Revista Eletrônica em Gestão, Educação e Tecnologia Ambiental

Batch biodigesters efficiency in anaerobic biodigestion waste of swine

2024-02-01T10:04:50-03:00

A expansão da suinocultura consolidou esta atividade entre as que mais impactam negativamente o meio ambiente. Os grandes volumes de águas residuais geradas em pequenas unidades, aliados à falta de tecnologias e incentivos para tratar esses resíduos, tornam este problema ainda mais grave. Objetivou-se avaliar a remoção dos parâmetros Demanda Química de Oxigênio (DQO), Demanda Bioquímica de Oxigênio (DBO), Sólidos Fixos (FS) e Sólidos Voláteis (SV), na digestão anaeróbia de dejetos suínos utilizando biodigestores de fluxo descontínuo em escala piloto, sob o influência de diferentes temperaturas ambientes durante o período de um ano (365 dias). O delineamento estatístico foi em blocos casualizados, com oito tratamentos e três repetições, sendo cada tratamento um ciclo com tempo de retenção hidráulica (TRH) de 40 dias. Houve dois ciclos para cada estação, amostras de águas residuais brutas foram coletadas, e cada biodigestor foi tratado. Diferenças significativas entre os ciclos avaliados. As eficiências finais encontradas para DBO foram de 81,03% (ciclo 5) e 14,86% (ciclo 3). Para DQO foram 76,07% (ciclo 5) e 17,79% (ciclo 1). Para FS 58,58% (ciclo 3) e 15,97% (ciclo 6). Para VS foram 86,68% (ciclo 7) e 24,75% (ciclo 3). A eficiência média em oito ciclos foi maior para DQO. Concluiu-se que os biodigestores anaeróbios em batelada em escala piloto demonstraram ser eficazes no tratamento de dejetos de suínos. Porém, sua eficiência depende da temperatura e do TRH adotado. Para SV foram 86,68% (ciclo 7) e 24,75% (ciclo 3). A eficiência média em oito ciclos foi maior para DQO. Concluiu-se que os biodigestores anaeróbios em batelada em escala piloto demonstraram ser eficazes no tratamento de dejetos de suínos. Porém, sua eficiência depende da temperatura e do TRH adotado. Para VS foram 86,68% (ciclo 7) e 24,75% (ciclo 3). A eficiência média em oito ciclos foi maior para DQO. Concluiu-se que os biodigestores anaeróbios em batelada em escala piloto demonstraram ser eficazes no tratamento de dejetos de suínos. Porém, sua eficiência depende da temperatura e do TRH adotado.

Biodegradation and biotransformation of petroleum hydrocarbons: progress, prospects, and challenges

2023-07-14T16:52:06-03:00

Oil is considered the main source of energy, being essential for the realization of various industrial activities. However, it is detrimental to the environment, since in addition to the release of polluting gases during combustion, its exploitation involves risks of water contamination, through leaks. Petroleum hydrocarbon pollutants are part of the recalcitrant compounds and their elimination from the environment causes enormous ecological impacts. The restoration of these environments is not a trivial challenge, as natural degradation, without anthropogenic involvement, depends on the nature, composition, physical and chemical properties of these compounds. Thus, bioremediation appears as alternative in the biodegradation process through the addition of microorganisms, nutrients or other substances that cause and accelerate decontamination. The advantages of these methods involve efficiency and low cost, when compared to other technologies. This work gathers knowledge about the perspectives of application of bioremediation systems in the recovery of environments polluted by petroleum hydrocarbons, discussing progress, perspectives and challenges.

Antibiofilm and antibacterial effects of essential oils extracted from plants on Staphylococcus aureus

2023-07-14T16:52:10-03:00

Staphylococcus aureus is a major pathogen among bacterial infections, also having the ability to produce biofilm, thus becoming tolerant and resistant to antibiotics and immune responses. Essential oil extracted from plants has shown broad-spectrum antibacterial and antibiofilm activities against bacteria. In this study it was evaluated whether rosemary, clove and cinnamon essential oil exert antibacterial and antibiofilm activities against S. aureus in vitro. The essential oils were purchased and their chemical composition was identified by gas chromatography and mass spectrometry (GC-MS). Antibiofilm and antibacterial effects were assessed by the 96-well microtiter plate adhesion assay. The highest antimicrobial and antibiofilm activity were observed with 3% and 6% cinnamon essential oil while the essential oil of clove and rosemary did not show satisfactory results. These results support new antimicrobial therapies against S. aureus infections and biofilm formation, using cinnamon essential oil, thus contributing to both human and veterinary medicines.

