The Modeling of CO2 Removal From a Gas Mixture by 2-amino-2-methyl-1-propanol (AMP) Using the Modified Kent Eisenberg Model

In this paper, the solubility of CO₂ in AMP solution has been measured at temperature range of 293, 303, 313, and 323 K. The amine concentration ranges studied are 2.0, 2.8, and 3.4 M. A solubility apparatus was used to measure the solubility of CO₂ in AMP solution on samples of flue gases from thermal and central power plants of Esfahan Steel Company. The modified Kent Eisenberg model was used to correlate and predict the vapor-liquid equilibria of the (CO₂ + AMP + H₂O) system. The model predicted results are in good agreement with the experimental vapor-liquid equilibrium measurements.     

CFD and experimental studies of room fire growth on wall lining materials

CFD simulation and experimental tests have been carried out to study the room corner fire growth on combustible wall-lining materials. In the CFD simulation, the turbulent mass and heat transfer, and combustion were considered. The discrete transfer (DT) method was employed to calculate the radiation with an absorptivity and emissivity model employed to predict the radiation property of combustion products including soot, CO₂ and H₂O, which are usually the primary radiating species in the combustion of hydrocarbon fuels. The temperature of the solid boundary was determined by numerical solution of the heat conduction equation. A simple and practical pyrolysis model was developed to describe the response of the solid fuel. This pyrolysis model was first tested against the Cone Calorimeter data for both charring and non-charring materials under different irradiance levels and then coupled to CFD calculations. Both full and one-third scale room corner fire growths on particle board were modelled with CFD. The calculation was tested with various numbers of rays and grid sizes, showing that the present choice gives practically grid- and ray number-independent predictions. The heat release rate, wall surface temperature, char depth, gas temperature and radiation flux are compared with experimental measurements. The results are reasonable and the comparison between prediction and experiment is fairly good and promising.     

Fuel characteristics of gasified coconut shell in a fluidized and a spouted bed reactor

In this study, an attempt has been made to gasify coconut shell in a fluidized and a spouted bed reactor. The effects of the gasification temperature on individual gas components, their yields and heating values for both types of beds have also been studied. The fluidized bed appears slightly superior to the spouted bed both in respect to heating value and gas yield over the temperature range studied.     

A 7th–grade science project casts doubt on the standard explanation of the Gaussian plume model for seepage through soil

The Gaussian plume model is traditionally used to describe the movements of contaminants through carrier media. In two dimensions, the model is mathematically derived from a stochastic representation of sequential collisions between contaminant particles and the particles of the carrier medium. The corresponding model for three dimensions is derived by analogy. We show with a simple experimental system that this deduction by analogy is faulty.     

A heuristic algorithm for solving flexible job shop scheduling problem

This paper deals with the flexible job shop scheduling problem with the objective of minimizing the makespan. An efficient heuristic based on a constructive procedure is developed to obtain high-quality schedules very quickly. The algorithm is tested on benchmark instances from the literature in order to evaluate its performance. Computational results show that, despite its simplicity, the proposed heuristic can obtain effective solutions in very short and nearly zero time and is comparable with even metaheuristic algorithms and promising for practical problems.     

E.s.r. of Alberta tar sand bitumen and thermally hydrocracked products

A study of the vanadium and free radical species present in Athabasca bitumen and thermally upgraded products from a hydrocracking pilot plant was carried out. The samples were separated into asphaltene, chloroform resin, tetrahydrofuran resin and oil components, and the fractions studied by electron spin resonance. All samples except the oil fraction contained vanadyl (VO²⁺) ions and free radicals. It was found that even mild thermal treatment of bitumen produced considerable redistribution of vanadyl groups among the fractions, whereas at the severest hydrocracking conditions 94 wt% of all vanadyl groups were associated with the asphaltene fractions compared with only 58.5 wt% in the original bitumen. As the hydrocracking severity increased, the asphaltene vanadyl concentration initially increased above the value for unreacted bitumen and then decreased to a lower value. On the other hand, the resin vanadyl concentration decreased continuously and more rapidly than asphaltene vanadyl concentration. This indicates that vanadyl groups associated with the resin fractions are less stable than those associated with the asphaltenes and also suggests that transfer of vanadyl groups from the resin fractions to asphaltene predominates at low severity while removal of vanadyl groups predominates at high severity. The average spin Hamiltonian parameters showed that the chemical environment of vanadyl ions in the THF resins was significantly different from the vanadyl environment in the other two fractions.     

Effect of SDS,silver nanoparticles,and SDS + silver nanoparticles on methane hydrate semicompletion time

In this research, the semicompletion time (t_95%) of gas uptake in the process of methane hydrate formation in the presence and absence of sodium dodecyl sulfate (SDS) and silver nanoparticles (SNPs) is investigated. The experiments were carried out in a 460 cm³ stirred batch reactor at temperatures of 273.65 and 275.65 K and initial pressures of 5, 5.7, and 7 MPa. The results showed that the addition of both additives at all tested conditions, noticeably, decreases the semicompletion time of methane uptake, compared to pure water. The semicompletion time of methane uptake in the presence of 500 ppm SDS, 45 μM SNPs, and 500 ppm SDS + 45 μM SNPs is 75.6, 546.3, and 129.9 min, respectively, while that for pure water it is 8729.0 min at 273.65 K and 7 MPa.     

Collapse of the 16-Story Plasco Building in Tehran due to Fire

Fire Technology - On January 19, 2017 an accidental fire, which started by an electric shorting, resulted in the complete collapse of the 16-storey Plasco Building in Tehran. Twenty-two people...     

Analysis of flows driven by a torsionally–oscillatory lid in a fluid-saturated porous enclosure with thermal stable stratification

The convection flow caused by a torsionally–oscillatory lid with thermal stable stratification in an enclosure filled with porous medium is studied in this paper. The governing continuity, momentum and energy transport equations are solved by a semi-implicit projection finite element method. The Grashof number and Reynolds number for ranges 10⁴⩽Gr⩽10⁶, 10²⩽Re⩽10³ are involved in this research for Darcy number 10⁻², 10⁻⁴, 10⁻⁶ and porosity 0.4, 0.6. The results present that the permeability of porous medium deeply dominates the flow field and diminishes the flow strength as the permeability is decreased. The increase in the value of Gr/(Re²·Da) retards the stable stratification from the top surface to extend into the interior domain. The influence of oscillatory frequency is so serious in heat flux variation at some particular frequency corresponding to the resonant frequency. There is an evident resonant frequency at Da=10⁻² condition; however, this phenomenon is not clear for Da⩽10⁻⁴ at different oscillatory frequencies.     

MODAL IDENTIFICATION AND DAMAGE DETECTION USING THE DATA-DRIVEN STOCHASTIC SUBSPACE AND ARMAV METHODS

This paper presents results of modal identification and damage detection on the Steel-Quake structure using the autoregressive moving average vector and data-driven stochastic subspace methods. The methods directly work with the recorded time signals and allow to analyse linear systems where only the system output is measured, while the input is unknown but produced by uncorrelated random signals. These techniques can also be used directly to analyse data obtained from the free response of linear systems.