ABSTRACT Brazil has been facing a huge rise in fuel and diesel prices due to the rise in the international market and the war between Ukraine and Russia. The rise in electricity prices is also a problem that affects everyone in Brazil. This study aimed to evaluate the performance and emissions of a diesel engine for power generation that operates with crambe-based fuels with blends of 0% (control), B5, B10, B15, B20, B50, B70, and B90. The fuels were tested in an 8 kVA generator engine at a load of up to 6000 W. The biofuels were obtained from a mixture of diesel with crambe biodiesel at incremental levels from B0 to B90 in the fuel mixture. The increased proportion of crambe biodiesel resulted in lower specific consumption. Crambe biodiesel resulted in a reduction of CO, CO2, and NO2 emissions due to an increase in crambe biodiesel at the proportion. The results indicate that crambe biodiesel blends are viable technical solutions for the partial replacement of conventional diesel.

ABSTRACT Sesame ( Sesamum indicum L.) oilseed needs to be studied in relation to the production of biodiesel and its application as an alternative to the soybean biodiesel used in Brazil. The aim of this study was to evaluate biodiesel blends (B0, B5, B10, B20, B40, B80, and B100) of sesame in the performance and emissions of engines. A few studies of sesame biodiesel in engines were found in the literature imparts novelty to the current study. The fuels were tested in a 5-kVA generator engine at loads ranging from 1000 to 6000 W. The results of the analysis showed that the increase in the sesame biodiesel blend caused a reduction in the specific fuel consumption (SFC), carbon monoxide (CO) emissions, and an increase in nitrogen oxide (NOx) emissions. The SFC of sesame biodiesel (B100) was 11% higher than that of diesel (B0). CO emissions increased 39% for diesel (B0) compared to sesame biodiesel (B100). However, B20 showed lower SFC than diesel and lower gas emissions than B80 and B100 blends. Therefore, sesame biodiesel, especially up to B20, is a viable alternative for the partial replacement of conventional diesel. Sesame biodiesel should be considered as a promising candidate for alternative fuels.

RESUMO Este trabalho objetivou avaliar os custos envolvidos na construção de modelos de biodigestores (indiano, chinês e canadense) no município de Cascavel – PR. Determinaram-se os custos de produção de energia a partir do biogás produzido por dejetos de caprinos, bovinos e suínos, para sistemas de semiconfinamento. Foram utilizadas propriedades rurais com 20; 40; 60; 80 e 100 animais de cada um dos três grupos avaliados. A partir do volume de dejetos produzidos por animal, foram dimensionados os biodigestores e calculados os custos para a construção e a implantação de cada modelo, e o custo total da produção anual de energia em função do número de animais. O biodigestor modelo canadense apresentou o menor custo de construção e de implantação, variando de R$ 2.104,00 a R$ 7.266,00. A geração de energia com dejetos de suínos apresentou o menor custo, variando de 0,015 a 0,050 R$/KWh em biodigestor modelo canadense. A maior produção anual de energia foi verificada para bovinos, variando de 24.090 kWh/ano a 120.450 kWh/ano, para os três modelos de biodigestor em estudo.

ABSTRACT This study aimed at assessing the costs incurred in building different biodigester models (Indian, Chinese, and Canadian) in Cascavél – PR, Brazil. We also determined costs related to biogas production from goat, bovine, and swine dungs in semi-confinement systems. For this purpose, we evaluated farms with herds of 20, 40, 60, 80, and 100 animals of each group. The biodigesters’ volume were based on each animal amount of excrement and, then, we calculated the costs for building and implementing each model, as well as costs associated to annual energy production on the number of animals used. The lowest cost was observed for Canadian biodigester with respect to both building and implementation, ranging from R$ 2,104.00 to R$ 7,266.00. Power generation using swine waste had the lowest costs varying 0.015 to 0.050 R$/ kWh with Canadian model. The largest annual energy production was recorded for bovine dung, varying 24,090 to 120,450 kWh/ year for the 3 studied models.

A conscientização da importância do meio ambiente tem incentivado o estudo de novas fontes energéticas renováveis e menos poluentes. Dentre essas fontes, a energia solar destaca-se por ser perene e limpa. A utilização da energia solar em sistemas de aquecimento de água residencial rural pode colaborar com a economia de energia elétrica, base da matriz energética brasileira. Conhecer os fatores que influenciam na operação de um sistema de aquecimento de água por energia solar é importante na determinação de sua viabilidade técnica, visando a sua difusão em residências rurais. Para tanto, construiu-se um protótipo, no câmpus da Faculdade Assis Gurgacz, em Cascavel - PR, com características similares a um equipamento utilizado em residências para dois habitantes, para funcionar com circulação natural ou termossifão e sem auxílio de sistema de aquecimento complementar. O equipamento mostrou-se viável tecnicamente, alcançando a temperatura mínima para banho de 35 °C, sempre que a radiação solar foi superior a 3.500 Wh m-2, o que aconteceu para a maioria dos dias estudados.

The awareness of the importance of the environment has stimulated the study of new renewed energy sources and less pollutant. Amongst these sources, solar energy stands alone for being perennial and clean. The use of solar energy in systems of agricultural residential water heating, can complement the economy of electric energy, base of the Brazilian energy matrix. Knowing the factors that influence the operation of a system of water heating by solar energy is important in determining their technical viabilities targeting their distribution in agricultural residences. To evaluate equipment of water heating for solar energy, a prototype was constructed in the campus of Assis Gurgacz College, in Cascavel,State of Paraná, Brazil, with similar characteristics to equipment used in residences for two inhabitants, to function with natural circulation or thermosiphon and without help of a complementary heating system. The equipment revealed technical viability, reaching the minimum temperature for shower, of 35 °C, whenever the solar radiation was above the 3,500 Wh m-2, for the majority of the studied days.

Resumo Resíduos sólidos verdes provenientes de podas urbanas e de sobras de produtos hortifrutigranjeiros, assim como efluentes das atividades de suinocultura, apresentam-se como um dos principais problemas nas áreas urbanas e rurais. Uma alternativa à estabilização desses resíduos é a compostagem, seguida do processo de vermicompostagem. Neste estudo, avaliou-se a integração da compostagem e vermicompostagem na bioestabilização de resíduos sólidos verdes urbanos, utilizando-se água residuária da suinocultura e ativador comercial. Os resultados demonstraram a possibilidade da utilização da água residuária da suinocultura como agente inoculante, em substituição ao ativador comercial, visando a produção subseqüente de vermicompostos. Os metais zinco e cobre foram detectados nos vermicompostos obtidos, entretanto, em concentrações que não oferecem riscos de contaminação ao solo, plantas e à saúde humana.

Abstract Green solid residues from urban pruning, rests of agricultural products and swine wastewater are problems in urban and rural areas. A alternative to stabilization of these residues is composting followed by wormcomposting. In this study the integration of composting and wormcomposting in the biostabilization of the urban green solid residues with swine wastewater and commercial activators was evaluated. The results showed the possibility of the swine wastewater utilization as inoculate agent, in substitution of commercial activator, with the objective of producing subsegmently wormcomposts. The metals zinc and copper were detected in obtained wormcomposts, however, their concentrations did not offer risk for human health, plants and soil contamination.