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Mineral coal is a fuel that can be used by thermoelectric plants to generate electricity, however, the solid residues of its combustion, so-called ash, cause erosion and corrosion in the internal components of boilers that operate at high temperatures, causing failures in the system. This study proposes a metallic coating based on Fe-Cr-Si, obtained using the electric arc thermal spray technique as an alternative for protecting the most affected parts of boiler tubes by the ash impact. Optical microscopy (OM), scanning electron microscopy (SEM), semi-quantitative chemical analysis by Energy Dispersive Spectroscopy (EDS), X-ray diffraction (XRD), roughness measurements, pull-off adhesion tests were used. Thermal diffusivity measurements and mathematical modelling were elaborated to evaluate the thermal exchange efficiency impact of the coating in thermoelectric plant boiler tubes. The results showed that the chemical components of the sprayed wire were well incorporated into a coating with a hardness of 730.54 ± 164.28 HV, approximately three times greater than the hardness of boiler pipes and only 11% less than the hardness of ash. XRD identified the presence of crystalline phases in the coating and adhesion tests showed that the failures were cohesive without substrate exposure. The presence of the coating reduced heat exchange of approximately 0.64% / tube length. These results showed that the proposed coating, which has a lower cost compared to others, be a promising solution to avoid unscheduled shutdowns in thermoelectric boilers.

Submitted by Leda Lopes (ledacplopes@hotmail.com) on 2022-06-02T19:45:07Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Rosilene_Silva_Dissertação.pdf: 4345182 bytes, checksum: ac26098201061883399c4bb141ec3147 (MD5) Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2022-06-06T17:53:48Z (GMT) No. of bitstreams: 2 Rosilene_Silva_Dissertação.pdf: 4345182 bytes, checksum: ac26098201061883399c4bb141ec3147 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2022-06-06T17:53:48Z (GMT). No. of bitstreams: 2 Rosilene_Silva_Dissertação.pdf: 4345182 bytes, checksum: ac26098201061883399c4bb141ec3147 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2021-09-10 Esta dissertação resulta de uma pesquisa etnográfica com as famílias eletricitárias, na cidade de Candiota (RS), e busca refletir sobre a relação destas com a Usina Termelétrica Presidente Médici. Fundamenta-se na interlocução com trabalhadores/as, eletricitários/as, aposentados/as e suas famílias, para compreender as práticas cotidianas e as narrativas dos/as interlocutores/as (ECKERT e ROCHA, 2011), considerando o habitar (CERTEAU,1998) as Vilas Residencial e Operária. O espaço urbano em Candiota constituiu-se com a implantação da Usina Termelétrica, um grande empreendimento termelétrico que utiliza o carvão como fonte de obtenção de energia elétrica. Na narrativa da aposentada eletricitária, o “distrito cresceu à sombra da usina”, salientando o quanto o cotidiano das vilas operárias é controlado pela usina (FOUCAULT, 1987), que é uma Companhia Estatal. Num processo pactuado pelo silêncio na relação entre as famílias, a cidade e a usina, observa-se os benefícios de emprego, moradia, escolarização e a usina traz às famílias eletricitárias, ao mesmo tempo em que a implantação do complexo termelétrico acarreta uma série de impactos ambientais (AGIER, 2011 e MAGNANI, 2002). As famílias moram próximas ao espaço da usina, em um ambiente disciplinado pelo trabalho, e convivem com a fumaça emitida pelas chaminés da usina (LOPES, 2006). As técnicas aplicadas na coleta de dados foram observação participante, entrevistas (BRANDÃO, 2007),prancha fotográfica (SAMAIN, 2004), e desenhos (KUSCHNIR, 2012), com registro em diário de campo realizado entre os anos de 2019 e 2020 ao caminhar pela cidade (INGOLD, 2015) This study is the result of an ethnographic research among electric power families in the city of Candiota (RS) and seeks to reflect on their relationship with the Presidente Médici Thermoelectric Power Plant. It is based on the dialogue with workers, electricians, retirees and their families, in order to understand the daily practices and narratives of the interlocutors (ECKERT and ROCHA, 2011), considering the dwelling (CERTEAU, 1998) the Residential and Worker Villages. The urban space in Candiota started with the implementation of the Thermoelectric Power Plant, a large thermoelectric enterprise that uses coal as a source of obtaining electricity. In the account of the retired electrician, the “district grew up in the shadow of the thermoelectric plant”, highlighting how much the daily life of workers' villages is controlled by the plant (FOUCAULT, 1987), which is a State Company. In a process agreed upon by the silence in the relationship between the families, the city and the power plant, the benefits of employment, housing, education and the power plant bring to electric families are observed, while the implementation of the thermoelectric complex entails a series of environmental impacts (AGIER, 2011 and MAGNANI, 2002). Those families live close to the plant, in an environment disciplined by work and live with the smoke emitted by the thermoelectric chimneys (LOPES, 2006). The techniques applied for data collection were participant observation, interviews (BRANDÃO, 2007), photographic plates (SAMAIN, 2004), and drawings (KUSCHNIR, 2012) with field diary records, carried out from 2019 to 2020 while walking through the city (INGOLD, 2015).

