scholarly journals Kinetic Study of Low Temperature Sulfur Dioxide Removal Reaction By Sodium Carbonate Using Random Pore Model

2021 ◽  
Author(s):  
Iman Omidi ◽  
Habib Ale Ebrahim
Keyword(s):  
Low Temperature ◽  
Kinetic Study ◽  
Sodium Carbonate ◽  
Power Plants ◽  
Product Layer ◽  
Order Kinetic ◽  
Time Data ◽  
Pore Model ◽  
Model Predictions ◽  
Random Pore Model

Abstract An experimental investigation of low temperature SO2 removal by porous sodium carbonate was carried out by thermogravimetry. As well as, applied mathematical modeling based on the random pore model was employed to kinetic study of this reaction. The experiments were performed at various temperatures (100-250 oC) and different SO2 concentrations (0.13-1.12 vol%). The initial slopes procedure was used to determine dependency of the reaction rate constants versus temperature. First-order kinetic with respect to gaseous reactant was found and value of activation energy was attained as 22.5 kJ mol-1. Product layer diffusion coefficients were evaluated by the best fitting of experimental data with the model predictions. These random pore model predictions indicated good agreement with experimental conversion-time data at various conditions. The resulted kinetic parameters were avail abled for engineering calculations of SO2 abatement from the coal-based power plants by low-temperature flue gas desulfurization.

scholarly journals Kinetic study of CO2 reaction with CaO by a modified random pore model

2016 ◽  
Vol 18 (1) ◽  
pp. 93-98 ◽  
Author(s):  
S.M.M. Nouri ◽  
H. Ale Ebrahim
Keyword(s):  
Mercury Porosimetry ◽  
Nitrogen Adsorption ◽  
Intrinsic Rate ◽  
Product Layer ◽  
Carbonation Reaction ◽  
Pore Model ◽  
Partial Pressures ◽  
Pore Size Distributions ◽  
Kinetics Of ◽  
Random Pore Model

Abstract In this work, a modified random pore model was developed to study the kinetics of the carbonation reaction of CaO. Pore size distributions of the CaO pellets were measured by nitrogen adsorption and mercury porosimetry methods. The experiments were carried out in a thermogravimeter at different isothermal temperatures and CO2 partial pressures. A fractional concentration dependency function showed the best accuracy for predicting the intrinsic rate of reaction. The activation energy was determined as 11 kcal/mole between 550–700°C. The effect of product layer formation was also taken into account by using the variable product layer diffusivity. Also, the model was successfully predicted the natural lime carbonation reaction data extracted from the literature.

A Comprehensive Kinetic Study of the Reaction of SO2with CaO by the Random Pore Model

2014 ◽  
Vol 37 (12) ◽  
pp. 2037-2046 ◽  
Author(s):  
Hadi Moshiri ◽  
Bahram Nasernejad ◽  
Habib Ale Ebrahim ◽  
Mahboobeh Taheri
Keyword(s):  
Kinetic Study ◽  
Pore Model ◽  
Random Pore Model

scholarly journals A modified random pore model for carbonation reaction of calcium oxide with carbon dioxide

2015 ◽  
Vol 69 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Seyed Nouri ◽  
Habib Ebrahim ◽  
Bahram Nejad
Keyword(s):  
Carbon Dioxide ◽  
Calcium Oxide ◽  
Product Layer ◽  
Carbonation Reaction ◽  
Pore Model ◽  
Time Profiles ◽  
Rate Functions ◽  
Conversion Time ◽  
Reaction Constants ◽  
Random Pore Model

In this work, the random pore model was modified for a general concentration dependency and also bulk flow effect, in order to predict the carbonation reaction of calcium oxide with carbon dioxide. This reaction is one of the main methods for carbon dioxide capture from industrial flue gases. Different kinetic rate concentration functions were tested with the various literature experimental data for finding the best reaction constants and rate functions. Moreover, an exponential function for the diffusion of carbon dioxide through the product layer was proposed from the whole experimental conversion-time profiles.

