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This study estimates and fills real flaws in a series of meteorological data belonging to four regions of the state of Rio de Janeiro. For this, an Artificial Neural Network (ANN) of Multilayer Perceptron (MLP) was applied. In order to evaluate its adequacy, the monthly variables of maximum air temperature and relative humidity of the period between 05/31/2002 and 12/31/2014 were estimated and compared with the results obtained by Multiple Linear Regression (MLR) and Regions Average (RA), and still faced with the recorded data. To analyze the estimated values and define the best model for filling, statistical techniques were applied such as correlation coefficient (r), Mean Percentage Error (MPE) and others. The results showed a high relation with the recorded data, presenting indexes between 0.94 to 0.98 of (r) for maximum air temperature and between 2.32% to 1.05% of (MPE), maintaining the precision between 97% A 99%. For the relative air humidity, the index (r) with MLP remained between 0.77 and 0.94 and (MPE) between 2.41% and 1.85%, maintaining estimates between 97% and 98%. These results highlight MLP as being effective in estimating and filling missing values.

This work aims to investigate a biogas steam reforming prototype performance for hydrogen production by mass spectrometry and gas chromatography analyses of catalysts and products of the reform. It was found that 7.4% Ni/NiAl 2 O 4 /g-Al 2 O 3 with aluminate layer and 3.1% Ru/g-Al 2 O 3 were effective as catalysts, given that they showed high CH 4 conversion, CO and H 2 selectivity, resistance to carbon deposition, and low activity loss. The effect of CH 4 :CO 2 ratio revealed that both catalysts have the same behavior. An increase in CO 2 concentration resulted in a decrease in H 2 /CO ratio from 2.9 to 2.4 for the Ni catalyst at 850 C, and from 3 to 2.4 for the Ru catalyst at 700 C. In conclusion, optimal performance has been achieved in a CH 4 :CO 2 ratio of 1.5:1. H 2 yield was 60% for both catalysts at their respective operating temperature. Prototype dimensions and catalysts preparation and characterization are also presented.

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