisions. The model also highlights the influence of energy prices in the economic viability of these energy power plants. The inclusion of subsidized tariffs for efficient energy production is the most contributing aspect in the analysis of the economic viability of small-scale cogeneration systems in the Portuguese building sector. Only in that case, it would be possible for an investor to recover the capital costs of such technology, even if the technical and societal benefits are accounted for

Toxicity and antihypertensive activity of brewer's spent grain extracts

info:eu-repo/semantics/publishedVersio

Improved rhamnolipid biosurfactant production by Burkholderia thailandensis E264 using agro-industrial waste

Biosurfactants are amphiphilic surface-active compounds, produced by various microorganisms, that reduce surface and interfacial tension. These compounds are attracting increasing interest over their chemical counterparts due to their advantages, such as biodegradability, high stability in extreme environments, low toxicity, low critical micelle concentrations (CMC) and the fact that they can be effectively produced from agro-industrial wastes and renewable resources. Furthermore, their diversity allows for a significant number of uses, including microbial enhanced oil recovery (MEOR), bioremediation and biomedical applications. However, the high operational costs, mainly regarding the use of expensive raw materials in the fermentation and the complex downstream processing, to yield low amounts of product restricts their industrial-scale applications. Several attempts to solve these limitations by reducing the production costs have been conducted and include the use of low-cost agro-industrial wastes and by-products as substrates. One of these low-cost substrates, that has been successfully used to produce biosurfactants by Bacillus subtilis and Pseudomonas aeruginosa strains, is Corn Steep Liquor (CSL). In this research, rhamnolipid biosurfactant production by Burkholderia thailandensis E264 was optimized using this agro-industrial waste as sole substrate. When grown in a culture medium containing CSL (7.5% v/v), this strain produced 1.77 g biosurfactant/L, which is about 2.6 times the amount of biosurfactant produced in the standard synthetic medium. The purified biosurfactant produced in the low-cost medium exhibited similar surface-active properties when compared with that produced in the synthetic medium, reducing the surface tension of water to 29.7 mN/m, with a CMC of 385 mg/L. HPLC analysis showed that the culture medium used contains about 2.6 g/L of fructose and 2.5 g/L of glucose, that are fully consumed within the first 48 h of fermentation. Since the synthetic medium contains 40 g/L of glycerol, results suggest that biosurfactant production is more efficient in the low-cost medium. Furthermore, to the best of the authors knowledge, this is the first experimental research that combines the utilization of B. thailandensis with CSL to produce biosurfactants with very optimistic results in terms of cost and production levels. The rhamnolipid-containing cell-free supernatant could be used directly in bioremediation or MEOR processes.This study was supported by PARTEX Oil and Gas, and the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund (ERDF) under the scope of Norte 2020 - Programa Operacional Regional do Norte. The authors also acknowledge to the Biomass and Bioenergy Research Infrastructure (BBRI)- LISBOA-01-0145-FEDER-022059, supported by Operational Program for Competitiveness and Internationalization (PORTUGAL2020), by Lisbon Portugal Regional Operational Program (Lisboa 2020) and by North Portugal Regional Operational Program (Norte 2020) under the Portugal 2020 Partnership Agreement, through the ERDF.info:eu-repo/semantics/publishedVersio

An integration of QFD and Fuzzy-AHP approach in hospital services, case study: a hospital in Iran

Purpose This paper shows a development of an integrated model to identify the customer needs and select the best solution to optimize the quality of healthcare systems, namely at hospitals. Design/methodology/approach After determining the patient's requirements by data gathering from experts and patients, a questionnaire was prepared to implement the Fuzzy Analytic Hierarchy Process (FAHP) method. Afterward, the requirement's weight has determined by the patients. Finally, the most important technical requirements were achieved applying the 3-phases Quality Function Deployment (QFD) model. Findings The results show that by adapting the FAHP on ideas of the patients and hospital's experts to determine the weights of patients' requirements, led to have more flotation in FAHP questionnaires in the hospital services. In this domain, adopting the decision-making tools help more precise ranking of patients' requirements. Originality/value Since high-quality urgent services are vital to the protection of human life, it is significant to precisely rank the patient’s requirements by novel methodologies. By the implementation of an integrated model using FAHP and QFD, we were able to show the improvement of the quality of an hospital in Iran. After precisely ranking the patient requirements, "increasing human resource" and "establishing requirements and instructions in initial measures and reducing medication errors", are obtained as the most important technical requirements.This work was supported by National Funds through FCT (Portuguese Foundation for Science and Technology), and the first author acknowledges the grant PD/BDE/143092/2018 provided by FCT. Also, this work has been supported by FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/202

Applying refined kano model to classify and rank customer requirements, case study: automotive industry in Portugal

