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.

Claims

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.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] These drawings illustrate certain aspects of some of the embodiments of the present disclosure and should not be used to limit or define the method.

[0006] FIG. 1 is a schematic illustration of a coker furnace according to embodiments of the present disclosure.

DETAILED DESCRIPTION

[0007] The present disclosure generally relates to systems and methods for removing hydrocarbon deposits or coking and minimizing fouling in coker furnace tubing. Example methods may include displacing at least one cleaning pigs inside a coker furnace tubing, then introducing a displacement fluid (e.g., spacer fluid), then introducing an inhibition composition, and finally introducing an antifouling composition along with the hydrocarbon liquid during operation to minimize formation of hydrocarbon deposits. The introduction of the fluid may be performed by any method to introduce a fluid including pumping, injecting, pushing, or any combination, for example.

[0008] FIG. 1 is a general schematic illustration of a coker furnace in accordance with embodiments of the present disclosure. FIG. 1 illustrates a typical flow scheme 100 of a coker furnace having a source of a hydrocarbon feed stock. The hydrocarbon feed stock comprises vacuum residue from a vacuum distillation unit 102a, and/or an associated storage tank for vacuum residue 102b. Vacuum residue, which is a heavy hydrocarbon having a boiling point typically above 1050 F. (565 C.), contains coke precursors, such as asphaltenes and other high boiling resins and wax materials. Most vacuum residue contains other impurities, such as, but not limited to, metals, filterable solids, and corrosion products obtained from upstream units. The coker acts as a carbon rejection process, such that the valuable distillates like heavy coker gas oil, light coker gas oil, coker naphtha, LPG, etc. are recovered post-cracking in coker unit drums 104.

[0009] In some embodiments, vacuum residue is heated to the necessary reaction temperature of about 930 F. (500 C.) in coker charge heater(s) 106. Coke formation is an endothermic reaction during cracking, such that there will generally be a drop in temperature by about 10 C. to about 30 C. While coking is the requirement to reject carbon, it is not desired in the charge heaters 106 or in pre-heat exchangers 108 as any such deposit formation other than coker unit drums 104 will reduce the on-stream factor of the unit resulting in loss of unit capacity and refining margin. Hence, it is important to keep heating surfaces as clean as possible to prolong the operation. Therefore, in some embodiments, the inhibition composition of the present disclosure may be doped either by directly injecting it into feed at suitable locations, and/or through velocity steam lines that are added into coker feed to raise the velocity of hydrocarbon feed in the heater.

[0010] In some embodiments, the vacuum residue, along with previously stored material from offsite tank 102b is pumped to a coker complex, where it gets heated in a series of preheat exchanger(s) 108 to a temperature of about 570 F. (300 C.), and is subsequently routed to coker main fractionator 110. In some embodiments, a portion of the heaviest boiling material that gets dropped in the column during fractionation gets mixed with feed and/or vacuum residue. The mixed stream is then fed to coker charge heater 106, wherein the feed mix is heated to reaction temperature.

[0011] In some embodiments, to minimize coking, the inhibition composition can be added to the velocity steam (shown by the dashed lines coming from point A in FIG. 1) at three different places of the charge heater 112, namely at the convection coils, at the inlet to the radiation section, and/or at the remaining few coils in the radiation where maximum heat flux is expected (and also cracking occurs). Partially cracked material from heater is then fed to one of the coke drums 104 to reject coke. The overhead vapors from the coke drum(s) 104 is/are routed to the main fractionating column 110 to get desired products that are separated based on cut points (i.e. distillation range). In some embodiments, the inhibition composition is provided by the pump discharge from a dosing pump 112. In some embodiments, the inhibition composition is stored in a storage tank 114.

[0012] The systems and methods of the present disclosure may include displacing at least one cleaning pig in the coker furnace tubing. The cleaning pig may be used to mechanically remove hydrocarbon deposits from the inner walls of the coker furnace tubing. The cleaning pig may be any pipeline intervention gauge (pig) capable of mechanically removing scale, deposits, and contaminants within a tubing ensuring unobstructed flow including utility pig, mandrel pig, batching pig, dewaxing pig, configuration pig, magnetic pig, foam pig, brush pig, caliper pig, passive bypass pig, criss cross scraper pig, pipeline sphere, gel pig, camera pig, spherical pig, pipeline pig, and diamond blade pig, for example. Optionally, the cleaning pig may be equipped with sensors and tools to inspect the furnace tubing for damage, corrosion, cracks, and other anomalies.

