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Among the waste generated at oil refineries, secondary sludge from biological wastewater treatment processes (activated sludge systems) stands out. This paper aimed to assess the use of anaerobic digestion (AD) to treat sludge by SWOT (Strength, Weakness, Opportunity, and Threat) analysis, ranking the different factors based on sustainability criteria. Additionally, the SWOT factors were matched (TOWS matrix) to help interpret the results. AD was found to be compatible with sustainability. The results demonstrated that the strength of AD (reduced organic load) compensates for its weaknesses (need for operational control and initial implementation costs), thereby avoiding the threat (sludge composition) and making the most of the opportunity (lower disposal cost). AD and co-digestion (added with food waste) used to treat oil refinery sludge showed that around 60% of the factors analyzed were confirmed experimentally. It was concluded that AD should be considered in the sustainable treatment of oil refinery waste activated sludge, especially when mixed with other readily biodegradable wastes.

Anaerobic digestion (AD) is a potential treatment for secondary sludge from refineries.AD is compatible with sustainability.Anaerobic co-digestion of refinery sludge contributed positively to sustainable treatment.The strength (reduced organic load) of AD counteract its weaknesses (operational control and implementation costs).The threat of AD (sludge composition) should be avoided and the opportunity (low disposal cost) leveraged.

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A flare stack is an indispensable device in the oil and gas industry for allowing the safe combustion of gases into the atmosphere, especially during emergencies. However, it is not ideal for the routine disposal of gaseous waste, as it is subject to meteorological influences and poor operational control. In addition, it can be affected by toxic currents and thus pose a potential risk of odors; in view of this, an assessment must be made of the implications of burning on the environment and health. Atmospheric dispersion modelling has proved to be a very useful tool for this purpose. In light of this, an attempt has been made in this work to evaluate the impact of H2S on the well-being (odor perception) of the community in the surrounding area of an oil refinery, where the temporary burning of rich gas in H2S occurs in a chemical flare, and operational factors have an influence on atmospheric dispersion. The odor assessment was carried out with the aid of AERMOD which was adapted to estimate the maximum odor concentration for very short periods by means of peak-to-mean ratios. The results showed that H2S detection can reach a probability rate of 42% at 3.5 km distance from the flare (in a time interval of 5 s) with a relatively high degree of annoyance (3.0 AU). However, some operational procedures can reduce the probability of odor detection to 29% and the degree of annoyance to 2.6 AU.

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The technology of anaerobic co-digestion to treat the excess biological sludge discharged from activated sludge systems in oil refineries was evaluated in bench scale experiments. Mixing food waste rich in fruits and vegetables with this sludge increased the reduction of volatile solids and biogas yield. An experimental design indicated that the best co-digestion condition was the use of waste activated sludge without previous dewatering (3.5% total solids) and food waste in an 80:20 ratio (% v/v), without the addition of inoculum. After 45 days at 35 °C, this condition resulted in volatile solid (VS) removal of 52% and biogas yield of 80.7 mL biogas/g VSadded, against only 19% and 38.5 mL biogas/g VSadded in mono-digestion of sludge alone. Anaerobic co-digestion demonstrates promising results and the potential for a simple and effective treatment method for excess biological sludge generated at refineries.

