Contaminação ambiental e exploração capitalista ao meio ambiente: os resíduos sólidos na sociedade global

O mundo atual passa por uma crise ambiental sem precedentes na história, o que resulta em conseqüências ambientais perceptíveis e preocupantes. Governos e organizações internacionais têm dado maior relevância à variável ambiental como um dos principais eixos de definição das políticas de crescimento/desenvolvimento econômico, como o intuito de adequar as demandas sociais aos limites naturais. Como consequências dessa forma perdulária de produção e consumo da sociedade global temos a contaminação ambiental ampliada e diversificada. O presente artigo discute a acumulação capitalista no setor dos resíduos sólidos, partindo da hipótese da impossibilidade de se diminuir a geração ampliada dos resíduos, sendo necessário que se crie estratégias de gestão e tratamento para os resíduos baseados na atividade da reciclagem dos materiais. A parte final expõe os paradigmas da questão dos resíduos sólidos na sociedade global.

Avaliação preliminar da contaminação por BTEX, em água subterrânea de poços tubulares, no município de Natal-RN

Among the different types of pollutants typically attributed to human activities, the petroleum products are one of the most important because of its toxic potential. This toxicity is attributed to the presence of substances such as benzene and its derivatives are very toxic to the central nervous system of man, with chronic toxicity, even in small concentrations. The area chosen for study was the city of Natal, capital of Rio Grande do Norte, where samples were collected in six different areas in the city, comprising 10 wells located in the urban area, being carried out in three distinct periods March/2009, December / June/2010 and 2009, and were evaluated for contamination by volatile hydrocarbons (BTEX - benzene, toluene, ethylbenzene and xylenes), so this work aimed to assess the quality of groundwater wells that supply funding for public supply and trade in the urban area of the city of Natal, in Rio Grande do Norte, contributing to the environmental assessment of the municipality. The analysis of BTEX in water was performed according to EPA Method 8021b. Was used the technique of headspace (TriPlus TP100) coupled to high resolution gas chromatography with selective photoionization detector (PID) and flame ionization (FID) - model Trace GC Ultra, Thermo Electron Corporation brand. The procedure adopted allowed the detection of concentrations of the order of μg.L-1. Data analysis with respect to BTEX in groundwater in the area monitored so far, shows that water quality is still preserved, because it exceeds the limits imposed by the potability Resolution CONAMA Nº. 396, April 2008

Design gráfico da pluma de contaminação por compostos orgânicos voláteiss utilizando software CAD na investigação de passivo ambiental em um posto revendedor de combustíveis em Natal/RN

Among the potentially polluting economic activities that compromise the quality of groundwater are the gas stations. The city of Natal has about 120 gas stations, of which only has an environmental license for operation. Discontinuities in the offices were notified by the Public Ministry of Rio Grande do Norte to carry out the environmental adaptations, among which is the investigation of environmental liabilities. The preliminary and confirmatory stages of this investigation consisted in the evaluation of soil gas surveys with two confirmatory chemical analysis of BTEX, PAH and TPH. To get a good evaluation and interpretation of results obtained in the field, it became necessary three-dimensional representation of them. We used a CAD software to graph the equipment installed in a retail service station fuel in Natal, as well as the plumes of contamination by volatile organic compounds. The tool was concluded that contamination is not located in the current system of underground storage of fuel development, but reflects the historical past in which tanks were removed not tight gasoline and diesel

Sistema de sensoriamento eletromagnético utilizado para detecção da contaminação do óleo isolante do motor no método de elevação artificial do tipo bombeio centrífugo submerso

In the artificial lift method by Electrical Submersible Pump (ESP), the energy is transmitted for the well´s deep through a flat electric handle, where it is converted into mechanical energy through an engine of sub-surface, which is connected to a centrifugal pump. This transmits energy to the fluid under the pressure form, bringing it to the surface In this method the subsurface equipment is basically divided into: pump, seal and motor. The main function of the seal is the protect the motor, avoiding the motor´s oil be contaminated by oil production and the consequent burning of it. Over time, the seal will be wearing and initiates a contamination of motor oil, causing it to lose its insulating characteristics. This work presents a design of a magnetic sensor capable of detecting contamination of insulating oil used in the artificial lift method of oil-type Electrical Submersible Pump (ESP). The objective of this sensor is to generate alarm signal just the moment when the contamination in the isolated oil is present, enabling the implementation of a predictive maintenance. The prototype was designed to work in harsh conditions to reach a depth of 2000m and temperatures up to 150°C. It was used a simulator software to defined the mechanical and electromagnetic variables. Results of field experiments were performed to validate the prototype. The final results performed in an ESP system with a 62HP motor showed a good reliability and fast response of the prototype.

