Avaliação de diferentes processos oxidativos avançados no tratamento de resíduos de petróleo

The petroleum industry deals with problems which are difficult to solve because of their relation to environmental issues. This is because amounts of residue are generated which vary in type and danger level. The soil contamination by non aqueous liquid phase mixtures, specifically hydrocarbon petroleum has been a reason for great concern, mainly the aromatic and polycyclic aromatic, which present risk to human health due to its carcinogenic and mutagenic character. The Advanced Oxidative Processes (AOP) are efficient technologies for destruction of organic compounds of difficult degradation and, often, they are present in low concentrations. They can be considered clean technologies, because there is no formation of solid by-products or the transfer of pollutor phases. This work focuses on the study of the degradation of petroleum industrial waste, by Advanced Oxidation Processes. Treatments tackling petroleum residues, contaminated soil, and water occurring in the production of petroleum reached the following Polycyclic Aromatic Hydrocarbons (PAH) degradation levels: solid residues 100% in 96 treatment hours; water residue - 100% in 6 treatment hours; soil contamination (COT degradation) - 50.3% in 12 treatment hours. AOP were effective in dealing with petroleum residues thus revealing themselves to be a promising treatment alternative

Avaliação da eficiência de lagoas de estabilização no tratamento de resíduos esgotados de fossas sépticas

Because of disability in public policy development in mind to attend issues of sanitation in the municipalities, companies known as "clean-blue" appeared proposing to solve a simple collection and management of wastewater produced in single or multifamily residences, commercial, hospitals, etc. In the case of an activity in which there are no worries about the fate of sewage, emerged some doubts about the degree of health and environmental safety in these companies. Traditionally, most of them makes the provision of waste depleted soil or wetland, open, usually located on the outskirts of cities (MENESES, 2001). In turn, the sludge from septic tanks exhausted, provided no technical criteria - in the soil, rivers and as an agricultural fertilizer put in risk the health of the population and environmental quality. This work was entered in the search network 5 of the Notice of the Research Program in Sanitation - PROSAB-5, aimed to study the theme 'Characterization and study of alternative ways of treating sludge from septic tanks in the city of Natal, RN', proposing to evaluate the performance of the use of stabilization ponds as a system to handle waste from septic tanks exhausted. A series of lakes studied belong to one of the largest clean-pit of Natal, consisting of two anaerobic ponds, one facultative and maturation, and a tank disinfection, the wastewater being released in the Potengi River. Samples were collected between the months of October 2007 to October 2008, at six points previously defined and judged as more appropriate to what is proposed study. The analysis results in field and laboratory showed the most significant removal of COD (88.93%), total suspended solids (94.87%), organic nitrogen (66.87%) and thermotolerant coliforms (99.88%). Some results have not reached the expected because the system under study had operating problems that have undermined the efficiency of the reactors

Otimização do sistema de supervisão e controle de uma planta de tratamento de resíduos utilizando plasma

A major and growing problems faced by modern society is the high production of waste and related effects they produce, such as environmental degradation and pollution of various ecosystems, with direct effects on quality of life. The thermal treatment technologies have been widely used in the treatment of these wastes and thermal plasma is gaining importance in processing blanketing. This work is focused on developing an optimized system of supervision and control applied to a processing plant and petrochemical waste effluents using thermal plasma. The system is basically composed of a inductive plasma torch reactors washing system / exhaust gases and RF power used to generate plasma. The process of supervision and control of the plant is of paramount importance in the development of the ultimate goal. For this reason, various subsidies were created in the search for greater efficiency in the process, generating events, graphics / distribution and storage of data for each subsystem of the plant, process execution, control and 3D visualization of each subsystem of the plant between others. A communication platform between the virtual 3D plant architecture and a real control structure (hardware) was created. The goal is to use the concepts of mixed reality and develop strategies for different types of controls that allow manipulating 3D plant without restrictions and schedules, optimize the actual process. Studies have shown that one of the best ways to implement the control of generation inductively coupled plasma techniques is to use intelligent control, both for their efficiency in the results is low for its implementation, without requiring a specific model. The control strategy using Fuzzy Logic (Fuzzy-PI) was developed and implemented, and the results showed satisfactory condition on response time and viability