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This paper presents an eco-efficiency analysis of five scenarios for treating a petrochemical unit effluent defined sequentially to increase the water reuse rate to the limit condition of Zero Liquid Discharge perspective. The base process, consisting of reverse osmosis, an evaporator and crystallizer, displayed pretreatment alternatives the addition of antifouling agents, desupersaturation of barium ions and coprecipitation of low solubility salts to increase osmosis efficiency. The eco-efficiency analysis applied the life cycle approach to verify environmental and energy performances and determined the costs of the treatment unit installation and operation for a time horizon of 9.5 years. The pretreatment increased water recovery during osmosis from 84% to over 97%. The environmental-energetic analysis indicated a strong influence of electric energy, consumed mainly during the thermal stages of the treatment, and of the chlorine-derived compounds used in the pretreatment. Also due to pre-treatment, it was possible to reduce impacts in terms of Global Warming Potential by up to 59%, and in Primary Energy Demand by 64% for the best scenario. The economic analysis depicted a significant influence of operating costs, and the electricity consumed in the processes is responsible for the largest share of expenses. The reuse water presented a cost ranging between US$ 1.08/m3 and US$ 1.80/m3. The systems with pretreatment by coprecipitation with Ca(OH)2 and CaCO3 and monoacids to adjust the pH of the final effluent showed to be more eco-efficient than the other options under analysis.

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Oil refineries are known for the large volume of water used in their processes, as well as the amount of wastewater generated at the end of the production chain. Due to strict environmental regulations, the recycling of water has now become a viable alternative for refineries. Among the many methods available to treat wastewater for reuse, the use of membranes in reverse osmosis systems stands out due to several economic and environmental benefits. However, these systems are vulnerable to contamination and deposition of microorganisms, mainly because of the feedwater quality. In this study, the microbial diversity of feedwater and reverse osmosis membranes was investigated using a combination of culture-dependent and culture-independent methods in order to characterize the microorganisms colonizing and deteriorating the membranes. In total, 37 bacterial isolates, 17 filamentous fungi and approximately 400 clones were obtained and analyzed. Among the bacterial genera identified, the most represented were Sphingobium, Acidovorax, Microbacterium, Rhizobium and Shinella. The results revealed genera that acted as candidate key players in initial biofilm formation in membrane systems, and provided important information concerning the microbial ecology of oligotrophic aquatic systems.

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BACKGROUND: In many companies, investigations of accidents still blame the victims without exploring deeper causes. Those investigations are reactive and have no learning potential. OBJECTIVE: This paper aims to debate the historical organizational aspects of a company whose policy was incubating an accident. METHODS: The empirical data are analyzed as part of a qualitative study of an accident that occurred in an oil refinery in Brazil in 2014. To investigate and analyse this case we used one-to-one and group interviews, participant observation, Collective Analyses of Work and a documentary review. The analysis was conducted on the basis of concepts of the Organizational Analysis of the event and the Model for Analysis and Prevention of Work Accidents. RESULTS: The accident had its origin in the interaction of social and organizational factors, among them being: excessively standardized culture, management tools and outcome indicators that give a false sense of safety, the decision to speed up the project, the change of operator to facilitate this outcome and performance management that encourages getting around the usual barriers. CONCLUSIONS: The superficial accident analysis conducted by the company that ignored human and organizational factors reinforces the traditional safety culture and favors the occurrence of new accidents.

