DESIGN AND STUDY OF MANUFACTURING OF POLYESTER PLANT USING PTA AND MEG

Abstract

Polyester is a category of polymers which contain the ester functional group in their main chain. Although
there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene
terephthalate (PET). A chemical reaction bonding monomers together to make a polymer is called polymerization.
Polymers are substances whose molecules have high molar masses and are composed of a large number of repeating
units. Pure Terephthalic Acid (PTA) and Mono Ethylene Glycol (MEG) are mixed to produce oligomer and water in the
Esterification section. The oligomer is then pumped to polymerisation section after addition of chemicals namely
catalyst, TiO2, DEG & glycol. The oligomer is converted to polymer through polymerisation reaction and is sent to
spinning and the spin product is sent for drawing after which it is baled and cut. After cutting, the product is sent to
warehouse. We started with the study of polyester and studies its manufacturing process available. We also formed out
its application and uses and its supply and demand of polyester. Also advantages and disadvantages here with we come
across the present demand in the market of polyester and the current supply rate of polyester. The proposed work in this
project is the plant study and material balance of polyester plant installed in Reliance Industries Pvt. Ltd. in Patalganga,
where we study the manufacturing of polyester by using its raw materials pure terephthalic acid and mono ethylene
glycol. Also the production of polymer is a two step reaction process that is esterification and polycondensation. The
production of polyester polymer is a two step reaction process i.e. Esterification and Polymerisation. Esterification is the
formation of monomer and polycondensation is the formation of oligomer and polymer chain building. The esterification
reaction is technically an acid –base reaction that forms salt and water. Terephthalic Acid (TPA) is the acid and
Ethylene Glycol (EG) is the base and the monomer DiHydroxyEthyl Terephthalate, DHET is the salt with water also
being a product of the reaction. Polycondensation is the actual “chain building” step in the making of polyester polymer.
The reaction in order to proceed forward, requires the addition of a catalyst, typically antimony, as well as heat and
vacuum. The chemical linkage between two molecules forming one large molecule.Material balance importance first step
when designing a new process or analysing. They are almost always pre requisite to all other calculation in the solution
of process engineering a material balance is an accounting for material. Thus material balance are often compared to
the balancing of current account. They are used in industry to calculate mass flow rates of different stream entering or
leaving chemical or physical process.