Assessment of the economic sustainability of water capture from surface and underground water sources to supply urban areas

2023-07-14T16:52:03-03:00

Analyze the implications of the configuration of the Sectors that make up the Water Supply Systems (WSSs) in the municipality of Belém, capital of the state of Pará, on their economic sustainability. The research was developed in three stages. The first stage consisted of identifying and collecting information regarding the WSSs operated by Companhia de Saneamento do Pará – COSANPA. In the second stage, operational and commercial indicators were determined for both Sectors selected as the most suitable for comparison, in this case the 12th Sector and the 23rd Sector. In the last stage, an analysis of the economic sustainability of selected Sectors was performed. It was verified that 04 of the 39 WSSs collect raw water from a surface water source, while the other 35 WSSs use deep wells (about 270 meters deep) to collect water from Pirabas artesian aquifer. In addition, operational efficiency indicators were calculated, such as the “Distribution Losses Index” – 69,08% (12th Sector) and 72,67% (23rd Sector), and economic sustainability indicators, such as the “Total Expense with the Services per Billed Cubic Meter” – R$1,92/m³ (12th Sector) and R$1,29/m³ (23rd Sector). In conclusion, due to the classification of both studied Sectors, regarding operational efficiency and economic sustainability, as inefficient and partially sustainable respectively, it is recommended to improve the operational and comercial management of the regional concessionaire, in compliance with the premises of Law No. 14.026/2020 and to ensure the economic and financial balance of the service provider.

Solid Waste Management in Small Municipalities: When and How to Discuss a New Fee?

2023-07-31T14:14:54-03:00

Solid waste management (SWM) at the municipal level is challenging for developing countries. Typically, the service runs at an economic loss and is of low quality, with high environmental impacts. The research aimed to evaluate how budgetary and public policies may affect the quality of solid waste management in small municipalities from underdeveloped countries. This study reports the economic impact of the operational routine, legislation, taxes, and total SWM costs in a small municipality of Brazil (36,000 inhabitants). Eleven types of waste and related services were evaluated from 2017 to 2020. Results show that the SWM budget would have to increase from the current 3.64% of the annual city budget to 7.48% to supply this management's financial needs under a future scenario of full legislative compliance. The costs required for this compliance would increase expenses from US$ 29.09 to US$ 46.05 per inhabitant per year. Alternatives to solve or alleviate the problem are efficiency's continuous improvement, new types of fundraising, inter-municipal cooperation, and increased inspection, especially related to establishing the legal responsibilities for waste generators. A new fee could also be discussed since this municipality (as well as more than half of Brazilian cities) has no specific charge for SWM. A US$ 9.40 per inhabitant/year charge would cover the operational costs related to domestic solid waste.

Diagnosis of environmental impacts using the SAIA: A case study in the Brígida irrigation project, in the town of Orocó/PE, Brazil

2023-12-11T12:00:22-03:00

Environmental impact assessment (EIA) is a decision-making tool and in many cases is a legal requirement in projects with activities potentially causing environmental degradation. In the case of agroecological projects, negative impacts are not allowed and an assessment is important to identify factors that distance them from the agroecological proposal. Based on the literature, the EIA, in general, is done with electronic spreadsheets, there is no software focused on the process. In view of this, the objective of this article was to carry out a diagnosis of environmental impacts in the Brígida Irrigation Project - Orocó/PE during the planting of different crops and animal husbandry, presenting a system to facilitate this task, named SAIA - Impact Assessment System Environmental, which can point out impacts that detract from an agroecological theme project. For this, after a survey on EIA techniques and agroecological projects, on the basis of scientific works and patents, the SAIA was validated in that Project, with questionnaires being applied with the participating family farming producers, to align the tool to the agroecological proposal. The diagnosis allowed us to conclude that there are negative impacts that keep the Project away from agroecology for all analyzed crops and creations. It is noteworthy that the number of impacts is not fixed for each type of crop, as it depends on how the steps are carried out. Furthermore, there was good acceptance of the tool, with suggestions, which were accepted, bringing SAIA closer to the reality of producers.

Low Carbon Agriculture Plan: an analysis for the period 1990 - 2018

2023-12-11T12:00:19-03:00

This article aimed to present the goals of the ABC Plan for low-carbon agriculture, and uses the multiple regressions modeling technique to investigate economic activity variables in relation to CO₂ emissions over the period from 1990 to 2018 in all Brazilian states. The results show that the CO₂ emissions in the states, have the same behavior as the land use change timeline, and that public policies and society actions were fundamental to the decrease verified in both CO₂ emissions and the change in use, of the land observed from the year 2004 until 2010. From this year, followed a trend of stability in CO₂ emissions and land use change. Another important characteristic is that despite the decrease in the number of deforestations, economic activities continued to grow in the regions, which demonstrates that there may be an increase in production even though the numbers of deforestation and CO₂ emissions are decreasing. This information, strengthen the Low Carbon Agriculture Program, as the main strategy for the development of the productive sector, mainly for sustainable agriculture.

