Metodologia para implantação de um sistema de disposição de rejeitos em minério de ferro na região do semiárido: estudo de caso

Tailings dams are structures that aims to retain the solid waste and water from mining processes. Its analysis and planning begins with searching of location for deployment, step on which to bind all kinds of variables that directly or indirectly influence the work, such as geological, hydrological, tectonic, topographic, geotechnical, environmental, social characteristics, evaluation security risks, among others. Thus, this paper aims to present a study on the most appropriate and secure type of busbar to design a layout structure of iron ore tailings, taking into account all the above mentioned variables. The case study involves the assessment of sites for location of dams of tailings disposal beneficiation of iron mine to be built in Bonito, in the municipality of Jucurutu in Seridó Potiguar. For site selection among alternatives, various aspects of the current state of the art were considered, one that causes the least environmental impact, low cost investment, adding value to the product and especially the safety of the implanted structure mitigates the concern about induced earthquakes as a result of liquefaction wastes somatized by dams in the region, as the tilling of Mina Bonito is located practically in the hydraulic basin dam Armando Ribeiro in environmental protection (APA). The methodology compares induced by dams in the semiarid region with the characteristics of the waste disposal and sterile seismicity, taking into account the enhancement of liquefaction by the action of seismicity in the Mina Bonito region. With the fulcrum in the methodology, we indicated the best busbar type for disposal of tailings from iron ore or combination of them, to be designed and built in semiarid particularly for Mina Bonito. Also presents a number of possible uses for the tailings and in engineering activities, which may cause processing to the common good.

Desenvolvimento de cerâmica vermelha utilizando rejeitos da construção civil

The Industry of the Civil Construction has been one of the sectors that most contribute to the pollution of the environment, due to the great amount of residues generated by the construction, demolition and the extraction of raw material. As a way of minimizing the environmental impacts generated by this industry, some governmental organizations have elaborated laws and measures about the disposal of residues from the building construction (CONAMA - resolution 307). This work has as objective the reutilization of residues compound of sand, concrete, cement, red bricks and blocks of cement and mortar for the production of red ceramic, with the objective of minimizing costs and environmental impacts. The investigated samples contained 0% to 50% of residues in weight, and they were sintered at temperatures of 950°C, 1000°C, 1050°C, 1100°C and 1150°C. After the sinterization, the samples were submitted to tests of absorption of water, linear retraction, resistance to bending, apparent porosity, specific density, XRD and SEM. Satisfactory results were obtained in all studied compositions, with the possible incorporation of up to 50% of residues in ceramic mass without great losses in the mechanical strength, giving better results to the incorporation of 30% of residues in the fabrication of ceramic parts, such as roofing tiles, bricks masonry and pierced bricks

Desenvolvimento de cerâmica vermelha utilizando rejeitos da construção civil

The Industry of the Civil Construction has been one of the sectors that most contribute to the pollution of the environment, due to the great amount of residues generated by the construction, demolition and the extraction of raw material. As a way of minimizing the environmental impacts generated by this industry, some governmental organizations have elaborated laws and measures about the disposal of residues from the building construction (CONAMA - resolution 307). This work has as objective the reutilization of residues compound of sand, concrete, cement, red bricks and blocks of cement and mortar for the production of red ceramic, with the objective of minimizing costs and environmental impacts. The investigated samples contained 0% to 50% of residues in weight, and they were sintered at temperatures of 950°C, 1000°C, 1050°C, 1100°C and 1150°C. After the sinterization, the samples were submitted to tests of absorption of water, linear retraction, resistance to bending, apparent porosity, specific density, XRD and SEM. Satisfactory results were obtained in all studied compositions, with the possible incorporation of up to 50% of residues in ceramic mass without great losses in the mechanical strength, giving better results to the incorporation of 30% of residues in the fabrication of ceramic parts, such as roofing tiles, bricks masonry and pierced bricks

Avaliação da ecotoxicidade de percolados em áreas de disposição de resíduos na região metropolitana de Natal/RN

