Avaliação da incorporação de cinzas de lodo de esgoto como adição mineral em concretos de cimento Portland

O desenvolvimento das grandes cidades tem gerado um dos maiores desafios ambientais enfrentados na atualidade, que é a gestão eficaz de resíduos sólidos. A grande variedade e quantidade dos resíduos produzidos diariamente, tem tornado a destinação ecologicamente correta e sustentável destes materiais cada vez mais difícil. Dentre os vários resíduos produzidos diariamente destacam-se os lodos oriundos de estações de tratamento de esgotos, denominados de lodos de esgoto, cuja destinação final segura tem sido discutida mundialmente em diversos estudos, tendo em vista que a tendência de geração deste tipo de resíduo tende a crescer com o aumento do saneamento das cidades. Uma forma amplamente difundida nos países desenvolvidos para destinação dos lodos de esgoto é a incineração destes materiais para posterior envio das cinzas geradas neste processo a aterros sanitários. Porém, tem-se estudado formas alternativas de disposição, destacando-se a utilização destas cinzas como adição mineral em concretos e argamassas de cimento Portland. Sabe-se que o desempenho de resíduos de incineração como adição mineral em matrizes cimentícias, depende em grande parte da capacidade de atuação destes materiais como elementos pozolânicos ou como fileres, podendo estas características serem influenciadas pela temperatura de queima ao qual estes resíduos foram submetidos. Neste sentido, verificou-se com esta pesquisa a influência da temperatura empregada na queima dos lodos sépticos no índice de atividade pozolânica (IAP) das cinzas geradas como resíduo deste processo, aqui denominadas de cinzas de lodo séptico (CLS), sendo em seguida, avaliadas as implicações técnicas e microestruturais da utilização deste resíduo em teores de 10%, 20% e 30% como adição mineral em concretos de cimento Portland. Os resultados obtidos demonstraram não haver alterações significativas no IAP das CLS em decorrência da temperatura utilizada durante o processo de queima dos lodos de esgoto. Além disso, verificou-se que embora a utilização das CLS tenham provocado diminuição da trabalhabilidade dos concretos para todos os teores de incorporação, estas melhoraram a resistência mecânica à compressão, o índice de vazios, a absorção de água e o comportamento microestrutural dos concretos contendo 10% e 20% de resíduo

Avaliação do desempenho de uma cortina de estacas espaçadas, atirantada, em areia

It is presented the analysis of a retaining wall designed for the basement of a residential building, located in Natal/RN, which consists in a spaced pile wall, anchored by tiebacks, in sand. This structure was instrumented in order to measure the wall s horizontal movements and the load distribution throughout the anchor fixed length. The horizontal movements were measured with an inclinometer, and the loads in the anchors were measured with strain gages, installed in three places throughout the anchor fixed length. Measurements for displacement were done right after the implementation of each stage of the building and right after the conclusion of the building, and the measurements for loads in the anchors were done during the performance test, at the moment of the locking off and, also, right after the conclusion of the building. From the data of displacement were obtained velocity and acceleration data of wall. It was found that the time elapsed on braced installation was decisive in the magnitude of the displacements. The maximum horizontal displacement of wall ranged between 0,18 and 0,66% of the final depth of excavation. The loads in the anchors strongly reduced to approximately half the anchor fixed length, followed an exponential distribution. Furthermore, it was found that there was a loss of load in the anchors over time, reaching 50% loss in one of them

Desenvolvimento de um equipamento para avaliação do desempenho de geomantas

O controle sobre os processos erosivos é uma necessidade constatada em vários segmentos da engenharia. A movimentação de terra necessária para a execução de taludes rodoviários, por exemplo, pode resultar em taludes de corte ou aterro vulneráveis à erosão superficial. Dentre as alternativas tecnológicas para controle de erosão a utilização de geossintéticos se apresenta como uma solução potencial. A referida aplicação encontra-se em amplo desenvolvimento em alguns países como, por exemplo, nos EUA. No Brasil, a especificação de geossintéticos para controle de erosão é limitada pela ausência de caracterização desses produtos e de normas nacionais, sendo a única fonte técnica de informação, os catálogos dos fabricantes. Neste contexto, o objetivo deste trabalho é construir um equipamento e desenvolver métodos de ensaio para caracterização e avaliação de geossintéticos utilizados no controle de erosão superficial, com base na ASTM D7101. Além de um simulador de chuvas, o equipamento é composto por uma bancada de testes formada por: rampa de escoamento, mesa de suporte e núcleos de solo. Utilizando a bancada construída, foram realizados ensaios para avaliar o funcionamento do equipamento e o desempenho de uma geomanta na redução da taxa de erosão superficial. Os ensaios foram realizados com intensidades de precipitação de 100 ± 4mm/h e 150 ± 4mm/h, durante 30 minutos, com intervalo de leitura de 5 minutos. Os resultados obtidos nos ensaios sem a presença da geomanta mostraram uma perda de solo acentuada durante as chuvas simuladas, com uma iv tendência de crescimento linear da perda de solo acumulada em função do tempo de ensaio. Nos ensaios realizados com a presença da geomanta observou-se a ação de proteção do geossintético com uma redução da ordem de 90% da perda de solo acumulada para todas as intensidades de chuvas utilizadas

