Analysis of Energy Consumption of Catalytic Cracking Unit after Switching to Full Regeneration System and Optimizing Measures

Sinopec Luoyang Company′s catalytic cracker originally had a wax oil processing capacity of 200×104t/a.Between 2000 and 2001,the unit′s heavy oil processing capacity stood at 140×104t/a after the company introduced UOP technology in the unit.On May 5,2010,the company upgraded the regenerating system of the unit to full regeneration from conventional regeneration.That upgrade improved product distribution and raised the value added to products as well as product yields.After the full regeneration system was introduced,carbon on regenerated catalysts dropped by 0.10% and coke yield dropped by about 0.25%.However,the overall energy consumption of the catalytic cracker increased by about 11kg of oil equivalent per ton of feedstock.Increased electric power consumption(an increase of about 3.63kg of oil equivalent per ton) was the main reason for the rise in overall energy consumption of the unit.In addition,the output of steam produced using residual heat dropped.Researchers analyzed the factors affecting the energy consumption of the unit and proposed some measures to improve the energy efficiency of the unit having regard to actual production conditions,including achieving the stable and full-capacity operation of the two fans,saving electric power,optimizing operation,increasing the amount of heat recovered and reducing the yield of coke.As a result,the unit′s energy consumption dropped to some extent.The researchers also suggested adding a new main fan as well as ancillary gas turbines and revamping the residual heat boiler to adapt to the full regeneration system to achieve the stable operation of the unit and reduce energy consumption.