Tubular reactors single stage

A tubular reactor will likely deviate from plug flow in most practical cases, e.g., due to backmixing in the direction of flow, reactor internals, etc. A way of simulating axial backmixing is to represent the reactor volume as a series of n stirred tanks in series. The steady-state solution for a single ideal CSTR may be extended to find the effluent concentration after two ideal CSTRs and then to n ideal stages as... 

Description A typical MTBE/ETBE unit using FCC cut is based on a single-stage scheme, with a tubular (1) and an adiabatic (2) reactor. The front-end reactor uses the proprietary water-cooled tubular reactor (WCTR). The WCTR Is a very flexible reactor and can treat all C cuts on a once-through basis. 

In a packed catalytic tubular reactor, reactants are converted to products via chemical reaction on the internal surface of the catalyst. This problem was described in detail for a single isolated pellet. At this stage of the design, one seeks an expression for the volume-averaged rate of reactant consumption within... 

Here, we present the basic idea for the formulation of one-dimensional distributed models for a single-input, single-output, and single-reaction tubular reactor. Axial dispersion is neglected in this preliminary stage then, it will be introduced and discussed later in this chapter. 

For some purposes it is adequate to assume that a battery of five or so CSTRs is a close enough approximation to a plug flow reactor. The tubular flow reactor is smaller and cheaper than any comparable tank battery, even a single shell arrangement. For a first order reaction the ratio of volumes of an n-stage CSTR and a PFR is represented by... 

FIGURE 13.1 Types of fixed bed reactors, (a) Axial flow fixed bed reactor Up or down flow, single or multi-stage, with or without inter-stage cooling, single or multi-tubular, (b) Radial flow fixed bed reactor Radially inward or outward flow, straight or reverse flow (direction of inlet and outlet is same or opposite to each other). 

In the case of refinery cuts from FCC units, having a relatively low isobutene concentration (Table 11.2), the plant layout is less sophisticated because it is sufficient to achieve 90-95% of isobutene conversion in this case the plant configuration is based on a single reaction stage with tubular and adiabatic reactors in series with intermediate cooling. 

---