Passivation of coker furnaces using combined mechanical and chemical means

Abstract

Disclosed herein are methods and systems for removing hydrocarbon deposits or coking and minimizing fouling in coker furnaces. The method includes displacing at least one cleaning pig in a coker furnace tubing, introducing a displacement fluid into the coker furnace tubing after the at least one cleaning pig, introducing an inhibition composition into the coker furnace tubing after the displacement fluid, wherein the inhibition composition comprises a first organo sulfate compound with a divalent cation diluted in a hydrocarbon liquid, introducing a coker feed into the coker furnace tubing, and introducing a second organo sulfate compound with a divalent cation into the coker feed.

What is claimed is: 
     
         1 . A method comprising:
 displacing at least one cleaning pig in a coker furnace tubing;   introducing a displacement fluid into the coker furnace tubing after the at least one cleaning pig;   introducing an inhibition composition into the coker furnace tubing after the displacement fluid, wherein the inhibition composition comprises a first organo sulfate compound with a divalent cation diluted in a hydrocarbon liquid;   introducing a coker feed into the coker furnace tubing; and   introducing a second organo sulfate compound with a divalent cation. into the coker feed.   
     
     
         2 . The method of  claim 1 , wherein the inhibition composition is introduced into the coker furnace tubing in between two pigs travelling at a velocity from about 0.1 meter per second to about 1 meter per second. 
     
     
         3 . The method of  claim 1 , wherein the inhibition composition is introduced into the coker furnace tubing and then allowed to soak within the coker furnace tubing from about 1 minute to about 3 hours. 
     
     
         4 . The method of  claim 1 , wherein the introducing the inhibition composition is performed using foaming pigs travelling at a velocity from about 0.2 meters per second to about 0.3 meters per second. 
     
     
         5 . The method of  claim 1 , wherein the inhibition composition in contact with the coker furnace tubing forms a protective coating having a thickness of about 6.35 microns to about 10 microns. 
     
     
         6 . The method of  claim 1 , wherein the first organo sulfate compound and the second organo sulfate compound each comprise a calcium or magnesium salt of dodecyl benzene sulfonate. 
     
     
         7 . The method of  claim 1 , wherein the first organo sulfate compound and the second organo sulfate compound each comprise isopropyl naphthalene sulfonate. 
     
     
         8 . The method of  claim 1 , wherein the first organo sulfate compound and the second organo sulfate compound each comprise lignosulfonate. 
     
     
         9 . The method of  claim 1 , wherein the first organo sulfate compound and the second organo sulfate compound each comprise a combination of a calcium or magnesium salt of dodecyl benzene sulfonate, isopropyl naphthalene sulfonate, and lignosulfonate. 
     
     
         10 . The method of  claim 1 , wherein the first organo sulfate compound is diluted in the hydrocarbon liquid in a volume ratio from about 3:7 to about 1:9, wherein the hydrocarbon liquid comprises diesel. 
     
     
         11 . The method of  claim 1 , wherein the inhibition composition has a pH from about 7.1 to about 9.5. 
     
     
         12 . The method of  claim 1 , wherein the inhibition composition has a pH from about 7.1 to about 8.0. 
     
     
         13 . The method of  claim 1 , wherein the second organo sulfate compound is introduced into the coker feed in a concentration of from about 25 ppm to about 250 ppm. 
     
     
         14 . The method of  claim 1 , wherein the second organo sulfate compound is introduced into the coker feed in a concentration of from about 30 to about 75 ppm. 
     
     
         15 . A method comprising:
 displacing at least one cleaning pig in a coker furnace tubing;   introducing a displacement fluid into the coker furnace tubing after the cleaning pig;   introducing an inhibition composition into the coker furnace tubing after the displacement fluid, wherein the inhibition composition comprises a calcium or magnesium salt of dodecyl benzene sulfonate diluted in a hydrocarbon liquid;   introducing a coker feed into the coker furnace tubing; and   introducing an additional quantity of the calcium or magnesium salt of dodecyl benzene sulfonate into the feed intermittently.   
     
     
         16 . The method of  claim 15 , wherein the calcium or magnesium salt of dodecyl benzene sulfonate is diluted in the hydrocarbon liquid in a volume ratio from about 3:7 to about 1:9, wherein the hydrocarbon liquid comprises diesel. 
     
     
         17 . The method of  claim 15 , wherein the inhibition composition has a pH from about 7.1 to about 8.0. 
     
     
         18 . The method of  claim 15 , wherein the additional quantity of the calcium or magnesium salt of dodecyl benzene sulfonate is introduced into the coker feed in a concentration of from about 25 ppm to about 250 ppm. 
     
     
         19 . The method of  claim 15 , wherein the additional quantity of the calcium or magnesium salt of dodecyl benzene sulfonate is introduced into the coker feed in a concentration of from about 30 to about 75 ppm. 
     
     
         20 . A method comprising:
 displacing at least one cleaning pig in a coker furnace tubing;   introducing a displacement fluid into the coker furnace tubing after the at least one cleaning pig;   introducing an inhibition composition into the coker furnace tubing after the displacement fluid, wherein the inhibition composition has a pH from about 7.1 to about 8.0 and comprises a calcium or magnesium salt of dodecyl benzene sulfonate diluted in diesel in a volume ratio from about 3:7 to about 1:9;   introducing a coker feed into the coker furnace tubing; and   introducing an additional quantity of the calcium or magnesium salt of dodecyl benzene sulfonate in a concentration of from about 30 to about 75 ppm into the coker feed intermittently.