Método de avaliação do gerenciamento de resíduos em canteiro de obras da construção civil : proposta baseada em empresas construtoras da cidade de Natal-RN

According to great concern between the developed industrial activities and resultant impacts over the environment, an association of several factors have occurred, procedures to the efficient management of the rotation between economical development and the environment have been improved. A research in field have been realized inside building sites of companies in order to provide knowledge about the implemented and accomplish actions according to the resolution from CONAMA nº307. Trough the interview among the representations of the companies and photographic survey in loco, such as, what makes the companies implement this management, reutilization and recycling, transport and disposition. The present study had as objective: analyze the insertion of the used tools to residuals management, proposing improvements, in a way that it can be easily identified during the procedures execution in the building sites of the building companies of the city of Natal/RN. To reach the goal, in the first place a revision of the pertinent literature was performed; there for, it can be seen the relation between residues management and environment sustainability, once it happens in a continued way it may prevent the waste and reduces the risk that the activities way bring to the employees, community and environment; once found the great difficult faced with regard to labors, material, equipment, project, planning, costumer s interference, furnisher. And still, it could be verified wich materials generate greater indexes of residues in the works and the main occurrences of waste and loss. However a greater transparency is needed coming from the high administration in the commitment with the continued actions, to make it so, there must be a cultural change inside the company. There for there will be a greater productivity and quality of the under taking such as costumer s satisfaction

Proposta de um modelo de medição e avaliação de desempenho como ferramenta de gest ão - um estudo de caso num órgão público

The public sector performance has received much attention in the literature and due to that the purpose of this work is to develop a proposal for a model of performance measurement for a higher education institution unit. First, we performed a theoretical research on public organizations and private institutions of higher education, followed by a literature review on performance measurement and evaluation. This review presents some performance models that are quite frequent in the literature: Total Quality Management (Total Quality Management) - TQM and the PDCA cycle, SMART System, Balanced Scorecard and Môdef Ouanturn. In order to verify the possibility of implementing a performance measurement model for Higher Education Institutions, it was conducted a case study in a support unit of a University, located in the city of Natal, RN, Brazil. The study attempted to identify the key processes of the unit and proposed by the use of Quantum model in order to improve the management and operation of the same. The work aims to contribute to the advancement of knowledge in measurement and performance evaluation in higher education institutions that where still lacks scientific production of this subject compared to other areas. This study also identifies better practices and opportunities for improvement in processes to determine the expected performance indicators to aid a decision-making unit.

Uma avaliação comparativa de estratégias de arranjos físicos para estaleiros de construção de embarcações metálicas de pequeno porte

The present study aims to analyse, in different levels of demand, what is the best layout strategy to adopt for the small metallic shipbuilding. To achieve this purpose, three simulation models are developed for analyze these production strategies under the positional, cellular and linear layouts. By the use of a simulation tool for compare the scenarios, Chwif and Medina (2010) and Law (2009)´s methodologies were adapted that includes three phases: conception, implementation and analysis. In conception real systems were represented by process mapping according to time, material resources and human resources variables required for each step of the production process. All of this information has been transformed in the cost variable. Data were collected from three different production systems, two located in Natal RN with cellular and positional layouts and one located in Belém-PA with linear layout. In the implementation phase, the conceptual models were converted in computacional models through the tool Rockwell Software Arena ® 13.5 and then validated. In the analysis stage the production of 960 ships in a year vessels were simulated for each layout noting that, for a production of until 80 units positional layout is the most recommended, between 81 and 288 units the cellular layout and more than 289 units the linear layout

Gestão de organizações sem fins lucrativos: uma avaliação de desempenho através do balanced scorecard

