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The objective of this work was to verify the potentiality from the pulps to the soda-antraquinona of pine for the production of papers wave, liner and newspaper (blended with trash pulp), using adapted technological outlines of one manufactures of trash pulps. The work was carried out with pine chips coming from the north area of Missions, according to a prosecution indicated by Tucumán paper mill. In the case of liner and wave, the reached yield was of 67 % and the results indicated that the used process (soda-AQ of pine, with impregnation of 25 % of the chips) it is adapted for the obtaining of pulp brown semichemical. The obtained pulp presented a quality more than enough to be used in the production of papers liner, being in the inferior limit of quality for the production of papers wave (130 g/m², RCT 1,56 kN/m, CMT 172 N). with regard to the periodic paper, the pulp with yield of 61 % was refined blended with trash pulp in different proportions and it was whitened with NaClO with an objective target of 70 %ISO. The best mixture was that of 90% of trash pulp and 10 % of pulp pine semichemical. [ABSTRACT FROM AUTHOR]

In this paper it has been presented the results about the study with high pressure steam schemes for the energy integration of a sugar mill with a pulp paper factory. The hypothesis for the integration is that it is possible to produce heat and electricity for both factories with the biomass of the sugar cane. This study includes the diversification of the production whit an ethanol factory for the pulp. The by bibliography, energy, material and cost balances are the main subjects for the best alternative of integration with high pressure schemes. The scheme with 61 ata and 440 °C was the best technically but not in the economic sense. [ABSTRACT FROM AUTHOR]

In this paper is carry out a study about the quality of paper board 127 g/cm², which is produced from a mix of paper pulp and bagasse pulp, the latter boiled at a high pressure, approximately at 14 kgf/cm², and using as solvent 1.5-2.5 % of soda y 50% of ethanol. To evaluate the property CMT paper sheets were made in a laboratory. The CMT values were extrapolated at industrial level using the correlations obtained between the two levels of study. These correlations were determined from experimental study. In this work was shown that to use high pressure during the boiling in the organosolv pulping are obtained a paper board of a better quality than that of the paper obtained in the process where normal pressure is used. [ABSTRACT FROM AUTHOR]

An energy study was performed at Pulpa Cuba Paper Mill, located in Sancti Spiritus, where an energy management system was applied according to NC: ISO 50001, in order to assess the energy system by applying energy management systems for energy and water reduction in the paper mill, in which the current steam generation, distribution and consumption system is diagnosed. The proposal of a modified energy scheme with 1 MW Backpressure Steam Turbine Generator and rehabilitation of the original boiler or installing a lower capacity boiler contributes to save financial resources by the concept of water, fuel and electricity. The implementation of four projects will save 3,095,574 CUC / y and an average payback period of about 1 year is expected. [ABSTRACT FROM AUTHOR]

In the paper are exposed the possibilities of achieving a clean technology of production of corrugated paper from the employment of the pounding of the trash of sugar cane with ethanol. Were established the possibilities of achieving, by means of an analysis, processes of material and energy integration of the manufacture of sugar and installations of production of by-products. These processes are technologically and energetically sustainable, environmentally compatible, and economically competitive based in the benefits that can be achieved through the material and energy integration of the sugar cane by-products and the possibility of producing celluloid pulps with ethanol for corrugated cardboard, and by-products from the lignin obtained in the process. [ABSTRACT FROM AUTHOR]

In this paper are presented the results obtained in experiments where the traditional pulping method of bagasse is substituted to obtain semi-chemical pulps used as reactive caustic soda, destined to the production of cardboard, by organosolv pulping using bio-ethanol as deslignifying agent, as a way to minimize the pollution in the paper industry. In this study were evaluated 14 physical properties with the objective of analyzing in a wide spectrum the influence that this kind of pulping has above the board paper properties. The experiments were carried out at Pilot Plant level, and the independent variables chosen were: ethanol per cent, soda per cent, and degree of grinding. The results were analyzed by using Statgraphic software. The optimal operation conditions were obtained using LINGO software, through which it was applied the hierarchic optimization method. [ABSTRACT FROM AUTHOR]

In this work is developed a methodology for the optimization of energy consumption of the refining process to obtaining of pulps, on the base of the denominated Refinement of the Sequential type that allows to adjust, with the minimum energy cost, the quality of the mixture of the pulps for a certain type of paper. The Method of Design of Experiments of Simple Lattice is used, for studies of mixtures of three or but components with a reduced one number of experiments and keeping in mind the necessary restrictions of the process and qualityof the product. It is applied in this case for a type of pulp of waste paper. It is demonstrated that alone it is necessary to refine fractions of the pulp to process until a suitable degree to obtain a good mixture that allows to reach alone the degree of necessary development of properties for their reuse and to avoid that it is drained too much. [ABSTRACT FROM AUTHOR]