A Comprehensive Kinetic Study of the SO2 Removal Reaction by Pure CuO with the Random Pore Model

2016 ◽  
Vol 41 (4) ◽  
pp. 385-397 ◽  
Author(s):  
Reza Bahrami ◽  
Habib Ale Ebrahim ◽  
Rouein Halladj ◽  
Ali Afshar
Keyword(s):  
Experimental Investigation ◽  
Mathematical Modelling ◽  
Product Layer ◽  
Solid Reaction ◽  
Pore Model ◽  
Time Profiles ◽  
So2 Removal ◽  
Partial Pressures ◽  
Conversion Time ◽  
Random Pore Model

An experimental investigation of the SO2 removal reaction by pure CuO was performed by thermogravimetry. In addition, mathematical modelling of this non-catalytic gas-solid reaction was performed using the random pore model. Modelling predictions of CuO conversion-time profiles at various temperatures and SO2 partial pressures compared well with the experimental results. The inherent rate constants and the product layer diffusivities were estimated between 400 and 600 °C.

Improving the efficiency and reliability of electric power generation at incineration plants

2020 ◽  
Vol 12 (4) ◽  
pp. 281-285
Author(s):  
A. V. Martynov ◽  
N. E. Kutko
Keyword(s):  
Low Temperature ◽  
Power Plants ◽  
Thermal Power ◽  
Moscow Region ◽  
Capital Costs ◽  
Working Medium ◽  
The Creation ◽  
Working Media ◽  
Near Future ◽  
Efficiency And Reliability

The article deals with the problem of waste disposal and, accordingly, landfills in the Moscow Region, which have now become the number 1 problem for the environment in Moscow and the Moscow Region. To solve this problem, incineration plants (IP) will be established in the near future. 4 plants will be located in the Moscow Region that will be able to eliminate 2800 thousand tons of waste per year. Burning of waste results in formation of slag making 25% of its volume, which has a very high temperature (1300.1500°C). An arrangement is considered, in which slag is sent to a water bath and heats the water to 50.90°C. This temperature is sufficient to evaporate any low-temperature substance (freons, limiting hydrocarbons, etc.), whereupon the steam of the low-temperature working medium is sent to a turbine, which produces additional electricity. The creation of a low-temperature thermal power plant (TPP) increases the reliability of electricity generation at the IP. The operation of low-temperature TPPs due to the heat of slag is very efficient, their efficiency factor being as high as 40.60%. In addition to the efficiency of TPPs, capital costs for the creation of additional devices at the IP are of great importance. Thermal power plants operating on slag are just such additional devices, so it is necessary to minimize the capital costs of their creation. In addition to equipment for the operation of TPPs, it is necessary to have a working medium in an amount determined by calculations. From the wide variety of working media, which are considered in the article, it is necessary to choose the substance with the lowest cost.

Leaching Kinetics of Atrazine and Inorganic Chemicals in Tilled and Orchard Soils

2014 ◽  
Vol 28 (2) ◽  
pp. 231-237 ◽  
Author(s):  
Lech W. Szajdak ◽  
Jerzy Lipiec ◽  
Anna Siczek ◽  
Artur Nosalewicz ◽  
Urszula Majewska
Keyword(s):  
Reaction Rate ◽  
Inorganic Compounds ◽  
Model Performance ◽  
Order Reaction ◽  
First Order Reaction ◽  
Order Kinetic ◽  
Time Data ◽  
First Order ◽  
Concentration Changes ◽  
Reaction Constants

Abstract The aim of this study was to verify first-order kinetic reaction rate model performance in predicting of leaching of atrazine and inorganic compounds (K+1, Fe+3, Mg+2, Mn+2, NH4 +, NO3 - and PO4 -3) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals were from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil correspond with both higher total porosity and contribution of biological pores in the former. The first order reaction constants for the leaching of chemical compounds enables prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.

scholarly journals Highly Efficient Adsorption of Aqueous Pb(II) with Mesoporous Metal-Organic Framework-5: An Equilibrium and Kinetic Study

