Challenge

Located in Taipei, Taiwan, Republic of China, Formosa Petrochemical (FPCC) refines crude oil, sells refined petroleum products, and produces and sells olefins (including ethylene, propylene, butadiene and BTX) from its naphtha cracking operations. The company also sells electricity, steam and other products generated from its co-generation power plants.

FPCC is the only privately-owned oil refinery in Taiwan and is the second largest gasoline and gas/oil producer on the island. Its refined petroleum products are sold both domestically and overseas. FPCC is also the largest olefins producer in Taiwan.

The company has made pollution control and environmental preservation a key initiative since 1992.  As part of their first ethylene facility at the Mailiao petrochemical complex, FPCC began using innovative technologies for treating ethylene-derived spent caustic to help meet those initiatives.

Solution

Mandated treatment of the spent caustic calls for “deactivation to remove the characteristic of reactivity.” This can be achieved by chemically converting the sulfide to relatively inert sulfur, to insoluble metallic sulfide salts, or to soluble sulfates.  The Zimpro® wet air oxidation process successfully deactivates these sulfide wastes.

Result

Five FPCC facilities currently use the Zimpro® wet air oxidation process to treat their ethylene spent caustic:

• OL-1 plant in Point Comfort, Texas, started up a 21-gpm WAO system in 1994. 
• FOL-1 plant in Mai-Liao, Taiwan, started up a 33-gpm system in 1999.
• FOL-2 plant in Mai-Liao, Taiwan, started up an 81-gpm system in 2000. 
• OL-2 plant in Point Comfort, Texas, started up a 24-gpm system in 2001. 
• New OL-3 ethylene plant in Mailiao, Yun-Lin, Taiwan, will start up a 90-gpm system in 2006