The methodology Balanced Scorecard (BSC) focuses on the major critical issues of modern organizations, whether with or without profit. The measurement of the effective performance of the latter is by evaluating the successful implementation of organizational strategy. The aim of this paper is to present the development of a system of performance measurement strategy for a nonprofit organization, whose object of study is the Associação de Apoio as Comunidades do Campo - AACC, in the context of the BSC methodology of Kaplan and Norton. The methodology of this case study is an exploratory, descriptive and qualitative, and diagnose the coherence of the Strategy Map in an organization, based strategic planning from 2010 to 2012. Initially conducted a literature review covering the main aspects of strategy maps and performance evaluation involving the translation of the BSC and strategy evaluation. The main results of the proposed approach refers to evaluation of overall scores for each dimension of the BSC methodology, financial, customer, internal processes, learning and growth. These results are able to help the organization evaluate and revise their strategy and, in general, to adopt management methods more accurately. Data collection is centered on interviews with semi-structured questionnaire. The findings highlight on balancing and alignment of strategic objectives, low causality map, strategic communication insufficient and fragmented. For interviewees organizational culture is the biggest impediment to structuring a management model based on indicators and strategic process should be initiated by non-financial indicators gradually. The performance indicators of the AACC/RN portray more meritocracy operational procedures of social projects in the context of the Strategic Map determined in a shortterm over the long term. However, there is evidence of improved performance management and strategic taken as a basis of planning as both the strategic map structured. Therefore, the nonprofits need to adopt a form of management that enables planning, setting objectives and targets that provide the continuity of its activities, and generating instruments that can measure the financial performance and non-financial, in order to develop strategic actions for growth and sustainability

Avaliação do potencial do uso balanced scorecard: um estudo exploratório em Natal

Small businesses are experiencing growth scenario in emerging countries by the prospect of economic development, these countries, including Brazil, have a booming economy before the world crisis in the last five years, especially with the participation of small and medium enterprises. These factors generate increased competition and the need to expand market share through management actions in the quest for acquiring new customers. Moreover, these changes increase the need to properly use the information and organizational performance. Some national and international studies show the existence of peculiarities in small organizations, especially in environments of family management. Such particularities raise a scenario with several organizational deficiencies regarding the evaluation of their performance. In some cases, when there are static systems, traditional and focused only on the financial perspective, especially short term. Alternatively, the tools encourage strategic planning and observance of medium and long term, in many ways, whether financial, internal processes, customers, suppliers, and innovation, among others. Therefore, this study aims to identify and analyze the applicability of the system performance evaluation with emphasis on strategic and BSC - Balanced Scorecard. Regarding the research method, is classified as exploratory, with the participation of 25 companies, whose research was conducted between 2012 and 2013. Therefore, the research included the construction process and a structured questionnaire on practices and interest for the use of strategic tools, with emphasis on the Balanced Scorecard. Whose main result presented a high degree of interest in the applicability of the BSC by most of the participating institutions. Furthermore, It was observed the growing interest in using the Balanced Scorecard when it increases the company size, regardless of the area of market action. Participating companies have shown an outline of the strategic objectives and the establishment of indicators for assessing the performance due to their correlations with the BSC

Métricas de desempenho para sistema de alarmes de processos industriais

The evolution of automation in recent years made possible the continuous monitoring of the processes of industrial plants. With this advance, the amount of information that automation systems are subjected to increased significantly. The alarms generated by the monitoring equipment are a major contributor to this increase, and the equipments are usually deployed in industrial plants without a formal methodology, which entails an increase in the number of alarms generated, thus overloading the alarm system and therefore the operators of such plants. In this context, the works of alarm management comes up with the objective of defining a formal methodology for installation of new equipment and detect problems in existing settings. This thesis aims to propose a set of metrics for the evaluation of alarm systems already deployed, so that you can identify the health of this system by analyzing the proposed indices and comparing them with parameters defined in the technical norms of alarm management. In addition, the metrics will track the work of alarm management, verifying if it is improving the quality of the alarm system. To validate the proposed metrics, data from actual process plants of the petrochemical industry were used

Br-IndustrialExpert: um framework para análise de dependabilidade de processos industriais