This work is part of a sustained I make an effort to increment the competitive of the companies producers of paper for corrugation also named paper midium, utilizing for it- of form alternating pulps, between the which they have possibilities of utilization the recycled paper and the fibers gotten with the process organosolv (etanol-water) starting from the trash of cane of sugar, that is a by- product of the fabrication of sugar. The investigation was carried out with support of an experimental design of grating simple. The outputs that were gotten show that a combination of the 33% of Old Corrugated Continer (OCC) and 67% of fiber organosolv (1,5% of flat and high level of alcohol) with Number of kappa 84,5, it has similar outputs to the Flat Crush Resistance Lab-corrugated of paper (CMT) (140,58 N ó 31.6 lbf of industrial paper), to the of a combination of 65% of OCC with 35% of Organosolv Pulp (1,5% of flat with low level of alcohol), with Number of Kappa of 78,5. [ABSTRACT FROM AUTHOR]

En la planta Damují de la provincia de Cienfuegos, Cuba, se produce una gran parte del papel kraft empleado en las cajas de cartón que se usan como envases y embalajes. Esta empresa ha presentado diversos problemas con las autoridades ambientales por la contaminación que genera a su río homónimo, hacia el cual vierten sus efluentes líquidos y por las emisiones de gases y el consumo excesivo de su caldera de generación de vapor. El proceso de producción estaba sujeto a la introducción de tres posibles mejoras: Cierre del circuito de agua, el cual permitiría reutilizar el agua en el proceso reduciendo su consumo actual y el uso de aditivos químicos, los cuales también se recuperan; cambio de la caldera de generación de vapor por una más eficiente, lo cual disminuiría la cantidad de vapor generado por unidad de combustible; la otra posible alternativa era la reactivación del sistema de residuales de la planta, el cual se encontraba en muy mal estado. El presupuesto de la entidad no era suficiente para llevar a cabo todas estas mejoras y se requería priorizarlas. Es por ello que se debieron aplicar estudios de Análisis de Ciclo de Vida (ACV) y la simulación del proceso para evaluar técnica, económica y ambientalmente las alternativas. Según esta investigación se pueden ejecutar, el cambio de la caldera y la reactivación del sistema de residuales o el cierre del circuito de agua, decidiéndose por esta última según los criterios planteados. [ABSTRACT FROM AUTHOR]

Introduction: Steel foundries are significant pollution sites with manual molding and demolding processes, therefore technology has moved on to molding using self-fragrance resins. In this paper, the Life Cycle Analysis (LCA) methodology is applied to evaluate the environmental impacts in a foundry process subject to this technological investment. Objetive: To evaluate the environmental impact of a technological proposal in the molding stage in a steel foundry. Materials and Methods: The input and output flows of the mixtures of sand, gases and solid waste in the traditional molding and chemical molding processes for the production of one ton of steel, as a functional unit, were evaluated and inventoried. SimaPro 8.0 software was used to obtain LCA results. Results and discussion: The results demonstrate the economic and environmental feasibility of chemical molding. In the analysis, it was verified that the return sand is the raw material with the greatest benefit to the impact categories, favoring from climate change to human health and limiting the formation of particles that affect health, ecosystems and natural resources. Conclusions: The LCA methodology quantifies the environmental impacts of steel production and justifies the economic-environmental feasibility of chemical molding, verifying that the return sand is the raw material with the greatest contribution to the impact categories and, as an avoided product that is recycled, favors in the new technology the environmental and damage categories. [ABSTRACT FROM AUTHOR]

A review the principles by optimization of refining operations of bagasse pulp in disk refiners are discussed in this paper. These principles are used to research the semichemical and bleached chemical bagasse pulps from Cuba's Paper Industries. The best results were obtained with cutting angle from 70° grad and low level of specific edge load (0.75 N) and specific energy consumption (100 kWh/t). [ABSTRACT FROM AUTHOR]

The generated black liquor of Organosolv process from sugarcane bagasse was treated with white rottenness Phanerochaete chrysosporium fungi, for the realization of preliminary studies of evaluation of the decrease of the color, compound aromatic and demand oxygen chemistry (DQO). The studies were carried out in erlenmeyers. Different conditions of temperature and nutritional requirements were evaluated. The best results were obtained at 37°C and under conditions of nitrogen limitation with 38% of color decrease and 12% of decrease of the DQO. In the course of the experiment the activities of the lignin peroxidase neither manganese peroxidase were not detected, however this fungi is able to produce these enzymes. Starting from the obtained results, you can conclude that other independent factors of the presence of the enzymatic activities that cause these results exist. [ABSTRACT FROM AUTHOR]

