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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]

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]

In search of native cellulase-producing microorganisms, collected from lignocellulosic waste in Ecuatorian Andes, Amazon region, and in Antarctica, 17 sporulating strains were found. These strains and the cocktails obtained from them were used in assays to measure glucose concentration produced from carboxymethylcellulose, crystalline cellulose and filter paper units (FPU). The obtained values were that only the cocktail from Bacillus sp. collected at a "panela" artisan factory produced glucose concentrations that might be of interest, after the cellulases degraded all substrates: carboxymethylcellulose, crystalline cellulose and filter paper. The amount of glucose liquor obtained in the best assay was measured in HPLC, producing 3.45 mg/ml of glucose after the action of endo-beta-glucanase and 1.8 mg/ml of glucose in presence of exo-glucanase. The amount of filter paper units produced in vitro were 0.0073 FPU. However, the study found that, since the Payback Period for the investment was 6 years, it would not be recommendable to invest in a production plant with these cocktails. Due to this, is recommended to continue the research with this strain of Bacillus sp. to improve the dynamic indicators. [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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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, the study of the possibilities of the efficient use of forest residuals as raw materials, for the production of bioenergetics that guarantees the operations of a plant for the recycling of plastic residuals is exposed. In the study, a conceptual model and the procedures for the assimilation of technologies of bioenergetic production, reported in previous works, is validated (Muto et al., 2016). Due to their significance, it is considered the uncertainty to the future changes with emphasis to the growth of the demand of capacities of prosecution of urban solid wastes (USW) and the readiness of the raw material. Suitable values of initial investment capabilities are determined for a first step forward so that a second stage investor that increases capabilities must be run at 6 years for initial investment executed capabilities. The first investment will recover in 2.8 years. [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]

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 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, 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]

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 prices of ammonium salts which are used in the torula yeast production technology are very high nowadays. In the other hand, this technology has very high energy costs which are consumed by blowers in fermentation, separators machines and in the concentration and drying of yeast. In this paper, different technical alternatives are analyzed for reducing the production cost of torula yeast, through changes in production inputs, electric motors and the replacement of a portion of the fuel used for drying by biogas. Then, the economic feasibility in both currencies is evaluated for practical application. [ABSTRACT FROM AUTHOR]

In this paper, an analysis of the investment task and projection is performed, as well as technical-economical analysis of the possibilities of production Biodiesel on an industrial scale in "Heriberto Duquesne" Molasses Company. An extensive literature search on the subject of biofuels, and biodiesel in particular was conducted, with a view of selecting the most feasible variant of production and raw materials to carry out the process, where the mud oil, ethyl alcohol and sodium ethoxide catalyst were the most attractive variants. The essential part of the job is the investment task and projection, followed by sizing the equipment for the production of Biodiesel plant, starting from the residual filter cake which provides the Molasses Company. Besides, material balances and energy are analyzed, in addition to equipment design of the chosen section, as well as their technical - economical analysis. [ABSTRACT FROM AUTHOR]

In this paper, two technological alternatives were analyzed for the production of ethanol in order to diminish the vinasse volume at the exit of the distilling column. Also environmental effects and energy efficiency of the process were discussed, making a proposal for the treatment of residuals. A simulation model was elaborated in Microsoft Excel using process analysis techniques. By means of mass and energy balances, actual process behavior and its technological changes were simulated. The alternatives proposed of adding a bottom reboiler to the distilling column and to recirculate vinasses to the molasses dilution tank decrease the flow obtained at the bottom of the distilling column, showing the best results when combining the alternatives. The alternatives are economically feasible, they obtain higher IRR (Rate of return on investment) than the interest rate used, and the investment is recovered in less than four years, showing liquidity. [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]

Process Integration (PI) is a tool that for over forty years has demonstrated its strength to provide optimal solutions to complex problems. The interaction of exchange systems of energy and water networks is a typical case of such problems. The gradual increase in the consumption of water and energy has determined the development of methodologies that take into account the simultaneous integration of these resources. This paper aims to present a literature review related to the simultaneous integration of water and energy. First, general items related to this research field are presented, emphasizing the approaches to simultaneous integration (Pinch Analysis and Mathematical Programming). Some recent cases of studies, demonstrating the strength of these tools mainly focus to sugar industry, are also presented. Finally some of the challenges to be faced by the simultaneous integration of water and energy for the diversification of the Cuban sugar industry are presented. [ABSTRACT FROM AUTHOR]

Blocking Contours are a graphical method. By means of this technique, the gear designer obtains the values of the correction coefficients, which meets the undercutting geometric constraints, contact ratio, interference and teeth pointing. This paper presents a mathematical model that allows non-interactive construction of blocking contour in the field of cylindrical external gears with asymmetric teeth. For this purpose, the equations defining the mentioned restrictions are modified and it is set the sequence in which they should be calculated. This makes possible the analytical use of the limits of blocking contour for establishing the dependence between the geometric parameters of these transmissions, thereby facilitating synthesis work. [ABSTRACT FROM AUTHOR]