Companies aim to increase the quality of products and competitiveness to gain and retain more customers. This study proposes a novel approach to identifying and prioritizing customer requirements (CRs) to improve black uniformity as a characteristic that refers to luminance differences on the surface of a display by evaluating the CRs. The refined Kano model was applied to find the significant CRs to develop the product. Firstly, 112 CRs were identified in 5 main categories (1) technical, (2) quality, (3) delivery, (4) sustainability, and (5) cost. Then, the refined Kano questionnaire was designed to categorize the CRs. An example is performed to validate the method on the automotive display' CRs. The findings showed that mechanical and delivery needs are critical CRs. Today, climate change is a significant challenge and a severe customer concern. Although sustainability's CRs not classed as essential items in the production process, suppliers must be diligent in providing them. The results help to improve the automotive industry and other production systems.This work was supported by National Funds through FCT (Portuguese Foundation for Science and Technology), and the first author acknowledges the grant PD/BDE/143092/2018 provided by FCT. Also, this work has been supported by FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/202

Spent grains: a new support for brewing yeast immobilisation

A novel carrier obtained from spent grains, a brewing by-product, was used for brewing yeast immobilisation in a continuous bubble-column reactor. The multiple-layer cell adhesion to the carrier particles resulted in a maximum cell load of 430 mg dry cell gˉ¹ dry carrier (d.c.). After 120 h of reactor operation, the cell load of DEAEmodified carrier was below 40 mg dry cell gˉ¹ d.c. while the values for non-modified carrier reached at least 100 mg dry cell gˉ¹ d.c. The changes in substrate composition on the rate of yeast attachment and on its stability were also studied

Fermentação contínua de cerveja utilizando levedura imobilizada em drêche

O ficheiro apresenta também a versão portuguesa publicada na página 41 do mesmo documento.Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BPD / 3541 / 2000

Continuous beer fermentation with yeast immobilized on spent grains : the effect of operational conditions

Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BPD / 3541 / 2000

Development of a low-cost culture medium for biopolymer production by Rhizobium viscosum CECT 908 and its potential application in Microbial Enhanced Oil Recovery

Polymers are a versatile class of compounds that play an essential role in our society, being their production estimated in more than 180 million tons per year. Nowadays, the world market is dominated by synthetic and plant-derived polymers. Biopolymers of microbial origin are characterized by their better environmental compatibility and biodegradability when compared with the synthetic ones, and their production is faster than those obtained from plants. Microbial biopolymers usually exhibit excellent rheological properties, stability at a wide range of temperatures, salinities and pH values, as well as a broad variety of chemical structures, which results in different physicochemical and rheological properties. However, despite their outstanding properties, their application is still limited by their high production costs. In this work, an alternative low-cost culture medium was developed for biopolymer production by Rhizobium viscosum CECT 908, containing sugarcane molasses (60 g/L) and corn steep liquor (1%, v/v) as carbon and nitrogen sources, respectively. Using this low-cost medium, higher biopolymer production and apparent viscosity values (5.2 g/L and 6700 mPa s, respectively) were obtained comparing with the synthetic medium (2.3 g/L and 1100 mPa s), which contained glucose and yeast extract. As a result, the cost of the culture medium necessary to produce 1 Kg of biopolymer was reduced more than 20 times. The biopolymer produced in the alternative low-cost medium exhibited better rheological properties as compared to xanthan gum, including higher viscosity at the same concentration. Furthermore, it was found to be stable at temperatures up to 80ºC, NaCl concentrations as high as 200 g/L, and high shear rates (300 s-1). Polymers are widely used by the oil industry to increase the oil reservoirs productivity during the tertiary oil recovery processes. In sand-pack column assays performed using a heavy crude oil (40ºC= 170 mPa s), this biopolymer produced using the low-cost medium demonstrated a better performance than xanthan gum, recovering almost 50% of the entrapped oil. Results herein obtained highlight that the R. viscosum biopolymer is a promising candidate for application in MEOR as an alternative to the conventional microbial and synthetic polymers currently used.info:eu-repo/semantics/publishedVersio

A construtibilidade em projectos de edifícios para o ensino superior público em Portugal

A Construtibilidade é definida como “The optimum use of construction knowledge and experience in planning, design, procurement, and field operations to achieve overall project objectives “ - A aplicação de forma optimizada dos conhecimentos e das experiências da construção durante as fases iniciais do projecto, de planeamento e concepção, de forma a facilitar o cumprimento dos objectivos do projecto. O correcto entendimento deste conceito e da sua integração nas metodologias de projecto, durante o período global do seu ciclo de vida, constitui-se como uma potente ferramenta para a construção dos objectivos de projecto e para a satisfação dos requisitos do dono de obra. Os dezassete princípios da Construtibilidade, aplicáveis ás diferentes fases do ciclo do projecto, são orientadores dos procedimentos de gestão e de decisão do projecto, procurando melhorar, do ponto de vista da Construtibilidade, as diferentes soluções de concepção. A implementação da Construtibilidade pode ser feita com recurso a meios mais ou menos formais, que devem ser escolhidos em função de factores diversos como o tipo, dimensão e complexidade do projecto, o tipo de dono de obra, as formas de contratação de projectistas e construtores, o tipo de organizações funcionais intervenientes, entre outros. Entre estas metodologias de implementação contam-se as revisões da construtibilidade e os programas da construtibilidade