Photovoltaic generation is considered an environmentally advantageous alternative over conventional energy sources. Although Cuba's energy system is fundamentally based on oil, advances are made in usage of these technologies. This paper objective is to propose an opportunity study of photovoltaic systems connected to grid in COPEXTEL Cienfuegos Territorial Division (DTCC) in order to reduce electricity consumption. PVsyst and RETScreen, design and simulation software for renewable energy systems are used. The profitability for the photovoltaic park in the roof area connected to the grid with internal loads and a total installed nominal power of 150 kW, was determined. The savings for DTCC could be of 2.86 million CUC and about 155 TCO2 are no longer delivered annually, demonstrating economic and environmental benefits. The opportunity to install a photovoltaic park connected to grid to cover the electricity demand is verified. [ABSTRACT FROM AUTHOR]

This paper calculates the ecological footprint in a municipality of Villa Clara province in 2013 using a software that has programmed all the mathematical expressions of Ress and Wackernagel methodology. The territory ecological footprint and carrying capacity in 2013 were 0.6603 ha/cap/year and 1.4233 ha/cap/year respectively, which indicates that it has a surplus, revealing the path towards environmental sustainability. Predictions of sustainability were made in desired and undesired future scenarios until 2025. The unwanted scenario was considered the progressive deterioration of the region's environmental quality, motivated by an increase in energy and crop sub footprints, idle area and forest area reduction, leading to an increase in the ecological footprint and decrease in carrying capacity with a deficit in 2023 of -0.0207 ha/cap/year. In desired scenario, reductions of the energy sub footprint, of idle and constructive surfaces are considered, as well as the sub footprint of forests and seas increase as well of agricultural and forest surfaces, which guarantees ecological footprint gradual reductions and load capacity increases with surplus increases. [ABSTRACT FROM AUTHOR]

This paper describes the manufacture and validation of a wet erosion testing machine. Based in norms for the erosive test and non-standardized machines reported in scientific publications analysis, a machine that responds to research and teaching needs is development. For test equipment design was considered that manufacturing cost was low and its technological simplicity in order to make manufacturing viable. A variable speed stirrer with a tool holder for coupling the sample holder was used on the manufacture of this machine. This sample holder device allows two samples of trapezoidal configuration simultaneous testing. The machine was validated by testing, under sample holder different rotational speeds. Samples of an extractor blade and samples of coatings, obtained by manual welding with a coated electrode of recharge, were tested. [ABSTRACT FROM AUTHOR]

In this paper a conceptual instrument that confers an integral vision to Risk Management process due to intense drought is proposed. The use of methods such as the experts criterion enabled the adaptation of theories and universal standards of Risk Management on environmentally sustainable bases. The result is a conceptual model with essential characteristics as the interrelation between the pressure-state-impactresponse indicators with the strategic, systemic and participatory approaches that provide potentiality for decision-making facing increasingly frequent and prolonged events caused by precipitations scarcity. [ABSTRACT FROM AUTHOR]

The increasing production of metallic elements results in the generation of large number of by-products which in many cases are considered as industrial residuals. In this paper an alternative to reduce these residuals by an aluminothermy process is proposed. The mixture studied consists in particles from steel hot rolling processes, aluminum chips from the profiles machining and cutting processes and ash from petroleum combustion of. As a result of this process an iron alloy with carbon contents of 3.62%, silicon of 0.47%, manganese of 0.25% and aluminum of 11.16% was obtained. In addition groups of other alloy elements with appreciable value, such as: Cr, Mo, Ni, V, Ti, Nb, and Co appears. The process evaluation is made from a comparison of the results obtained with those predicted in mass balance. The alloy obtained has prospects for industrial use. [ABSTRACT FROM AUTHOR]

The Theory of Inventive Problem Solving (TRIZ) is a method widely used today to solve engineering tasks and to develop new products. Two of the key foundations to apply TRIZ are the matrix of contradictions and the engineering principles. They have remained almost unchanged since their origin, and designers have difficulty using them successfully in a wide range of engineering problem configurations. The objective of this paper is to present the results of contradiction matrix and the engineering principles analysis, based on current scientific and technological development, as well as the modifications required in the field of mechanical engineering in general, applied to the design of plastic spur gear transmissions. [ABSTRACT FROM AUTHOR]