A synthesis of a comparative analysis of the effectiveness of strategic environmental assessment between Ireland and Scotland applied to Brazil

2023-12-11T12:00:16-03:00

Strategic Environmental Assessment (SEA) aims to facilitate both integration and assessment of opportunities and threats for action strategies within the framework of sustainable development. Its stages comprise Screening, which analyzes its need, Scoping, which establishes the range of environmental issues to be covered, Analysis, in which the Environmental Report is prepared, Decision-Making, Follow-up, in which both Monitoring and Follow-up of the assessment are conducted, and finally Consultation. Three types of effectiveness approaches, namely procedural effectiveness, substantive effectiveness, and transactional effectiveness can be identified. This article addresses the effectiveness of SEA in Brazil, Ireland, and Scotland through a comparative analysis, since it enables rich discussions on the subject.

Geomorphological mapping of the Vacacaí river hydrographic basin (BHRV): Geomorphology as a subsidy to the knowledge of the physical environment

2023-07-14T16:52:00-03:00

Relief and its dynamics are understood as complex and the result of numerous exogenous and endogenous relationships. Geomorphological mapping emerges as an important tool for characterization and interpretation of geomorphological characteristics. The present work aims to present a geomorphological characterization of the Vacacaí River Hydrographic Basin (BHRV) based on different scales of analysis and cartographic products. The geomorphological classification presented here is based on the methodology proposed by Ross (1992), with adaptations and automation of the definition of cartographic products, thus defining 4 levels of analysis. In terms of results, there is a predominance of sedimentary structures from the Peripheral Depression, morpho sculptures from the Jacuí River Depression, patterns of smooth hills over sedimentary and elements from flat áreas. The methodology proved to be efficient and brought important aspects of relief and cartographic products that can serve for spatial organization actions.

SWOT Matrix as a tool for diagnosing the municipal water supply system of a small city: a case study

2023-07-14T16:51:56-03:00

Small municipalities often face challenges related to their water supply systems, such as limited financial resources, low population densities and limited organizational capacity. In this context, this study aimed to diagnose the water supply system in the city of Quatro Pontes - PR, which serves 2,628 economies, through SWOT analysis. This analysis consisted of determining the strengths, weaknesses, opportunities and threats of the system, listed based on reports from employees and visual inspections. It was found that the system presents factors already documented for small municipalities with autonomous services, such as the strengths “good water quality” and “easy maintenance”, as well as the weaknesses “few financial resources applied” and “outdated pricing policy”. In addition, opportunities were mentioned, such as technological innovations in the sector, and threats related to water waste and contamination by pesticides. The results presented depict the water supply system of the municipality and can direct managers to take advantage of opportunities and mitigate system threats.

Case study: characterization of solid waste management system in metallurgic companies of Joaçaba/SC

2023-07-14T16:51:52-03:00

The development of a country is intimately linked to the industrial development that is responsible for wealth generation, jobs and income, however, it is followed by serious environmental impacts caused by production and incorrect disposal of waste. The present research aimed to characterize the solid waste management system in metallurgic companies from Joaçaba/SC. For this, a research instrument was applied containing twelve open questions for the heads of seven companies. The questions included the identification of solid waste generated in the production process and the disposal method, as well as information about environmental licensing and reverse logistic. The research showed that only one company has an environmental management system and has a better understanding about its environmental responsibilities, both the management of waste generated by the production process and the importance of preserving the environmental.

The School Garden as an interdisciplinary resource for teaching and learning in the early years

2023-09-29T10:42:43-03:00

This work aims to present the contributions of a vegetable garden in the school context of Elementary School - early years, providing the interdisciplinary teaching of Science, Mathematics, Arts, Physical Education, Religious Education, Geography, History, English Language, Portuguese language, and contemplating the general competences of the National Common Curricular Base. The study was developed with fifth grade students at an Elementary School in the city of Santa Maria (RS, Brazil). For its effectiveness, we sought to understand the National Common Curricular Base and its general competences about interdisciplinarity and the concepts worked in the different disciplines that go through the Initial Years of Elementary School. The dynamics of work were guided by a didactic sequence that guided the activities, namely: 1th) Investigation of previous knowledge of students; 2th) Recognition of physical space for the construction of the garden; 3th) Research on cultures; 4th) Planning of the interdisciplinary activity; 5th) Construction and management of the School Garden; 6th) Contribution of each curricular component in the School Garden; 7th) Impact of the interdisciplinary activity. The vegetable garden, which was planned and built together with teacher and students, presented itself as a concrete environment for the realization of practical activities by students, allowing them to relate theory and practice as well as the approach of concepts in an interdisciplinary way.