[0013] Each coker furnace tubing or coil may be connected to a pig launcher and a pig receiver to move the cleaning pig back and forth to ensure coking is removed from the inner wall of the coker furnace tubing. Therefore, each one of the two cleaning pigs may have fluid on each side. The fluid may be any fluid capable of displacing a cleaning pig including water, diesel, nitrogen, or any combination thereof. The fluid in between the two cleaning pigs helps in removing coking and any debris the cleaning pigs may have removed. The other fluid on the other side of each of the two cleaning pigs is a displacing fluid that pushes the cleaning pig and removes any remaining debris or coating that the fluid in between the two cleaning pigs may have left behind. For example, if the coker furnace tubing has a 5 inches internal diameter, a 2 inch in diameter cleaning pig may be launched at first at the pig launcher with any fluid capable of pushing the first cleaning pig and removing the scrapped coking behind it such as water with a second cleaning pig to push the fluid that pushes the 1.sup.st cleaning pig. A displacement fluid is used to push the second cleaning pig and remove any debris that the two cleaning pigs and the fluid in between the two cleaning pigs may have left behind. Both of these cleaning pigs should be pushed to travel at a velocity high enough to avoid any sticking of the cleaning pigs, but also low enough to avoid any bypass of the fluid around the cleaning pig placed at the front. The travel velocity of the cleaning pigs may be from about 0.1 meter per second (m/s) to about 1 m/s, or from about 0.2 m/s to about 0.3 m/s, for example. Pressure may be monitored to ensure the cleaning pigs are not stuck. Once the smaller cleaning pigs (e.g., 2 inch in diameter) can move freely back and forth and that the flow is unobstructed, a larger in diameter pair of cleaning pigs may be launched with water or any displacing fluid in between. The next size in diameter for the cleaning pigs may be 2.5 inches in diameter, then 3 inches in diameter, then 3.5 inches in diameter, then 4 inches in diameter, and then 4.5 inches in diameter for a 5 inch in diameter furnace tubing, for example.

[0014] Once the at least one cleaning pig has been used for cleaning the inners walls of the coker furnace tubing, then a displacement fluid may be introduced inside the coker furnace tubing. The displacement fluid may, for example, push the cleaning pigs, their associated debris, and liquid out of the coker furnace tubing. The displacement fluid may be any fluid capable of displacing the debris and coking remaining inside the coker furnace tubing including diesel or nitrogen, for example. The displacement fluid comprising diesel, for example, may be displaced using at least one foaming pig or any pig capable of displacing any fluid. Therefore, in some embodiments, we may have one foaming pig pushing the displacement fluid that pushes the second cleaning pig that pushes a liquid in between the second and the first cleaning pig, and that liquid pushes the first cleaning pig, for example.

[0015] In embodiments, an inhibition composition may be introduced into the coker furnace tubing after the cleaning process described above. The term introducing includes any term for displacing a fluid including pumping, injecting, pushing, or any combination, for example. The inhibition composition, for example, may contact the inner wall of the coker furnace tubing to form a protective coating. Any suitable technique may be used with the inhibition composition, including a batch mixing method, a fill and soak method, or any combination thereof.

[0016] In embodiments of the batch mixing method, the inhibition composition is pushed in between two foaming pigs or any pigs capable of pushing the inhibition composition at a pressure and at a flow rate appropriate for the inhibition composition to contact the inner wall of the coker furnace tubing. The inner wall of the coker furnace tubing may be at temperatures ranging from about 4 C. to about 50 C., from about 5 C. to about 45 C., from about 10 C. to about 40 C., from about 15 C. to about 30 C., or from about 20 C. to about 30 C., for example. The travel velocity of the foaming pigs may be from about 0.1 m/s to about 1 m/s, or from about 0.2 m/s to about 0.3 m/s, for example.

