Application of Response Surface Methodology in Study of the Product Yield Distribution of Thermal Cracking of Atmospheric Gasoil

In order to determine the yield distribution of thermal cracking of gasoil, a pilot plant was
designed and setup. A systematic experimental design was utilized based on CCD (central
composite design). The feed
ow rate, steam ratio and temperature were considered as factors
to design the experiments. Some statistical models were tuned based on the results of conducted
experiments. The models were evaluated with lack-of-t and R-squared tests. The results of
the analysis proved that the models tted well with the experimental results of the considered
products. Based on the experiments and statistical models the pilot plant was optimized in order
to maximize the net prot. At the optimum point coil outlet temperature, the feed
ow rate
and steam ratio were, respectively, equal to 843.8C, 6.02 g/min and 0.46. Regarding these
conditions, the yield of ethylene, propylene and butadiene and rate of coke formation would be
23.82 wt%, 12.13 wt%, 2.42 wt% and 14:44  10????7 g/cm2.sec, respectively.