Marty, CITGO sign caretaker since 1965.Marty, CITGO sign caretaker since 1965.
   Lemont Refinery
    CITGO Clean Skies Initiative
Clean Stack Scrubs Air Clean
Another step to cleaner air

The CITGO Lemont Refinery is pleased to introduce an upgrade to the plant. It's the newest component of the Clean Skies Initiative, our effort to minimize the environmental impact of the refinery process. "Clean Stack" is a new process designed to reduce some of our emissions. The result will be a significant improvement in air quality.
What is Clean Stack?

It boils down to steam

The most noticeable effect of Clean Stack--the Wet Gas Scrubber--will be a plume of steam that could stretch several hundred feet across the sky. Just like the steam that comes from your teapot, a steam iron or a sauna, the Clean Stack plume is nothing more than tiny droplets of condensed water vapor. Nearly all of the pollutants from the vapor will be cleansed before it is released into the air.
  • It's a combination of two high-tech units: the Selective Catalytic Reduction Unit and the Wet Gas Scrubber.
  • Together, they will reduce the emissions that result from the manufacture of gasoline for your car.
  • These improvements represent a $142 million investment and a continuing commitment to our environment.

What does it do?

  • First, chemical reactions take place that eliminate certain compounds from refinery gases.
  • Next, stack gases are scrubbed, much as rain washes pollen and fine dust particles from the air.

What are the benefits to you and the enviroment?

  • 98% reduction of emissions of sulfur dioxide (SO2)
  • 94% reduction of emissions of nitrogen oxide (NOx)
  • 96% reduction of emissions of particulate matter (dust)

How does it affect you?

  • The only noticeable difference to the refinery is a new stack and plume. It is just like the steam you see coming from a teapot of boiling water.

What are the benefits to the community?

  • 1,500 union construction jobs; $60 million in contracts
  • An additional $3 million spent with local vendors
  • Annual operational costs of $15 million, primarily for electric power and caustic purchased from local suppliers
  • A viable plant, securing jobs for 525 CITGO employees, their families and hundreds of support contractors, contributing to a strong local economy

Questions and Answers About Clean Stack

Clean Stack comes to Lemont

CITGO's Don Harden, chief operator, gestures toward the Clean Stack during its construction phase. During the three years of construction, 1,500 union workers helped build the $142 million facility. We're making a good refinery better for the long term.

What will neighbors notice?

The process will produce a plume of water vapor, which will be much more noticeable, especially in winter.

Will this project reduce odors?

Yes. In a refinery, one significant source of odor is sulfur dioxide (SO2) from the FCC stack. Clean Stack essentially will eliminate that source.

How do you know that the system is working?

The system is closely monitored by CITGO; data is monitored continuously. Reports are submitted to EPA to confirm that the equipment is working as designed.

What will happen to the particulate matter and dust that is scrubbed from the process?

The solids are recovered and dried, contained and managed in a properly licensed landfill.

Are there any other components to this process?

A Purge Treatment Unit will treat waste water generated from the Clean Stack process. The resulting treated water is discharged in accordance with the permit issued by Illinois EPA.
CITGO Clean Skies Initiative
Nearly $1 billion for clean-air improvement

Clean Stack is the latest in a series of CITGO efforts to minimize impact on the environment by using the best available technology. It's part of a long-term Clean Skies Initiative that dates to 1997, when CITGO began operating the Lemont refinery.

1997 Clean Burners I -- $650,000
Low NOx burners installed on coker heaters
1999 Clean Tank -- $500,000
Domes installed on storage tanks
2000 Clean Burners II -- $1.625 million
Low NOx burners installed on crude heaters
2003 Clean Gasoline Unit -- $248 million
ISAL Gasoline Desulfurization
2006 Clean Burners III -- $2.5 million
Low NOx burner installed on Auxilliary Boiler
2007 Clean Stack -- $142 million
Wet Gas Scrubber and Selective Catalytic Reduction Unit
2008 Clean Sulfur Stack -- $98 million
Tail Gas Unit for sulfur recovery
2010 Clean Diesel Unit -- $500 million
Ultra Low-Sulfur Diesel

CITGO Lemont Refinery
135th & New Avenue
Lemont, IL 60439

For information contact: (630) 257-7761

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