There is a growing need to develop new tools to help end users in tasks related to the design, monitoring, maintenance and commissioning of critical infrastructures. The complexity of the industrial environment, for example, requires that these tools have flexible features in order to provide valuable data for the designers at the design phases. Furthermore, it is known that industrial processes have stringent requirements for dependability, since failures can cause economic losses, environmental damages and danger to people. The lack of tools that enable the evaluation of faults in critical infrastructures could mitigate these problems. Accordingly, the said work presents developing a framework for analyzing of dependability for critical infrastructures. The proposal allows the modeling of critical infrastructure, mapping its components to a Fault Tree. Then the mathematical model generated is used for dependability analysis of infrastructure, relying on the equipment and its interconnections failures. Finally, typical scenarios of industrial environments are used to validate the proposal

Avaliação do processo industrial da cerâmica vermelha na região do Seridó - RN

Particularly in Braziland in Rio Grande do Norte, companies manufacturing red ceramic, play an important role as agents of development to study the region Seridó- RN, specific place for carrying out the research. It is observed in this region a concentration of red ceramic industries of small size, which, despite its importance in the ceramic, they are unable to enjoy or use the new forms of administrative management and technological advances designed and offered by universities, centers of research and projects of governments, remained almost entirely outside the progress and modernization, technological and administrative. These companies still have outdated technology, and management processes, providing quality problems and standardization of end products. Upon these conditions are the companies going through crisis and struggling to survive alone and without assistance. The region of Seridó-RN, lets make a detailed case study of red ceramic companies in the region proposed from the existing theoretical and actual lifting of the condition of the product manufacturing red ceramic, allowing through this overview of the implementation of collect samples of raw materials, allowing the study of each ceramic industry that contributed to the participation of the research, which was determined parameters such as: analysis of the physical, chemical and technological properties of raw materials, characterization of the processes used, raising the technological resources considering equipment, machinery, supplies, raw materials and facilities available and its organization by type of products from companies involved in this study. The methodology consists of the following steps: collection of raw material, crushing and screening, characterization of raw materials (liquid limit, chemical analysis, mineralogical analysis, differential thermal analysis, sieve analysis), mixing, forming, cutting, drying and burning of ceramic bodies and bodies of evidence. The results showed that it was clay with distinct characteristics with respect to plasticity. With respect to the different compositions of mixtures of ceramic masses, we conclude that the ceramic properties showed a direct proportionality with increasing fraction of the clay not plastic. However, the compositions of the masses studied proved to be the most appropriate for the types of simulated clay for use in ceramics. Adopted in the ceramic processing made it possible to obtain products the resulted in consistent properties, and in some cases even exceeding the requirements of technical studies and standard-Brazilian clays to obtain ceramic products such as tiles, bricks and tiles to floor. Based on the discussions from the results obtained in the various processing steps of this work, one can draw conclusions according to the physico-chemical and mineralogical properties of raw materials, the properties of ceramic products burned and analysis. This work may be used by other researchers, private companies and governmental organizations, undergraduate students and graduate, can develop studies and future research to: develop projects to modify the furnaces; mapping projects develop and rationalize the exploitation of raw materials ;promoting reforestation and forest management; develop reduction projects and recovery of waste; develop training projects in manpower sector, and develop security projects, improving the conditions of work in the area pottery

Construção e avaliação térmica de um fogão solar tipo caixa

The present work presents a contribution in the study of modelings of transference of heat for foods submitted to the experimental tests in the considered solar oven, where the best modeling for the beefburger of chicken in study was evaluated, comparing the results, considering this food as a half-infinite(1er object considered model) and,after that, considered the chicken beefburger as a plain plate in transient regimen in two distinct conditions: not considering and another model considering the contribution of the generation term, through the Criterion of Pomerantsev. The Sun, beyond life source, is the origin of all the energy forms that the man comes using during its history and can be the reply for the question of the energy supplying in the future, a time that learns to use to advantage in rational way the light that this star constantly special tax on our planet. Shining more than the 5 billion years, it is calculated that the Sun still in them will privilege for others 6 billion years, or either, it is only in the half of its existence and will launch on the Earth, only in this year, 4000 times more energy that we will consume. Front to this reality, would be irrational not to search, by all means technical possible, to use to advantage this clean, ecological and gratuitous power plant. In this dissertation evaluate the performance of solar cooker of the type box. Laboratory of Solar Energy of the Federal University of the Great River of North - UFRN was constructed by the group (LES) a model of solar stove of the type box and was tested its viability technique, considering modeling foods submitted when baking in the solar oven, the cooker has main characteristic the easiness of manufacture and assembly, the low cost (was used material accessible composition to the low income communities) and simplicity in the mechanism of movement of the archetype for incidence of the direct solar light. They had been proposals modeling for calculations of food the minimum baking time, considering the following models of transference of heat in the transient state: object the halfinfinite, plain plate and the model of the sphere to study the necessary temperature for the it bakes of bread (considering spherical geometry). After evaluate the models of transmission of heat will be foods submitted you the processes of to it bakes of, the times gotten for the modeling with the experimental times of it bakes in the solar oven had been compared, demonstrating the modeling that more good that it portraies the accuracies of the results of the model

