Energy Optimization of Cryogenic Distillation
Dr. Wai Kiong Ng
Karl Kolmetz
Siang Hua Lee
Craig G. Cook
Petronas OGP Technical Services Sdn Bhd
Kuala Lumpur, Malaysia
Prepared for,
DISTILLATION 2005
2005 Spring AIChE Meeting
Atlanta, Georgia
April 10-14, 2005
Abstract
Cryogenic distillation is highly energy intensive. The separation energy for cryogenic distillation in the production of natural gas can be greater than fifty percent of the plant’s total energy requirements. The separation energy for cryogenic distillation in the ethylene production can be greater than twenty-five percent of the plant’s total energy requirements.
The removal of the light components such as hydrogen, methane, ethane and carbon monoxide in cold boxes, demethanizer and deethanizer distillation columns can be optimized to reduce the ten year life cycle cost (return on investment) of the plant. The ten year life cycle cost would be the equipment capital charges and the energy charges during the ten-year equipment life. Additional non-quantized benefits would be environmental and operational. Base and optimized cases will be presented and life cycle cost evaluated.