1,819 research outputs found
Management by process as clean alternative for bioremediation project management
The purpose was to implement the management by process in the rehabilitation project of a zone polluted by hydrocarbons. There were implemented the eight steps in the problem solution and the study method of production management. There were identified deficiencies in the performance of the process and it was evaluated as steady and incapable. It was simulated and improvement proposition, where the results showed its feasibility. It was diminished the 53.33 % of the productive cycle time and its stability was achieved. There were diminished the costs in a 10.57 %. It was contributed to the achievement of cleaner productions
Procedure for Technological Diagnosis of Oily Residuals Management in Cubans Distributed Generation Power Plants
In Cuba, more than 50 % of the electricity generation capacity is based on small-scale distributed power plants, which
guarantee the energy supply-demand from fossil fuels. Several negative environmental impacts are associated with this,
including contamination by oily residuals. The purpose was to diagnose oily residuals management in Cubans distributed
generation power plants from a technological approach. Ten generating power plants from Cienfuegos territory were selected
as a case study. A methodological procedure, supported in the general method of problem-solving was designed. The
environmental audit was used as a fundamental tool for the verification of technical requirements regarding the containment,
collection, evacuation, treatment, and final disposal of oily waste. For deployment of causes identified as evidence of auditory,
failures modes and effects analysis (FMEA) were used. Hydrocarbon concentrations at sampling points in the external
environment frequently exceeded the threshold. Hydrocarbon spills, clogging and waste load increased in the treatment system,
were the most frequent failure modes and could manifest themselves from the occurrence of more than 150 causes. From this
group, a set of common causes inherent to each power plant was identified. A package of corrective actions was designed,
which constituted conceptual ideas for improving environmental performance. The procedure was generalized to other power
plants in the country, contributing to sustainability in the generation of electricity in Cuba
Planktonic cyanobacteria from the Abreus Reservoir, Cienfuegos, Cuba
The study of the cyanobacteria that make up the phytoplankton community of reservoirs is very important due to the production of toxins by some phytoplankton taxa. The composition and abundance of cyanobacteria and their relationship to physicochemical variables was determined during six months (March, April, June, September, November and December) in 2018 at five stations in the Abreus Reservoir, which is located in the south center of the Cienfuegos province (Cuba). Eleven new taxa were observed in the reservoir grouped into seven families, 14 genera, and 34 species. The toxigenic genera Microcystis and Raphidiopsis were observed at all collection points throughout the year, presenting a potentially persistent toxicity threat in this reservoir. Semi-accumulative blooms were reported in September. Microcystis sp. and Raphidiopsis sp. were the most abundant genera during observed blooms. The abundance of some cyanobacterial genera, including Microcystis, Aphanocapsa, Raphidiopsis and Dolichospermum, were strongly correlated with water temperature and transparency. Microcystin values are reported for the first time in Abreus Reservoir
Procedimiento para la gestión de los impactos ambientales negativos asociados a la recuperación de materias primas en Cienfuegos, Cuba
Recycling is a prioritized activity in Cuba. The goal was to implement a procedure to manage the negative environmental impacts associated with key processes of Recovery Raw Materials Cienfuegos Enterprise. The procedure was constructed using the proposal of the Andalusian Institute of Technology for process management and the eight steps in solving problems. Under the principle of methodological convergence management tools were combined. The environmental impacts were assessed using the GAIA software version 1.0, the criteria proposed by the Methodological Guide to Environmental Impact Assessment of Conesa. Was took in to account. 97 negative environmental impacts were identified, severe and moderate integrated the 80.41 % of them. Physic-chemist was the more impacted environmental factor with 50.52 %. The non-metallic subprocess was the most impactful, with 50 % of the total negative severe impacts and 34 % of moderates. The main associated causes were identified and an intervention plan of 35 measures based on the principles of cleaner production was designed. The results contribute to achieve the management of the negative environmental impacts of the entity and sustainability of recyclin
Bioremediation of Hydrocarbon-Polluted Soil: Evaluation of Different Operative Parameters
The bioremediation of soils polluted with hydrocarbons demonstrated to be a simple and cheap technique, even if it needs a long time. The current paper shows the application of statistical analysis, based on two factors involved in the biological process at several levels. We focus on the Design of Experiments (DOE) to determine the number and kind of experimental runs,