Leachates are effluent produced by decomposition of solid waste, they have complex composition and can be highly toxic. Therefore such percolated liquid should be collected and treated properly to avoid environmental contamination of soil and of water bodies. The objective of this study was to evaluate the toxicity through ecotoxicological tests with Ceriodaphnia dubia (Cladocera - Crustacea) of percolated liquids generated in two different systems of municipal solid waste (MSW) disposal in the city of Natal/ RN: A Sanitary Landfill in the Metropolitan Region of Natal/ RN, and in a dump off area. Furthermore, it was evaluated the possible contamination of the underground water of the dump off area. Two monthly samples were taken at four points between the months of May/2009 and January/2010. The Point "A" corresponds to the end of the pond leachate treatment in ASRMN; The Point "B" corresponds to a containment pond at the dump. The Point "C" is an area near one of the cells of the dump off area where the leachate outcrops; The Point "D" stands for an underground water well at the area. The last point, called "E" was sampled only once and corresponds to the slurry produced by temporary accumulation of solid waste in the open area of the dump. The ecotoxicological tests, acute and chronic, followed the ABNT 13373/2005 rules, with some modifications. The samples were characterized by measuring the pH number, the dissolved oxygen (DO), the salinity, BOD5, COD, Cd, Cu, Pb, Cr, Fe, Mg, Ni, and Zn. At Point A, the average number of EC50-48h ranged between 1.0% and 2.77% (v/v), showing a high toxicity of the leachate to C.dubia in all months. To this point, positive correlations were found between the EC50- 48 with precipitation. Negative correlations were found between the EC50- 48h with salinity. At point B there was no response of the acute exposure of organisms to the test samples. At point C the EC50-48h ranged from 17.68% to 35.36% in just two months of the five ones analyzed, not correlated meaning. Point D, the EC50-48h level ranged between 12.31% and 71.27%, showed a negative correlation with, only, precipitation. Although it was observed toxicity of underground water in the Landfill Area, there was no evidence of water contamination by leachate, however, due to the toxic character of this water, additional tests should be conducted to confirm the quality of water that is used for human supply. At point E there was no acute toxicity. These results support the dangers of inappropriate disposal of MSW to water bodies due to the high toxicity of the leachate produced highlighting the necessity of places of safe confinement and a treatment system more effective to it

Diagnóstico Socioambiental da disposição final dos resíduos sólidos no distrito de Guajiru São Gonçalo do Amarante/RN, ressaltando a situação socioeconômica dos catadores

One of the concerns of this century is with the handling and the final destination of urban solid waste (RSU), where depending on the form as they will be made use, they can cause diverse problems, they are of ambient or social order, being able to generate the loss of the quality of life and illnesses to the population, of direct or indirect form. The objective of the present work was to diagnosis the environmental partner situation of the Final Destination of the urban solid residues in the District of Guajiru, city of São Gonçalo do Amarante/RN, standing out the partner-economic situation of the scavengers. The research was carried through in the period of March of 2008 the October of 2009, with a methodology developed through analyzes them of documents made available for the state ambient agency, the Air base of Christmas and managing agencies of the city. For collection of the date, it was used directly application of the questionnaire with 20 existing scavengers in points of destination of residues, evaluation of the old place of final destination through the use of the spread sheet of the IQR (Index of Quality of the Residues), developed for the CETESB, identification of the matter dump and photographic register. For effect of treatment of the data, a descriptive analysis with regard to the answers of the interviewed scavengers was carried through. The acquired date, Scale had been according to tabulated and analyzed in Excel 2003, where they had been generated graphical to observe the behavior of the data. The results show that of the twenty interviewed scavengers, 35% possess age between 20 and 30 years; 75% possess incomplete basic education; 60% inhabit in houses of waal or huts (cardboard or wood); 55% do not make use of system of water supply and system of sanitary exhaustion; with regard to income monthly for scavengers, 35% had presented income between R$ 200,00 and R$300,00 and 20% possess income above of R$ 500,00 for possessing another source of income; 80% of the interviewed ones, use some type of equipment of individual protection; In the year of 2009, confirming what it was informed by the State agency of Environment, during the field visit, we evidence that the city of Is Gonçalo do Amarante, currently, destines its residues in Sanitary landfill of São Region Metropolitan of Natal in the District of Massaranduba in the city of Ceará-Mirim, after some interventions of the State Public prosecution service. However, in the district of Guajiru some diggings still exist that today are used as final destination of RCD' s (Residues of Construction and Demolition) of the cities of Natal and São Gonçalo do Amarante, as well as private dumps that are used by scavengers that deviate the final destination (Sanitary landfill) of the residues of the great generators (supermarkets, shopping Center and hotels), with presence of urubus, generating a new ambient problem for the city and the aeroportuária security. Ahead of this scene, the study it suggests viable alternatives for the elimination of the private dumps and for the social situation of the escavengers, aiming at to improve its quality of life and 10 to minimize the ambient impacts caused by the inadequate destination of the solid waste in the community of Guajiru, São Gonçalo do Amarante/RN, being able to contribute so that the public managers carry through action in the handling and the control of the final destination of the urban solid waste

