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Introduction: Marabú, Dichrostachys cinerea (L.), is identified as an important source of biomass for electricity generation in Cuba, so large quantities are demanded, forcing its harvest mechanization. Its obtained properties under mechanized conditions have not been profundity studied. Objective: To determine elemental composition, proximate analysis, ash content, ash chemical composition and heat value of marabú harvested with the BMH-480 machine with H 600 head as fuel. Materials and Methods: By direct harvesting process observations, the factors that could have the greatest influence on marabú as a fuel, properties, were determined. Harvested marabú corresponding samples were obtained and their properties were determined in several laboratories. Results and Discussion: In the first part of a two articles series, several of the most important properties of mechanically harvested marabú and their dependence with field density and machine cutting height, are presented. Conclusions: Elemental composition, proximate analysis and dry mass combustion specific heat (higher 19,15 MJ/kg and lower 17,85 MJ/kg) were determined. A tendency to increase the heat of combustion with the cutting height was found and ash content mean value varied between 4,07 and 4,45%. [ABSTRACT FROM AUTHOR]

Introduction: Marabú, Dichrostachys cinerea (L.), is identified as an important source of biomass for electricity generation in Cuba, so large quantities are demanded, forcing its harvest mechanization. Its obtained properties under mechanized conditions have not been profundity studied. Objective: To determine elemental composition, proximate analysis, ash content, ash chemical composition and heat value of marabú harvested with the BMH-480 machine with H 600 head as fuel. Materials and Methods: By direct harvesting process observations, the factors that could have the greatest influence on marabú as a fuel, properties, were determined. Harvested marabú corresponding samples were obtained and their properties were determined in several laboratories. Results and Discussion: In the first part of a two articles series, several of the most important properties of mechanically harvested marabú and their dependence with field density and machine cutting height, are presented. Conclusions: Elemental composition, proximate analysis and dry mass combustion specific heat (higher 19,15 MJ/kg and lower 17,85 MJ/kg) were determined. A tendency to increase the heat of combustion with the cutting height was found and ash content mean value varied between 4,07 and 4,45%. [ABSTRACT FROM AUTHOR]

Introduction: Particulate material presence in atmosphere causes a variety of impacts on vegetation, materials and humans. The main emissions of "Desembarco del Granma" textile factory are originated from fuel oil burning in oil heaters and steam-generating boilers. Emissions can be estimated using emission factors. Objective: To determine the necessary technological proposal to reduce the air quality impact caused by particulate material generated in auxiliary combustion processes in "Desembarco del Granma" textile factory. Materials and Methods: Emission factors were used. Dispersion modeling of PM10 was performed using a specialized software from the Provincial Meteorological Center, based on a Gaussian plume model. Aspen Plus 8.0 software was used. Results and Discussion: The emissions of PM10 and PM 2.5 were estimated. PM10 immissions reach maximum values of 100 µg/m3. These values show a poor air quality category because it's exceeding the provisions of NC 1020 (2014). By means of Aspen Plus, the characteristics that cyclones will add to the considered fixed sources were determined. The Stairmand-HE type was selected. Conclusions: The proposal to mitigate particulate material environmental impact consists in two cyclones installation, one in the steam generator and the other one in the oil heater of the engineering services plant "Desembarco del Granma". [ABSTRACT FROM AUTHOR]

This paper proposes a methodological order of the different steps to evaluate the heat emitted in a bioreactor, supported by principles of Mass and Energy Balances. It is sustained by the concepts derived from the conservation of the available electrons, the degree of reduction and some experiences in the determination of the combustion heat of the cells of microorganisms. [ABSTRACT FROM AUTHOR]

This paper proposes a methodological order of the different steps to evaluate the heat emitted in a bioreactor, supported by principles of Mass and Energy Balances. It is sustained by the concepts derived from the conservation of the available electrons, the degree of reduction and some experiences in the determination of the combustion heat of the cells of microorganisms. [ABSTRACT FROM AUTHOR]