Method for improving productivity and process stability in styrene manufacturing system having multiple reactors connected in series

1. A method for improving productivity and process stability in a styrene preparation process system comprising:

Providing first (R- 1 ), second (R- 2 ), and third (R- 3 ) adiabatic reactors connected in series, the first adiabatic reactor (R- 1 ) having a first heat exchanger (HX- 1 ) located downstream and a first furnace (F-1) located upstream, the second adiabatic reactor (R- 2 ) having a second heat exchanger (HX- 2 ) located downstream and a second furnace (F-2) located upstream, and the third adiabatic reactor (R- 3 ) having a third heat exchanger (HX- 3 ) located downstream and a third furnace (F-3) located upstream;

diverging a portion of a raw material containing steam and ethylbenzene downstream from the third heat exchanger (HX- 3 ) to produce a diverged raw material;

diverging a portion of a steam having a temperature in the range of 800-900° C. discharged from the first furnace (F-1) to produce a diverged steam;

mixing the diverged raw material and the diverged steam to produce a first mixture; and

injecting the first mixture at a point (P) downstream from the second adiabatic reactor (R- 2 ) and upstream from the second heat exchanger (HX- 2 ) or injecting the first mixture at a point (Q) downstream from the second heat exchanger (HX- 2 ) and upstream from the third adiabatic reactor (R- 3 ).

2. The method according to claim 1 , wherein the third adiabatic reactor (R- 3 ) has a volume 2-5 times greater than each of the first (R- 1 ) and second (R- 2 ) adiabatic reactors.

3. The method according to claim 1 , wherein the diverged raw material is 15-20 vol % of a total amount of the raw material containing the ethylbenzene and the steam.

4. The method according to claim 1 , wherein the diverged steam is 15-20 vol % of a total amount of the steam feed.