Influência da adição de rejeitos cerâmicos nas propriedades de cerâmica vermelha da região do Recôncavo Baiano

The study of the physical and mechanic properties is an analysis of unquestioned importance on the production of the ceramic materials. In the region of the Recôncavo Baiano, there are ceramic and small brick factories, that still use rudimentary techniques, where the necessity of characterization of raw materials is denounced by the quality of the final product. The present work has for objective to study the behavior of the clay proceeding from the region of the Recôncavo, between the cities of Candeias and Camaçari/Ba, with addition of 5, 10 and 15% by weight of brick scraps, trying to optimize the physic and mechanical properties of the final product, aiming a better possibility of being manufactured, mechanic resistance, low linear retraction and water absorption. The brick scraps and the clay were characterized by FRX, DRX, TG, ATD and the granulometric analysis. Samples for testing where prepared by uniaxial pressing at 25Mpa, in 60x20x5mm size. The evaluated technological properties were: linear retraction, water absorption, apparent porosity and flexural strength. The samples were burned in electric oven in the temperatures of 850º, 950º and 1050ºC and compared its mechanical properties and the gresification. With addition of 15% by weight of brick scraps and burning at 900º-1000ºC the samples showed properties superior to that clay

Utilização de resíduos de rochas ornamentais na produção de cerâmica branca

The marble and granite waste come from the process of mining of those ornamental rocks for use in the building industry. Brazil is one of the largest producers of blocks or finished products of ornamental rocks, extracting about 5.2 tons / year. The largest national producers are the states of Espírito Santo, Minas Gerais and Bahia which account for 80% of the Brazilian production. However, the waste total amount during processing of these blocks reaches 40% of the total. The use of the waste produced by this industry in white ceramics could be a form of disposition, because these materials, are thrownasa mud directly at decantation ponds, wastelands or in rivers, without any treatment. The present work has as main purpose to study the influence that reject of the ornamental rocks on the physical and mechanical properties of white ceramics. X-Ray characterizations of raw materials by were performed X-Ray fluorescence, X-Ray diffraction, granulometric, thermogravimetric and thermodiferencial analysis, five formulations were made (0, 10, 20, 30, 40% in granite weight) wich were burned at three temperatures: 1100°C, 1150°C and 1200ºC with 60 minutes of sorling time. After sintering, the samples were submitted to different analyser absorption of water, linear retraction, apparent porosity, apparent specific mass, flexival stronght, and scanning were obtained microscopy. Compatible technological properties within the limits demanded for the production of porcelainized stoneware

Incorporação de lodo de esgoto na massa cerâmica para fabricação de tijolos maciços: uma alternativa para a disposição final de resíduo