whereas the use of the categorical factors has not been widely exploited up to now. This method is especially useful to analyze factors with levels constituted by categories and define the interaction
effects. Particularly, we focused on the statistical analysis of (1) experimental runs carried out at laboratory scale (test M, in microcosm), on soil polluted with diesel oil, and (2) bench scale runs (test B, in biopile), on refinery oil sludge mixed with industrial or agricultural biodegradable wastes. Finally, the main purpose was to identify the factor’s significance in both the tests and their potential interactions, by applying the analysis of variance (ANOVA). The results demonstrate the robustness of the statistical method and its quality, especially when at least one of the factors cannot be defined with a numerical value
Zanjas de infiltración: opción para mitigar la erosión hídrica en la playa Rancho Luna
The water erosion of Rancho Luna beach requires engineering solutions based on the principle of
minimizing runoff from rainwater to the beach. The aim was to design an infiltration trench as an
option to mitigate the erosion. The design complies the requirements established for infiltration
trenches. It was corroborated that its dimensions allow storing, infiltrating and evacuating the
water of the design rain to the degree of protection required. The results were taken into account
by the environmental authorities and the operator of the beach for making decisions in the
framework of the ordering process that is realized in the coastal zone. As well as in the
projection of solutions in correspondence with the investment process that must be undertaken
Auditoría del manejo de residuos oleosos en un grupo electrógeno de diésel
The generation of electricity has associated negative environmental impacts among
which is the contamination by oily waste. The purpose was to audit the management of
the oily residuals of a diesel generator and to propose corrective actions for the findings.
The eight-step procedure was used in solving a problem. The audit criteria were
established and, as evidences, the treatment organs were diagnosed, the receiving body
and the oily water disposed were sampled. The concentration of hydrocarbons and fats
exceeded the established limits. Hydrocarbon spills, increased system load and clogging
were the main failure modes. A plan of 27 corrective actions was designed, which
constituted conceptual ideas to improve environmental performance. The procedure can
be generalized to other sets and thus contributes to sustainability in the distributed
generation of electrical energy
Gestión de riesgos laborales en proyectos de rehabilitación ambiental de zonas contaminadas con hidrocarburos
The present Cuban Environmental Strategy identifies the contamination of crude oil wastes as a problem with particular managemental characteristics, which is managed by the implementation of environmental rehabilitation projects. The goal of this search was to
manage the working risk factors dealt with the rehabilitation projects in hydrocarbon contaminated areas. The project “Comprehensive environmental rehabilitation in Punta Majagua, Cienfuegos, Cuba” was selected as a case study. To achieve this goal, a procedure using the methodological convergence of diverse tools was implemented. Different techniques of managemental processes, quality and working
risks were used as well as several instruments for gathering information. 50 working risk factors were identified associated to all processes
and 40 % of them were assessed as critical. The most dangerous processes were the bioremediation campaign and the creation of
technical and logistic capacities. Some indicators that revealed the efficacy and efficiency of the strategy in risk’s mitigation were identified. The workers’ satisfaction state at the workplace after this intervention was assessed as positive, except for the dimensions of physical working conditions and salary. These results confirm the right management of risk factors in this project as its possibility of generalizing experience to get safe working standards thus contributing to the
achievement of clean productions
Redesign and structural optimization of a rotary vacuum dryer (RVD) powered with vapor
La empresa Corteva Agriscience es una multinacional encargada de la producción de herbicidas, fungicidas, entre otros productos relacionados con el agro. Actualmente se ubicada en el municipio de soledad, Atlántico. Planteó una problemática respecto a los tiempos de secado durante la elaboración de Mancozeb (fungicida), que toma alrededor de 3 horas y quieren reducirlo al menos a 2 horas y 30 minutos. El secado se realiza por medio de un RVD (Rotary Vacuum Dryer) el cual está conformado por una carcasa estática cubierta por una chaqueta y un eje rotativo que cuenta con cintas y ramificaciones, el proceso es llevado al vacío para disminuir el punto de ebullición del agua, dado que el material a secar no puede superar los 80°C. El fenómeno que rige el proceso es la transferencia de calor ocasionada por el vapor que fluye a través de la chaqueta y el eje. La empresa como posible solución propone aumentar la presión del vapor través del eje, pero teme por los esfuerzos ocasiona dicho cambio.