Electric motors are the main producers of industry motive power. They are machines that work with a relatively high efficiency, however, their oversizing for various reasons causes them to work occasionally with low efficiency. For this reason, the replacement of oversized induction motors is considered as an opportunity to save energy. However, it is necessary to verify that its oversizing is not necessary, since in high inertia loads case a higher power motor may be required to satisfy the starting requirements. In this paper, the analysis of replacement of oversized motors by others of lower power and higher efficiency class is carried out. The dynamic starting regime is analyzed and potential for economic savings and reduction of CO2 emissions are evaluated. The Steam Generation area of the UEB Central Azucarero 14 de Julio is taken as a study case. [ABSTRACT FROM AUTHOR]

The Cuban sugar industry opens possibilities for biorefinerydevelopment due the characteristics of its mass flow currents and its facilities for obtaining different products, co-products and energy. In present paper, biorefinery schemes were evaluated in a Cuban sugar factory with the integration of products and by-products. Two schemes were proposed for the development of a biorefinery in a Cuban sugar industry, considering the obtaining of second generation ethanol (2G) and third generation biodiesel (3G) (Alternative I), as well as obtaining ethanol from molasse -filters juices and bagasse hydrolyzed and biodiesel 3G (Alternative II). When analyzing these alternatives based on results of mass balances, the AlternativeI is not feasible from a technical point of view, since the amount of bagasse used for hydrolyzateproduction makes the plant not self-sufficient energetically, consuming 2 868 609 kW-h / year of the National Electric System (SEN). When carrying out the economic evaluation it was obtained that alternative IIis technically and economically feasible, since it has a NPV of $ 19 129 956, a TIR of 41.9% and a payback of 4.4 years, achieving in this way the integration of a sugar industry to a biorefinery that obtains second and third generation products. [ABSTRACT FROM AUTHOR]

Environmental performance of "Chichi Padrón"slaughterhouse is presented in this paper. As a first step the environmental assessment is conducted according to the methodology applied by CITMA and Conesamatrix is applied to assessenvironmental issues in order of priority, concluding that the two most significantaspects are reduction of water resources for other uses and pollution ofsurface waters by dumping of liquid waste. Subsequently the basic elements of the Environmental Management System are defined, and the methodological and scientific basis to eliminate or mitigate negative aspects caused to the environment are established. [ABSTRACT FROM AUTHOR]

Based on the international trend to increase steam parameters at cogeneration plants in sugar mills, this paper presents the results of a techno-economic assessment of rising steam parameters to 6,7 MPa/520 °C and 10 MPa/540 °C, at Cuban sugar mills. The assessment analyzes the economic effect at the sugar company level and the country level. It results that under the initial modeling conditions there is not enough incentive for the sugar company to invest in rising parameters at cogeneration plants due to poor return indicators. Then the study looks for the initial investment parameters that would turn it attractive to the company. Rising steam parameters and consequently the efficiency and energy production is always good for the country due to the lower bagasse based power generation cost and price paid for it. [ABSTRACT FROM AUTHOR]

An experimental study is carried out in present paper for the sorghum and ricebeerelaboration, which can be consumed by celiac patients. Its objective is to obtain this beverage using only sorghum malt, an exogenous Alpha-Amylase enzyme and The best adjunct for its production (rice or sorghum), studying independent variables such as enzyme concentration and adjunct type, as well as analyzing its effect in the final beer quality manifested in total reducing sugars, alcohol content and yield response variables using an experimental design of multilevel 2k. The type of adjunct and the concentration of enzyme are significant variables in response variables. With the adjustment made to the maceration curve, the behavior total reducing sugars were estimated from the Brix degrees for each type of adjunct used. The use of the highest concentration of enzyme and sorghum as adjunct determine a higher alcohol content. [ABSTRACT FROM AUTHOR]

A review of microfiltration, ultrafiltration and reverse osmosis techniques as alternative for both vinasses and sugar agroindustry wastewater management is showed in this paper. These techniques have been tested satisfactory in vinasse concentration in factories which produce ethanol from grains, in substitution ofconventional evaporators systems. The experiences with vinasses showed values of 75-99% for color retention, 70-99% for organic matter retention and between 60-99% of solid retention, depending of both membranes and membranes combination selected. From the results reported by several authors a two stages system for vinasse treatment is simulated in order to estimate its efficiency in total solids and organic matter retention and its investment and operation cost. [ABSTRACT FROM AUTHOR]

