LUNG CANCER AMONG TEXAS MALE OIL REFINERY WORKERS, 1976 - 1980 (CASE-CONTROL STUDY)

The apparent excess in the rate of lung cancer among the population of Texas coastal counties has prompted this study. The main objective was to assess the risk of lung cancer among employees of oil refining industries. Data collected by UTSPH and NCI were used for this research. A non significant overall low risk of lung cancer was observed among workers ever employed in oil refining (COR = 0.84). A lower but not significant risk of lung cancer was detected among the same workers when classified by their usual industry of employment (COR = 0.77). An overall non significant crosstime decline in the risk of lung cancer was observed among most of the occupational groups within the oil refining industry, with the exception of professional/technical and clerical/sales occupations where a non significant crosstime increase in the risk was observed. ^

Con el oficio en las manos. Las competencias como herramientas de continuidad en la trayectoria laboral : El caso de los ex obreros petroleros

En este artículo analizamos las transformaciones que la privatización de ypf trajo consigo en las trayectorias laborales de quienes eran sus trabajadores. En particular nos preocupamos por la relevancia que adquieren las competencias laborales en los caminos ocupacionales de los obreros que trabajaban en el sector mantenimiento y servicios de la refinería La Plata y que fueron desvinculados de la empresa debido a su desestatización. A partir de una investigación cualitativa en la que realizamos entrevistas en profundidad a ex obreros de esta unidad productiva, estudiamos las competencias que los trabajadores adquirían durante su desempeño en la refinería y el papel que jugaron las mismas en las trayectorias laborales posprivatización

Con el oficio en las manos. Las competencias como herramientas de continuidad en la trayectoria laboral : El caso de los ex obreros petroleros

En este artículo analizamos las transformaciones que la privatización de ypf trajo consigo en las trayectorias laborales de quienes eran sus trabajadores. En particular nos preocupamos por la relevancia que adquieren las competencias laborales en los caminos ocupacionales de los obreros que trabajaban en el sector mantenimiento y servicios de la refinería La Plata y que fueron desvinculados de la empresa debido a su desestatización. A partir de una investigación cualitativa en la que realizamos entrevistas en profundidad a ex obreros de esta unidad productiva, estudiamos las competencias que los trabajadores adquirían durante su desempeño en la refinería y el papel que jugaron las mismas en las trayectorias laborales posprivatización

Con el oficio en las manos. Las competencias como herramientas de continuidad en la trayectoria laboral : El caso de los ex obreros petroleros

En este artículo analizamos las transformaciones que la privatización de ypf trajo consigo en las trayectorias laborales de quienes eran sus trabajadores. En particular nos preocupamos por la relevancia que adquieren las competencias laborales en los caminos ocupacionales de los obreros que trabajaban en el sector mantenimiento y servicios de la refinería La Plata y que fueron desvinculados de la empresa debido a su desestatización. A partir de una investigación cualitativa en la que realizamos entrevistas en profundidad a ex obreros de esta unidad productiva, estudiamos las competencias que los trabajadores adquirían durante su desempeño en la refinería y el papel que jugaron las mismas en las trayectorias laborales posprivatización

Improvement of compatibility and stability on polyethylene-modified bitumen by use of an aromatic extra as compatibilizer.

Bitumen modification by polyethylene addition usually improves the mechanical properties of the binder and, therefore, the behavior in service of the bituminous mix: thermal susceptibility and rutting can be diminished, whilst the resistance to low temperature cracking may increase. To achieve this improvement it is necessary a good compatibility between the base bitumen and the polyethylene. Low compatibility between bitumen and polyethylene can lead to phase separation: the polymer- asphalt incompatibility translates into a deterioration of ultimate properties. The object of this research project was to determine if these problems can be diminished by using certain compatibilizer agents, e.g. an aromatic extract from the oil refinery. Compatibility and stability of the polyethylene modified bitumen were studied using conventional test methods and dynamic shear reometer (DSR). Blends of bitumen and polyethylene were prepared with neat bitumen (PMB) or bitumen with compatibilizer as component of the binder (PMBC) and then compared. The experimental results show that “colloid instability index”(IC) is a parameter that can be used to control the compatibility between bitumen and polyethylene. From polyethylene point of view, one of the parameters that govern is the “melt flow index” (MFI). Experimental results show that PMBC formulated with low IC bitumen and hi gh MFI lineal polyethylene can be considered as stable binder.