Caracterização dos resíduos esgotados de sistemas de tratamento individual de esgotos de Natal

In Natal still dominates the use of individual disposal systems for domestic sewage, once only 29% of the city has a sewarage system. Wastes that are accumulated in these individual treatment systems should be exhausted periodically, service provided by collector entrepreneurs. Some of these companies causing major damage to the environment. In Natal, only two companies have their own septage (RESTI) treatment system, which were designed with parameters from domestic sewage generating strain and inefficient systems. Therefore, the characterization becomes essential as a source of parameters for their design. Thus, this work presents the physical-chemical and microbiological characterization of waste pumped from individual sewage treatment systems. Samples collections were made weekly from 5 different trucks at the reception point on the treatment plant on the point of the preliminary treatment. From each truck it was taken 5 samples during the discharge in order to make a composite sample. Afterwards, samples were carried out to laboratory and analyses for determination of temperature, pH, conductivity, BOD, COD, nitrogen (ammonia e organic), alkalinity, oils, phosphorus, solids, faecal coliforms and helminth egg. The results were treated as a single database, and ranked according to its generating source (multi and single house, lodging, health, services and / or food), area of origin (metropolitan, south and north) and type of system (cesspits, septic tank and / or sink). Through these data it was possible to verify that the type of system adopted by most in Natal and the metropolitan region is cesspit, besides to confirm the difference between the septage of areas with a population have different social and economical characteristics. It was found that the septage have higher concentrations than domestic sewage, except for thermotolerant coliforms that showed concentrations of 1,38E+07. Among the parameters studied, is the median values identified for COD (3,549 mg / L), BOD (973mg / L) and total solids (3.557mg / L). The volatile fraction constitutes about 70% of the total solids of the septage. For helminths has been a median of 7 eggs/L. In general, the characteristics of the waste followed the variability found in the literature reviewed for all variables, showing high amplitudes

Analise SWOT do gerenciamento de resíduos do coco verde em duas agroindústrias do estado do Rio Grande do Norte

In the current conjuncture, the environmental factor has been changing the position of companies that are practicing or minimally adopting environmental management. Such tool has been used by companies to face the problems caused by solid waste, in particular green coconut waste, which is constantly among the material discarded by society (companies/ consumer). It is a typical tropical fruit whose fresh water is very benefic for human health, and its popularization has caused a progressive increase of its consumption. Following this stream of thought, this present work came up with an analysis of strengths, weaknesses, threats, and opportunities SWOT analysis on green coconut solid waste management at two agribusiness companies in the state of Rio Grande do Norte (RN), Brazil, aiming to know the challenges and the potentials of this kind of waste. According to the approach of the problem, this work fits a descriptive, exploratory, and qualitative research. The data collection was obtained by a questionnaire and a structured interview, in order to evaluate the strategic posture of agribusiness companies through SWOT analysis, which is an English acronym for Strengths, Weaknesses, Opportunities and Threats. The SWOT analysis is an effective tool to analyze the internal and external environment of an organization. This tool contributes to locate the company at the environment in question and when well applied it enables the detection of mistakes, the strengthening of correct procedures, the avoidance of threats, and the bet on opportunities. The studied agribusiness industries have very similar profiles, such as a long business life span, and a strategy that extends the useful life of the fruit, by using its waste for the manufacturing of new subproducts. In both, the daily quantity of waste resulted of this process reaches approximately 20 thousand units of the fruit in high season, being necessary a focus directed at use and/or treatment of these waste. Further to SWOT analysis, it was ascertained that the agribusiness company A works through a defensive marketing strategy and acts vulnerably, in other words, unable of acting before this market segment, for it has decided to stop using the waste due to a lack of equipment and technology. On the other hand, the agribusiness company B has incorporated an offensive marketing strategy because even not possessing equipments, technology, and appropriated internal installations, it still insists on use and benefits of green coconut waste in its agribusiness. Thus, it is considered that the potential of green coconut waste management for the production of several subproducts reduces the impacts produced by inappropriate placement and generates profits in a short, medium and long term. Such profits being tangible and intangible, as the interest for sustainability actions is not only a matter of obtaining return on capital, but it is an important question in order to move on into business, since it is not enough to have quality on products and process nowadays. It is necessary to establish socio-environmental practices aiming the image of the company as the prevailing role on consumers buying decision

