The Experts below are selected from a list of 405396 Experts worldwide ranked by ideXlab platform
Petro Kapustenko - One of the best experts on this subject based on the ideXlab platform.
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accounting for the thermal resistance of Cooling Water fouling in plate heat exchangers
Applied Thermal Engineering, 2013Co-Authors: Olga P. Arsenyeva, B D Crittenden, Mangyan Yang, Petro KapustenkoAbstract:Of the many different approaches available to mitigate fouling, the use of enhanced heat transfer surfaces is a principal method. The flow in channels of plate heat exchangers (PHEs) has high levels of turbulence due to the channels intricate geometry. In principle therefore, this type of heat transfer augmentation should lead to fouling mitigation. The effects of process parameters on fouling in PHE channels are studied in this article. The asymptotic behaviour of Water fouling is examined specifically and the net rate of fouling accumulation is described as the difference between the fouling deposition rate and the fouling removal rate. An equation is proposed to account for how the fouling resistance varies with time. The conclusion is that for scaling there exist threshold conditions on wall shear stress, wall temperature and salt content, beyond which fouling deposition starts. The fouling deposition rate expression proposed for tubes incorporating heat transfer enhancement as used by Yang and Crittenden is adapted to be used in a new model for PHEs. Comparison with experimental data published in the literature reveals good agreement with the proposed model. The model can then be used to predict Cooling Water fouling development over time for all the heat exchangers in a chosen industrial circuit.
Ebn M Touhami - One of the best experts on this subject based on the ideXlab platform.
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inhibitive properties of 2 5 bis n methylphenyl 1 3 4 oxadiazole and biocide on corrosion biocorrosion and scaling controls of brass in simulated Cooling Water
Corrosion Science, 2014Co-Authors: A Rochdi, R Touir, El M Bakri, Ebn M Touhami, N Dkhireche, M Sfaira, O Kassou, B Mernari, B HammoutiAbstract:Abstract 2,5-Bis( n -methylphenyl)-1,3,4-oxadiazole with ( n = 2,3,4), denoted n -MPOX, have been investigated by using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) methods, to evaluate the electrochemical behavior of brass in simulated Cooling Water system. The PP study revealed that oxadiazole inhibited both cathodic and anodic reactions, indicating a mixed type control of inhibition. It was shown that, 3-MPOX as well as 4-MPOX, were the best inhibitors and the inhibition efficiency followed the sequence: 3-MPOX ⩾ 4-MPOX ≫ 2-MPOX. The interference between non-oxidizing biocide CTAB and 3-MPOX and 4-MPOX against corrosion and biocorrosion has also been studied.
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corrosion and scale inhibition of low carbon steel in Cooling Water system by 2 propargyl 5 o hydroxyphenyltetrazole
Journal of Industrial and Engineering Chemistry, 2013Co-Authors: N Dkhireche, R Touir, El M Bakri, Ebn M Touhami, A Dahami, A Rochdi, J Hmimou, El A Hallaoui, Alami Anouar, H TakenoutiAbstract:Abstract The 2-propargyl-5-o-hydroxyphenyltetrazole (PHPT) has been tested as corrosion inhibitor for low carbon steel in simulated Cooling Water. The polarization curves showed that PHPT acts as mixed-type inhibitor. Its inhibition efficiency was found to enhance with increase of the inhibitor concentration and immersion time due to the formation of the inhibitor film on the metal surface as indicated by electrochemical impedance spectroscopy measurements. To complete the formulation further, a non oxidizing biocide was added. Its presence with PHPT does not affect its inhibitory performance and it can be served as a basic component of the formulation for Cooling Water system.
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corrosion and scale processes and their inhibition in simulated Cooling Water systems by monosaccharides derivatives part i eis study
Desalination, 2009Co-Authors: R Touir, Ebn M Touhami, N Dkhireche, M Lakhrissi, B Lakhrissi, M SfairaAbstract:Abstract A study of the ordinary mild steel/Cooling Water interface, with and without inhibitor, was carried out using electrochemical impedance spectroscopy (EIS). EIS spectra in uninhibited medium reveal that a layer of corrosion and scale products is formed naturally and evolves with the immersion time. Monosaccharides derivatives were used as corrosion inhibitors. Most of them exhibit good behaviour against corrosion of ordinary steel in simulated Water systems. Their inhibiting efficiency increases with concentration rise and depends on molecular structure especially –OH groups' position on two adjacent carbons and their number. In addition, the effect of MoO42− on the corrosion inhibition in the presence of the best inhibitor was also studied by EIS. The addition of MoO42− enhanced the inhibition efficiency.
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sodium gluconate as corrosion and scale inhibitor of ordinary steel in simulated Cooling Water
Corrosion Science, 2008Co-Authors: R Touir, M Cenoui, El M Bakri, Ebn M TouhamiAbstract:Abstract The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated Cooling Water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10 −4 M to 10 −1 M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated Cooling Water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhibitor.
R Touir - One of the best experts on this subject based on the ideXlab platform.
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inhibitive properties of 2 5 bis n methylphenyl 1 3 4 oxadiazole and biocide on corrosion biocorrosion and scaling controls of brass in simulated Cooling Water
Corrosion Science, 2014Co-Authors: A Rochdi, R Touir, El M Bakri, Ebn M Touhami, N Dkhireche, M Sfaira, O Kassou, B Mernari, B HammoutiAbstract:Abstract 2,5-Bis( n -methylphenyl)-1,3,4-oxadiazole with ( n = 2,3,4), denoted n -MPOX, have been investigated by using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) methods, to evaluate the electrochemical behavior of brass in simulated Cooling Water system. The PP study revealed that oxadiazole inhibited both cathodic and anodic reactions, indicating a mixed type control of inhibition. It was shown that, 3-MPOX as well as 4-MPOX, were the best inhibitors and the inhibition efficiency followed the sequence: 3-MPOX ⩾ 4-MPOX ≫ 2-MPOX. The interference between non-oxidizing biocide CTAB and 3-MPOX and 4-MPOX against corrosion and biocorrosion has also been studied.