The planning of a new thermal power plant is linked to the various decision elements and evaluation criteria. Factors such as the plant's geographic positioning, primary energy supply points, paths, and means of delivery of this primary energy should be analyzed. Similar studies are imposed when studying the change of a thermoelectric plant's primary energy source occurs. In Brazil, several plants are currently investigating the exchange of their primary fuel from oil to gas due to the decrees issued by ANEEL. This paper presents software, which uses virtual reality to assist in the various stages of the planning process and in the analyses that must be performed. This software was developed for the Hidrotermica Group and had as the primary target the Borborema Thermoelectric Power Plant.

To attend Brazil‘s energy demands, considering the typical seasonality of Brazilian climates conditions, part of the energy available in the national electrical system has been generated from natural gas power plant (in the most recent years). This paper analyses a case of technology transfer with focus on end-users, observing theirs perception in relation to attributes of technological tool installed, a control and monitoring system. The case, developed in a thermoelectric power plant, has four organizations participants: the thermoelectric power plant that bought the technology, the company that will operate with the new technology, a research institution that helped out on the selection process and adjustments of technological tool to local necessities and the international supplier of the technology. This work used qualitative and quantitative methodology to arrive its purpose. Between the findings, there are some differences on perception of attributes for some users groups. Given the relevance of technological tool acquired, it‘s possible that communications actions and technical trainings would be necessaries to ensure that users know all the functionalities of new system, its advantages in relation to previous system and its compatibility with power plant‘s technical process. The technological dependency of foreign companies and necessities of adjustments to schedule of technological tool installation contributed for a partial transference of the technology observed, demanding future researches to check the overcoming of these limitations. Para atender as demandas de energia do país, considerando as eventuais sazonalidades inerentes às condições climáticas brasileiras, parte da energia disponibilizada no sistema elétrico nacional tem sido originada (nos anos mais recentes) a partir das usinas que geram eletricidade utilizando o gás natural. O presente trabalho possui como objetivo analisar um caso de transferência de tecnologia com foco no usuário final, observando qual é a sua percepção com relação aos atributos da ferramenta tecnológica implantada, um sistema de controle e monitoramento. O caso, desenvolvido em uma usina termoelétrica, abrange a participação de quatro organizações: a usina termelétrica que adquiriu a tecnologia, a empresa que vai operar com a nova tecnologia, um instituto de pesquisa que auxiliou no processo de seleção e ajustes da ferramenta tecnológica às necessidades locais e a empresa internacional fornecedora. Utilizou-se a metodologia qualitativa e quantitativa para o alcance dos propósitos da pesquisa. Entre os achados, verificaram-se algumas diferenças na percepção de atributos por determinados grupos de usuários. Dada a relevância do ferramenta tecnológica adquirida, é possível que ações de comunicação e treinamentos técnicos sejam necessários de modo a assegurar que os usuários conheçam todas as funcionalidades do novo sistema, suas vantagens em relação ao sistema anteriormente usado e sua compatibilidade com as rotinas técnicas da usina objeto do estudo. A dependência tecnológica de empresas estrangeiras e as necessidades de ajustes aos cronogramas de implantação da ferramenta tecnológica contribuíram para a transferência parcial de tecnologia observada, demandando pesquisas futuras para a verificação da superação desta limitação.DOI:10.5585/gep.v3i3.59

