Heat integrated PFR

Agreda, V.H., L. R, Partin, W.H. Heise, 1990, High-purity methyl acetate via Reactive Distillation, Chem. Eng. Progr., 86, Febmary, 40-46 Allen, D.T., K., S. Rosselot, 1996, Pollution Prevention for Chemical Processes, Willey Bildea, C. S., A. C. Dimian, 1998, Stability and Multiplicity Approach to the Design of Heat-Integrated PFR, AIChE J, vol. 44,2703-2712... 

In this way another structure is obtained, as presented in Fig. 13.27, which is more general for industrial applications. This will be called heat-integrated PFR. This generic structure has been studied by Bildea Dimian (1998, 2000) from the point of state-multiplicity, stability, and controllability. The investigation has put in evidence the close link between design and controllability. 

Without heat integration The MINLP was first performed in one PFR as suggested at Level 2 and the solution yielded a profit of 17.791 M /a. The selectivity of allyl chloride production with respect to the consumption of CI2 is very low (Table la) not only because the number of passes of propene through the reactor is small due to very high consumption of utilities but also because of the very wide temperature range in Figure 4a Reactor /separator trajectory the reactor. (See the rapid decrease of without heat integration. the molar profit in Fig. 4a.)... 

Simultaneous heat integration The MINLP was repeated for reactors with a side feed stream in order to decrease the temperature range in the reactor. The profit was increased to 20.393 M /a by a two PFR with a side cold shot The selectivity significantly increased (from 0.81 to 0.95). 

Tubular Reactors (PFR/PBR). When the heat flow vanes along the length of the reactor, such as would be the case in a tubular flow reactor, we must integrate the heat flux equation along the length of the reactor to obtain the total heat added to the reactor. 

The integrator tool is used to derive a. simulation model for Aspen Plus from the initial PFD. Here, the user has to perform two decisions. While the heating step can be mapped structurally 1 1 into the simulation model, the user has to select the most appropriate block for the simulation to be performed. Second, there are multiple alternatives to map the PFR. Since the most straightforward 1 1 mapping is not considered to be sufficient, the... 

PHENTX, SUPERPHENIX and PFR are so-called pool reactors, whereas the other three projects are loop reactors. In a pool reactor, the whole primary heat transfer system including main pumps and intermediate heat exchangers is integrated into the reactor vessel (pool), while the loop reactors have parallel primary sodium heat transfer circuits (loops) with the main heat transfer components external to the reactor vessel. The secondary heat transfer system, installed between primary system and water/steam system for safety reasons, is practically identical in both cases. It also consists of three parallel circuits. Live steam conditions and the achievable efficiency are very similar in all plants 500°C, 165 bar, 40%. These are close to the conditions of coal-fired stations. 

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