The biorefineries concept from renewable sources has gained much attention in recent years because they improve sustainability with regard tofossil fuel refineries that are limited by the depletion of petroleum reserves. In this perspective, the production of ethanol from sugar cane bagasse is highly attractive because it reduces the fossil fuels consumption, the energy costs and the greenhouse gases emission. In this context, this paper aims to develop an optimal model design of an ethanol plant, considering bagasse pretreatment stages for subsequent simultaneous saccharification and fermentation (SSF). SSF variant, as its name suggests, has the advantage that enzymatic hydrolysis and fermentation stages are simultaneously carried out on the same equipment, obtaining directly the ethanol as a main product. The proposed approach is based on a mixed integer linear programming model which is optimized by GAMS-CPLEX package. [ABSTRACT FROM AUTHOR]

In this paper, the assessment results accomplished in different processes of the galvanic industry are presented and it is taking into account the application of good practices and measures of Cleaner Production. The main critical points in the processes of metallic coating were identified; and the characterization of the effluents generated by the installation is done. A number of technological changes in the processes are proposed, as well as the introduction of cleaner production measures which contribute to increase the efficiency and safety of processes, reduce risks and improvements to internal operations. It provides advantages of economic, environmental and social nature for the galvanic industry due to the minimizing of the impacts on environment, because the sewage and its pollutant load are reduced. Besides, we can save water, energy and raw materials. The economic evaluation showed the feasibility of applying the Cleaner Production (PML) measures proposed with a Net Present Value (NPV) of $109 696.26, and an Internal Rate of Return (IRR) of 64 % value and payback period lower than two years. [ABSTRACT FROM AUTHOR]

In this paper, we presented the main problems that entail an inadequate distribution of loads on trucks and we described in detail a methodology for determining the proper position, which concludes with the completion of the installation diagrams. The methodology was obtained from the solution of the particular case of a tank of liquefied petroleum gas (LPG) of 14'000 liter on a DAF CF 75.310 truck. Another result of this work is a software which allows to determine the exact position it should be the gravity center of the load relative to the front axle and the reactions on each axis, with the possibility of evaluating different variants. [ABSTRACT FROM AUTHOR]

This paper presents how the design approaches with high level of flexibility can reduce the additional costs of the strategies that apply overdesign factors to consider parameters with uncertainty that impact on the economic feasibility of a project. The elements with associate uncertainties and that are important in the configurations of the process integration under a biorefinery scheme are: raw material, raw material technologies of conversion, and variety of products that can be obtained. From the analysis it is obtained that in the raw materials and products with potentialities in a biorefinery scheme, there are external uncertainties such as availability, demands and prices in the market. Those external uncertainties can determine their impact on the biorefinery and also in the product prices we can find minimum and maximum limits that can be identified in intervals which should be considered for the project economic evaluation and the sensibility analysis due to varied conditions. [ABSTRACT FROM AUTHOR]

Air Conditioning with renewable energy is a key issue in the region's energy policy. The high temperatures usually attributed to climate change and the increase of the standard of living in society continues increasing energy demand in order to establish the conditions for thermal comfort in buildings. Solar air conditioning, although it contains a mature technology, its level of market introduction and acceptance by designers of buildings is exhaustive. This paper discusses the feasibility of these projects, identifies non-technological type barriers that hinders such use and implementation of solar energy for air conditioning systems, and finally, it approaches some criteria and recommendations to overcome these obstacles. [ABSTRACT FROM AUTHOR]

In this paper, the mathematical modeling and simulation of the automatic control of the quintuple effect of evaporation of a sugar mill "El Palmar" in Venezuela is made. The multiple effect consist of 5 evaporators Robert type, with equal characteristics, connected in series. Starting from the desired operating conditions and control requirements: level in each evaporator vessel, cane syrup concentration and pressure in the fifth evaporator vessel using mass balances, balance on solids for each evaporator and energy to the barometric condenser is present at the output of the fifth vessel, the nonlinear model of the process is obtained, resulting in a system of multiple inputs and multiple outputs, with strong interactions between variables. In the design of the system of the automatic process control, we are interested in maintaining the variables that characterize the performance of it and they are regulated in an operating point; we proceed to linearize the model around an equilibrium point, resulting in a new model in terms of the variables variations around an environment from that point. Then, it is processed the model obtained in terms of input and output relations, based on the characterization of it in terms of variables and transfer relationships in the complex frequency domain. Finally, the evaporation process is simulated, establishing the adequacy of the model to the real process. [ABSTRACT FROM AUTHOR]