Determination of optimum temperature in the (PFasa) cellulase production, by a strain of Aspergillus niger in solid fermentationis presented in this paper, using data from a previously proposed kinetic model. Dependence of the 16 kinetic parameters with temperature (in the range of 20 °C to 40 °C), was established. For µmax and xmax parameters, the adjustment was achieved using the Rosso and Ratkowsky models respectively. Cubic interpolation models was needed to adjust the rest of kinetic parameters. The dependence of the kinetic model parameters with temperature allowed the estimation of temperature and optimum fermentation time to maximize the productivity in the production of true protein and the activity of the three studied enzymes. As result, the optimum temperature rangeisbetween 30°C and 32°C. For the production of true protein and CMcasa, the optimum fermentation time is located within the19 and 22 hours respectively, but for the production of PFasa, is 33 hours. The protease activity presented several local maxima in terms of optimal temperatures ranging from 25 to 40 °C. Although the maximum activity levels are 64 UI/gdm, which, according to literature, is an intermediate value, the level of productivity of PFasa is the highest found (3.84 times superior to average activity), when compared with another 20 reports consulted since 2004. [ABSTRACT FROM AUTHOR]

In this paper are explained some possibilities to integration in a productive complex the factories: pulp and paper Damují, sugar cane Guillermo Moncada factory, as well as a distillery and biomass factory. The two last will be installed near to the two first factories. In this way are appreciated an intensification in the sugar production. and the need to consider the uncertainly that exist in the raw material availability in the different processes, operational changes, technological and finance changes. An economical evaluation of the proposal solutions is carry out. [ABSTRACT FROM AUTHOR]

In this paper it has been presented the possibility of integration between a sugar mill and a pulp paper factory with two alternatives: the first one presuposes the rational utilization of the equipment, while the second comprises the remodelling the schemes of the integration, with a very little investment in the case of Cuba aimed at meeting the energetic demand under the conditions of the integration as well as the nominal capacity. The bibliography, energy and material balances are the main methods of researches used in order to demonstrated that it is not possible to develop the integration under the established conditions. [ABSTRACT FROM AUTHOR]

A geodesic dome is a mesh of bars and nodes arranged along the edges and vertices of a polyhedron on a surface that can be in the form of a sphere, parabola or ellipse. From knowing the advantages of this type of structure, they have been widely used in various constructions such as: housing, commercial offices, greenhouses, fair stand, fixed ceilings fuel storage tanks, among others. Many researchers have studied modeling and geometry of geodesic domes. The purpose of this paper is to present, from the review and compilation of information from several researches, an algorithm for generating a wireframe model of a geodesic dome for fixed roofs of spherical fuel storage tanks, for a further analysis of resistance by the method of finite elements. In this paper, we describe in detail the procedure and geometric expressions that were used. Finally, a computer program was developed in order to evaluate mathematical expressions and the procedure described in this paper and also to have a tool for generating computational model of a geodesic dome. [ABSTRACT FROM AUTHOR]

In this paper the process of improving the malting of sorghum UDG-110 is studied in the manufacture of beverages for celiac patients with adding chemicals in order to improve the malt diastatic power. The study was extended to the analysis of variables that most influence have in it, as the addition of a chemical reagent and the soaking time in levels of 0.1 and 0.4% w/w of 12 and 36 h respectively, keeping fixed the germination time in 72 h in a first study and continue delimiting the variables in a second and third analysis to determine the best conditions in the process of malting grain. In the last analysis, the variables were NaOH concentration in low levels of 0.01 to 0.05% w/w and soaking time at 12 and 36 hours, keeping fixed the germination time but in 54 h. Factorial design experiments central composite rotary 2k with central points was applied determining the moisture percent that was achieved in the soaking, germination percent, extract content, losses of malting and diastatic power as responses variables. The results indicate that the addition of a chemical agent in the soaking improves the malting process of the sorghum UDG-110, but at concentrations of 0.03% within the ranges utilized through the study of 0.01-0.5%, soaking time of 24 h and germination time of 60 h. [ABSTRACT FROM AUTHOR]

This paper presents the used methodology to calculate the present and future potentials of total biomass wastes, from the economic, social, environmental and technological point of view in accordance with the principles of sustainable development. From the values of sugarcane, coffee, rice, and sawmill wastes, through information provided by the main producing companies in Cienfuegos province, it was possible to determine the total energy delivered, as well as the amount of CO2 emitted into the atmosphere. In the case of the bagasse, the total energy was 4.409E+08 MJ, leaving 137 652.9 t CO2 to emit in the atmosphere. For the filter cake it was 7.093E+08 MJ and 221 423.9 tCO2. In the case of coffee and rice residues these values were 4.808E+05 MJ with 184 tCO2 for coffee and 6.34E+07MJ with 19 868.87 tCO2 for rice, respectively. Finally, the total energy for sawmill waste was 4.108E+07 MJ and 2 346.72 tCO2. [ABSTRACT FROM AUTHOR]