Desenvolvimento de um sistema de automação para uma planta de inertização de resíduos por plasma

The traditional processes for treatment of hazardous waste are questionable for it generates other wastes that adversely affect people s health. As an attempt to minimize these problems, it was developed a system for treatment of hazardous waste by thermal plasma, a more appropriate technology since it produces high temperatures, preventing the formation of toxic pollutants to human beings. The present work brings out a solution of automation for this plant. The system has local and remote monitoring resources to ensure the operators security as well as the process itself. A special attention was given to the control of the main reactor temperature of the plant as it is the place where the main processing occurs and because it presents a complex mathematical model. To this, it was employed cascaded controls based on Fuzzy logic. A process computer, with a particular man-machine interface (MMI), provides information and controls of the plant to the operator, including by Internet. A compact PLC module is in charge of the central element of management automation and plant control which receives information from sensors, and sends it to the MMI

Panorama dos resíduos sólidos urbanos nos municípios de pequeno porte do Brasil

The panorama of Urban Solid Waste (USW) in Brazil, in general lacks information, given the immensity of the country. However, it is from available data that the public executives should define the USW management. To contribute to the choice of a model for the management of USW in small municipalities, this study reviews the related literature, showing an overview of the final disposal of USW in small municipalities. Several data and researches are discussed, concluding that the available data, despite being provided by the public managers, who often attenuate the problem, should be considered for the proposition of policies to encourage the waste treatment

Gestão dos resíduos sólidos no Brasil e seus rebatimentos em Natal, Brasil

O artigo apresenta a gestão dos resíduos sólidos no Brasil e seus rebatimentos na cidade de Natal/RN, verificando seus aspectos ambientais, econômicos e sociais. O fracasso da coleta seletiva revelado nos baixos índices de recuperação dos materiais; a baixa relevância da inclusão socioeconômica dos catadores que participam do programa assistencialista oficial; a inexistência de estratégias oficiais para que se minimize a quantidade de resíduos que se gera cada dia e o aumento exagerado dos gastos públicos, sobretudo com o tratamento dos resíduos no aterro sanitário, demonstram que a gestão de resíduos em Natal, conforme parâmentros da Política Nacional de Residuos Sólidos, objetiva o controle destes na cidade e a consolida- ção do tratamento finalista através do envio da quase totalidade dos resíduos coletados ao aterro sanitário

Caracterização de água de lavagem de filtros em estações de tratamento de água de filtração direta

The water supply and treatment is considered as a great benefit considering that, if done efficiently, provides public health. However, considering the WTP (Water Treatment Plant) is an industry, with its inputs and waste generation, they must be constantly evaluated and monitored to verify the best and most appropriate way to process and dispose their waste, minimizing therefore the potential impacts to the environment. By volume, the most significant waste is the rapid filter backwash water. It is very common the disposal of this waste without treatment in water sources, which are used, for the most part, as a water supply source of a downstream population. This study evaluated quantitative and qualitative parameters in filter backwash water in three WTP - Itaitinga, Maranguape and Pacatuba, located in Ceará State, northeast of Brazil. It was found that the Maranguape WTP, in terms of treatment capacity, is the larger. The Itaitinga WTP is the one that consumes more water during filters washing. The Pacatuba WTP exhibited higher concentration of total suspended and settleable solids, COD and aluminum in the filters backwash water. It is noteworthy that the settleable solids and total suspended solids in all three WTP are above the effluent discharge standard recommended by Resolution 154/2002 of SEMACE (State Superintendent of Environment of Ceará). It was concluded that the filter backwash water from the study WTP exceeded the allowed values for legislation to be disposed directly into surface water bodies. It is suggested as an alternative to treat and recycle the filter backwashing water the construction of sludge settling ponds.

