In fluid coking $($see Figure below$),$ bitumen is sprayed into a hot fluidized bed of coke particles to form thin liquid

films. At high reactor temperatures, these films undergo thermal cracking reactions to form fresh coke and volatile

products. The mass of fresh coke deposited on the hot coke particles is usually about $3wt\%$ per pass through the

reactor. Based on the data given below, estimating the following:

Coke circulation rate.

Required volume of the coker $($assuming total volume being twice of the coke volume in the coker$).$

Minimum volume of the burner $(20\%$ greater than the volume of the coke in the burner$).$

Flowrate of coke product exiting the system and the ultimate coke yield of the system.

DATA:

Feed to coker $=2,000bb\frac{l}{h}({10}^{3}K\frac{g}{m^3})$

Coke particle density $=1450K\frac{g}{m^3}$

Coke bulk density $=800K\frac{g}{m^3}$

Coke heat capacity $=1\mathrm{.}6K\frac{J}{K}g$

Coke heat of combustion: $29\mathrm{.}5M\frac{J}{k}g$

Coke yield in coking $=22\%$ mass

Coke average residence time in coker $=6$ minutes

Coke average residence time in burner $=7$ minutes

Steam temperature $=180C,$ saturated

Steam flow: enough to keep fluidization

Ambient air temperature $=15C$

Ambient air relative humidity $(RH)=60\%$

Operating temperature of coker $=530C$

Operating temperature of burner $=630$CAsphaltenes are defined as the material that precipitates from crude oil or bitumen when a large excess of n$-$alkane solvent is added. Hildebrand Solubility Parameters for n$-$alkanes

Solvent $\backslash$delta $1,$ MPa$1/2$

n$-$Pentane $14\mathrm{.}4$

n$-$Hexane $14\mathrm{.}9$

n$-$Heptane $15\mathrm{.}3$

n$-$Dodecane $16\mathrm{.}0$

If the asphaltene in Lloydminster heavy oil has a solubility parameter of approximately $16\mathrm{.}5$ MPa$1/2,$which of these n$-$alkanes will precipitate the most asphaltene?