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This paper comes out from the need to provide an improvement in the current oil refinery wastewater treatment plant (WWTP) aiming to generate water for reuse. The wastewater was pretreated and collected in the WWTP after the biological treatment unit (bio-disks) followed by sand filtration. Ozonation (ozone concentration from 3.0-60 mgO3 L-1), UV (power lamp from 15 to 95 W), H2O2 (carbon:H2O2 molar ratio of 1:1, 1:2, and 1:4), and two advanced oxidation processes (UV/O3 and UV/H2O2) were investigated aiming to reduce the wastewater organic matter and generate water with suitable characteristics for the reverse osmosis operation and subsequent industrial reuse. Even after the biological and filtration treatments, the oil refinery wastewater still presented an appreciable amount of recalcitrant organic matter (TOC of 12-19 mgC L-1) and silt density index (SDI) higher than 4, which is considered high for subsequent reverse osmosis due to membrane fouling risks. Experiments using non combined processes (O3, H2O2, and UV only) showed a low degree of mineralization after 60 min of reaction, although the pretreatment with ozone had promoted the oxidation of aromatic compounds originally found in the real matrix, which suggests the formation of recalcitrant compounds. When the combined processes were applied, a considerable increase in the TOC removal was observed (max of 95 % for UV/O3 process, 55 W, 60 mgO3 L-1), likely due the presence of higher amounts of reactive species, specially hydroxyl radicals, confirming the important role of these species on the photochemical degradation of the wastewater compounds. A zero-order kinetic model was fitted to the experimental data and the rate constant values (k, mgC L-1 h-1) ranged from 4.8 < k UV/O3 < 11 ([O3]0 = 30-60 mg L-1), and 8.6 < k UV/H2O2 < 11 (C:H2O2 from 1:1 to 1:4). The minimum and maximum electrical energy per order (E EO) required for 60 min of treatment were calculated as 5.4 and 81 Wh L-1, respectively, for UV/O3 (15 W, 60 mgO3 L-1) and UV/H2O2 (95 W, 1C:1H2O2). Good results in terms of water conditioning for reverse osmosis operation were obtained using UV/H2O2 process with initial molar ratio of 1 C:2 H2O2 (UV lamp 55 W) and 1 C:4 H2O2 (UV lamp 95 W), and total organic carbon (TOC) removals of 62 % (SDI15 = 1.8) and 74 % (SDI15 = 2.0) were achieved, respectively, after 60 min. The treated wastewater followed to the reverse osmosis system, which operated with an adequate flux of permeate, was very efficient to remove salt and generate a permeate water with the required quality for industrial reuse.

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This study evaluated pollution levels in water and sediments of Península de Paraguaná and related these levels with benthic macrofauna along a coastal area where the largest Venezuelan oil refineries have operated over the past 60 years. For this, the concentration of heavy metals, of hydrocarbon compounds and the community structure of the macrobenthos were examined at 20 sites distributed along 40 km of coastline for six consecutive years, which included windy and calm seasons. The spatial variability of organic and inorganic compounds showed considerably high coastal pollution along the study area, across both years and seasons. The southern sites, closest to the refineries, had consistently higher concentrations of heavy metals and organic compounds in water and sediments when compared to those in the north. The benthic community was dominated by polychaetes at all sites, seasons and years, and their abundance and distribution were significantly correlated with physical and chemical characteristics of the sediments. Sites close to the oil refineries were consistently dominated by families known to tolerate xenobiotics, such as Capitellidae and Spionidae. The results from this study highlight the importance of continuing long-term environmental monitoring programs to assess the impact of effluent discharge and spill events from the oil refineries that operate in the western coast of Paraguaná, Venezuela.

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The antioxidant responses in saplings of Tibouchina pulchra (a native tree from the Brazilian Atlantic Rainforest) exposed around an oil refinery in the city of Cubatão (SE Brazil), varied during the exchange of its power generation source, from boilers fueled with oil to a thermoelectric fueled with natural gas. The redox potential changed in response to an interaction of air pollution and meteorological parameters, indicating that the pro-oxidant/antioxidant balance was not reached after the exchange of the power generation system. The gain in environmental quality in the region was not achieved as expected due the technological modernization, at least relative to oxidative stressors. These conclusions were based on results of analyses of enzymatic antioxidants: superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR); non-enzymatic antioxidants: reduced, oxidized and total ascorbic acid (AsA, DHA, totAA) and glutathione (GSH, GSSG, totG), their redox state (AsA/totAA and GSH/totG) and an indicator of lipid peroxidation (MDA). We also applied exploratory multivariate statistics in order to verify if the temporal sequence of changes in the plant redox capacity coincided with changes in the profile of air pollution, climatic conditions or with their interactions and if the environmental benefits that would supposedly be promoted by the mentioned exchange of power generation system were achieved in the region.