Avaliação da biodegradabilidade de petróleo utilizando microrganismos isolados do estuário do Rio Potengi (RN)

The oil activity in the Rio Grande do Norte State (RN) is a permanent threat to coastal ecosystems, particularly mangroves, with the possibility of oil spills. In this context, the objective of this study was to evaluate the potential resistance of the mangrove environment of a possible spill. Were selected and isolated microorganisms degrading oil by the technique of enrichment cultures and formation of a bacterial consortium. The kinetic study of the consortium was held in rotary incubator shaken at 150 rpm and 30° C. Samples were taken at intervals of 4 hours for analysis of cell concentration and surface tension. The biodegradation was monitored using two methods of respirometry: manometric (OxiTop-C ®) and conductivimetry, where the biodegradation of oil was estimated indirectly by oxygen consumption and CO2 production, respectively. Furthermore, it was used a full 2² factorial design with triplicate at central point to the runs that used the conductivimetric methodology.. The technique of enrichment cultures allowed to obtain thirteen bacterial strains. Kinetic study of the consortium, we can showed the absence of the lag phase, reaching a maximum cell concentration of 2.55 g / L at 16 h of cultivation and a reduction on surface tension. When we adopted the methodology of OxiTop-C was detected a band indicating biodegradability (1% oil v/v), however when we used the conductivimetry methodology did not observe any band that would indicate effective biodegradation. By monitoring a process of biodegradation is necessary to observe the methodology will be adopted to evaluate the biodegradation process, since for the same conditions adopted different methodologies can produce different results. The oil-degrading isolates from soils of the mangrove estuary Potengi / RN are largely to be used in bioremediation strategies of these places, in the case of a possible oil spill, or it can be used in the treatment of waste oil generated in saline environments, since they are optimized the conditions of the tests so that the efficiency of biodegradation reach the minimum level suggested by the standarts

Projeto de um Transformador utilizado em uma Planta de Plasma

This work discusses the design of a transformer used in a plant plasma. This plant, which is being developed in UFRN, will be used in the treatment of waste. It consists basically of a radio frequency power supply and a inductive plasma torch. The transformer operates at the nominal frequency of 400 kHz, with 50 kW, allowing the adaptation of impedance between the power supply and torch. To develop the project, a study was done on the fabrication technologies and physical effects on the frequency of operation. This was followed by the modeling of this transformer. Finally, simulations and tests were conducted to validate the design

Controle de Temperatura do Sistema de Refrigeração a água de uma tocha plasmática Indutiva Utilizando Lógica fuzzy

