Large amounts of energy are consumed during the manufacturing of cement especially during the calcination process which also emits large amounts of CO2. A large part of the energy used in the making of cement is relea...
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Large amounts of energy are consumed during the manufacturing of cement especially during the calcination process which also emits large amounts of CO2. A large part of the energy used in the making of cement is released as waste heat. A process to capture CO2 by integrating the recovery and utilization of waste heat has been designed. Aspen Plus software was used to calculate the amount of waste heat and the efficiency of energy utilization. The data used in this study was based on a dry process cement plant with a 5-stage preheater and a precalciner with a cement output of 1 Mt/y. According to the calculations: 1) the generating capacity of the waste heat recovery system is 4.9MW. 2) The overall CO2 removal rate was as high as 78.5%. 3) The efficiency of energy utilization increased after the cement producing process was retrofitted with this integrated design.
In this paper,a simple method to plate a hydrophobic coating on the inner surface of a small-scaled tube was proposed,where the coating consisted of carbon *** common plastics polystyrene,polycarbonate and polyethylen...
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In this paper,a simple method to plate a hydrophobic coating on the inner surface of a small-scaled tube was proposed,where the coating consisted of carbon *** common plastics polystyrene,polycarbonate and polyethylene were used as the feedstocks to be processed in supercritical water in a quartz tubular *** reaction,the contact angle of droplet on the inner surface of the quartz tube was turned out to be over 100°,significantly larger than that of the blank tube 54°.When processing polystyrene in the 750℃ supercritical water for 10 min,the largest contact angle was obtained,up to 145°.Besides,in this sample,the size of carbon spheres was smallest,about 2.09μm diameter on *** comparing among different types of plastics under the same condition,the contact angle of surface made from PC took the dominant position over that of PS and PE,124°,100°and 90°,*** the sample made from PC,carbon spheres adhered into a mountainlike shape,producing a binary geometric ***,this research could be helpful in the discussion of plastic waste management and carbon spheres fabrication with low cost.
Blending hydrogen into natural gas pipelines enables the large-scale delivery and application of hydrogen, contributing to carbon emission reduction and promoting the transition to cleaner energy sources. Accurate and...
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Various Mn-based catalysts for NO oxidation were prepared using MnO_(x)as active compound,while Ti O_(2)and Al_(2)O_(3)were adopted as catalyst *** performance of the catalysts was tested to study the effect of suppor...
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Various Mn-based catalysts for NO oxidation were prepared using MnO_(x)as active compound,while Ti O_(2)and Al_(2)O_(3)were adopted as catalyst *** performance of the catalysts was tested to study the effect of support on Mn-based catalyst *** of the catalysts followed as Mn_(0.4)/Al>Mn_(0.2)/Al>Mn_(0.4)/Ti>Mn_(0.2)/Ti>MnO_(x)>Al_(2)O_(3)on the whole,indicating the synergism of MnO_(x)and Al_(2)O_(3)for NO catalytic *** were analyzed according to characterization *** oxygen on catalyst rather than lattice oxygen was detected as the active oxidizer for NO *** catalyst support,Al_(2)O_(3)provided more sites to carry surface adsorbed oxygen than TiO_(2),resulting in the presence of more active oxygen on Mn O_(x)/Al_(2)O_(3)than on MnO_(x)/TiO_(2).Moreover,MnO_(x)/Al_(2)O_(3)possessed high surface area and pore volume,which greatly benefited the adsorption of NO on catalyst and further favored the oxidation of NO by active *** these advantages helped Mn_(0.4)/Al exhibited the best catalytic efficiency.
The key reasons that the present method cannot be used to solve the industrial multi- phase flow pattern recognition are clarified firstly. The prerequisite to realize the online recognition is proposed and recognitio...
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The key reasons that the present method cannot be used to solve the industrial multi- phase flow pattern recognition are clarified firstly. The prerequisite to realize the online recognition is proposed and recognition rules for partial flow pattern are obtained based on the massive experimental data. The standard templates for every flow regime feature are calculated with self-organization cluster algorithm. The multi-sensor data fusion method is proposed to realize the online recognition of multiphaseflow regime with the pressure and differential pressure signals, which overcomes the severe influence of fluid flow velocity and the oil fraction on the recognition. The online recognition method is tested in the practice, which has less than 10 percent measurement error. The method takes advantages of high confidence, good fault tolerance and less requirement of single sensor performance.