Real time optimization in chemical process: evaluation of strategies, improvements and industrial application.

The increasing economic competition drives the industry to implement tools that improve their processes efficiencies. The process automation is one of these tools, and the Real Time Optimization (RTO) is an automation methodology that considers economic aspects to update the process control in accordance with market prices and disturbances. Basically, RTO uses a steady-state phenomenological model to predict the process behavior, and then, optimizes an economic objective function subject to this model. Although largely implemented in industry, there is not a general agreement about the benefits of implementing RTO due to some limitations discussed in the present work: structural plant/model mismatch, identifiability issues and low frequency of set points update. Some alternative RTO approaches have been proposed in literature to handle the problem of structural plant/model mismatch. However, there is not a sensible comparison evaluating the scope and limitations of these RTO approaches under different aspects. For this reason, the classical two-step method is compared to more recently derivative-based methods (Modifier Adaptation, Integrated System Optimization and Parameter estimation, and Sufficient Conditions of Feasibility and Optimality) using a Monte Carlo methodology. The results of this comparison show that the classical RTO method is consistent, providing a model flexible enough to represent the process topology, a parameter estimation method appropriate to handle measurement noise characteristics and a method to improve the sample information quality. At each iteration, the RTO methodology updates some key parameter of the model, where it is possible to observe identifiability issues caused by lack of measurements and measurement noise, resulting in bad prediction ability. Therefore, four different parameter estimation approaches (Rotational Discrimination, Automatic Selection and Parameter estimation, Reparametrization via Differential Geometry and classical nonlinear Least Square) are evaluated with respect to their prediction accuracy, robustness and speed. The results show that the Rotational Discrimination method is the most suitable to be implemented in a RTO framework, since it requires less a priori information, it is simple to be implemented and avoid the overfitting caused by the Least Square method. The third RTO drawback discussed in the present thesis is the low frequency of set points update, this problem increases the period in which the process operates at suboptimum conditions. An alternative to handle this problem is proposed in this thesis, by integrating the classic RTO and Self-Optimizing control (SOC) using a new Model Predictive Control strategy. The new approach demonstrates that it is possible to reduce the problem of low frequency of set points updates, improving the economic performance. Finally, the practical aspects of the RTO implementation are carried out in an industrial case study, a Vapor Recompression Distillation (VRD) process located in Paulínea refinery from Petrobras. The conclusions of this study suggest that the model parameters are successfully estimated by the Rotational Discrimination method; the RTO is able to improve the process profit in about 3%, equivalent to 2 million dollars per year; and the integration of SOC and RTO may be an interesting control alternative for the VRD process.

Study of the thermal decomposition of petrochemical sludge in a pilot plant reactor

The pyrolysis of a sludge produced in the waste water treatment plant of an oil refinery was studied in a pilot plant reactor provided with a system for condensation of semivolatile matter. The study comprises experiments at 350, 400, 470 and 530 °C in nitrogen atmosphere. Analysis of all the products obtained (gases, liquids and chars) are presented, with a thermogravimetric study of the char produced and analysis of main components of the liquid. In the temperature range studied, the composition of the gas fraction does not appreciably vary. In the liquids, the light hidrocarbon yield increases with increasing temperature, whereas the aromatic compounds diminish. The decomposition of the solid fraction has been analysed, finding a material that reacts rapidly with oxygen regardless of the conditions it is formed.