[0017] In embodiments of the fill and soak method, the inhibition composition may be introduced into the coker furnace tubing and then allowed to soak within the coker furnace tubing for a soak period, for example, from about 1 minute to about 3 hours, from about 2 minutes to about 2 hours, from about 3 minutes to about 1 hour, from about 4 minutes to about 30 minutes, or from about 5 minutes to about 10 minutes. The inner wall of the coker furnace tubing period may be at temperatures ranging from about 4 C. to about 50 C., from about 5 C. to about 45 C., from about 10 C. to about 40 C., from about 15 C. to about 30 C., or from about 20 C. to about 30 C., for example.

[0018] The fill and soak method or the batch mixing method or a combination of the two may be employed, in accordance with example embodiments, to form a protective film on the inner wall of the coker furnace tubing from the inhibition composition. The protective film may have any suitable thickness, for example, from about 0.1 micrometer (m) to about 1 millimeter thick, 5 m to about 500 m thick, from about 10 m to about 250 m thick, from about 20 m to about 100 m thick, from about 25 m to about 75 m thick, from about 25 m to about 50 m thick, or from about 6.35 m to about 10 m thick.

[0019] In some embodiments, the inhibition composition may comprise at least one oil soluble or dispersible organo sulfonate compound with a divalent cation diluted in a hydrocarbon liquid such as diesel, for example. The oil soluble or dispersible organo sulfonate compound may be an overbased sulfonate with a pH from about 7.1 to about 12. The inhibition composition comprises an overbased sulfonate with a general formula RS(O).sub.2O.sup. with a pH greater than 7 with a divalent metal ion including Ca.sup.2+, Mg.sup.2+, Sr.sup.2+, Ba.sup.2+, Zn.sup.2+, for example. The inhibition composition may comprise the organo sulfonate compound diluted in a hydrocarbon liquid, such as diesel. The organo sulfonate compound may be diluted in the hydrocarbon liquid in any suitable amount, for example, from about a 3:7 volume ratio to about a 1:9 volume ratio or from about 10 % to about 30% by volume of organo sulfonate compound to about 70% to about 90% by volume hydrocarbon liquid. The inhibition composition may comprise a calcium, sodium, magnesium, or any combination thereof of overbased sulfonate diluted in a hydrocarbon liquid, such as diesel, for example, from about a 3:7 volume ratio to about a 1:9 volume ratio or from about 10% to about 30% by volume of overbased sulfonate to about 70% to about 90% by volume diesel, for example. The pH of the inhibition composition may be from 7.1 to about 12, from 7.5 to about 10, or from about 8 to about 9.5. In embodiments, the inhibition composition may comprise a calcium or magnesium salt of dodecyl benzene sulfonate, isopropyl naphthalene sulfonate, lignosulfonate, or any combination thereof. In other embodiments, the inhibition composition may comprise di, and/or tributyl thiophosphate ester, thiophosphate or sulfate ester of any other chain length than the mono, di, and/or tributyl thiophosphate ester, thiophenol, diethyl thiophosphate, mercapto-benzothiazole, 2-aminothiophenol, calcium octoate, and any combination thereof.

[0020] In embodiments, the inhibition composition further comprises additives such as dispersants, friction modifiers, anti-wear additives, anti-corrosion inhibitors, or any combination thereof, for example. The inhibition composition may comprise the additive in any range of concentrations, including from 0.0001 to 1 by volume of inhibition composition to 0.9 to 1 by volume of inhibition composition.

[0021] Dispersant additives may be used, for example, to control the state of aggregation of sludge. Dispersants may include amphiphilic molecules in which the lipophilic portion usually consists of polyolefinic chains (generally polyisobutene) with a molecular weight that varies between 700 and 3,000, while the polar group may be, in general, the derivative of a polyamine or of a polyol. The bond between these two parts of the final molecule may be obtained by means of different chemical reactions. Examples of dispersants include succinimides, succinic esters, alkylphenolamine (Mannich bases), and polymeric dispersants. Succinimides may be prepared in two stages: the first consists of functionalizing the chain of an alkyl oligomer (polyolefin, preferably polyisobutene) with maleic anhydride to produce a polyisobutylene succinanhydride (PIBSA). In the second stage, the PIBSA is converted into the final polyisobutylene succinimide (PIBSI) causing it to react with an N-amino-polyalkylamine (for example hexaethylene heptaamine, HEHA; tetraethylene penta-amine, TEPA, etc.). Succinic esters may be produced by esterifying a succinic derivative of a polyolefin (analogous to those used for succinimides) with mono- or poly-alcohols (for example pentaerythritol). Alkylphenolamines are polyisobutylenic phenols (or polyalkyl-substitutes) made to react with polyalkyleneamine by means of formaldehyde (through the Mannich reaction).

