Patent Publication Number: US-2016244677-A1

Title: Apparatuses and methods for fluid catalytic cracking with feedstock temperature control

Description:
TECHNICAL FIELD 
     The present disclosure generally relates to apparatuses and methods used in fluid catalytic cracking, and more particularly relates to apparatuses and methods for controlling feedstock temperatures for fluid catalytic cracking units. 
     BACKGROUND 
     It is desirable to produce fuels and other useful materials from renewable resources, such as natural oils. Natural organic matter, such as wood, agricultural waste, algae, and a wide variety of other feedstocks can be heated in the absence of oxygen to produce pyrolysis oil. The pyrolysis oil is produced from biomass in a pyrolysis reactor, so the pyrolysis oil is a renewable resource and a natural oil. Pyrolysis oil can be directly used as a fuel for some applications, such as certain boilers and furnaces, and it can also serve as a feedstock for the production of fuels in petroleum refineries. Pyrolysis oil has the potential to replace petroleum as the source of a significant portion of transportation fuels. However, pyrolysis oil is a complex, highly oxygenated organic liquid having properties that currently limit its utilization as a biofuel. For example, pyrolysis oil has high acidity and a low energy density attributable in large part to oxygenated hydrocarbons. These oxygenated hydrocarbons can undergo secondary reactions during storage or when heated to produce undesirable compounds, such as oligomers, polymers, and other compounds that cause plugging and block liquid transport operations. However, many pyrolysis oils become viscous if they become too cold, so the pyrolysis oils should be transported and stored within certain temperature ranges. 
     Fluid catalytic cracking (FCC) is primarily used to convert high boiling, high molecular weight hydrocarbons from petroleum into lower boiling, lower molecular weight compounds. The lower molecular weight compounds include gasoline, olefinic compounds, liquid petroleum gas (LPG), diesel fuel, kerosene, etc., where the feedstock and the operating conditions can be adjusted to shift yields to a desired product. During FCC unit operations, hydrocarbons are cracked with a cracking catalyst in a riser in the FCC unit, coke deposits on the cracking catalyst in the riser, and the coke is burned off in a regenerator to regenerate the cracking catalyst. The cracking catalyst is repeatedly cycled through the riser and regenerator while cracking hydrocarbons. Pyrolysis oil or other natural oils can be processed in FCC units to increase its value and utility for use as a fuel or as a raw material for other processes. However, the riser of the FCC unit is hot, so the pyrolysis oil may polymerize and “plug” when introduced to the riser. Pyrolysis oil is one example of a natural oil that can be processed in an FCC unit, but other natural oils or feedstocks that have temperature limitations can also be processed. 
     Accordingly, it is desirable to develop methods and apparatuses for introducing natural oils or other feedstocks to FCC units without plugging. In addition, it is desirable to develop methods and apparatuses for controlling the temperature of the feedstocks as they are introduced to the FCC unit. Furthermore, other desirable features and characteristics of the present embodiment will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawing and this background. 
     BRIEF SUMMARY 
     Apparatuses and methods are provided for fluid catalytic cracking. In an exemplary embodiment, a fluid catalytic cracking apparatus includes a riser with a first inlet. A first distributor pipe is coupled to the riser at the riser inlet. A heat transfer device is coupled to the first distributor pipe, where the heat transfer device includes a coolant outlet exterior to the riser, and wherein the heat transfer device is a counter current heat transfer device. 
     In another embodiment, a fluid catalytic cracking apparatus includes a riser with a first inlet. A first distributor pipe is coupled to the riser at the first inlet. A temperature control device is coupled to the first distributor pipe, where the temperature control device is configured to control a feedstock injection temperature. 
     A method of catalytically cracking hydrocarbons is also provided. The method includes fluidizing a cracking catalyst in a riser at cracking conditions, and injecting a first feedstock into the riser through a first distributor pipe at a feedstock injection temperature. The feedstock injection temperature is controlled to within a prescribed temperature range with a coolant, where the coolant flows through a temperature control device coupled to the first distributor pipe. The coolant exits the temperature control device exterior to the riser. The coolant flows through the heat transfer device in a counter current manner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein. 