A review of thermochemical conversion of microalgae

Microalgae are very effective microorganisms for CO2 capturing and a promising source of lipids for biodiesel as well as other interesting compounds. Many different ways of exploitation of these organisms are being tested. This work presents a review of the state of the art of the research and development of thermochemical conversion of microalgae with a special focus on pyrolysis and hydrothermal liquefaction. Aspects related to the type of reactors, the products obtained and the analytical applications are covered. The actual reaction scheme of pyrolysis of microalgae is extremely complex because of the formation of over hundreds of intermediate products. Various kinetic models reported in the literature and in a previous study with experimental validations are presented in this review to provide the current status of the study.

Thermogravimetry and Py–GC/MS techniques as fast qualitative methods for comparing the biochemical composition of Nannochloropsis oculata samples obtained under different culture conditions

Microalgae have many applications, such as biodiesel production or food supplement. Depending on the application, the optimization of certain fractions of the biochemical composition (proteins, carbohydrates and lipids) is required. Therefore, samples obtained in different culture conditions must be analyzed in order to compare the content of such fractions. Nevertheless, traditional methods necessitate lengthy analytical procedures with prolonged sample turn-around times. Results of the biochemical composition of Nannochloropsis oculata samples with different protein, carbohydrate and lipid contents obtained by conventional analytical methods have been compared to those obtained by thermogravimetry (TGA) and a Pyroprobe device connected to a gas chromatograph with mass spectrometer detector (Py–GC/MS), showing a clear correlation. These results suggest a potential applicability of these techniques as fast and easy methods to qualitatively compare the biochemical composition of microalgal samples.

Evidence of Intracrystalline Mesostructured Porosity in Zeolites by Advanced Gas Sorption, Electron Tomography and Rotation Electron Diffraction

The small size of micropores (typically <1 nm) in zeolites causes slow diffusion of reactant and product molecules in and out of the pores and negatively impacts the product selectivity of zeolite based catalysts, for example, fluid catalytic cracking (FCC) catalysts. Size-tailored mesoporosity was introduced into commercial zeolite Y crystals by a simple surfactant-templating post-synthetic mesostructuring process. The resulting mesoporous zeolite Y showed significantly improved product selectivity in both laboratory testing and refinery trials. Advanced characterization techniques such as electron tomography, three-dimensional rotation electron diffraction, and high resolution gas adsorption coupled with hysteresis scanning and density functional theory, unambiguously revealed the intracystalline nature and connectivity of the introduced mesopores. They can be considered as molecular highways that help reactant and product molecules diffuse quickly to and away from the catalytically active sites within the zeolite crystals and, thus, shift the selectivity to favor the production of more of the valuable liquid fuels at reduced yields of coke and unconverted feed.

Petroleum refinery streams as prospective reactor coolants : thermal stability investigations /

"Covering work by M. Macomber, W.W. West, J.G. Carroll, and R.O. Bolt."

Monitoring vibrations at U.S. Borax and Chemical Company potash refinery, final report /

U.S. Atomic Energy Commission Plowshare Program -- Cover.

Employment policies and labor mobility in a California sugar refinery.

Reprinted from the Monthly labor review (December 1919) of the Bureau of Labor Statistics, United States Department of Labor.

Community relations plan for the former Lawrenceville Refinery Site in Lawrence County, Illinois.

"Updated October 2003."

Former Premcor Refinery, Blue Island, Illinois : environmental investigations : progress update, Fall 2005 = Antigua Refineri a Premcor, Blue Island, Illinois : investigaciones ambientales : actualizacio n de progresos, octon o de 2005 /

Updates on-site environmental investigations by the PREMCOR Refining Group at the former Clark-Blue Island Refinery which began operations as the Great Lakes Refinery in the mid 1920s and continued operating at the Blue Island (Ill.) site until PREMCOR closed the refinery in 2001. Valero Energy Corporation purchased PREMCOR on Sept. 1, 2005.