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Tubular reactors process applications

Application The high-pressure Lupotech TS or TM tubular reactor process is used to produce low-density polyethylene (LDPE) homopolymers and EVA copolymers. Single-train capacity of up to 400,000 tpy can be provided. [Pg.149]

Apart from the different t) es of reactors used, the autoclave and tubular reactor processes are very similar. The two types of reactors produce, however, products which have a different molecular structure and are, therefore, used in different product applications. [Pg.38]

Table I provides an overview of general reactor designs used with PS and HIPS processes on the basis of reactor function. The polymer concentrations characterizing the mass polymerizations are approximate there could be some overlapping of agitator types with solids level beyond that shown in the tcd>le. Polymer concentration limits on HIPS will be lower because of increased viscosity. There are also additional applications. Tubular reactors, for example, in effect, often exist as the transfer lines between reactors and in external circulating loops associated with continuous reactors. Table I provides an overview of general reactor designs used with PS and HIPS processes on the basis of reactor function. The polymer concentrations characterizing the mass polymerizations are approximate there could be some overlapping of agitator types with solids level beyond that shown in the tcd>le. Polymer concentration limits on HIPS will be lower because of increased viscosity. There are also additional applications. Tubular reactors, for example, in effect, often exist as the transfer lines between reactors and in external circulating loops associated with continuous reactors.
In this chapter the simulation examples are described. As seen from the Table of Contents, the examples are organised according to twelve application areas Batch Reactors, Continuous Tank Reactors, Tubular Reactors, Semi-Continuous Reactors, Mixing Models, Tank Flow Examples, Process Control, Mass Transfer Processes, Distillation Processes, Heat Transfer, and Dynamic Numerical Examples. There are aspects of some examples which relate them to more than one application area, which is usually apparent from the titles of the examples. Within each section, the examples are listed in order of their degree of difficulty. [Pg.279]

If AW AW the process of finding a linear-mixture basis can be tedious. Fortunately, however, in practical applications Nm is usually not greater than 2 or 3, and thus it is rarely necessary to search for more than one or two combinations of linearly independent columns for each reference vector. In the rare cases where A m > 3, the linear mixtures are often easy to identify. For example, in a tubular reactor with multiple side-injection streams, the side streams might all have the same inlet concentrations so that c(2) = = c(iVin). The stationary flow calculation would then require only AW = 1 mixture-fraction components to describe mixing between inlet 1 and the Nm — I side streams. In summary, as illustrated in Fig. 5.7, a turbulent reacting flow for which a linear-mixture basis exists can be completely described in terms of a transformed composition vector ipm( defined by... [Pg.186]

Amongst the assumptions we have made in developing the model are the following that Pick s law is applicable to the diffusion processes, the gel particles are isotropic and behave as hard spheres, the flow rate is uniform throughout the bed, the dispersion in the column Ccui be approximated by the use of an axial dispersion coefficient cuid that polymer molecules have an independent existence (i.e. very dilute solution conditions exist within the column). Our approach borrows extensively many of the concepts which have been developed to interpret the behaviour of packed bed tubular reactors (5). [Pg.26]

The hydrodynamic factors that influence the plasma polymerization process pose a complicated problem and are of importance in the application of plasma for thin film coatings. When two reaction chambers with different shapes or sizes are used and when plasma polymerization of the same monomer is operated under the same operational conditions of RF power, monomer flow rate, pressure in the reaction chamber etc., the two plasma polymers formed in the two reaction chambers are never identical because of the differences in the hydrodynamic factors. In this sense, plasma polymerization is a reactor-dependent process. Yasuda and Hirotsu [22] systematically investigated the effects of hydrodynamic factors on the plasma polymerization process. They studied the effect of the monomer flow pattern on the polymer deposition rate in a tubular reactor. The polymer deposition rate is a function of the location in the chamber. The distribution of the polymer deposition rate is mainly determined by the distance from the plasma zone and the... [Pg.176]