Este projeto propõe desenvolver e implementar um controlador para o sistema de refrigeração da tocha indutiva a plasma térmico. Este processo é feito a partir da medição da temperatura através de um sensor do sistema de refrigeração. O sinal produzido será enviado para uma entrada analógica do microcontrolador da família PIC, que utilizando os conceitos de lógica fuzzy, controla a velocidade de um motor bomba. Este é responsável por diminuir ou aumentar o fluxo circulante de água que passa pela bobina, pelo corpo da tocha e pelo flange de fixação, deixando-os na temperatura desejada. A velocidade desta bomba será controlada por um inversor de frequência. O microcontrolador, também, acionará um ventilador caso exceda a temperatura de referência. A proposta inicial foi o desenvolvimento do controle da temperatura da bobina de uma tocha indutiva a plasma, mas com algumas adequações, foi possível também aplicar no corpo da tocha. Essa tocha será utilizada em uma planta de tratamento de resíduos industriais e efluentes petroquímicos. O controle proposto visa garantir as condições físicas necessárias para tocha de plasma, mantendo a temperatura da água em um determinado nível que permita o resfriamento sem comprometer, no entanto, o rendimento do sistema. No projeto será utilizada uma tocha de plasma com acoplamento indutivo (ICPT), por ter a vantagem de não possuir eletrodos metálicos internos sendo erodidos pelo jato de plasma, evitando uma possível contaminação, e também devido à possibilidade do reaproveitamento energético através da cogeração de energia. O desenvolvimento da tecnologia a plasma na indústria de tratamento de resíduos vem obtendo bons resultados. Aplicações com essa tecnologia têm se tornado cada vez mais importantes por reduzir, em muitos casos, a produção de resíduos e o consumo de energia em vários processos industriais

Caracterização do conteúdo de fossas e tanques sépticos na cidade de Natal

Only 32% of the population of Natal is attended by sewage, while the remaining population use pits and septic tanks. The characterization of the contents of septic tanks and pits contributes to the performance of such system and may guide the decision on treatment of these contents. The main of this research is to characterize the contents of interior residential pits and septic tanks in the greater Natal, with the following specific goals: to develop and manufacture a sampler capable of collecting a representative sample of the entire column (the surface scum, the clarified liquid and sludge bottom); to compare the contents of the tanks with the pits; to compare the contents of the septage from vacuum trucks; to relate the composition content with socioeconomic characteristics of households; to compare the content in both chambers of the septic tanks in series; to assess the situation of the content before and six months after the cleanness; and ultimately propose a pilot scale plant for treatment of septage. Once the sampler was developed, samples were collected within 14 septic tanks and 10 pits in many districts of Natal. Medians of the 24 systems were obtained: temperature, pH, conductivity, oil and grease, total solids, total suspended solids and sediments of 28.0 °C, 6.95; 882 mS/cm, 75.2 mg/L; 10,169 mg/L, 6,509 mg/L and 175 mL/L respectively; 111.0 mgN/L for ammonia, 130.5 mgN/ L for organic nitrogen, 0.2 mgN/L for nitrite, 0.4 mg/L for nitrate; 8935 mgO2/L for COD, 29.2 mgP/L for total phosphorus, thermotolerant coliforms from 9.95 E +06 CFU/100mL helminth eggs and 9.2 eggs/L with a maximum concentration of 688 eggs/L and minimum of 0 eggs/L. Medians of organic nitrogen and TKN were significantly different between groups of tanks and pits. The systems with cleanness gap from 11 and 20 years presented the higher concentrations for most variables. The effluent from the toilets and bathrooms participate more effectively in contributing fractions of solids, alkalinity, nitrogen, COD, total phosphorus, thermotolerant coliforms and helminth eggs. The systems used by socioeconomics class with income from R$ 3,700.00 to R$ 7,600.00, presented higher concentrations for COD, nitrogen, solids and helminth eggs. The first of the two chambers had always presented higher concentrations over the second compartment. The analysis of variance for most variables, showed that the values of septic tanks, pits and septage from vacuum trucks belong to the same group. In the samples taken after cleanness, the median of pH and temperature increased, while alkalinity, COD, organic nitrogen, total phosphorus, ammonia and helminth eggs decreased. The oils and greases and thermotolerant coliforms had slightly varied due to the continuous release of sewage into the systems that maintained their steady state concentrations.