This paper shows the results of the study of the economic and social environmental impacts of concrete blocks production in Eco-materials workshop in Manicaragua city. This is an experimental area of local production in Villa Clara, which belongs to Habitat project. The Life Cycle Analysis (LCA) tool is used through the use of SIMAPRO 7.3 program. For the measurement of environmental impacts, the Eco indicator 99 methodology is applied, and the Life Cycle Cost Analysis (CCV) for the economic ones. The functional units evaluated are the 10 and 15 cm blocks manufactured with two alternatives: natural aggregate and recycled aggregate. The results show that the production of blocks of 10 and 15 cm with recycled aggregate have a greater environmental impact due to the fact that more cement is used than those made with natural aggregate, although they have less impact on the exploitation of the quarries. The economic effect indicates that the blocks with recycled aggregate are more economical at $ 0.16 for those of 10 cm and $ 0.23 for those of 15 cm because they reduce transportation costs and materials. The social impact reveals that the block manufactured with recycled aggregate tends to have a negative influence on health, since it uses more cement, but an additional production of two units is achieved in the case of the 10 cm blocks and three in the 15 cm blocks using the same amount of aggregates from the quarries. [ABSTRACT FROM AUTHOR]

The paper proposes the study of the environmental impact caused by the wastewater discharges in the Portoviejo River basin, through the evaluation of its self-purification capacity through the use of a mathematical model. It also shows the considerations to be taken into account for the application of the model, the location of the dumps and the model parameters adjusted from the experimental data showing the variation of the dissolved oxygen concentration regarding the corrected length of the stream considering the morphology of the river. From these parameters, the values of the re-oxygenation rate and oxygen consumption constants were calculated, which are used as the basis for the identification of the most critical river section and of the spills that affect the most the self-purification capacity. [ABSTRACT FROM AUTHOR]

Electric motors required by electric vehicles must be effective, efficient and economical. The accelerated development of power electronics and speed control with frequency converters allows the use of adjustable speed systems within a wide range. From a study of specialized literature, different types of synchronous motors without rotor windings were compared in this paper for these vehicles. Comparative assessments were made, based on momentum and power, losses and efficiency, power factor, costs and other characteristics of synchronous permanent-magnet motors, synchronous reluctance motors and synchronous reluctance motors assisted by permanent magnets. This allowed assessing the best technical-economic variant. It was shown that the last one, using ferrite magnets, ensures the lowest cost, with high absolute values and density of momentum and power, high efficiency and high power factor. [ABSTRACT FROM AUTHOR]

For an air-cooled vapor condenser (ACC), environmental wind can cause a large reduction of the flow in the axial fans mainly near the windward side of the air-cooled platform due to cross-flow effects, resulting in a reduction of heat transfer. This leads to an increase in the turbine's counter-pressure. This paper proposes a new method to evaluate the effect of wind on the output pressure of the turbine, as well as the effect of the combination of ambient temperature with the direct action of the wind. Finally, the results obtained are given in graph forms and a group of equations are proposed that allow attaining the output pressure of the turbine once ambient temperatures and wind speed are known. These expressions correlate in all cases with a mean error of 11.27% in 89.12% of the experimental data available, and they are considered, therefore, sufficiently precise for their use in thermal engineering. [ABSTRACT FROM AUTHOR]

Shell and tube heat exchangers (STHEs) are the most common type of heat exchangers. They are applied in many industrial facilities. The minimization of the costs of these heat exchangers is a key objective for both designers and users. The heat exchanger design involves complex processes, including selection of the geometric parameters and operating parameters. The traditional approach to design shell and tube heat exchangers is evaluating a number of different geometries of the exchanger to identify those that meet a requirement of heat and a set of geometric and operational constraints. However, this approach is slow, inaccurate and does not guarantee an optimal solution. In this paper is analyzed a procedure for designing heat exchangers and develops the economic optimization of the data by the method of simulated annealing. It was considered as the objective function the minimization of the total annual cost. For design optimization were considered as independent variables the inner diameter of the shell, the outer diameter of the tube and the spacing between the baffles. Also were considered to optimize two provisions or arrangements of tubes: in a triangle and a square. In this paper it is also presented an example of optimization of a heat exchanger. The results of the optimization using simulated annealing technique are compared with those obtained using particle swarm and genetic algorithms. [ABSTRACT FROM AUTHOR]

