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)

Estudo das propriedades ópticas de pós cerâmicos à base de Zn3Ga2Ge2O10: X% Cr3+ (X = 0 ; 0,5 ; 0,75 ; 1,0)

Ceramic powders based on Zn3Ga2Ge2O10: Cr3+ X% (X = 0.0; 0.5; 0.75; 1.0) were synthesized by solid-state reaction method. The gallium-zinc germanate doped with chromium presents an interesting property of phosphorescence, that means, it is capable of emitting light when excited by a source of radiation, and such emission remains for some time after stopping the source. For this reason, these materials can be widely applied in night-vision surveillance, (through the use of solar energy, for example), electronic devices screen, emergency routes signals, control panels indicators in dark environments, etc. In this job were considered different amounts of dopant in order to perform a comparison of structural and photoluminescent properties. For that, some analyses were performed on samples, such as XRD, FT-Raman, SEM, UV-vis and photoluminescence measurements (PL). Such analysis allowed to infer that the presence of chromium results in no phase transformation, so that the four compositions have the same set of phases: cubic, rhombohedral and hexagonal. Although the structure was not changed, chromium influences other properties / characteristics of these materials. Examples are: increase of band-gap, decrease of average particle size, small changes in binding energy checked by Raman and especially the increase of photoluminescent property. The chromium ions have great ease in replacing gallium ions in octahedral sites, resulting in emission of light with a wavelength of about 700 nm (infrared region), which is justified by the spin-forbidden 2E 4A2 transition. In other words, chromium is a favorable luminescent center, acting as a trap in the crystal structure, since it imprisons the excitation energy easily and releases it gradually, allowing the phosphorescence. It was observed that the composition ... (Complete abastract click electronic access below)