         FIG. 1  is a cross-sectional view of a fluid catalytic cracking apparatus in accordance with exemplary embodiments; 
         FIG. 2  is a schematic diagram of a portion of a fluid catalytic cracking apparatus in accordance with exemplary embodiments; and 
         FIGS. 3-5  are side sectional views of various embodiments of a heat transfer device for a first distributor pipe of a fluid catalytic cracking apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description is merely exemplary in nature and is not intended to limit the application or uses of the embodiment described. Furthermore, there is no intention to be bound by any theory presented in the preceding technical field, background, brief summary, or the following detailed description. 
     Fluid catalytic cracking (FCC) apparatuses and methods for fluid catalytic cracking of hydrocarbons are provided. In accordance with various embodiments, a first feedstock is introduced into a riser of the FCC apparatus, and contacted with a cracking catalyst at cracking conditions. The first feedstock is added to the riser through a first distributor pipe, where the first feedstock is maintained within a prescribed temperature range until it is introduced into the riser. The hot riser tends to heat the first feedstock within the first distributor pipe, so a temperature control device is coupled to the first distributor pipe to control the temperature of the feedstock and prevent overheating. By “control”, as referred to herein, it is meant that the temperature of the feedstock is actively modified to maintain the temperature of the feedstock within a predetermined range. A coolant is used in the temperature control device, and the coolant is not introduced to the riser so the riser operations are not impacted by the additional coolant. 
     In accordance with an exemplary embodiment and referring to  FIG. 1 , an FCC apparatus  10  includes a riser  12  and a regenerator  40 . A first feedstock  14  is introduced to the riser  12  for cracking at a first inlet  16 , where the first feedstock  14  is a feedstock for the riser  12 . The first inlet  16  is defined in the riser  12 , such as an opening in a wall of the riser  12 . The first feedstock  14  includes a pyrolysis oil in an exemplary embodiment, but the first feedstock  14  may alternatively include a different natural oil, a petroleum oil, a chemical by-product, other materials, or a combination of materials. The first feedstock  14  may include about 20 weight percent to about 100 weight percent natural oil in an exemplary embodiment, or about 50 to about 100 weight percent natural oil, or about 80 to about 100 weight percent natural oil in alternate embodiments. The natural oil in the first feedstock  14  may be about 90 to about 100 weight percent pyrolysis oil in an exemplary embodiment, but other types of natural oil may be used in alternate embodiments. 
     Pyrolysis oil is produced by thermally decomposing organic matter in the absence of oxygen. In some embodiments, the pyrolysis oil is produced by rapid thermal pyrolysis, where the organic matter is rapidly heated to a reaction temperature of about 400° C. to about 900° C., maintained at the reaction temperature for about 0.5 to 2 seconds, and the vapors formed are then rapidly cooled to quench the pyrolysis reaction. However, other types of pyrolysis can be used in alternate embodiments. 
     Many pyrolysis oils are maintained within a pyrolysis oil flow temperature range for flowability reasons. Heavy organic or non-organic components in the pyrolysis oil tend to produce a high viscosity if the temperature falls below a pyrolysis oil flow temperature range (referred to herein as a “gelling temperature”). For example, the oil may solidify or “gel” if the oil temperature falls too low, but the oil will flow again if its temperature is raised to within the pyrolysis oil flow temperature range. Oxygenated organic compounds, olefins, aromatics, or other compounds in the pyrolysis oil tend to polymerize if the temperature rises above the pyrolysis oil flow temperature range. Therefore, if the temperature is too high, the oil polymerizes and forms a solid or gel that will not flow, even if the temperature is subsequently lowered to within the pyrolysis oil flow temperature range. In some cases, pyrolysis oil will polymerize and gel rapidly if heated above the pyrolysis oil flow temperature range, (referred to herein as a “polymerization temperature”) so plugging can occur when the oil is heated for short periods of time, such as about 5 minutes, 1 minute, 30 seconds, or 10 seconds in various embodiments. Furthermore, pyrolysis oil may begin to polymerize such that a pipe or conduit is gradually plugged as the oil flows through it. The pyrolysis oil flow temperature range is from about 30 degrees centigrade (° C.) to about 130° C., or from about 50 to about 100° C., or from about 50 to about 90° C. in various embodiments. As such, the first feedstock may be controlled to within an oil flow temperature range, which generally is from about the gelling temperature to about the polymerization temperature. The pyrolysis oil flow temperature range may vary from one type of pyrolysis oil to another, or between pyrolysis oils formed from different raw materials. When the first feedstock  14  is pyrolysis oil, the pyrolysis oil flow temperature range may be the prescribed temperature range for the first feedstock  14 . However, other prescribed temperature ranges may apply when the first feedstock  14  includes different materials. 