In this paper, the conditions for obtaining an anionic exchanger based on the chemical modification of the fibrous fraction of bagasse by etherification in basic medium are studied. It evaluates the influence parameters concentration of sodium hydroxide, the molar ratio cellulose/diethylaminoethylamine hydrochloride and the reaction time in the substitution. In each case a degree of substitution estimated by determining the nitrogen content was obtained. It has been demostrated that the product removed 40-60 % of color in sugar solutions, therefore can be used in the sugar industry for the removal of ionic compounds. [ABSTRACT FROM AUTHOR]

In this paper, the modeling and analysis of one tower Workover Rig belonging to a maintenance facility for oil and gas wells is presented. When performing the maintenance of this tower, it is detected that one of the elements of the structure has some deformation. It was decided not to put it into operation and submit it to research. The modeling of invariants as well as ways of modeling soil structure interaction is discussed. It was necessary to determine the material properties with the performing of test of some samples taken on two components of the tower. The structural behavior of the tower to operating loads are then studied, proving that the effect of the deformed element in the structure is not significant for the stresses to which are subject. [ABSTRACT FROM AUTHOR]

This paper determines and studies, analyzes and elaborates and classifies and categorizes the main qualitative techniques for hazards identification and assessment in chemical industrial processes. It specifies that these techniques base their effectiveness both, on analytical estimation processes and on the safety managers-engineers ability. It enumerates also those that present a bigger use frequency as well as the dangers that identify and the results that they give. Their use is linked, in function of the complexity level of the analysis technique, with the different stages of the life of industrial projects / processes. [ABSTRACT FROM AUTHOR]

Some solid fuels which are very pollutant and with low value could be transformed into a clean gas that could be used in many industrial applications for its physical properties and for being easy transported. Then, electricity generation is one of the most important applications. In this case, electricity could be generated, cleanly and efficiently, through the use of synthesis gas that replaces the natural gas in a combined cycle (Biomass Integrated Gasification Combined Cycle (BIGCC)). In this paper, we carry out an economic feasibility study of the project about the implementation of Biomass Integrated Gasification Combined Cycle (BIGCC) in a 10000 tc/d sugar mill from bagasse gasification in order to demonstrate, from the economic point of view, the possibility of investment in this kind of technology considering the current conditions of Cuban sugar industry. Later, a sensitivity analysis is presented to show first, the break-even point associated to the project and second, the variations of financial indicators due to changes on the total amount of investments, which is a very helpful element for making right decisions in the project investment process.. [ABSTRACT FROM AUTHOR]

The decrease of the fossil fuels stocks and environment deterioration have required the searching of renewable sources, among them, the lignocellulose biomass (LCB) constitutes a safe and inexhaustible alternative as the base for the future industry according to the modern concept of biorefinery. The LCB has a very complex structure where their components are strongly bonded, that is why their separation requires several stages of the consumption of chemical and energy. The microwave is one of the new technologies used for the conversion of the LCB into products of high added value. The objective of this paper has been to explore the influence of the treatment with microwaves on the hydrolyzed bagasse in order to get cellulose pulp. This material is treated with different concentrations of sodium hydroxide (14, 17 and 20 %) and microwaves exposure times (15, 30 and 45 minutes). The temperature (88 °C), the particle size, the solid to liquid ratio and the microwaves power are kept constants. The solid phase is characterized by means of its chemical composition, while the liquid phase is characterized by means of the contents of total sugars. The higher value of cellulose content (83.2 %) is obtained with 20 % of sodium hydroxide at 30 minutes of microwave exposition and 88 °C, which is comparable with the results obtained by the traditional pulping method at 160 °C. [ABSTRACT FROM AUTHOR]

This paper presents a state-of-art-review of the available studies and techniques that allow the identification, evaluation and control of the hazards that can appear in the different stages of the life of industrial processes: design, construction, start-up and normal operation, process modifications and dismantling or abandonment of the facilities. It is also evidenced that the application of these identification techniques of hazards in the chemical processes allows to prevent the accidents that can happen in the industrial facilities and to assure the productivity of the same ones. [ABSTRACT FROM AUTHOR]

There is currently an effort to achieve economic feasibility of using lignocellulosic biomass as a new source of sugars for ethanol production. The infeasibility of these processes is mainly due to the cost of enzymes and no use of co-products that are generated in the pretreatment of biomass. The technical, economic and environmental assessment of different biorefinery schemes is complicated by the uncertainty in areas such as raw material to be used, the prices of energy and the product, investment costs, operation and risks of new technologies. In this paper, the guidelines show how process integration and assessment of coproducts in the biorefinery scheme leads to the feasibility of the processes that use biomass for biofuels are given. A scheme of integrated processes that exchange materials and energy resources is displayed, the scheme refers to the cane industry sugar generated as major products juice, bagasse and molasses and other products derived processes in annexes found among torula, biogas, CO2, furfural, lignin, and electricity on the basis of environmental management. [ABSTRACT FROM AUTHOR]