Although the early literature described the application of a tubular reactor for the production of SBR latexes(1), the standard continuous emulsion polymerization processes for SBR polymerization still consist of continuous stirred tank reactors(CSTR s) and all of the recipe ingredients are normally fed into the first reactor and a latex is removed from the last one, as shown in Figure 1. However, it is doubtful whether this conventional reactor combination and operation method is the most efficient in continuous emulsion polymerization. As is well known, the kinetic behavior of continuous emulsion polymerization differs very much according to the kind of monomers. In this paper, therefore, the discussion about the present subject will be advanced using the... [Pg.125]

The PFR tubular reactor is used for both liquid and gas phases. The reactor is a long vessel with feed entering at one end and product leaving at the other end. In some applications the vessel is packed with a solid catalyst. Some tubular reactors run adiabatically (i.e., with no heat transferred externally down the length of the vessel). The heat generated or consumed by the reaction increases or decreases the temperature of the process... [Pg.434]

The achievable fluxes through membranes, J, were designated in [35] as area time yields (ATY, in molm-2s). Figure 12.4 provides an estimation of the current state regarding the possibility of matching the two processes. For a wide range of membranes under consideration, the required ratios of membrane area to reactor volume (Am/Vr) are between 10 and 100 nr1. These values allow to estimate that the diameter of applicable cylindrical tubular reactors should be between 0.04 and 0.4 m. These appear to be reasonable values for industrial applications, and indicate that matching of the two processes under consideration is achievable with currently available membranes. [Pg.368]

Description Ethylene, initiator and, if applicable, comonomers are fed to the process and compressed to pressures up to 3,100 bar before entering the tubular reactor. In the TS mode, the complete feed enters the reactor at the inlet after the preheater in the TM mode, part of the gas is cooled and quenches the reactor contents at various points of injection. [Pg.149]

Application To produce low-density polyethylene (LDPE) and EVA copolymers by an unique high-pressure clean tubular reactor (CTR) process. Single-line capacities up to 400 mtpy are available. [Pg.94]

Different types of reactors are utilized for a wide variety of pyrolysis applications, including processing of waste plastics. The worldwide waste plastic pyrolysis systems utilize the fixed-bed designs of vertical shaft reactors and dual fluidized-bed, rotary kiln and multiple hearth reactor systems. The type of reactor used is chiefly based on material to be pyrolyzed and expected products from the pyrolysis. Stainless steel shaking type batch autoclave and stainless steel micro tubular reactors have also been used extensively [14]. Fluidized-bed reactors have been extensively used in producing raw petrochemicals from the pyrolysis of waste plastics [22, 24]. [Pg.375]

Theonly important current application of tubular reactors in polymer syntheses is in the production of high pressure, low density polyethylene. In tubular processes, the newer reactors typically have inside diameters about 2.5 cm and lengths of the order of I km. Ethylene, a free-radical initiator, and a chain transfer agent are injected at the tube inlet and sometimes downstream as well. The high heat of polymerization causes nonisothermal conditions with the temperature increasing towards the tube center and away from the inlet. A typical axial temperature profile peaks some distance down the tube where the bulk of the initiator has been consumed. The reactors are operated at 200-300°C and 2000-3000 atm pressure. [Pg.369]

This approach was applied to the Williams-Otto process (Balakrishna and Biegler, 1993). In previous studies, this process was optimized with a CSTR reactor followed by waste and product separators and a recycle stream. The application of (P12) to this problem led to a significantly improved process, particularly when the separation costs p ) were low enough to allow coupled reaction and separation. Without separation, the optimal network is a single PFR with twice the return on investment of previous studies. Allowing for separation leads to a tubular reactor with sidestream separators to remove product and waste as they are created. The resulting process objective has a further fivefold improvement. [Pg.290]

Tubular Reactors Reactor Types and Selected Process Applications... [Pg.3151]


See other pages where Tubular reactors process applications is mentioned: [Pg.27]    [Pg.121]    [Pg.291]    [Pg.240]    [Pg.282]    [Pg.43]    [Pg.180]    [Pg.121]    [Pg.141]    [Pg.18]    [Pg.405]    [Pg.228]    [Pg.22]    [Pg.121]    [Pg.9]    [Pg.255]    [Pg.3164]   
See also in sourсe #XX -- [ Pg.3155 , Pg.3156 , Pg.3157 , Pg.3158 , Pg.3159 , Pg.3160 , Pg.3161 , Pg.3162 , Pg.3163 ]




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