Otimização do processo de recuperação do cromo de efluentes de curtumes por microemulsões no extrator Morris

The tanning industries are those which transform animal hide or skin into leather. Due to the complexity of the transformation process, greater quantities of chemicals are being used which results in the generation of effluents with residual solids. The chromium in the residual waters generated by tanning tend to be a serious problem to the environment, therefore the recovery of this metal could result in the reduction of manufacturing costs. This metal is usually found in a trivalent form which can be converted into a hexavalent compound under acidic conditions and in the presence of organic matter. The present study was carried out with the objective to recover chromium through an extraction/re-extraction process using micro emulsions. Micro emulsions are transparent and thermodynamically stable system composed of two immiscible liquids, one forming the continuous phase and the other dispersed into micro bubbles, established by an interfacial membrane formed by surface active and co-surface active molecules. The process of recovering the chromium was carried out in two stages. The first, an extraction process, where the chromium was extracted in the micro emulsion phase and the aqueous phase in excess was separated. In the second stage, a concentrated acid was added to the micro emulsion phase rich in chromium in order to obtain a Winsor II system, where the water that formed in the micro emulsion phase separates into a new micro emulsion phase with a higher concentration of chromium, due to the lowering of the hydrophiles as well as the ionisation of the system. During the experimental procedure, a study was initiated with a synthetic solution of chromium sulphate passing onto the effluent. A Morris extractor was used in the extraction process. Tests were carried out according to the plan and the results were analysed by statistical methods in order to optimise the main parameters that influence the process: the total rate of flow (Q), stirring speed (w) and solvent rate (r). The results, after optimization, demonstrated that the best percentuals in relation to the chromium extraction (99 %) were obtained in the following operational conditions: Q= 2,0 l/h, w= 425 rpm and r= 0,375. The re-extraction was carried out at room temperature (28 °C), 40 °C and 50°C using hydrochloric acid (8 and 10 M) and sulphuric acid (8 M) as re-extracting agents. The results obtained demonstrate that the process was efficient enough in relation to the chromium extraction, reaching to re-extraction percentage higher than 95 %.

Extração supercrítica do óleo de linhaça: construção do extrator, estudo de parâmetros de processo, avaliação química e antioxidante do produto

The aim of the present study was to extract vegetable oil from brown linseed (Linum usitatissimum L.), determine fatty acid levels, the antioxidant capacity of the extracted oil and perform a rapid economic assessment of the SFE process in the manufacture of oil. The experiments were conducted in a test bench extractor capable of operating with carbon dioxide and co-solvents, obeying 23 factorial planning with central point in triplicate, and having process yield as response variable and pressure, temperature and percentage of cosolvent as independent variables. The yield (mass of extracted oil/mass of raw material used) ranged from 2.2% to 28.8%, with the best results obtained at 250 bar and 50ºC, using 5% (v/v) ethanol co-solvent. The influence of the variables on extraction kinetics and on the composition of the linseed oil obtained was investigated. The extraction kinetic curves obtained were based on different mathematical models available in the literature. The Martínez et al. (2003) model and the Simple Single Plate (SSP) model discussed by Gaspar et al. (2003) represented the experimental data with the lowest mean square errors (MSE). A manufacturing cost of US$17.85/kgoil was estimated for the production of linseed oil using TECANALYSIS software and the Rosa and Meireles method (2005). To establish comparisons with SFE, conventional extraction tests were conducted with a Soxhlet device using petroleum ether. These tests obtained mean yields of 35.2% for an extraction time of 5h. All the oil samples were sterilized and characterized in terms of their composition in fatty acids (FA) using gas chromatography. The main fatty acids detected were: palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2n-6) and α-linolenic (C18:3n-3). The FA contents obtained with Soxhlet dif ered from those obtained with SFE, with higher percentages of saturated and monounsaturated FA with the Soxhlet technique using petroleum ether. With respect to α-linolenic content (main component of linseed oil) in the samples, SFE performed better than Soxhlet extraction, obtaining percentages between 51.18% and 52.71%, whereas with Soxhlet extraction it was 47.84%. The antioxidant activity of the oil was assessed in the β-carotene/linoleic acid system. The percentages of inhibition of the oxidative process reached 22.11% for the SFE oil, but only 6.09% for commercial oil (cold pressing), suggesting that the SFE technique better preserves the phenolic compounds present in the seed, which are likely responsible for the antioxidant nature of the oil. In vitro tests with the sample displaying the best antioxidant response were conducted in rat liver homogenate to investigate the inhibition of spontaneous lipid peroxidation or autooxidation of biological tissue. Linseed oil proved to be more efficient than fish oil (used as standard) in decreasing lipid peroxidation in the liver tissue of Wistar rats, yielding similar results to those obtained with the use of BHT (synthetic antioxidant). Inhibitory capacity may be explained by the presence of phenolic compounds with antioxidant activity in the linseed oil. The results obtained indicate the need for more detailed studies, given the importance of linseed oil as one of the greatest sources of ω3 among vegetable oils

