Temperature Profile of Reactor

Figure 2. Temperature profile of reactor with methanol feed (lower curve prior to feeding)...

Dias JAC, Assaf JM (2008) Autothermal reforming of methane over Ni/7-Al203 promoted with Pd. The effect of the Pd source in activity, temperature profile of reactor and in ignition. Appl Catal A 334 243-250... 

Our HP HCR model includes three major parts of the commercial HCR process reactors, fractionators, and hydrogen recycle system. In the reactor model, we define the inlet temperature of each catalyst bed, and the model will calculate the outlet temperature of each bed. The AADs of catalyst bed outlet temperatures of the two HCR reactors are 1.8 °C and 3.2 °C for series 1 and series 2, respectively. Figures 6.49 to 6.50 show the model predictions of WARTs of HT reactors and HCR reactors. The model generates good predictions on the temperature profile of reactors. Figure 6.51 represents the modeling result of the makeup hydrogen flow rate, and the ARD is only 2%. 

The integrated HCR process models are able to predict accurately the product yields, distillation curves of liquid products, and temperature profiles of reactors and fractionators. 

Figure 11.6 Model (solid) versus experiments (points) for the temperature profile of an integrated SMR reactor.

Fig.3. Temperature profiles of the honeycomb reactor. Insulator wall (—and aluminum wall (-).

This problem indicates the considerations that enter into the design of a tubular reactor for an endothermic reaction. The necessity of supplying thermal energy to the reactor contents at an elevated temperature implies that the heat transfer considerations will be particularly important in determining the longitudinal temperature profile of the reacting fluid. This problem is based on an article by Fair and Rase (1). 

Figure 26 shows the predicted axial gas temperature profiles during reactor start-up for standard type I conditions with varying numbers of axial collocation points. Eight or more axial collocation points provide similar results, and even simulations with six collocation points show minimal inaccuracy. However, reducing the number of collocation points below this leads to major discrepancies in the axial profiles. 

The heat transfer coefficient is 142 kJ s-1 K-1 m-2, and the resulting temperature profiles of the process and the coolant are given in Figure 6.70. The two temperatures are pinched together very severely at the end of the reactor, where the process leaves and... 

A mathematical model was developed, able to predict monomer conversion and temperature profiles of industrial tubular reactors for the production of low-density polyethylene, in different operating conditions. 

In the literature many studies on LDPE tubular reactors are found (2-6).All these studies present models of the tubular reactor, able to predict the influence, on monomer conversion and temperature profiles, of selected variables such as initiator concentration and jacket temperature. With the exception of the models of Mullikin, that is an analog computer model of an idealized plug-flow reactor, and of Schoenemann and Thies, for which insufficient details are given, all the other models developed so far appear to have some limitations either in the basic hypotheses or in the fields of application. 

Figure 10. Temperature profiles of naphtha reactor. (O 0) Data, (-----)...

Figure 10 Axial (left) and radial (right) temperature profiles of the packed-commercial>pellet bed during steam reforming of methane and nitrogen flow conditions at gaseous-inlet hourly space velocities of 8400 hr" [X/R = distance from centerline/inside radius of reactor]. (From Ref. 10.)...

Figure 3.4. Typical temperature profile of a CPO reactor with concentration profiles of fuel and 02 along a CPO catalyst bed.

In this paper we will discuss the application of a general batch reactor model that considers the reaction kinetics, heats of reaction, heat transfer properties of the reactor, physical properties of the reactants and the products, to predict 1) The concentration profile of the products, thus enabling process optimization 2) Temperature profile during the reaction, which provides a way to avoid conditions that lead to a thermal runaway 3) Temperature profile of the jacket fluid while maintaining a preset reactor temperature 4) Total pressure in the reactor, gas flow rates and partial pressure of different components. The model would also allow continuous addition of materials of different composition at different rates of addition. 

A kinetic model was developed from the results of catalyst screening studies that relates reaction rates to temperature, space velocity, and steam to gas ratio. A finding of kinetic modeling studies is that conversion of carbon monoxide could be enhanced in a thermal gradient compared to reactions conducted isothermally. By managing the temperature profile of a reactor, reactants can be fed at a high temperature where rapid kinetics promotes an initial approach to equilibrium. As the reaction mixture is cooled, conversion is increased due to more favorable thermodynamic driving forces. 

To optimize the performance of a microchannel-based water gas shift reactor, the temperature profile of the reactor was adjusted as a means to provide the best trade-off of rapid kinetics at high temperature and favorable thermodynamics at low temperature. 

After a suitable period of onstream operation, feed to an Individual reactor is discontinued and the reactor is reheated/regenerated. Re-heat/regeneration air heated in the regeneration air heater (6) is passed through the reactors. The regeneration air serves to restore the temperature profile of the bed to its initial onstream condition in addition to burning coke off the catalyst. When reheat/regeneration is completed, the reactor is re-evacuated for the next onstream period. 

An even closer coupling of the reactor-heat exchange combination is obtained by the countercurrent operation illustrated in Figure 6.14. This problem was first studied by Grens and McKean [E.A. Grens and R.A. McKean, Chem. Eng. Sci., 18, 291 (1963)] who obtained an analytical solution for the temperature profiles of both reactant and coolant fluids in the (somewhat artificial) case where the reaction rate is independent of concentration and temperature. While not too realistic for practical application. 

Consequently, a temperature profile develops within the mass which is mainly determined by the substance specific heat conductivity. The temperature profiles of those two limiting cases are presented schematically in Figure 4-7, As the Semenov model is of greater importance to chemical transitions performed in their respective reactors, the following elaboration shall focus on this part of the explosion theory. The other limiting case should be applied when assessing the storage of solid substances with dust explosive or self-reactive properties. 

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