     Other natural oils also have natural oil flow temperature ranges. For example, a natural oil with a polymerizable functional group can polymerize if the temperature is raised too high, and many materials will solidify or plug if the temperature falls too low. Many natural oils include carbon-carbon double bonds on the fatty portion of the triglycerides, and these carbon-carbon double bonds may polymerize when the temperature exceeds a natural oil flow temperature range. For example, linoleic acid derived triglycerides, such as those found in sunflower oil, often include two carbon-carbon double bonds. Some natural oils or other materials may include conjugated carbon-carbon double bonds, where the double bonds are adjacent to each other, and these compounds may readily polymerize. For example, conjugated linoleic acid includes a conjugated double bonds, and pyrolysis oil includes compounds with conjugated double bonds as well. In embodiments with natural oil as the first feedstock  14 , the natural oil flow temperature range may be the prescribed temperature range for the first feedstock  14 . The prescribed temperature range is generally warm enough for the first feedstock  14  to be a flowable liquid, but cold enough to inhibit polymerization or other undesired chemical reactions. 
     The first feedstock  14  is contacted with a cracking catalyst  18  in the riser  12 . The cracking catalyst  18  can be a wide variety of cracking catalysts  18  as is known in the art. 
     Suitable cracking catalysts  18  for use herein include high activity crystalline alumina silicate and/or zeolite, which may be dispersed in a porous inorganic carrier material such as silica, alumina, zirconia, or clay. An exemplary embodiment of a cracking catalyst  18  includes crystalline zeolite as the primary active component, a matrix, a binder, and a filler. The zeolite ranges from about 10 to about 50 mass percent of the catalyst, and is a silica and alumina tetrahedral with a lattice structure that limits the size range of hydrocarbon molecules that can enter the lattice. In an embodiment, the matrix component includes amorphous alumina, and the binder and filler provide physical strength and integrity. For example, in a specific embodiment, silica sol or alumina sol are used as the binder and kaolin clay is used as the filler. Different cracking catalysts  18  may be used in alternate embodiments. 
     The first inlet  16  is positioned at a low portion of the riser  12 , so the first feedstock  14  travels upward through most of the length of the riser  12 . For example, the first inlet  16  may be from about 0.1 meters to about 10 meters from the bottom of the riser  12 , where the riser  12  may be about 5 to about 20 meters tall, but other dimensions are also possible. Hydrocarbons in the first feedstock  14  are vaporized, carried up through the riser  12  with the cracking catalyst  18 , and reacted (cracked) primarily within the riser  12 . The cracking catalyst  18  is fluidized in the riser  12  by a riser gas distributor  20 , where the riser gas distributor  20  may include one or more of steam, light hydrocarbons, nitrogen, or other gases. The first feedstock  14  is typically introduced into the riser  12  as a liquid, and the hydrocarbons in the first feedstock  14  are vaporized by heat from the hot cracking catalyst  18 . As the vaporized hydrocarbons and cracking catalyst  18  rise up through the riser  12 , the hydrocarbons contact with the cracking catalyst  18  and are cracked into smaller hydrocarbons. 
     In an exemplary embodiment, the riser  12  operates at a cracking temperature of from about 450° C. to about 600° C. The cracking temperature is measured in the vaporous stream at or near an outlet  22  of the riser  12 , where “near the outlet” is defined to mean within about 1 meter of the outlet  22 . Operating pressures in the riser  12  may be from about 100 kilo Pascals gauge (kPa) to about 250 kPa. The operating conditions may vary depending on several factors, including but not limited to, the composition of the first feedstock  14 , the cracking catalyst  18 , residence time in the riser  12 , catalyst loading in the riser  12 , the desired product, etc. The riser  12  is generally designed for a given feedstock and production rate, so the size, flow rate, and proportions can vary widely. In an exemplary embodiment, the riser  12  is designed for a first feedstock  14  residence time of from about 0.5 to about 10 seconds, but other residence times are also possible. 