The environmental analysis of the "El Pinto" bakery it is addressed in the present paper. As a fist step a theoretical study of the systems involved in the process was carried out and the main environmental weakness were identified and quantified. Among the most important impacts there are the cleaning products, diesel, organic matter and the gas emissions. The solid materials are also impacting the ecosystem mainly polyethylene, cartoon and paper. The analysis concludes with a life cycle assessment of the technology. [ABSTRACT FROM AUTHOR]

The objective of this work is to combine the Life Cycle Assessment (LCA) and Hazard Analysis and Critical Control Points (HACCP) methodologies for the determination of risks that the food production represents to the human health and the ecosystem. The environmental performance of the production of pastas in the "Marta Abreu" Pasta Factory of Cienfuegos is assessed, where the critical control points determined by the biological dangers (mushrooms and plagues) and the physical dangers (wood, paper, thread and ferromagnetic particles) were the raw materials: flour, semolina and its mixtures, and the disposition and extraction of them. Resources are the most affected damage category due to the consumption of fossil fuels. [ABSTRACT FROM AUTHOR]

In this paper a kinetic and diffusive study regarding adsorption of ions Cu (II) on a sample of sugar cane bagasse ash is made. The results show that the second-order kinetic model better adjusts the experimental data than the Elovich and first-order kinetic model. The diffusive mechanism study shows that the diffusion in the liquid pellicle and in the micro-pores of the adsorbent prevail in the adsorption phenomenon. [ABSTRACT FROM AUTHOR]

Despite the current highly stringent international standards regulating the contaminating emissions to the environment, the Oil refinery of Cienfuegos is still generating liquid and gaseous emissions contaminating the environment. The construction of new units as part of the Refinery expansion leads to an increase of these emissions due to the lack of technologies for the reutilization of the sulphurous water. The objective of this paper is to propose a methodology for the integral management of the sulphurous residual water in the oil refining process, including the evaluation and selection of the most feasible technological variant to minimize the sulphur contamination of water and the resulting emissions during the process. The methodology is based on the ecological economy tools, allowing a comprehensible evaluation of six technological variants at the refinery of Cienfuegos. The Life Cycle Assessment was applied (ACV by its Spanish acronym), by means of the software SimaPro 7.1. It was evaluated through the Eco Speed Method, to minimize the possible uncertainty. An economic evaluation was performed, taking into account the external costs for a more comprehensive analysis, enabling, along with the ecological indicators, the selection of the best technological variant, achieving a methodology based on a comprehensive evaluation, and as a positive impact, the implementation of the chosen variant (V5), 98.27% of the process water was recovered, as well as the sulphur that recovered from 94 to 99.8 %, reducing the emissions from 12 200 to 120 mg/Nm3 as SO2. [ABSTRACT FROM AUTHOR]

In this paper, we propose a methodology for the obtaining of unsaponificable matter starting from the sugar cane filter cake, in the one that only ethanol 96 °GL is used as solvent. The wax is extracted of the mud with ethanol (with a purity of 96 °GL) by means of a leaching out process using a mud/ethanol ratio of 0.05 kg/L to 70 °C, atmospheric pressure, agitation speed of 700 rpm and extraction time of 2,5 hours. Under these conditions 86.21 % of extraction is obtained. Then, the obtained extract reacts with alcoholic NaOH to 70 °C during 75 minutes to atmospheric pressure and shaking to 200 rpm. The employment of the proposed methodology allows to obtain 1.942 g of impure unsaponifiable matter starting from 50 g of mud and 1.05 L of ethanol 96 °GL. [ABSTRACT FROM AUTHOR]

In this paper, a study of development of the stages of malting sorghum UDG-110 was performed, optimizing the process by studying the variables that influence it, such as NaOH concentration (%), soaking time and germination (h) at intervals from 0.1-0.5%, 24-36h and 48-72h respectively. The study of malted red sorghum was conducted, using the same variables. The results obtained in malting for white and red sorghum are similar, where the most influential variables in the response variables of quality malts are the concentration of sodium hydroxide but negatively, followed by germination time, the optimal values were 0.1% the concentration of sodium hydroxide, 12 hours and 72 hours soaking time and germination. It was combined sorghum malt and barley malt to make beer, showing that the addition of exogenous enzymes favors operating conditions. Finally, the starch extraction process was held on a laboratory scale, where the most influential and independent variables were analyzed, such as: type of sorghum, soaking time and concentration of SO2 solution, where it can be seen as white sorghum offered higher yields. Experimental design was used to conduct the experiences made in all studies, which were processed using Statgraphics Plus 4.1 software. [ABSTRACT FROM AUTHOR]

