Engineering Commons^™

Breves Notas Sobre Modelado, Francisco J. Valdes-Parada

Francisco J. Valdes-Parada

No abstract provided.

Subsidies For Energy Efficiency Improvements: Theory And Practice, Theodoros Zachariadis

Theodoros Zachariadis

No abstract provided.

Wpływ Dużej Spalarni Odpadów Przemysłowych I Niebezpiecznych Na Jakość Powietrza, Robert Oleniacz, Lidia Rusztowicz

Robert Oleniacz

Waste incineration causes unavoidable pollutant emissions to atmosphere and thus negative impact on air quality, but scale of the influence is often exaggerated. In the paper computation results of the atmospheric dispersion of pollutants were presented for one of the largest industrial and hazardous waste incineration plant existing in Poland (processing capacity: 3 ton per hour). These results confirm the fact that the incinerator meets the requirements of best available techniques (BAT) for the waste incineration and its impact on air quality is relatively small. This effect is caused mainly by proper operation of the rotary kiln incinerator, high efficiency …

Analiza Wpływu Planowanego Zakładu Termicznego Przekształcania Odpadów Komunalnych Na Jakość Powietrza W Krakowie, Robert Oleniacz, Maria Pilch

Robert Oleniacz

Construction of the Municipal Solid Waste Incineration (MSWI) plant is considered optimal in the Programme of Management of Solid Waste in Krakow as well as in proposed scenarios of Municipal Waste Management. Evaluation of impact of the incineration plant with a capacity of 255000 tons per year on air quality in Krakow is presented in this work. The evaluation is based on assumption that air pollutant emissions from the incinerator will be at the highest allowed level resulting from emission limit values for waste incineration plants with operation time each of two planned lines 7500 hours per year. Calculation results …

Multivariate Analysis Of Groundwater And Soil Data From A Waste Disposal Site, Kevin G. Mumford, John F. Macgregor, Sarah E. Dickson, Richard H. Frappa

Sarah E Dickson

Environmental site investigations often involve the collection and analysis of hundreds of samples producing data sets that contain thousands of data points, which are difficult and time consuming to analyze. Consequently, investigators often focus on key surrogate parameters for site characterization and remedial action planning and assessment, which results in a large portion of the data collected remaining unused. This study presents the application of principal component analysis (PCA) as an efficient statistical technique to examine large environmental data sets through highlighting patterns in a reduced-variable space. In this work, PCA was applied to ground water and soil data collected …

Assessing The Possibility Of Corrosion Occurrence In Metallic Stacks Caused By Hydrochloric Acid, João F. Gomes

João F Gomes

This article presents a simple method to estimate the possibility of corrosion in metallic stacks and surfaces due to hydrochloric acid deposition from stack gases, based on the HCl content in gases and also the flue gas temperature

New Technologies For Effective Forest Fire Fighting, João Gomes

João F Gomes

Efficient fire extinction with water could be greatly improved by using superabsorbent polymers, added to the water used for fire fighting, or sprayed over surfaces of combustible materials in order to protect them from fire. Specially developed superabsorbent polymers such as acrylamide/2-acrylamide-2-methyl-propane-sulphonate (AA/AMPS) seem to be particularly efficient for this purpose. In terms of water absorption, the experimental tests performed, showed that the optimal composition of this polymer is 30:70 AMPS versus AA, using 0.5% of bis-acrylamide (BA) as crosslinking agent.

Deriving An Indoor Environmental Index For Portuguese Office Buildings, João F. Gomes

João F Gomes

The EC issued a Directive in 2002 aiming to reduce the energy consumption of buildings, which was adopted by the EU member states and came into force in 2006. Portugal adopted it by issuing law decrees in 2006 which considered not only the energy saving aspects but also additional specific measures aiming to protect indoor air quality (IAQ). This new legislation is now being enforced and it will be necessary to define compliance acceptance levels for the prescribed indoor air limits. The use of comfort or environmental indexes could be of considerable help in order to ameliorate the evaluation of …

The Importance Of Considering Building Downwash When Assessing The Need To Heighten Stacks Of Existing Small And Medium Sized Industries, João F. Gomes

João F Gomes

No abstract provided.

Measurements Of Indoor Air Pollutant Levels In A University Office Building, João F. Gomes

João F Gomes

This work consisted of a series of determinations performed in typical rooms of a building belonging to the Technical University of Lisbon, which is located in a central urban area of Lisbon. The main objective was to evaluate the Indoor Air Quality (IAQ) of the rooms so that further corrective measures could be taken if unsatisfactory IAQ levels were to be found. Correlations were derived, between indoor and outdoor pollutant concentrations, in order to assess the existence of contaminations coming from outside. Also, correlations were derived between total volatile organic compounds (VOC) concentrations and specific individual organic species measured in …

Reflections On The Use Of The Mccabe And Thiele Method, João F. Gomes

João F Gomes

This paper reflects on the continuity of teaching the McCabe and Thiele method on chemical engineering courses for understanding the vapour-liquid equilibrium phenomena involved in distillation. Some exercises comparing the results obtained by this method as well as by other accurate analytical methods are presented and solved, as they are taught in ISEL courses. Because of its accuracy and easiness of use, and also because of the fact as this method allows an easy visualisation of the whole operation itself, the McCabe and Thiele method continues to be widespread used and students show a remarkable adherence to it.

Analysis Of Mass Transport And Reaction Problems Using Green's Functions, Francisco J. Valdes-Parada

Francisco J. Valdes-Parada

A methodology to solve typical problems of mass transfer and chemical reaction engineering in terms of Green’s functions is presented. The fundamental idea consists on analytically inverting a differential operator by means of the solution of a boundary value problem associated to the original transport and reaction problem. The dependent variable is expressed then as function of the solution of such associated problem, which is the Green’s function. Among the advantages that this methodology presents are the smoothing of round-off errors as well as the exact incorporation of boundary conditions. A mandatory requirement for the application of this methodology is …

Boundary Conditions For The Transport Between Multiphase Media, Francisco J. Valdes-Parada

Francisco J. Valdes-Parada

The corresponding boundary conditions, for momentum, heat or mass transfer, between two regions is an indispensable element in the development of models that describe transport in heterogeneous systems. For this reason, it is common to find in the literature boundary conditions that may be adequate for describing a particular phenomenon, but were obtained on an empirical basis and, frequently, include unknown coefficients.

The above has caught the attention of several authors that, in the last three decades, have presented methodologies that allow obtaining boundary conditions maintaining a close relation to the physics of the studied phenomenon. Among the various reported …