This paper studies the projectile electron loss cross sections of C^3+ colliding with atomic hydrogen in the frame work of extended over-barrier model at intermediate velocities (25 keV/u-600 keV/u). The electron l...
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This paper studies the projectile electron loss cross sections of C^3+ colliding with atomic hydrogen in the frame work of extended over-barrier model at intermediate velocities (25 keV/u-600 keV/u). The electron loss is calculated in terms of the interaction between the screened target nucleus and the active projectile electron and of the interaction between projectile electron and target electron. Compared with the convergent close-coupling calculations, screening and anti-screening calculations, this model satisfactorily reproduces the experimentally obtained energy dependence of the electron-impact ionisation cross sections and the single electron loss cross sections over the energy range investigated here.
By using an ensemble-averaged two-fluid model,with valid closure conditions of interfacial momentum exchange due to virtual mass force,viscous shear stress and drag force,a model for pressure wave propagation in a hor...
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By using an ensemble-averaged two-fluid model,with valid closure conditions of interfacial momentum exchange due to virtual mass force,viscous shear stress and drag force,a model for pressure wave propagation in a horizontal gas-liquid bubbly flow is *** to the small perturbation theory and solvable condition of one-order linear uniform equations,a dispersion equation of pressure wave is *** pressure wave speed calculated from the model is compared and in good agreement with existing *** to the dispersion equation,the propagation and attenuation of pressure wave are investigated *** factors affecting pressure wave,such as void fraction,pressure,wall shear stress,perturbation frequency,virtual mass force and drag force,are *** result shows that the decrease in system pressure,the increase in void fraction and the existence of wall shear stress,will cause a decrease in pressure wave speed and an increase in the attenuation coefficient in the horizontal gas-liquid bubbly *** effects of perturbation frequency,virtual mass and drag force on pressure wave in the horizontal gas-liquid bubbly flow at low perturbation frequency are different from that at high perturbation frequency.
A low mass flux steam jet in subcooled water was experimentally *** transition of flow pattern from stable jet to condensation oscillation was observed at relatively high water *** axial total pressures,the axial and ...
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A low mass flux steam jet in subcooled water was experimentally *** transition of flow pattern from stable jet to condensation oscillation was observed at relatively high water *** axial total pressures,the axial and radial temperature distributions were measured in the jet *** results indicated that the pressure and temperature distributions were mainly influenced by the water *** correlations corrected with water temperature were given to predict the dimen-sionless axial pressure peak distance and axial temperature distributions in the jet region,the results showed a good agreement between the predictions and ***,the self-similarity property of the radial temperature was obtained,which agreed well with Gauss *** present work,all the dimensionless properties were mainly dependent on the water temperature but weakly on the nozzle size under a certain steam mass flux.
Because of the practical importance of two-phase instabilities, substantial efforts have been made to date to understand the physical phenomena governing such instabilities and to develop computational tools to model ...
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Because of the practical importance of two-phase instabilities, substantial efforts have been made to date to understand the physical phenomena governing such instabilities and to develop computational tools to model the dynamics. The purpose of this study is to present a numerical model for the analysis of flow-induced instabilities in forced-convection steam generator. The model is based on the assumption of homogeneous two-phase flow and ther- modynamic equilibrium of the phases. The thermal capacity of the heater wall has been included in the analysis. The model is used to analyze the flow instabilities in the steam generator and to study the effects of system pressure, mass flux, inlet temperature and inlet/outlet restriction, gap size, the ratio of do / di, and the ratio of qi / qo on the system be- havior.
Prediction of critical heat flux (CHF) in annular flow is important for the safety of once - through steam generator and the reactor core under accident conditions. The dryout in annular flow occurs at the point where...
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Prediction of critical heat flux (CHF) in annular flow is important for the safety of once - through steam generator and the reactor core under accident conditions. The dryout in annular flow occurs at the point where the film is depleted due to entrainment, deposition, and evaporation. The film thickness, film mass flow rate along axial distribution, and CHF are calculated in vertical upward round tube on the basis of a separated flow model of annular flow. The theoretical CHF values are higher than those derived from experimental data, with error being within 30%.
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