Química em cena: uma proposta para formação inicial de professores de química

In educational observed difficulty in train teachers to meet the medium and higher education needs, and one reason for this is the different experiences in the training of educators in relation to those found in the classroom. So often arise criticisms related to relevance and efficiency of degree courses, as regards the performance of its natural mission, which weakens the teacher training. Thus, improving the quality of education is very dependent on the initiatives of teachers, creating teaching alternatives to strengthen their performance in school. From this reflection, it is concluded that teacher training needs new educational proposals that qualify, and so can promote the formation of his students more adequately. Among the educational proposals as alternatives to initial teacher training may use the scientific theater (TC). Considering this possibility, this work has been proposed as investigate and discuss the influence of TC combined with experimentation in the initial training of future teachers in Chemistry who participate in the Groups Fanatics chemistry Theatre (UERN) and Chemistry on Stage (UFRN). Therefore, there was, in a first stage, theatrical essays based on the theater of the oppressed, and written dramaturgical scripts, a collaborative proposal. To incorporate experimentation in chemistry to theater rehearsals, there was a systematic literature search and after content analysis, were selected categories, materials and reagents easily accessible, easy procedures and implementation with low risk of accidents and easy care chemical waste. In the second part we identified: a) the beliefs of student teachers in the use of TC ally trial for initial training of chemistry teachers; b) the influence of TC ally to trial on learning of chemical concepts of high school students who attended the shows; c) the reasons for using or not TC ally to trial by chemistry teachers who participated in the TC group and currently work in the classroom. In this study, questionnaires and interviews were used, compounds, respectively, by a Likert scale and open questions. Quantitative data were analyzed by classical statistics the media, using as centrality measures the average, the concordance argument and the average deviation. Qualitative data were discussed according to content analysis, with categories that emerged from reading the answers. These analyzes concluded that the licensees have a positive view on the use of scientific theater for disclosure of the chemical for use in the learning of chemical concepts, pedagogical and disciplinary knowledge, and to form promotion strategy for research and extension at the University. They credit improvements in their initial training on the use of scientific theater combined with experimentation. The TC provides motivation for the construction of conceptual thinking in an informal way of chemical communication, allowing the student to expand their knowledge, not only favoring the phenomenological approach, but also the construction of chemical knowledge and the internalization of scientific concepts.

Avaliação da biodegradabilidade de petróleo utilizando microrganismos isolados do estuário do Rio Potengi (RN)

The oil activity in the Rio Grande do Norte State (RN) is a permanent threat to coastal ecosystems, particularly mangroves, with the possibility of oil spills. In this context, the objective of this study was to evaluate the potential resistance of the mangrove environment of a possible spill. Were selected and isolated microorganisms degrading oil by the technique of enrichment cultures and formation of a bacterial consortium. The kinetic study of the consortium was held in rotary incubator shaken at 150 rpm and 30° C. Samples were taken at intervals of 4 hours for analysis of cell concentration and surface tension. The biodegradation was monitored using two methods of respirometry: manometric (OxiTop-C ®) and conductivimetry, where the biodegradation of oil was estimated indirectly by oxygen consumption and CO2 production, respectively. Furthermore, it was used a full 2² factorial design with triplicate at central point to the runs that used the conductivimetric methodology.. The technique of enrichment cultures allowed to obtain thirteen bacterial strains. Kinetic study of the consortium, we can showed the absence of the lag phase, reaching a maximum cell concentration of 2.55 g / L at 16 h of cultivation and a reduction on surface tension. When we adopted the methodology of OxiTop-C was detected a band indicating biodegradability (1% oil v/v), however when we used the conductivimetry methodology did not observe any band that would indicate effective biodegradation. By monitoring a process of biodegradation is necessary to observe the methodology will be adopted to evaluate the biodegradation process, since for the same conditions adopted different methodologies can produce different results. The oil-degrading isolates from soils of the mangrove estuary Potengi / RN are largely to be used in bioremediation strategies of these places, in the case of a possible oil spill, or it can be used in the treatment of waste oil generated in saline environments, since they are optimized the conditions of the tests so that the efficiency of biodegradation reach the minimum level suggested by the standarts