Revitalização do Rio Golandim (RN/Brasil) após décadas de contaminação por efluentes industriais e domésticos: este rio está recuperado?

Environmental pollution causes the loss of the quality of aquatic resources and also affects the health of human beings. The Golandim River is located in São Gonçalo do Amarante (RN Brazil) and had its water recovered seven years ago by measurements of parameters of the water s quality analyses physicochemistry, microbiological and heavy metals. However, it is not well established if this river is truly recovered, so this study provides a wide knowledge about the quality of these waters. Therefore, this investigation was accomplished by assays of ecotoxicology utilizing Ceriodaphnia dubia and of genotoxicity of the river s water using a biomarker Tradescantia Pallida (Trad-MCN). In set, it carried through a study of environmental perception through questionnaires that approached questions related to the profile of the interviewed one, knowledge on the environment and of the river Golandim with the community that lives in the neighborhoods of the river to diagnosis as they perceive the environment where live and its problems. The assays of the water had been carried out by collecting samples in three different sites of the Golandim River. They were collected between the periods of December 2010 (dry season in the northeast of Brazil) and July 2011 (rainy season in the northeast of). The analysis of the data allowed observing that the majority of the inhabitants are adult and presents a global vision of what it is part of the environment, the majority mentions the pollution of the river as one of the problems of the city, considering it serious. The ecotoxicology assay showed that there was not acute toxicity in all three samples collected. Meanwhile, all these three samples demonstrated significant chronic toxicity. The results from the Trad-MCN assay presented an increase in the frequency of micronucleus in one of the sites analyzed (S3) (p<0.01), in both seasons collected. On the other hand, the sites S1 and S2 did not presented a significant increase of micronucleus using this bioassay. The analyses of chemicals detected an increase in the levels of some metals, in different seasons and samples, which can be associates with some compounds found in urban and industrial areas. On the other hand, the physicochemistries parameters demonstrated that the Golandim River is recouped, when compared with the values presented at the CONAMA s legislation. However, these results indicate the presence of compounds capable of inducing chromosomal mutation in plants. On the other hand, the parameters physicistchemistries demonstrate that the river Golandim is if recouping, since when compares the values observed with the legislation of the CONAMA. All these results point to the fact that the Trad-MCN assay was sensitive and efficient biomarker for chromosomal instability and the C. dubia ecotoxicology assay was as though an efficient biomarker of toxicity of water s quality. The results from Trad-MCN associated with the ecotoxicology demonstrates that these analyses are important for environmental monitoring, once the first bioassay described above indicates alterations at the standards of cells and the other one indicates alterations at the standards of organisms. This study alerts for the necessity to carry out biological assays for the analyses of the water s quality

Uso do gpr na caracterização da pluma de contaminação gerada por hidrocarbonetos a partir de um posto de combustível na praia de Búzios/RN

This work is the application of geophysical methods, using the Ground Penetrating Radar (GPR), with the objective of survey in a subsurface plume of contamination caused by a disabled gas station. The gas station is located on the Búzios beach in southern coast of the state to Rio Grande do Norte in an Area of Environmental Protection called Bonfim-Guaraíra. The interest to develop this work was the presence of contaminants (hydrocarbons) in a well located on the desktop, previously used for the abstraction of groundwater for residents living near the site. Were raised 15 geophysical survey lines totaling 775,48 lifting and installed 4 piezometer, to confirm the contamination and prepare a pluviometric map that helped in indicating the direction of local groundwater flow, thus showing the direction of movement of the probably plume of contamination. From the processing of the GPR lines was possible to identify two likely phases of contamination according to the classification proposed by Azambuja et al 2000, which are called phase absorbed and dissolved phase

Contaminação ambiental e exploração capitalista ao meio ambiente: os resíduos sólidos na sociedade global

