The company was gracious enough: we were given an introduction about the company & the products. The most fascinating was the process. See, PPM manufactures polypropylene pellets which will then be processed into plastic items for packaging, textiles, cutlery, stationary & many more.
Polypropylene is a plastic polymer made from many propylene C3H6 monomers. It is recyclable, resistant to most chemical attacks, light, heat-resistant & has low moisture-absorption rate.
How is it Processed?
Propene undergoes addition reaction with hydrogen gas. The image below shows the process carried out at PPM:
Propylene & hydrogen undergo the purification process to remove foreign components. Nitrogen gas is used as a carrier medium.
Nitrogen carries purified propylene & hydrogen to the reactor where the chemical reaction takes place. Here teal, catalyst & additives (ADT) are added to optimize the reaction. The product of this unit is the polypropylene resin, which is hard solid.
3. Resin degassing
The resin undergoes degassing to remove gaseous by products, including unused propylene, gaseous polypropylene, nitrogen & hydrogen. These gases enter the Recovery Unit where unreacted propylene is sent back into the reactor for processing.
Here the resin undergoes the injection molding process to create fine pellets from the resin block. Power & liquid additives are used in certain amounts to create the desired grade of the pellet.
The pellets enter the 4 different silos (chambers: A, B, C, D) then they are packaged to be sent to other factories for further processing. The importance of the silo is to ensure that the process is continuous.
1. The reactor runs non-stop. The reactor is only stopped for maintenance checks & servicing.
2. Polypropylene is the final product at this plant.
3. The tallest structure is the resin degassing unit.
4. The control center can alternate the product flow to the silo(s) for maximum productivity.
An interesting trip, it was fun to learn about the process. I left out many parts because I'm writing this out of memory (pretty good, eh?), I'll find the time to add in necessary information.
I hope this is an enlightening piece! :)
Thanks to PPM for sharing the knowledge & the fun!