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Influence of turbulent mixing on fast polymerization reactions

“…When fast polymer synthesis processes are carried out in classical stirred tank reactors, in which such processes generally occur in the diffusion region (τ ch < τ mx ), it is problematic to arrange the highly effective mixing of reactants and, as a result, the performance characteristics of the product are deteriorated. Processes of this type, as has been noted earlier, must be carried out in a flow confined by a repulsive wall, that is, in tubular turbulent jet reactors5, 11 (Fig. 2).…”

“…Tubular turbulent reactors with geometrically identical elements of the divergent–convergent design repeated along the axis [Fig. 2(b)] turned out to be effective in this respect because they provide a significant (by an order of magnitude and greater) increase in D t and allow a high level of flow turbulence to be maintained along the reaction zone of any length 6, 7, 11. Their distinctive feature is the possibility of reaching a required intensity of mixing and heat transfer at significantly (a few times) lower flow velocities.…”

“…This is seen from the figure, which shows a change in the turbulent kinetic energy and its dissipation rate depending on the channel geometry. Based on this concept, a new type of reactor (tubular devices that operate in the high‐turbulence plug‐flow mode5, 11 and are used with extremely high cost performance and engineering advantages in the manufacture of polymeric products) was designed.…”

“…In this case, ideal (or nearly ideal) conditions of occurrence of chemical processes can be provided for each stage. It can be achieved in a turbulent prereactor of the divergent–convergent design11 for the first step and in a stirred tank polymerizer reactor for the second, slow step. Using the prereactor of the divergent–convergent design, the reactant micromixing time is always shorter that the residence time of the reaction mixture (τ mx < τ r ).…”

Intensification of gas-liquid processes in tubular turbulent apparatus

“…These requirements are satisfied in the optimal way by small-size tubular turbulent apparatus of diffuser3 confuser design [1], which are highly efficient in fast chemical and mass-exchange physical processes in liquid3gas systems and, in particular, chlorination of butyl rubber with molecular chlorine, preparation of a homogeneous gas3liquid mixture for obtaining ethylene3propylene rubbers, chlorination and hydrochlorination of ethylene, production of nitrogen fertilizers, etc. [2,3].…”