[0022] Friction modifiers may comprise very long amphiphilic organic molecules or metal-organic compounds (generally with a molybdenum base). The reduction of the friction coefficient of the surfaces may take place by means of the formation of an extremely smooth film of molecules over them.

[0023] The anti-wear additives are mainly used for reducing wear under boundary lubrication conditions. Under conditions of medium-to-high or extreme pressure, these additives react with the metal surfaces forming protective tribo-chemical layers. The anti-wear additive may comprise zinc dialkyl dithiophosphates, for example. They may be wear-prevention additives with a molybdenum base (dialkyl dithiophosphates, dithiocarbamates), organic compounds and metal detergents, sulphur-phosphorus compounds, and chlorinated paraffins. The anti-wear additive breaks down at the metal-metal interface at high temperature and it reacts with the contacting surfaces forming layers with a low friction coefficient.

[0024] The anti-corrosion additives act by creating a physical barrier on the metal surface. This barrier prevents corrosive agents from attacking the metal surface. The main types of anti-corrosive additives are etoxylate alcohols, long-chain carboxylic acids, phosphoric esters, amines, imidazoline, and thioderivatives, zinc dithiophosphates.

[0025] After introducing the inhibition composition, for example, to deposit a protective film on the coker furnace tubing, the feed of the coker furnace may be introduced into the coker furnace tubing. An oil soluble or dispersible organo sulfonate compound with a divalent cation may be introduced into the feed as a continuous treatment or intermittently right from the start of the feed introduction or after a delay. The delay for the introduction of the oil soluble or dispersible organo sulfonate compound into the feed may be from 1 minute to 80 days, from 5 minutes to 50 days, from 10 minutes to 25 days, from 30 minutes to 15 days, from 1 hour to 10 days, from 2 hours to 5 days, from 3 hours to 3 days, from 5 hours to 1 day, or any time in between. Further, the oil soluble or dispersible organo sulfonate compound in its basic form with a divalent cation may be introduced continuously at the same concentration, or alternatively, at different concentrations depending upon the fouling detected through measurements of the tube metal temperature (TMT) or other indirect measurement of internal coker furnace tubing fouling, for example. The concentrations of the oil soluble or dispersible organo sulfonate compound with a divalent cation being introduced in the coker feed may vary from about 1 ppm to about 1000 ppm, 25 ppm to about 500 ppm, from about 30 ppm to about 250 ppm, from about 50 ppm to about 100 ppm, or from about 30 to about 75 ppm, for example.

[0026] The suitable organo sulfonate compounds for introduction in the coker feed may include the organo sulfonate compounds described previously for use with the inhibition composition. The organo sulfonate compounds introduced with the coker feed may be the same or different than the organo sulfonate compound in the inhibition composition.

[0027] The coker feed may be any suitable hydrocarbon liquid including any residual oil from the vacuum distillation column, for example.

[0028] In other embodiments, coil tubing may be used alone or in combination with the fill and soak method or batch inhibition method to deliver the inhibition composition providing a passivation film after decoking or mechanical cleaning of the coker furnace tubing.

[0029] The benefits of the proposed methods and systems will be appreciated by the prolonged duration in between periodic shutdowns and cleanings which lead to reduced production losses. The systems and methods may comprise any of the various features disclosed herein, comprising one or more of the following statements.

[0030] Statement 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.

[0031] Statement 2. The method of Statement 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.

[0032] Statement 3. The method of Statement 1 or Statement 2, 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.

[0033] Statement 4. The method of any of Statements 1 to 3, 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.

[0034] Statement 5. The method of any of Statements 1 to 4, 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.

[0035] Statement 6. The method of any of Statements 1 to 5, wherein the first organo sulfate compound and the second organo sulfate compound each comprise a calcium or magnesium salt of dodecyl benzene sulfonate.

[0036] Statement 7. The method of any of Statements 1 to 6, wherein the first organo sulfate compound and the second organo sulfate compound each comprise isopropyl naphthalene sulfonate.

