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This work is concerning to production of quicklime (CaO) from thermal decomposition of the calcite limestone (CaCO3) using analytical and instrumental techniques (TGA and MS) to evaluate kinetic and thermodynamic effects as well as heat/mass transfer associates with the process operation. On the other hand, experiments of morphologic, structural and textural characterization (XRD, SEM and BET surface area) were carried out in order to evaluate the quality of the quicklime produced. Under experimental studied conditions it was observed that carbon dioxide (CO2) inhibits the thermal decomposition reaction rate. In addition, it was observed that steam (H2O) can catalyze this reaction but it can also cause sintering of the oxide formed. It was also observed that the calcination reaction is greatly limited by mass transfer effects and that the controlled thermal decomposition generates an increase in the solid porosity. The formed CO2 have also increased the sintering phenomena in the oxide structure, resulting in less reactive quicklime.

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The use of biomass for energy generation has aroused great attention and interest because of the global climate changes, environmental pollution and reduction of availability of fossil energy. This study deals with pyrolysis of four agricultural wastes (sawdust, sugarcane straw, chicken litter and cashew nut shell) in a fixed bed pyrolytic reactor. The yields of char, liquid and gas were quantified at 300, 400, 500, 600 and 700oC and the temperature and pressure effects were investigated. Pyrolytic liquids produced were separated into aqueous and oil phases. XRF spectroscopy was used for qualitative and quantitative elemental analysis of the liquids and solids produced at whole temperature range. Calorific value analysis of liquids and solids were also performed for energy content evaluation. Experimental results showed sawdust, sugarcane straw and cashew nut waste have very good potential for using in pyrolysis process for alternative fuel production.

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This work deals with implementation of an experimental flowrate control unit using free and low-cost hardware and software. The open-source software Processing was used to develop the source codes and user graphical interface and the open-source electronic prototyping platform Arduino was used to acquire data from an experimental unit. Work presents descriptions of the experimental setup, the real-time PID controllers used and theoretical/conceptual issues of Arduino. PID controllers based on internal model control, minimization of the integral of time-weighted absolute error, Ziegler-Nichols, and others were tuned for setpoint and load changes and real-time runs were carried out in order to make real-time use of  control theory learned in academy. Results showed the developed platform proved to be suitable for use in experimental setups allowing users compare their ideas and expectations with the experimental evidence in a real and low-cost fashion. In addition, the instrumentation is simple to configure with acceptable level noise and particularly useful for control/automation learning with educational purposes.

This work aims to investigate the efficiency of a novel organic mineral fertilizer produced with filter cake residue from sugarcane mills. The novel fertilizer was developed based on the mixing of minerals with an organic compost, conditioning, and pelletizing of mixture. The minerals consist of conventional soluble mineral nutrients and the organic phase consists of insoluble filter cake compost obtained from an assisted composting process. Efficiency of conventional and organic mineral fertilizers was measured in real field soybean crop through a randomized block design with four replications. Variables analyzed were productivity, NPK nutrient in leaves. The experiment was carried out in Tupaciguara/MG, Brazil. Experimental results showed higher soybean productivity and leaf nitrogen content in the organic mineral treatments than mineral ones in all dosages tested, with statistical relevance for 80% and 100% NPK dosages.