The disposal of sewage sludge is a growing problem face up to management of sanitary sevices. Otherwise, because its making process characteristic, the Ceramic Industry can tolerate the presence of this wastes as raw material. This study has as object to confirm the use of the sewage sluge in the Ceramic Industry like a sustentable alternative for its disposal. Futhermore, this study quests to evaluate the maximum proportion for incorporation of sludge wich result in technically and enviromentally suitable bricks. For found this proportion, the research consisted of (1) making of bricks in full scale, adde up 0%, 5%,10%, 15%, 20%, 25%,30%, 35% e 40% sludge, with size 220x105x45 mm, hand-molded by rammer and baked by industrial kiln; and (2) tecnical and enviromental evaluation of this bricks, according to Brazilian norms. The raw material uses were two distinct clays come from Goianinha/RN and sewage comes from a septic system tank and pumped into tank vehicle, of Natal/RN. The technical evaluation allowed to conclude the addiotion of the sludge brings about signifcant lost of mass and the water absorption grew up according to increase of sludge: every sludge-amended clay bricks absorved more water than control group. Thus, the compressive strength was signicantly decreased because the increase of sludge: bricks with 5% sludge added lost 45% of strength achieved at control group; the bricks made with 10 and 20% lost almost 70% of bigger strength. With up to 25% sludge added to the bricks, the streght decreased over 90%. Concerning heavy metal leaching, the two maximum proportion wich have tecnical approval, it means bricks sludge added with 15 and 20%, can say there is no risk of enviromental contamination using those bricks. This way, in this work context, it can to conclude the maximum proportion atends the technical and enviromental criterion is 20%

Otimização do Uso das Águas da Barragem Santa Cruz-RN

The semiarid potiguar presents a quite discrepant. It is a region with one of the highest rates of artificial lake the world, but the policy of building dams to mitigate the problem of water scarcity does not solve, given that they have not demonstrated the ability to ensure supply human priority during periods of great drought and fail to solve the widespread demand existent in the semiarid. This work aims to present the optimal allocation of water, according to multiple uses and limited availability of water resources in the reservoir, from the simulation of the operation of the same, with the application of techniques to support decision making and performance evaluation alternatives for water use. The reservoir of Santa Cruz, the second largest reservoir of RN with storage capacity of approximately 600 million cubic meters, located about 20 km from the town of Apodi in RN, was conceived as a way to promote economic development in the region as well as the water supply of nearby towns. The techniques used are the simulation model of network flow ACQUANET and also the set of performance indicators. The results showed that the container has the capacity to serve up to 3,83m3/s flow required by existing uses, without any compromising the same. However, it was also observed that all anticipated future demands are implemented it will generate failures in meeting some uses

Incorporação do lodo de tanque séptico como matéria-prima de uma mistura asfáltica

In Natal/RN, 68% of the population uses some kind of individual system for their domestic sewers treatment, being that the most used it is septic tank, followed by sumidouro. Every treatment system of sewers, usually used, generates a by-product denominated sludge. That residue presents some components, in its constitution, undesirable under the environmental and sanitary point of view. In such case, to assure that the system treatment has satisfactory results, it is necessary to do the adjusted disposition of the sludge sewage. Several countries are looking for technical alternatives for the use and disposition of residues. Under technical and environmental conditions appropriate, these materials can be used, decreasing the consumption of the natural resources and the treatment need, storage or elimination of the wastes, what decrease the risks created. Some of the alternatives of recycling of the sludge sewage are: the application in the agriculture, in the production of energy and as raw material in the civil construction. This study evaluated asphalt mixtures behavior that partially substituted conventional aggregates by septic tank sludge. The septic tank sludge gave origin to two raw materials called raw sludge and sludge ash. The raw sludge was put as a small aggregate and the sludge ash as filler. In the first experiment it was made a comparison between the mixture with conventional aggregates and the mixtures that replaced sand by raw sludge in the proportions from 5% to 40%. In the second experiment, it was made comparison between mixtures with 1%, 2% and 3% of sludge ash and cement. The stages developed along the study were: physical characterization of the conventional materials; physical, chemistry, thermal, mineralogical characterizations and analysis of environmental risk of the raw sludge; physical characterization and analysis of environmental risk of the sludge ash; analysis of the mixtures performance through its volumetric and mechanical characteristics; forecast of the mixtures susceptibility in the moisture presence. For the grain size composition used and with the percentage asphalt adopted, the mixtures with up to 7,5% of raw sludge in his composition attend to the National Department of Transports Infrastructure (DNIT) specifications. However, in agreement with the mixtures susceptibility in the moisture presence, the mixtures with addition of raw sludge don't present satisfactory acting. In such case, they could be used in arid and semi-arid areas. The raw sludge application in mixtures increased their voids volume and their stability. However, it damaged mixtures adhesiveness. Mixtures with sludge ash and with cement presented similar behavior. However, mixtures with sludge ash presented a better performance than mixtures with cement as for their stability and their tensile strength ratio. The mixture with 1% of sludge ash is better. The wastes studied don't represent environmental risk