[0037] Statement 8. The method of any of Statements 1 to 7, wherein the first organo sulfate compound and the second organo sulfate compound each comprise lignosulfonate.

[0038] Statement 9. The method of any of Statements 1 to 8, 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.

[0039] Statement 10. The method of any of Statements 1 to 9, 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.

[0040] Statement 11. The method of any of Statements 1 to 10, wherein the inhibition composition has a pH from about 7.1 to about 9.5.

[0041] Statement 12. The method of any of Statements 1 to 11, wherein the inhibition composition has a pH from about 7.1 to about 8.0.

[0042] Statement 13. The method of any of Statements 1 to 12, wherein the second organo sulfate compound is introduced into the coker feed in a concentration of from about 25 ppm to about 250 ppm.

[0043] Statement 14. The method of any of Statements 1 to 13, wherein the second organo sulfate compound is introduced into the coker feed in a concentration of from about 30 to about 75 ppm.

[0044] Statement 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.

[0045] Statement 16. The method of Statement 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.

[0046] Statement 17. The method of Statement 15 or Statement 16, wherein the inhibition composition has a pH from about 7.1 to about 8.0.

[0047] Statement 18. The method of any of Statements 15-17, 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.

[0048] Statement 19. The method of any of Statements 15-18, 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.

[0049] Statement 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.

[0050] As it is impracticable to disclose every conceivable embodiment of the technology described herein, the figures, examples, and description provided herein disclose only a limited number of potential embodiments. One of ordinary skills in the art would appreciate that any number of potential variations or modifications may be made to the explicitly disclosed embodiments, and that such alternative embodiments remain within the scope of the broader technology. Accordingly, the scope should be limited only by the attached claims. Further, the compositions and methods are described in terms of comprising, containing, or including various components or steps, the compositions and methods may also consist essentially of or consist of the various components and steps. Moreover, the indefinite articles a or an, as used in the claims, are defined herein to mean one or more than one of the elements that it introduces. Certain technical details, known to those of ordinary skills in the art, may be omitted for brevity and to avoid cluttering the description of the novel aspects.

[0051] For further brevity, descriptions of similarly named components may be omitted if a description of that similarly named component exists elsewhere in the application. Accordingly, any component described with respect to a specific figure may be equivalent to one or more similarly named components shown or described in any other figure, and each component incorporates the description of every similarly named component provided in the application (unless explicitly noted otherwise). A description of any component is to be interpreted as an optional embodimentwhich may be implemented in addition to, in conjunction with, or in place of an embodiment of a similarlynamed component described for any other figure.

[0052] As used herein, adjective ordinal numbers (e.g., first, second, third, etc.) are used to distinguish between elements and do not create any particular ordering of the elements. As an example, a first element is distinct from a second element, but the first element may come after (or before) the second element in an ordering of elements. Accordingly, an order of elements exists only if ordered terminology is expressly provided (e.g., before, between, after, etc.) or a type of order is expressly provided (e.g., chronological, alphabetical, by size, etc.). Further, use of ordinal numbers does not preclude the existence of other elements. As an example, a table with a first leg and a second leg is any table with two or more legs (e.g., two legs, five legs, thirteen legs, etc.). A maximum quantity of elements exists only if express language is used to limit the upper bound (e.g., two or fewer, exactly five, nine to twenty, etc.). Similarly, singular use of an ordinal number does not imply the existence of another element. As an example, a first threshold may be the only threshold and therefore does not necessitate the existence of a second threshold.

[0053] As used herein, the word data may be used as an uncountable singular nounnot as the plural form of the singular noun datum. Accordingly, throughout the application, data is generally paired with a singular verb (e.g., the data is modified). However, data is not redefined to mean a single bit of digital information. Rather, as used herein, data means any one or more bit(s) of digital information that are grouped together (physically or logically). Further, data may be used as a plural noun if context provides the existence of multiple data (e.g., the two data are combined).

[0054] As used herein, the term operative connection (or operatively connected) means the direct or indirect connection between devices that allows for interaction in some way (e.g., via the exchange of information). For example, the phrase operatively connected may refer to a direct connection (e.g., a direct wired or wireless connection between devices) or an indirect connection (e.g., multiple wired and/or wireless connections between any number of other devices connecting the operatively connected devices).