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We assessed the level of atmospheric contamination by S, N and metals before, during and after the installation of a new thermoelectric plant that provides power to an oil refinery in Cubatão, SE Brazil. We measured the foliar accumulation in Lolium multiflorum "Lema" with the aim of evaluating risks to the Atlantic Rainforest that grows in the region. Al, Co, Cr, Cu, K, N, Ni, S, V and Zn were appropriate markers of the new air contamination profile associated with the modern technology. With the exception of V, the leaf contents of these elements significantly increased between the pre-operation to post-operation phases (Al, Co, N, K, S), or only during the transition phase (Zn, Cu, Cr, Ni), and returned to the previous levels after the total shutdown of the old system. Therefore, the expected environmental gain was not achieved with the installation of the new technology.

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Os acidentes de trabalho nas refinarias de petróleo se destacam por liderar vários indicadores de incidência e mortalidade dentro da indústria de transformação no Brasil. A abordagem das análises dos acidentes tem evoluído desde uma concepção do erro humano até as relações inter organizacionais. As empresas continuam usando abordagens tradicionais na investigação de acidentes que não ajudam na prevenção eficaz dos mesmos. Os estudos aprofundados em acidentes do setor que mostrem a relação de fatores organizacionais são escassos. Em Setembro de 2014, em uma refinaria da região sudeste de Brasil, seis trabalhadores sofreram queimaduras múltiplas como consequência de um incêndio por vazamento de gás liquefeito de petróleo (GLP) que entrou em contato com uma fonte de ignição. Uma das vítimas faleceu dois meses depois. Objetivo - Contribuir para a difusão de uma abordagem organizacional para analisar este acidente de trabalho ultrapassando o erro humano, as causas técnicas e as perspectivas indicadas pelas normas padrão. Método - Os dados empíricos são baseados em um estudo qualitativo de um acidente de trabalho. Para realizar este estudo de caso usamos entrevistas, Análise Coletiva de Trabalho, observação participante e análise de documentos. Em seguida, realizamos uma Análise Organizacional do Evento (AOE) e aplicamos o Modelo de Análise e Prevenção de Acidentes (MAPA).

Work accidents in oil refineries stand out for leading several incidence and mortality indicators within the manufacturing industry in Brazil. The approach of the analysis of accidents has evolved from a conception of human error to the interorganizational relations. Companies continue to use traditional approaches in the investigation of accidents that do not help in effective prevention. In-depth studies on industry accidents that show the relationship of organizational factors are scarce. On September 2014, in a refinery in the south-eastern region of Brazil, six workers suffered burns multiples as a result of a fire by pouring Liquefied Petroleum Gas (LPG) which came into contact with an ignition source. One of the victims died two months later. Aim - To contribute to the diffusion of an organizational approach to analyzing this work accident beyond human error, technical causes and the prospects indicated by the standard rules. Method - The empirical data are based on a qualitative study of a work accident. This case study used interviews, Collective Labour Analysis, participant observation and document analysis. Then we conducted an event organizational analysis and we applied the Model Analysis and Accident Prevention (MAPA.

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In this work, the ability of the diffusive gradients in thin films technique (DGT) was evaluated for monitoring the concentrations, and estimating the availability, of metals at a northeastern Brazilian coastal area under the influence of oil production. Three sites with an average distance between 0m (EM-1), 100 m (EM-2), and 1,000 m (EM-3) of a submarine outfall-I (Guamaré-RN, Brazil) and another site (GA-1) with an average distance of 12,000 m east of Outfall I, near the city of Galinhos, were studied. DGT units were deployed at the same sites in three campaigns from July, 2010 to June, 2011. Effects on the accuracy of analytical results regarding the deployment time, gel porosity, and thickness were evaluated. There was no difference between the measurements obtained with two sets of DGT devices, those assembled with open or restrictive pore gel, respectively, showing that organic metallic species are not present near the submarine outlet. After 21 day deployments in a region (near Submarine Outfall I) that receives produced waters that have been treated, there was evidence of biofilm formation on DGT membranes. However, it was demonstrated that the biofilm interference with DGT measurements was negligible. Data found in this work show that total concentrations of Cd, Cu, Pb, Ni, and Zn in seawater samples collected at sites GA-1 and EM-1 in two campaigns were below 0.33, 1.67, 0.47, 0.70, 2.86 ng mL(-1) respectively. For the first time, labile levels of Cd, Cu, Pb, Ni, and Zn in an area under the influence of oil production were determined. DGT measurements allowed the verification of the effects of temporal variation on levels of Zn and Ni. There were no effects of spatial variations on levels of Cd, Cu, Ni, Pb, and Zn at the four studied sites, suggesting no contamination of these metals at the northeastern Brazilian coastal area investigated in this work.