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
José María Rivera ◽  
Susana Rincón ◽  
Cherif Ben Youssef ◽  
Alejandro Zepeda
Keyword(s):  
Kinetic Study ◽  
Photoelectron Spectroscopy ◽  
Metal Organic Framework ◽  
Isotherm Models ◽  
Ionic Exchange ◽  
Order Kinetic ◽  
X Ray ◽  
Metal Organic ◽  
Mesoporous Metal ◽  
Organic Framework

Mesoporous metal-organic framework-5 (MOF-5), with the composition Zn4O(BDC)3, showed a high capacity for the adsorptive removal of Pb(II) from 100% aqueous media. After the adsorption process, changes in both morphology and composition were detected using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) system, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analysis. The experimental evidence showed that Zn(II) liberation from MOF-5 structure was provoked by the water effect demonstrating that Pb(II) removal is not due to ionic exchange with Zn. A kinetic study showed that Pb(II) removal was carried out in 30 min with a behavior of pseudo-second-order kinetic model. The experimental data on Pb(II) adsorption were adequately fit by both the Langmuir and BET isotherm models with maximum adsorption capacities of 658.5 and 412.7 mg/g, respectively, at pH 5 and 45°C. The results of this work demonstrate that the use of MOF-5 has great potential for applications in environmental protection, especially regarding the removal of the lead present in industrial wastewaters and tap waters.

Three-Pore Model Predictions of 24-Hour Automated Peritoneal Dialysis Therapy Using Bimodal Solutions

2011 ◽  
Vol 31 (5) ◽  
pp. 537-544 ◽  
Author(s):  
Alp Akonur ◽  
J. Ken Leypoldt
Keyword(s):  
Peritoneal Dialysis ◽  
Glucose Absorption ◽  
Patient Transport ◽  
Pore Model ◽  
Low Concentrations ◽  
Baxter Healthcare ◽  
All Solutions ◽  
Model Predictions ◽  
Fast Transport ◽  
Transport Type

BackgroundRecently, bimodal peritoneal dialysis (PD) solutions containing low concentrations of Na have been shown to increase 24-hour ultrafiltration (UF) or UF efficiency (UF volume per gram of carbohydrate or CHO absorbed) and Na removal in high (“fast”) transport patients during automated PD therapy. We used computer simulations to compare UF efficiency and Na removal at equivalent 24-hour UF volumes using either a generic bimodal solution (2.27% glucose + 7.5% icodextrin) during the long dwell or an increase in the glucose concentration during the short dwells, with all solutions containing Na at the conventional concentration (132 mEq/L).MethodsThe 3-pore model has been shown to accurately predict peritoneal transport for PD solutions containing glucose or icodextrin, or both. Here, we used that model to calculate 24-hour UF volume, CHO absorption, and Na removal for high (H), high-average (HA), and low-average (LA) transport patients on automated PD. Nighttime therapy consisted of 1.36% or 2.27% glucose solution (or both), and daytime therapy consisted of either Extraneal (Baxter Healthcare Corporation, Deerfield, IL, USA) or a bimodal solution.ResultsAs expected, addition of glucose to either the long dwell or the short dwells resulted in increased UF volume and glucose absorption. The increase in UF was a function of patient transport type (bimodal range: 288 – 490 mL; short-dwell range: 323 – 350 mL), and the increase in CHO absorption was smaller with glucose added to short dwells than with bimodal solution (range: 18 – 30 g vs. 34 – 39 g). The 24-hour UF efficiency was higher when high glucose concentrations were used during short-dwell exchanges than when a bimodal PD solution was used for the long dwell (0.6 to 1.2 mL/g vs. –0.1 to 0.5 mL/g). By contrast, Na removal was lower with the short-dwell exchanges (28.3 – 30.7 mmol vs. 36.2 – 53.3 mmol), likely because of more pronounced Na sieving.ConclusionsOur modeling studies predict that generic bimodal PD solutions will provide higher Na removal but not higher 24-hour UF efficiency compared with current automated PD prescriptions using Extraneal for the long dwell and glucose-containing solutions for the short dwells. The modeling predictions from this study require clinical validation.

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