Comprehensive Guide On Polymerisation Reactor
You can find polymers practically anywhere; in plastic bags, building materials, and functional components for solar cell use. While some polymer materials occur naturally, such as cellulose, or rubber, most synthetic polymers are made through polymerisation. This process occurs in a polymerisation reactor. Here’s more.
Polymerisation is the chemical process of attaching several single molecules, monomers, together. They form these long chain molecules known as polymers. Step-growth polymerisation and chain-growth polymerisation are the two basic types of polyreactions.
– Step-growth Polymerisation
It is a method through which the functional groups of monomers react and interact. The interaction produces dimers, trimers, longer oligomers, and polymers. As a result, to create a lengthy chain, the monomers must have at least two reactive functional groups. A step-growth reaction will result in branching and a cross-linked polymer.
– Chain-growth polymerisation
Chain-growth polymerisation is a three-step reaction. It takes place at the active centre of radicalised or ionic monomers:
The process of forming an active centre in a monomer is initiation. The initiator depends on the process:
- Radical polymerisation employs a radical initiator
- Ionic polymerisation employs a cationic/anionic initiator
- coordination polymerisation employs transition metal complexes
- Thermal polymerisation employs heat
Propagation is when a monomer joins an existing active centre. As a result, it forms a longer polymer molecule with a new activity centre.
Termination propagation will continue until the active centre of the chain carrier vanishes. The polymer molecule can no longer grow at this point.
Fundamentals of Polymerization Reaction Engineering
A polymerisation reactor breaks down into four parts:
- other unique reactors
Chemical reactor manufacturers in India consider heat transfer and fluid flow during construction. It is due to a typical polymerisation system’s high viscosity and exothermicity. For example, the majority of polymerisation reactors include agitators. Tank reactors can stir, and a tower reactor has many blades when used for polymerisation. The primary functions of agitators in a polymerisation reactor are as follows:
– Agitating effect
The agitator’s blades apply pressure on the fluid, causing it to flow more vigorously. To improve heat and mass transfer, you can change the fluid flow pattern by modifying the blades’ form.
– Dispersion effect
Agitation can distribute gas, liquid, and solid in a liquid medium, increasing contact area and heat and mass transfer rate.
– Mixing effect
When there are more than two phases in the feed, proper agitation ensures the following in the reactor:
- homogeneous concentration
– Suspension effect
Agitation can homogeneously maintain solid particles or oil drops in a reaction media. It is especially true for suspension polymerisation techniques, which often use water as the solvent.
The polymerisation process must maintain a homogeneous suspension of monomers through agitation.
– Polymerisation Reactor Design and Operation
The design of a polymerisation reactor begins with the choice of reactor type (batch, semi-batch, or continuous). It then moves on to reactor scale and configuration specifics. Only then can chemical reactor manufacturers handle the operation and control details. There are several types of reactors, including:
- batch reactors (BR)
- semi-batch/semi continuous reactors (SBR)
- plug flow reactors (PFR)
- continuously stirred tank reactors (CSTR)
The choice of reactor stems not only from practical issues such as production scale but also from the polymerisation kinetics. Thus, one section examines reactor design, while another describes reactor operation tactics. Control and optimisation of the reactor are finally addressed.
The construction of the agitator blades and rotation speed must be well established when creating a polymerisation reactor. It is based on the features of the specific polymerisation reaction. It improves agitation function. For example, a high viscosity bulk polymerisation process necessitates extensive mixing and agitation. Besides good mixing, suspension polymerisation necessitates a stable suspension of monomer drops. As a result, agitator design is a critical component of polymerisation reactor design.
An engineer’s role is to create the most efficient and high-quality workable procedures in a competitive world. Industrial polymer production requires a big investment and results in significant sales volume. In addition, recent advancements, in theory, a computing software, and hardware have enabled solid mathematical models to supplement experiments and empirical methodologies.