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corrosion and scale inhibition of low carbon steel in Cooling Water system by 2 propargyl 5 o hydroxyphenyltetrazole
Journal of Industrial and Engineering Chemistry, 2013Co-Authors: N Dkhireche, R Touir, El M Bakri, Ebn M Touhami, A Dahami, A Rochdi, J Hmimou, El A Hallaoui, Alami Anouar, H TakenoutiAbstract:Abstract The 2-propargyl-5-o-hydroxyphenyltetrazole (PHPT) has been tested as corrosion inhibitor for low carbon steel in simulated Cooling Water. The polarization curves showed that PHPT acts as mixed-type inhibitor. Its inhibition efficiency was found to enhance with increase of the inhibitor concentration and immersion time due to the formation of the inhibitor film on the metal surface as indicated by electrochemical impedance spectroscopy measurements. To complete the formulation further, a non oxidizing biocide was added. Its presence with PHPT does not affect its inhibitory performance and it can be served as a basic component of the formulation for Cooling Water system.
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corrosion and scale processes and their inhibition in simulated Cooling Water systems by monosaccharides derivatives part i eis study
Desalination, 2009Co-Authors: R Touir, Ebn M Touhami, N Dkhireche, M Lakhrissi, B Lakhrissi, M SfairaAbstract:Abstract A study of the ordinary mild steel/Cooling Water interface, with and without inhibitor, was carried out using electrochemical impedance spectroscopy (EIS). EIS spectra in uninhibited medium reveal that a layer of corrosion and scale products is formed naturally and evolves with the immersion time. Monosaccharides derivatives were used as corrosion inhibitors. Most of them exhibit good behaviour against corrosion of ordinary steel in simulated Water systems. Their inhibiting efficiency increases with concentration rise and depends on molecular structure especially –OH groups' position on two adjacent carbons and their number. In addition, the effect of MoO42− on the corrosion inhibition in the presence of the best inhibitor was also studied by EIS. The addition of MoO42− enhanced the inhibition efficiency.
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sodium gluconate as corrosion and scale inhibitor of ordinary steel in simulated Cooling Water
Corrosion Science, 2008Co-Authors: R Touir, M Cenoui, El M Bakri, Ebn M TouhamiAbstract:Abstract The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated Cooling Water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10 −4 M to 10 −1 M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated Cooling Water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhibitor.
Tianwei Yang - One of the best experts on this subject based on the ideXlab platform.
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experimental study on flue gas condensate capture and heat transfer in staggered tube bundle heat exchangers
Applied Thermal Engineering, 2018Co-Authors: Enlu Wang, Kai Li, Naveed Husnain, Deli Li, Wei Wu, Tianwei YangAbstract:Abstract Experiments on the flue gas condensation in multi-row staggered tube bundle heat exchangers are carried out. The effects of the flue gas velocity, Water vapor volume fraction, Cooling Water flow rate, Cooling Water temperature, and Cooling Water flow arrangement (series or parallel) on the condensate capture rate and heat transfer coefficient are presented and discussed. The compound heat transfer coefficient can attain a value 2–4 times that of the pure convective heat transfer coefficient, and the condensate capture rate can attain a value above 50%. There is a suitable Cooling Water flow rate with an adequately low wall temperature and an adequately high heat transfer coefficient and condensate capture rate. However, the condensate capture rates of the heat exchangers in the series arrangement are apparently lower than those in the parallel arrangement. With the increase of the Cooling Water temperature, the condensate capture rate decreases; however, the heat transfer coefficient increases under a similar condition. Finally, the empirical formula of the heat transfer coefficient of multi-row staggered tube bundle heat exchangers is determined, and it exhibits good agreement with the experimental data.
Olga P. Arsenyeva - One of the best experts on this subject based on the ideXlab platform.
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accounting for the thermal resistance of Cooling Water fouling in plate heat exchangers
Applied Thermal Engineering, 2013Co-Authors: Olga P. Arsenyeva, B D Crittenden, Mangyan Yang, Petro KapustenkoAbstract:Of the many different approaches available to mitigate fouling, the use of enhanced heat transfer surfaces is a principal method. The flow in channels of plate heat exchangers (PHEs) has high levels of turbulence due to the channels intricate geometry. In principle therefore, this type of heat transfer augmentation should lead to fouling mitigation. The effects of process parameters on fouling in PHE channels are studied in this article. The asymptotic behaviour of Water fouling is examined specifically and the net rate of fouling accumulation is described as the difference between the fouling deposition rate and the fouling removal rate. An equation is proposed to account for how the fouling resistance varies with time. The conclusion is that for scaling there exist threshold conditions on wall shear stress, wall temperature and salt content, beyond which fouling deposition starts. The fouling deposition rate expression proposed for tubes incorporating heat transfer enhancement as used by Yang and Crittenden is adapted to be used in a new model for PHEs. Comparison with experimental data published in the literature reveals good agreement with the proposed model. The model can then be used to predict Cooling Water fouling development over time for all the heat exchangers in a chosen industrial circuit.
