Plant #2 > MMA
The MMA plant produces about 50,000 tons of MMA using the C4 byproduct generated from the naptha plant as raw material, recording annual sales of about KRW 100 billion. The plant has introduced the direct C4 oxidation method developed in Japan. It is a new technique that has completely resolved the environmental and safety-related problems facing existing plants in the US and Europe. MMA is the raw material for PMMA applied to electric, electronic, and automotive parts, optical fibers, and laser disks, and is used for construction materials such as noise barriers and artificial marbles, and paint, additives used in adhesives, fibers, and medical materials. Recently, its application has greatly expanded to PMMA for LCD monitors.
■ Production process
01 Raw Material Supply
In addition to the main products of ethylene and propylene generated from the Naphtha Cracking Center, the C4 compound, among other byproducts enerated, is used as a raw material for the MMA process. The C4 compound is first sent to the Kumho Petrochemical plant, butadiene is extracted from it, and it is stored again in our tank. The C4 compound stored in this manner is always transferred to the MMA process on a regular basis to be used as the raw material at the MMA plant.
02 TBA Production Process
The process involves producing TBA by having the transferred C4 compound react to water TBA is synthesized through the reaction of isoprene in C4 with water, refined, stored in a tank, and fed to the oxidation reactor. Other non-reacted components of the C4 compound are again transferred to plant #1, where C4LPG is produced by the hydrogenation reaction.
03 100 Section Oxidation and MAL Recovery Process
TBA reacts with the air compressed in gas state in the first oxidation reactor at about 350℃ to become MAL (Metharcrolein) and again reacts with the air compressed in the second oxidation reactor at about 300℃ to create MAA (Methacrylic acid). The produced MMA is cooled and liquefied, and the non-reactive MAL is ecovered for supply to the reactor. The heat generated from the oxidation reactor is recovered in the form of steam, which is used as power for air compressors.
04 200 Section Oxidation and MMA Refining Process
QL is obtained from 100 Section and in 200 Section MAA is extracted from QL. Also, in this Section, the solvent used as the extractive agent is separated from MAA by distillation, and MAA stock solution is obtained.To improve extraction, a Karr column consisting of porous-type reciprocating motion plates is applied and HEP is used as a solvent to increase the level of selection.MAA iseasy to polymerize, especially when facilitated by heat. For this reason, polymerizationinhibitor is supplied to the necessary parts, and condensate is sprayed on the re-boiler to lower the surface temperature of the heating side. Then, the decompression operation is carriedout to lower the emperature of each column.
05 300 Section Ester Reaction and MMA Refining Process
The refined MAA reacts with methanol in the ester reactor tobecome MMA, which is cleared of impurities and moisture, and refined up to the purity level of over 99.8% to become a product. MMA is stored in the tank at about 10℃ for delivery.
06 400 Section MMA Storage/Shipping
In this section, MMA is stored and transported. It consists of 2 inspection tanks(FB-412, 413), 1 storage tank(FB-414), and transport equipment. For olymerization inhibition, it is essential that moisture should not be mixed with the product. For this purpose, a dehumidifier should be installed at the vent of each tank so that olymerization may be inhibited through circulation and cooling of products at each tank. When moisture is removed from the product, the product is transferred to the product storage tank after being subjected to the process of cooling at 60℃ by cooled nitrogen.