Avaliação da genotoxicidade das águas sueprficiais da Barragem Engenheiro Armando Ribeiro Gonçalves, Assu/RN

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Engenharia nos sertões nordestinos: o Gargalheiras, a Barragem Marechal Dutra e a comunidade de Acari, 1909-1958

In Brazil, between the late nineteenth and early decades of the twentieth, polytechnic engineers assumed an important role in discussing the establishment of a modern country. The problem of drought in northeastern Brazil gave the professionals performance, within an interventional process more mounts, the conception plans and measures for the purposeful integration of the territory afflicted. With the foundation of Inspetoria de Obras Contra as Secas (IOCS), in 1909, the actions to combat drought and would be institutionalized, them, studies performed out by technical and scientific committees would be systematically applied in the Brazilian Northeast. So, This work was central objective understand the historical process inplantation of a whole infrastructure of modern character by professional technical and their consequences within the Northeast Geographic space, in specific, in the municipality of Acari in the State of Rio Grande do Norte, in the first half of the twentieth century. The politics of the government, through technical education and scientific engineers polytechnics, would emphasize, during the twentieth century, the building of dams, and irrigation canals, wells, railways, highways, between other elements, that would soon transform the physical space-northeast, specifically, the territory acariense. These works began to contribute to the setting of man backcountry their land, promote the regular practice of agriculture even in periods of drought and, the integration, especially, economic of territory acariense the other producing regions of Rio Grande do Norte and the Northeast as well as promoting the modification of the landscape of the world backcountry. These actions functioned as elements of modernity and progress that transformed the space by favoring by favoring the formation of urban networks (urban) in this space

Utilização de rejeitos de Caulins na Síntese de Zeólita A

Three studies were performed using tailings kaolin for the synthesis of zeolite A. The first synthesis of zeolite A was performed using a kaolin waste generated from the beneficiation of kaolin for paper production process was studied. The kaolin waste was thermally activated at a temperature range of 550-800°C. For comparison was performed a synthesis pattern of Zeolite A(procedure IZA). The prepared materials were characterized by 27Al MAS NMR, X-ray diffraction and scanning electron microscopy with microprobe rays. The pre-tramento proved to be the most appropriate and suitable temperatures are between 600 and 700°C. Observed the formation of zeolite A in all materials, reaching 52% crystallinity, and the presence of phase sodalite and amorphous material. The second study was the use of a highly reactive metakaolin originating from the Jari region in the synthesis of zeolite A by a new method of hydrothermal synthesis. The zeolite is obtained pure and highly crystalline employing the Jari kaolin calcined at 600 ° C for 2h when the transformation to metakaolin occurs. Get to zeolite phase A at 4pm. The best crystallization time was of 24 h afforded a crystallinity of 67.9%. The third study was the evaluation of the NaOH / metakaolin and crystallization time on the synthesis of zeolite NaA from a sample of kaolin waste, named Kaolin Coverage. The experiments were performed using statistical design (axial points) and rejoinder the center point. The samples were characterized by X-ray diffraction (XRD), scanning microscopic analysis and chemical analysis using an EPMA microprobe. The results showed that a relationship exists between the amount of NaOH added and the crystallization time. The experiment performed using the lowest ratio NaOH / metakaolin (0.5) and shorter (4 h) produced an amorphous material. The increase ratio of NaOH / metakaolin and crystallization time leads to formation of a more crystalline NaA phase, but the presence of phase with sodalite as impurities

Comunidade fitoplanctônica como discriminador ambiental em açude eutrófico tropical semiárido (Barragem Armando Ribeiro Gonçalves, RN) e divulgação científica para reflexão social

