Análise estrutural do conjunto de palhetas de um aerador da estação de tratamento de efluentes

This work aims to find the maximum tension in a group of blades in a Sewage Treatment Stations in a company located in Vale do Paraíba. First, the calculations of the strength requested by the effluents on the structure are done, and the optimum torque of the frame screws is researched. From these data, static simulations using appropriate software and the finite elements method are performed. Based on the results, a possible solution to reduce the strength in this structure is proposed. This study will be provided as a consultation material to the company

O lodo de esgoto como fator de supressão de fitopatógenos

O descarte ideal para um resíduo altamente poluente somado à necessidade de se diminuir o uso do agrotóxico nas plantações, faz com que estudos sejam direcionados para a utilização do lodo de esgoto como fator de supressão de fitopatógenos. Alguns pesquisadores já encontraram resultados bastante animadores, atribuindo aos resíduos das estações de tratamento de esgoto, a diminuição dos sintomas ou até mesmo o total controle dos organismos fitopatogênicos. O trabalho teve como objetivo sintetizar os resultados, com ênfase em artigos científicos e trabalhos acadêmicos dos últimos 15 anos, da aplicação do lodo de esgoto, fornecendo subsídio para estudos posteriores e para o público em geral interessado no assunto. O foco principal foram os mecanismos envolvidos na supressão de micro-organismos causadores de doenças em plantas, mas foram abordados os métodos de obtenção e aplicação, a problemática de substâncias e micro-organismos potencialmente perigosos presentes no lodo de esgoto, bem como os principais pontos relevantes da utilização florestal e agrícola do resíduo

Procedimento para homologação de sistemas ecoeficientes para obtenção de créditos de carbono

This paper deals with the homologation process for obtaining carbon credits through the Clean Development Mechanism (CDM), that regulates the greenhouse gases reductions under the rules of the Kyoto Protocol. The CDM evaluates projects through a project cycle, which begins with the preparation of the Project Design Document (PDD) until the project certification to receive Certified Emission Reductions (CERs), popularly known as carbon credits. This study analyzed the implementation of the system Burner Recorder System for Low Flows of Biogas (QRBBV), developed by Marcelino Junior & Godoy (2009), in an eco-friendly wastewater treatment mini-plant (miniEETERA), built at the site of UNESP - Guaratinguetá SP. The QRBBV system is low cost and high reliability, developed to burn the methane generated at sites of low and variable production of biogas, which is not economically justified their energy recovery. Currently, almost all wastewater generated at the site of the campus is being treated by miniEETERA and, as a result, the biogas originated by this activity is being released into the atmosphere. Therefore, the project activity aims to capture and burn the biogas generated by miniEETERA, reducing the negative effects caused by the methane emissions into the atmosphere and, thus, claim to receive carbon credits. This work aimed to demonstrate the project applicability under CDM through the study and preparation of the PDD, as well as an analysis of the entire project cycle required for homologation. The result of the work obtained an estimate of only 20 CERs per year and proved to be economically unviable for approval through the CDM, since the spending with the approval process would not be compensated with the sale of CERs, mainly due the low carbon price in the world market. From an environmental standpoint, the project is perfectly... (Complete abstract click electronic access below)