In this paper, a presentation is made of a study on the influence of some variations in the coefficient "ç" of the turn intensity, caused by manufacturing inaccuracies in the burner aerodynamic devices on the flame aerodynamics, the efficiency of the combustion process and, in general, on the operation of the whole facility. Moreover, the practical results of the paper, applied to unit # 3 of the "10 de Octubre" thermal power plant in Nuevitas, are also presented. [ABSTRACT FROM AUTHOR]

In this work is realized a discussion of all papers that the sugar cane production and other products derivates of sugar cane, that were published in the Centroazucar Review through 2000-2008 period. It is included one total of 472 scientific papers, 68 concerning the sugar cane productions, 28 with reference to de ethanol productions and 114 about other derivers' products of sugar cane. It is significant, the emphasis that it is made in the scientifically investigations concerning sugar machines with 84 Scientifics article and about welding activity with 33 articles publicities in the analyzing time. Also, there are contributing publications about the energetic and environmental problems with a total of 53 and 22 respectability. Finally, conclusions are elaborated on for future works. [ABSTRACT FROM AUTHOR]

This paper offers an analysis of different alternatives of supply of fuel to replace the necessities of heat and electricity in a process. As method for the analysis it has been used a combination of lineal programming method with an analysis of multiple regression and the Solver tool of the professional software Excel, being determined the less expensive combination of a mixture of four fuels for a energetically integrated system of production of raw sugar, pulp and paper of cane trash. The results arrives to demonstrate that the good solution is not always the rational way of satisfying the demand and as alternative the cost to pay reasonably for the solution but advantageous. [ABSTRACT FROM AUTHOR]

This work intends to obtain high yield bagasse pulps using moderate pulping conditions, including low sodium hydroxide charges (up to 3%). The adaptation of existing factories to the use of this minimum environmental impact process could be possible. The proposed final use for these pulps is corrugating board, mixed with recycled paper. Experiences were made in CICELPA, UIS, Colombia and PROCYP, UNaM, Argentina laboratories. Selectivity and reaction speeds of bagasse hydroalcoholic delignification in the high yield range increase with alkali charge, temperature and ethanol-water ratio. The global project aim is to manage an environmentally compatible and economically competitive technology of corrugating board production, taking profit of material and energy integration of sugar cane derived products. [ABSTRACT FROM AUTHOR]

In this paper are applied exergy method and the mixing of this with Pinch technology to a traditional Cuban bagasse boiler in order to find the irreversibility of the main subsystems. It is shown the nature of irreversibility, and the results reveal the real distribution of losses on the light of the second principle. This information could be used in following papers developing strategies based on more powerful methodological tools, so as to enhance the efficiency of this kind of equipment considering economical aspects. [ABSTRACT FROM AUTHOR]

This paper offers a computer program, which allows the automated selection of the tolerances of the transmission by cylindrical, conical and worm gears, used for the control as well as for the verification of these types of parts. The paper deals with errors and tolerances in toothed wheels and gears. Its main objective is the making of a tool that could be used by technicians, specialists and students majoring in Mechanics, guaranteeing the automated selection of the tolerances with a high level of reliability and speed. This undoubtedly, contributes to increasing productivity. [ABSTRACT FROM AUTHOR]

The objective of this paper is to show a methodology that allows finding the optimal behavior of a system, given a measure of effectiveness and a set of controllable variables. In the paper simulation techniques are combined with experimental design to produce a response surface, and after an optimization method is applied. A case study in the Cuban sugar industry is described. [ABSTRACT FROM AUTHOR]

The aim of this paper is to assess the current operating and safety conditions of biological treatment systems for wastewater in the centers of swinish and poultry breeding at Villa Clara Water Management Company, with the purpose of setting a group of organizational, technical and human measures that contributes to prevent contamination and minimize biological risks. In this way it can be guaranteed the protection to the workers, the facilities, community and the environment, to have a sure occupational atmosphere in the organization. As a result of the evaluation the factors that affect the operation of the biodigestion system and the security of the process are defined. [ABSTRACT FROM AUTHOR]

The Cuban sugar industry needs to implement methods to quantify the influence of technological process variables on the sugar cane industrial output as accurately as possible. It is needed to predict the behavior of its productive process in order to plan and optimize the use of the technical, financial and human resources to improve those technological variables that most influence on sugar cane industrial output. In this context the present paper seeks, firstly, to identify those technological variables that are correlated with the industrial performance and the main losses in the process, through the principal component analysis; and secondly, to quantify the effect of these variables on the sugar cane industrial output, losses in final molasses and bagasse losses, by using multiple regression models of log-log. The analysis of the results obtained by these statistical tools and their use to simulate different operating conditions of the process is shown. The developed models are useful to act from a technological point of view of the process and improve control over it. [ABSTRACT FROM AUTHOR]