O mundo atual passa por uma crise ambiental sem precedentes na história, o que resulta em conseqüências ambientais perceptíveis e preocupantes. Governos e organizações internacionais têm dado maior relevância à variável ambiental como um dos principais eixos de definição das políticas de crescimento/desenvolvimento econômico, como o intuito de adequar as demandas sociais aos limites naturais. Como consequências dessa forma perdulária de produção e consumo da sociedade global temos a contaminação ambiental ampliada e diversificada. O presente artigo discute a acumulação capitalista no setor dos resíduos sólidos, partindo da hipótese da impossibilidade de se diminuir a geração ampliada dos resíduos, sendo necessário que se crie estratégias de gestão e tratamento para os resíduos baseados na atividade da reciclagem dos materiais. A parte final expõe os paradigmas da questão dos resíduos sólidos na sociedade global.

Avaliação preliminar da contaminação por BTEX, em água subterrânea de poços tubulares, no município de Natal-RN

Among the different types of pollutants typically attributed to human activities, the petroleum products are one of the most important because of its toxic potential. This toxicity is attributed to the presence of substances such as benzene and its derivatives are very toxic to the central nervous system of man, with chronic toxicity, even in small concentrations. The area chosen for study was the city of Natal, capital of Rio Grande do Norte, where samples were collected in six different areas in the city, comprising 10 wells located in the urban area, being carried out in three distinct periods March/2009, December / June/2010 and 2009, and were evaluated for contamination by volatile hydrocarbons (BTEX - benzene, toluene, ethylbenzene and xylenes), so this work aimed to assess the quality of groundwater wells that supply funding for public supply and trade in the urban area of the city of Natal, in Rio Grande do Norte, contributing to the environmental assessment of the municipality. The analysis of BTEX in water was performed according to EPA Method 8021b. Was used the technique of headspace (TriPlus TP100) coupled to high resolution gas chromatography with selective photoionization detector (PID) and flame ionization (FID) - model Trace GC Ultra, Thermo Electron Corporation brand. The procedure adopted allowed the detection of concentrations of the order of μg.L-1. Data analysis with respect to BTEX in groundwater in the area monitored so far, shows that water quality is still preserved, because it exceeds the limits imposed by the potability Resolution CONAMA Nº. 396, April 2008

Design gráfico da pluma de contaminação por compostos orgânicos voláteiss utilizando software CAD na investigação de passivo ambiental em um posto revendedor de combustíveis em Natal/RN

Among the potentially polluting economic activities that compromise the quality of groundwater are the gas stations. The city of Natal has about 120 gas stations, of which only has an environmental license for operation. Discontinuities in the offices were notified by the Public Ministry of Rio Grande do Norte to carry out the environmental adaptations, among which is the investigation of environmental liabilities. The preliminary and confirmatory stages of this investigation consisted in the evaluation of soil gas surveys with two confirmatory chemical analysis of BTEX, PAH and TPH. To get a good evaluation and interpretation of results obtained in the field, it became necessary three-dimensional representation of them. We used a CAD software to graph the equipment installed in a retail service station fuel in Natal, as well as the plumes of contamination by volatile organic compounds. The tool was concluded that contamination is not located in the current system of underground storage of fuel development, but reflects the historical past in which tanks were removed not tight gasoline and diesel

Sistema de sensoriamento eletromagnético utilizado para detecção da contaminação do óleo isolante do motor no método de elevação artificial do tipo bombeio centrífugo submerso

In the artificial lift method by Electrical Submersible Pump (ESP), the energy is transmitted for the well´s deep through a flat electric handle, where it is converted into mechanical energy through an engine of sub-surface, which is connected to a centrifugal pump. This transmits energy to the fluid under the pressure form, bringing it to the surface In this method the subsurface equipment is basically divided into: pump, seal and motor. The main function of the seal is the protect the motor, avoiding the motor´s oil be contaminated by oil production and the consequent burning of it. Over time, the seal will be wearing and initiates a contamination of motor oil, causing it to lose its insulating characteristics. This work presents a design of a magnetic sensor capable of detecting contamination of insulating oil used in the artificial lift method of oil-type Electrical Submersible Pump (ESP). The objective of this sensor is to generate alarm signal just the moment when the contamination in the isolated oil is present, enabling the implementation of a predictive maintenance. The prototype was designed to work in harsh conditions to reach a depth of 2000m and temperatures up to 150°C. It was used a simulator software to defined the mechanical and electromagnetic variables. Results of field experiments were performed to validate the prototype. The final results performed in an ESP system with a 62HP motor showed a good reliability and fast response of the prototype.