     The FCC apparatus  10  may optionally include a second inlet  30  defined in the riser, with a second feedstock  32  introduced to the riser  12  at the second inlet  30 . The second inlet  30  may be positioned below the first inlet  16 , where the use of two different inlets allows for the separate introduction of two different feedstocks into the riser  12 . The second feedstock  32  may include a petroleum oil such as vacuum gas oil (VGO), hydrotreated VGO, atmospheric distillation column bottoms, demetallized oil, deasphalted oil, hydrocracker main column bottoms, combinations of the above, or other petroleum oils. Other suitable components for the second feedstock  32  include Fischer-Tropsch liquids derived from renewable or non-renewable feedstocks, triglycerides of vegetable or animal origin, natural oils, and the like. In some embodiments, the second feedstock  32  has an initial boiling point of about 300 degrees centigrade (° C.) or higher (at atmospheric pressure), and is a material that can vaporize and flow. In many embodiments, the second feedstock  32  is a mixture of different compounds, so it has a boiling range instead of a single boiling point, where the boiling range begins at the initial boiling point described above. In some embodiments, the hydrocarbons have an average molecular weight of about 200 to about 600 Daltons or higher. The first feedstock  14  may be heated to a temperature of from about 150° C. to about 450° C. (300° F. to 850° F.) before entry into the riser  12 . 
     The second inlet  30  may be below the first inlet  16 , and may be about 0.5 to about 9 meters below the first inlet  16  on the riser  12 . In alternate embodiments, the second inlet  30  is about  1  to about  8  meters below the first inlet  16 , or about 4 to about 6 meters below the first inlet  16 . In embodiments with the second inlet  30  below the first inlet  16 , the second feedstock  32  contacts the cracking catalyst  18  for a longer period of time than the first feedstock  14 . Also, the cracking reaction is endothermic, so the cracking catalyst  18  cools as the cracking catalyst  18  and the second feedstock  32  travel up the riser  12 . As such, the second feedstock  32  initially contacts the cracking catalyst  18  at a higher temperature than when the first feedstock  14  initially contacts the cracking catalyst  18 . The different positions of the first and second inlets  16 ,  30  allows for greater control of the cracking conditions for different feedstocks, so riser operations can be somewhat customized for different types of feedstock. In alternate embodiments, there is no second inlet  30 , or there may be more than two inlets. 
     In an exemplary embodiment, the first feedstock  14 , the second feedstock  32 , (if present,) and the cracking catalyst  18  travel up the riser  12  to a riser catalyst separator  24  fluidly coupled to the riser  12 . The vaporous hydrocarbons exit the riser catalyst separator  24  in a riser effluent  26  and the cracking catalyst  18  exits the riser catalyst separator  24  and collects in a riser catalyst collector  28 . Coke is deposited on the cracking catalyst  18  in the riser  12  such that the cracking catalyst  18  is at least partially coated with coke when falling into the riser catalyst collector  28 . The riser catalyst separator  24  may be one or more cyclones, impingement separators, other gas/solid separators, or combinations thereof. The cracking catalyst  18  is transferred to a regenerator  40  fluidly coupled to the riser catalyst collector  28 , and the riser effluent  26  flows to a fractionation zone (not illustrated) for further processing. 
     In an exemplary embodiment, the cracking catalyst  18  from the riser catalyst collector  28  is transferred to the regenerator  40  to oxidize the coke deposits formed on the cracking catalyst  18  in the riser  12 , which is often referred to as burning off the coke. Coke is burnt off the spent cracking catalyst  18  in a combustion zone  42  to produce a flue gas stream  44  and regenerated cracking catalyst  18 . The cracking catalyst  18  is separated from the flue gas stream  44  in a regenerator catalyst separator  46 , such as one or more cyclones, impingement separators, other gas/solid separators, or combinations thereof, and the cracking catalyst  18  is collected in a regenerator catalyst collector  48 . An oxygen supply gas  50  is coupled to the combustion zone  42  and carries the fluidized cracking catalyst  18  through the combustion zone  42 . The coke is burned off the cracking catalyst  18  by contact with the oxygen supply gas  50  at regeneration conditions. In an exemplary embodiment, air is used as the oxygen supply gas  50 , because air is readily available and provides sufficient O 2  for combustion, but other gases with a sufficient concentration of O 2  could also be used, such as purified O 2 . If air is used as the oxygen supply gas  50 , about 10 to about 15 kilograms (kg) of air is required per kg of coke burned off of the cracking catalyst  18 . Exemplary regeneration conditions include a temperature from about 500° C. to about 900° C. and a pressure of about 150 kPa to about 450 kPa. The superficial velocity of the oxygen supply gas  50  is typically less than about 2 meters per second, and the density within the combustion zone  42  is typically about 80 to about 400 kilograms per cubic meter. However, the regenerator  40  may be designed and sized based on the expected duty, so the regenerator  40  may be larger or smaller than as described above. 