To attend Brazil‘s energy demands, considering the typical seasonality of Brazilian climates conditions, part of the energy available in the national electrical system has been generated from natural gas power plant (in the most recent years). This paper analyses a case of technology transfer with focus on end-users, observing theirs perception in relation to attributes of technological tool installed, a control and monitoring system. The case, developed in a thermoelectric power plant, has four organizations participants: the thermoelectric power plant that bought the technology, the company that will operate with the new technology, a research institution that helped out on the selection process and adjustments of technological tool to local necessities and the international supplier of the technology. This work used qualitative and quantitative methodology to arrive its purpose. Between the findings, there are some differences on perception of attributes for some users groups. Given the relevance of technological tool acquired, it‘s possible that communications actions and technical trainings would be necessaries to ensure that users know all the functionalities of new system, its advantages in relation to previous system and its compatibility with power plant‘s technical process. The technological dependency of foreign companies and necessities of adjustments to schedule of technological tool installation contributed for a partial transference of the technology observed, demanding future researches to check the overcoming of these limitations., Para atender as demandas de energia do país, considerando as eventuais sazonalidades inerentes às condições climáticas brasileiras, parte da energia disponibilizada no sistema elétrico nacional tem sido originada (nos anos mais recentes) a partir das usinas que geram eletricidade utilizando o gás natural. O presente trabalho possui como objetivo analisar um caso de transferência de tecnologia com foco no usuário final, observando qual é a sua percepção com relação aos atributos da ferramenta tecnológica implantada, um sistema de controle e monitoramento. O caso, desenvolvido em uma usina termoelétrica, abrange a participação de quatro organizações: a usina termelétrica que adquiriu a tecnologia, a empresa que vai operar com a nova tecnologia, um instituto de pesquisa que auxiliou no processo de seleção e ajustes da ferramenta tecnológica às necessidades locais e a empresa internacional fornecedora. Utilizou-se a metodologia qualitativa e quantitativa para o alcance dos propósitos da pesquisa. Entre os achados, verificaram-se algumas diferenças na percepção de atributos por determinados grupos de usuários. Dada a relevância do ferramenta tecnológica adquirida, é possível que ações de comunicação e treinamentos técnicos sejam necessários de modo a assegurar que os usuários conheçam todas as funcionalidades do novo sistema, suas vantagens em relação ao sistema anteriormente usado e sua compatibilidade com as rotinas técnicas da usina objeto do estudo. A dependência tecnológica de empresas estrangeiras e as necessidades de ajustes aos cronogramas de implantação da ferramenta tecnológica contribuíram para a transferência parcial de tecnologia observada, demandando pesquisas futuras para a verificação da superação desta limitação.DOI:10.5585/gep.v3i3.59

Izazov međunarodnoj zajednici kao i Hrvatskoj jest kako održati sigurnu i ekonomski povoljnu opskrbu energijom, a uz to smanjiti učinke klimatskih promjena i utjecaja proizvodnje električne energije na okoliš. Danas je pitanje izbora tehnologije za gradnju novih elektrana uvjetovano nizom faktora: utjecajem na okoliš, borbom protiv klimatskih promjena, tehničkim karakteristikama, mogućnošću dobave i cijenama energenta, cijenama proizvodnje, troškom investicije i mogućnošću financiranja, sigurnošću dobave energenta i sigurnošću elektroenergetskog sustava, javnošću, tržištem električne energije, regulacijom energetskih djelatnosti, subvencijama, potražnjom za električnom energijom itd.

