Influence of the transport processes on the dynamic characteristics of a continuous-flow chemical reactor

In this paper, we develop 3D dynamic models for polymer electrolyte fuel cells (PEFCs) and hydrogen tanks, respectively. The PEFC model considers the key components of a single PEFC and couples the various mechanisms that govern fuel cell transient including the electrochemical double-layer behavior, species transport, heat transfer, liquid water dynamics, and membrane water uptake. The hydrogen tank model includes a 3D description of the hydrogen discharging kinetics coupled with mass/heat transport in a LaNi5–based hydrogen tank. Efforts are made to discuss the dynamic characteristics of the PEFC and hydrogen tank together with the possible coupling of the two systems. Local electrochemical and hydride reaction rates, transport processes and associated limiting factors are investigated.

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A Qualitative Study of the Steady-State Solutions for a Continuous Flow Stirred Tank Chemical Reactor

SIAM Journal on Mathematical Analysis ◽

10.1137/0511030 ◽

1980 ◽

Vol 11 (2) ◽

pp. 316-339 ◽

Cited By ~ 72

Author(s):

M. Golubitsky ◽

B L. Keyfitz

Keyword(s):

Steady State ◽

Qualitative Study ◽

Continuous Flow ◽

Chemical Reactor ◽

Stirred Tank ◽

Steady State Solutions

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Certain Problems with the Application of Stochastic Diffusion Processes for the Description of Chemical Engineering Phenomena. Stochastic Model of Isothermal Continuous Flow Chemical Reactor

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941772 ◽

1994 ◽

Vol 59 (8) ◽

pp. 1772-1787

Author(s):

Vladimír Kudrna ◽

Libor Vejmola ◽

Pavel Hasal

Keyword(s):

Continuous Flow ◽

Chemical Engineering ◽

Diffusion Processes ◽

Chemical Reactor ◽

Point Of View ◽

General Point ◽

Stochastic Description ◽

One Dimensional ◽

Reactor Operating ◽

Parameter Values

A model of an isothermal one-dimensional continuous flow chemical reactor operating at the steady state was derived using a stochastic description of motion of the reacting molecules. The model enables evaluation of the conversion of the reacting components. At the limiting parameter values the model yields results identical to those of the simplified models conventionally used in chemical reactor engineering. The model also enables the applicability of Danckwerts' boundary conditions to be assessed from a more general point of view.

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Evaluation of four different coagulants used for chemical dephosphorization of membrane bioreactor effluent

E3S Web of Conferences ◽

10.1051/e3sconf/202016701009 ◽

2020 ◽

Vol 167 ◽

pp. 01009

Author(s):

Qin Cai ◽

Hui-qiang Li ◽

Ping Yang

Keyword(s):

Removal Efficiency ◽

Phosphorus Removal ◽

Continuous Flow ◽

Membrane Bioreactor ◽

Removal Rate ◽

Sewage Treatment ◽

Chemical Reactor ◽

Domestic Sewage ◽

Internal Loop ◽

Polyaluminium Chloride

A continuous flow chemical reactor was constructed to study the dephosphorization effect on the effluent of the oxygen-limited internal-loop fluidized membrane bioreactor (IF-MBR) for domestic sewage treatment. Removal effect of total phosphorus (TP) by four coagulants of AlCl3, FeCl3, polyaluminum ferric chloride (PAFC) and polyaluminium chloride (PAC) was evaluated. Results showed that when the ratio of coagulants to TP was 5 (coagulants in terms of Fe and Al), the removal efficiency of TP by FeCl3 was 92.5% and the addition of FeCl3 resulted in an increase in the chromaticity of the effluent. PAC and PAFC had good removal of TP, and the removal percentage achieved 96.2 and 97.4, respectively. However, the flocs they produced were small and light, and the performance in settlement was poor. AlCl3 performed well as a phosphorus removal agent, the removal rate of TP reached 97.4%, and the flocs were large and dense. Based on this, AlCl3 was the best choice for IF-MBR and then the experiment further optimized the Al/P ratio. Results showed that when the Al/P ratio was above 1:1, the effluent TP concentration was lower than 1mg/L; when the ratio was higher than 2.5:1, the effluent TP was lower than 0.5mg/L.

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