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A magnitude dos problemas socioambientais relacionados à urbanização, industrialização e esgotamento de recursos naturais tem impacto crescente sobre a saúde e o ambiente. Paradoxalmente, os padrões de consumo demandam a ampliação da produção industrial, baseada na exploração de recursos não renováveis, cujos riscos tecnológicos, particularmente os da indústria petroquímica, impõem dificuldades reais às medidas de controle e vigilância à saúde. O refino de petróleo é uma atividade potencialmente danosa ao ambiente e à saúde humana, particularmente aos trabalhadores. Esse estudo objetivou caracterizar os cenários de risco para a saúde ambiental decorrentes da instalação de uma refinaria de petróleo na Região Metropolitana de Recife (Pernambuco). Com base em dados secundários e referências da literatura, construiu-se uma matriz de reprodução social para contextualizar os problemas nas dimensões biológica, da consciência e conduta, econômica, política e ecológica, permitindo presumir riscos, com vista a subsidiar o desenvolvimento e a organização das ações de vigilância em saúde no Estado, articuladas intersetorialmente, com participação social, capazes de intervir sobre os riscos e evitar o adoecimento dos trabalhadores e da população nesse território.

The magnitude of the environmental and social problems due to urbanization, industrialization and exhaustion of natural resources has shown an increase in the impact on health and environment. Paradoxically, the consumption patterns demand for the expansion in the industrial production based on the exploitation of the non-renewable resources, which technological risks, especially from the petrochemical industry, have put difficulties on the risk control and health surveillance. The petroleum refining is an activity potentially damageable to the environment and human health, particularly to workers. The main objective of this study was to characterize the scenarios of risk to environmental health due to an oil refinery installation in the Metropolitan Region of Recife (Pernambuco). Based on secondary data and literature review, a Social Reproduction Matrix was made contextualizing the problems in the biological, consciousness and conduct, economic, policy and ecological dimensions, enabling to presume the risks to support the health surveillance development and organization in the state, with intersectoriality, social participation, and able to intervene on risks and prevent diseases among the workers and people in the territory.

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The aim of this study was to compare the 7-day Ceriodaphnia dubia survival and reproduction test with a 4 day test to evaluate the toxicity of oil refinery effluents. Both shown identical NOECs with three of 6 tested samples. With one of the tested samples, the 4-day NOEC was one tested-concentration lower, and with the remaining two samples, it was one tested-concentration higher than those obtained using the 7-day protocol. Then results suggested that 4 and 7-day protocols were comparable to detect toxic effects.

O objetivo do presente estudo foi comparar os protocolos de sobrevivência e reprodução de Ceriodaphnia dubia com 7 e 4 dias de duração, avaliando a toxicidade de amostras de efluentes de refinaria de petróleo. Ambos os protocolos apresentaram NOECs idênticos para 3 das 6 amostras testadas. Com uma das amostras o NOEC no ensaio de 4 dias ficou numa concentração testada menor, e nas duas amostras restantes ele ficou numa concentração testada maior do que os NOECs obtidos no ensaio de 7 dias. Esses resultados sugerem que os protocolos de ensaio com 4 e 7 dias são comparáveis quanto a sensibilidade para detectar o efeito tóxico crônico de efluentes de refinaria de petróleo.