The knowledge of the phytoplankton community, as an integral and dynamic processes of eutrophication, provides information essential for proper management and handling. A growing problem of cyanobacteria in reservoirs around the world as a result of artificial eutrophication processes, generating a particular concern, because some species produce cyanotoxins, which can cause adverse effects on human health. The present work aims to characterize the spatial and temporal dynamics of phytoplankton, assessing their potential as ecological indicator of water quality in reservoirs semiarid region. The samples of water were collected monthly between 2009 and 2011, at three points along the dam Armando Ribeiro Gonçalves / RN. In each sample were measured physico - chemical analysis of water and biological components. We conducted a scientific dissemination activity, with distribution and reading primer on eutrophication, informative talk about water quality, questionnaires and performing a play in a public school in the city of Itajá / RN. The reservoir was considered eutrophic in three points, taking into account the values of chlorophyll -a and phosphorus, adopted to characterize eutrophic environments of semi-arid areas. High density of cyanobacteria, with a maximum value of 2.227.862 cél.ml- 1 and minimum of 43.456 cél.ml- 1 was recorded in lentic and semilêntico points throughout the study, exceeding the levels of drinking water (20.000 cél.ml- 1) established in 2.914/2011 Ordinance of the Ministry of Health of Brazil. All samples contained microcystin, and 44 % had values superiores1μg L- 1. The thermal pattern of the water column showed micro stratifications with differences of less than 1 ° C from five feet deep. The distribution pattern was the type profile clinogrado with oxygen deficit in the bottom of the reservoir. Oxiclina from 10 meters depth was observed during the rainy season (May-June) in the two years of study. The phytoplankton community was represented by 10 functional groups: S1, M, H1, Lo, P, F, Sn, P, W2 and R. The assessment of the ecological status of the system by the index Q showed poor water quality. The results of the study show that the vertical variations were less pronounced than the seasonal variations of cyanobacteria and phytoplankton community in general in the reservoir. The presence of cyanotoxins confirms the need for the monitoring of water quality and measures to reduce eutrophication in water supply reservoirs semiarid RN and demonstrates the challenge for water managers and health authorities to ensure water quality and consequently minimize risks to human health. Compared to the lecture, the primer was considered more efficient in sensitizing the participants, featuring a dynamic practice, differentiated learning, create opportunities for students to rethink attitudes of respect and care for the environment, and shall have the opportunity to learn the subject content from your reality and living environment. The knowledge generated from the activity of scientific were seen as essential for raising awareness of some of the region`s environmental problems , such as eutrophication

Alterações dos parâmetros climáticos no município de Apodi-RN, antes e após a construção da barragem Santa Cruz do Apodi, e formação do lago

Este trabalho teve como objetivo principal analisar as mudanças ocorridas no clima local onde o município de Apodi/RN está inserido, em virtude da construção da Barragem Santa Cruz do Apodi. Foram utilizadas para o tratamento dos dados climáticos precipitação pluviométrica, umidade relativa do ar e temperatura técnicas estatísticas como Desvio Padrão, Teste T, Coeficiente de Variação e Média aritmética, além do modelo matemático. Para o balanço hídrico foi aplicado o método de Thornthwait (1948), considerando dois períodos em análise: o anterior e posterior a construção da Barragem Santa Cruz do Apodi, respectivamente 1995 e 2005. os resultados obtidos permitiram inferir que a hipótese inicial levantada se confirma, ou seja, a construção da Barragem Santa Cruz do Apodi, está influenciando diretamente numa alteração no que concerne à condição atmosférica local, especialmente no parâmetro umidade relativa do ar. Quanto ao balanço hídrico, observou-se a predominância do déficit hídrico especialmente entre os meses de junho a janeiro, período de estiagem; um excedente ocorrente entre os meses de maio e junho, conseqüente do período chuvoso; e uma reposição hídrica antecedendo e sucedendo este período, chuvoso, ou seja, compreendendo os meses de fevereiro a junho. Todas as considerações e análises poderão contribuir para o planejamento de abastecimento d´água, a irrigação, auxílio na previsão de enchentes e estiagens, bem como o manejo do uso da água subterrânea