This paper describes a miniature thermoelectric power plant made with the boiler and the water pump from an old starch iron. It also uses a computer cooling fan, which serves as electric power generator. The boiler vaporizes the water it receives from the water pump. Then, the steam is injected on the turbine of the fan, making it twirl. The voltage generated by the fan is enough to lighten a couple of LEDs. A wooden case with a chimney encloses all the referred devices., Robótica 2006 – Festival Nacional de Robótica

The deposition of coal combustion residues consumed large areas in the West Balkans. The release of effluent water from coal ash deposits contaminates ground and surface waters. Toxic trace elements entering the food chain and dust dispersion by wind erosion may negatively affect the health of local people and wild life. The aim of the RECOAL project was to assess the actual risk associated with the abundant coal ash disposal sites in the West Balkan area and to develop and test innovative low-cost methods for remediation of coal ash deposit surfaces and treatment of effluent waters. The initial project phase was devoted to risk assessment and socio-economic problem analysis. Low cost technologies were developed in bench scale experiments. Thereafter potentially feasible technical solutions were tested in the field. This included the application of amendments and cover soils to reduce transfer of toxic elements and installation of a passive aeration cascade and filter systems to reduce the pollutant load and pH of alkaline ash disposal leachate. Moreover, pollutant low-uptake crops and cultivars were identified for minimising the risk of food chain contamination. Special emphasis was put on socio-economic aspects related to the problem and its remediation. Local people were involved throughout the whole project duration. The information gathered was used to compile decision tools for a handbook which shall be accessible to local authorities, stakeholders and problem holders.

The “Handbook on treatment of coal ash disposal sites” offers guidelines for the management of established wet-disposed coal ash landfills. Decisions for the management and remediation of coal ash disposal sites require social considerations, such as what is acceptable to those directly affected and who is and should be involved in the decision-making process. The handbook provides a framework for coal ash pollution researchers and engineers, and supports policy-makers in the interpretation and synthesis of coal ash-related research for its incorporation into decision-making.

Os liquens são reconhecidos por serem muito sensíveis à poluição atmosférica, sendo assim sua utilização como indicadores biológicos da qualidade ambiental, tem sido um procedimento cada vez mais amplo. Este trabalho apresenta os resultados do monitoramento passivo realizado na área de abrangência de uma usina termoelétrica, na região sul do Brasil. Os liquens foram avaliados em cinco pontos da usina onde foi amostrado um total de 50 forófitos. Foram registrados 45 táxons, cinco destes são citados na literatura como bioindicadores da qualidade do ar. As áreas amostradas não apresentam condições adequadas para o estabelecimento e desenvolvimento da micota liquenizada, pois sofrem influência antrópica direta. A ocorrência de espécies tolerantes à poluição pode ser explicada pelo desaparecimento das espécies mais sensíveis, proporcionando mais espaço para o seu desenvolvimento. Lichens are recognized for being very sensitive to atmospheric pollution, so their use as biological indicators of environmental quality has been an ampler procedure. This work shows the results of the passive monitoring realized within the area of a thermoelectric power plant, in the Southern region of Brazil. The lichens were evaluated in five points of the power plant and a total of 50 host-trees were sampled. There were 45 taxa registered, five of them are cited in the literature as bioindicators of air quality. The sampled areas have not presented appropriate conditions for the establishment and development of the lichenized mycota, as they suffer direct anthropic influence. The occurrence of pollution tolerant species can be explained by the disappearance of most sensitive species, providing more space for their development.

This paper describes a miniature thermoelectric power plant made with the boiler and the water pump from an old starch iron. It also uses a computer cooling fan, which serves as electric power generator. The boiler vaporizes the water it receives from the water pump. Then, the steam is injected over the turbine of the fan making it twirl. The voltage generated by the fan is enough to lighten a couple of LEDs. A wooden case with a chimney encloses all the referred devices.

By modernisation of boiler feed pump drives for a thermoelectric power plant is possible to save electrical energy, to increase reliability and power plant availability, decrease maintenance costs and improve environment protection. The most significant calculations results of pump speed control modernisation by voltage and frequency controlled induction motor have been presented ; power of thermoelectric power plant (TEPP) is 320 MW.

By modernisation of boiler feed pump drives for a thermal power plant it is possible to save electrical energy, to increase reliability and power plant availability, decrease maintenance costs and improve environment protection. Energy may be saved if flows regulation, i.e. quantity of feed water is achieved by feed pump speed control by changing voltage and frequency of induction motor drives. The most significant phases and project activities have been presented based on data and power plant analysis of pumps in a specific thermal power plant.