Durante el planteamiento de alternativas, analizamos la sugerida por la empresa y mediante cálculos de transferencia de calor apreciamos que el coeficiente global de transferencia de calor se mantiene alrededor de unos 1.95 kW/m2k por más significativo que sea el cambio en la presión, por lo cual los tiempos serán similares. Por otro lado, haciendo una revisión exhaustiva del estado de la técnica proponemos hacer pequeños cambios al equipo teniendo en cuenta el factor económico, entre ellos la implementación de sellos mecánicos para mantener la hermeticidad dentro del equipo y evitar las infiltraciones, modificar las condiciones del fluido que pasa a través del eyector para mejorar el vacío, implantación de rodamiento lineal en un extremo y conos truncados para el soporte de las ramificaciones. Por último, el cambio del eje o modificación de la geometría del eje, para ampliar el área de transferencia de calor sin afectar significativamente el volumen de trabajo, muy costosa.Corteva Agriscience Company is a multinational that produced of herbicides, fungicides, among other products related to agriculture. Currently located in the municipality of Soledad, Atlántico. They have a problem regarding the drying times during the production of Mancozeb (fungicide), which takes around 3 hours and they want to reduce it to at least 2 hours and 30 minutes. Drying is carried out by means of an RVD (rotary vacuum dryer) which is made up of a static casing covered by a jacket and a rotary axis that has tapes and branches; the process is carried out under vacuum to decrease the boiling point of water, since the material to be dried cannot exceed 80 ° C. The phenomenon that governs the process is the heat transfer caused by the steam that flows through the jacket and the shaft. The company as a possible solution proposes to increase the pressure of the vapor through the axis, but the time caused by the efforts causes such a change.
During the proposal of alternatives, we analyze the one suggested by the company and through heat transfer calculations we appreciate that the global coefficient of heat transfer remains around 1.95 kWm2kno matter how significant the change in the pressure, so the times will be similar. On the other hand, making an exhaustive review of the state of the art, we propose to make small changes to the equipment taking into account the economic factor, including the implementation of mechanical seals to maintain the tightness within the equipment and avoid infiltrations, modify the fluid conditions that passes through the ejector to improve the vacuum, implantation of a linear bearing at one end and truncated cones to support the branches. Finally, the change of the axis or modification of the axis geometry, to expand the heat transfer area without significantly affecting the work volume, very expensive
Erosión hídrica del sector de playa del hotel Ancón, Sancti Spíritus, Cuba.
The purpose of this work was to assess the contribution of the storm drainage system of the
Ancon hotel over the erosion of its beach sector and to propose a plan of corrective measures for
their mitigation. A procedure based on the eight steps in the solution of a problem was designed,
complemented with specific methodologies and tools. The water origin of the erosion was
predominating, with manifestations of the gully erosion type. Rain erosive power, enhanced by
technical and organizational deficiencies in the storm drainage system, as well as the influence of
the erodibility of the land and constructed elements, increases flow and velocity rates. A
corrective action plan to mitigate erosion based on hydraulic and coastal engineering solutions
was designed
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