Avaliação da remoção de sulfeto de hidrogênio do gás natural em uma coluna de absorção

Natural gas, although basically composed by light hydrocarbons, also presents in its composition gaseous contaminants such as CO2 (carbon dioxide) and H2S (hydrogen sulfide). Hydrogen sulfide, which commonly occurs in oil and gas exploration and production activities, besides being among the gases that are responsible by the acid rain and greenhouse effect, can also cause serious harm to health, leading even to death, and damages to oil and natural gas pipelines. Therefore, the removal of hydrogen sulfide will significantly reduce operational costs and will result in oil with best quality to be sent to refinery, thereby resulting in economical, environmental, and social benefits. These factors highlight the need for the development and improvement of hydrogen sulfide sequestrating agents to be used in the oil industry. Nowadays there are several procedures for hydrogen sulfide removal from natural gas used by the petroleum industry. However, they produce derivatives of amines that are harmful to the distillation towers, form insoluble precipitates that cause pipe clogging and produce wastes of high environmental impact. Therefore, the obtaining of a stable system, in inorganic or organic reaction media, that is able to remove hydrogen sulfide without forming by-products that affect the quality and costs of natural gas processing, transport and distribution is of great importance. In this context, the evaluation of the kinetics of H2S removal is a valuable procedure for the treatment of natural gas and disposal of the byproducts generated by the process. This evaluation was made in an absorption column packed with Raschig ring, where natural gas with H2S passes through a stagnant solution, being the contaminant absorbed by it. The content of H2S in natural gas in column output was monitored by an H2S analyzer. The comparison between the obtained curves and the study of the involved reactions have not only allowed to determine the efficiency and mass transfer controlling step of the involved processes but also make possible to effect a more detailed kinetic study and evaluate the commercial potential of each reagent

Extração, caracterização e avaliação bioativa do extrato de Rumex acetosa

Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa

Jambolão (Syzygium cumini) desidratado por liofilização e secagem em leito de jorro: avaliação do impacto do processo de secagem e caracterização do potencial funcional do produto final

Tropical fruits have been extensively studied due to their functional potential attributed to the presence of natural bioactive compounds. The exotic fruit jambolan (Syzygium cumini) has been reported for its appreciable amount of phenolic compounds, especially anthocyanins and antioxidant capacity. Nevertheless, there are hardly any derived jambolan products in the Brazilian market. In addition to that, considerable volumes of fruit are lost due to their high perishability. Dried fruits have become an important fruit market segment due to its weight and volume reduction and decreased transportation and storage costs. Thus, this study evaluated the jambolan pulp submitted to spouted bed drying (JLJ) and lyophilization (JLI), besides assessing the drying impact on the final product. In order to achieve this, the process performance was calculated and compared, as well the physicochemical and bioactive characteristics (moisture, water activity (aw), solubility, hygroscopicity, density, color, structure through images obtained by scanning electron microscopy (SEM), concentration of bioactive (total phenolic compounds (TPC), anthocyanins, proanthocyanidins and ascorbic acid) and antioxidant activity. The results showed drying efficiency higher than 60% for both products and that JLJ group showed higher moisture and water activity when compared to the JLI group (p<0.05). The two types of drying were able to produce stable final product in the microbiological point of view, given that both showed aw < 0.6. The final products exhibited high solubility (73.7 to 81.6%) and low hygroscopicity (9.8 to 11.6%), desirable characteristics for dehydrated foods. Despite the losses caused by drying, the dried jambolan pulp by both methods showed high TPC (468.6 to 534.0 mg GAE/100g dm), anthocyanins (from 491.9 to 673.4 mg. eq. cyanidin-3-glicoside/100g dm), proanthocyanidins (66.9 to 76.6 mg QTE/g dm) and ascorbic acid (156.4 to 186.8 mg/100 g dm). Taken together, the results of this study reveal spouted dried and freeze dried jambolan pulp as bioactive-rich natural products with suitable physicochemical and functional characteristics to be used as food ingredients. The data also demonstrate the drying techniques as rational strategies for the exploitation of the exotic fruit jambolan