     The hydrocarbon cracking reaction is endothermic, and heat is required to vaporize the hydrocarbons from the first feedstock  14  and the second feedstock  32 , if present. In some embodiments, the heat is primarily supplied by the cracking catalyst  18  that is transferred from the regenerator  40  to the riser  12 . As such, the FCC apparatus  10  may be about energy neutral, in that the energy used to vaporize and crack the hydrocarbons is primarily provided by the energy released from regenerating the cracking catalyst  18 . In an exemplary embodiment, about 70 percent of the heat used in the riser  12  is used to vaporize the first feedstock  14  and the second feedstock  32  (if present) with about 30 percent used to drive the endothermic cracking reaction, depending on the operating conditions and the composition of the first and second feedstocks  14 ,  32 . The combustion of coke is an exothermic reaction, so the cracking catalyst  18  is heated as it is regenerated. In an exemplary embodiment, the cracking catalyst  18  has a temperature of about 600° C. to about 760° C. when transferred from the regenerator  40  to the riser  12 . 
     Reference is made to the exemplary embodiment in  FIG. 2 , with continuing reference to  FIG. 1 . The first feedstock  14  is maintained within the prescribed temperature range prior to injection into the riser  12 , as mentioned above. The first feedstock  14  flows through a first distributor pipe  60  coupled to the riser  12  at the first inlet  16 . The first distributor pipe  60  may be introduced into the riser  12  through a port  58 , where the first distributor pipe  60  may be coupled to other pipes or conduits. The port  58  may be a blast nozzle or other port, and a packing gland or other seal may prevent leaks from the riser  12  through the port  58  when the first distributor pipe  60  (and any optional associated piping) is in place. The first feedstock  14  may be stored in a natural oil storage unit  98  fluidly coupled to the first distributor pipe  60 . The natural oil storage unit  98  is configured to provide a natural oil to the first inlet  16  as the first feedstock  14 , but other types of feedstocks are provided in alternate embodiments. 
     The riser  12  is vertical in many embodiments, and the first distributor pipe  60  may be coupled to the riser  12  at from about 30 degrees to about 60 degrees, such that the first distributor pipe  60  is angled upwards as it intersects the riser  12 . The port  58  may have a similar or identical angel. This angle may facilitate injecting the first feedstock  14  upwards into the riser  12  to aid in the generally upward flow within the riser  12 . The first distributor pipe  60  may also intersect the riser  12  at a right angle or at other angles in alternate embodiments. In an exemplary embodiment, a nozzle  34  is coupled to the end of the first distributor pipe  60  at the first inlet  16 , where the nozzle  34  is configured to atomize a liquid, such as the first feedstock  14 , and inject the atomized liquid into the riser  12 . The nozzle  34  may produce a cone-shaped spray, a fan-shaped spray, a mist, etc., when injecting the first feedstock  14  into the riser  12 . The nozzle  34  and/or the first distributor pipe  60  may be flush with the wall of the riser  12  so they do not extend into the flow path within the riser  12 . The flow of cracking catalyst  18  within the riser  12  may be abrasive, so the lifespan of the nozzle  34  and first distributor pipe  60  may be extended if they are not within the flow path of the cracking catalyst  18 . 
     The first feedstock  14  is injected into the riser  12  at a feedstock injection temperature. The first feedstock  14  remains liquid and flowable until it is atomized and injected into the riser  12  by the nozzle  34 , so the feedstock injection temperature may be below the boiling point or range of the first feedstock  14 . The riser  12  typically operates at high temperatures that may be well above the prescribed temperature range of the first feedstock  14 , so the riser  12  may have a tendency to heat the first feedstock  14  to above the prescribed temperature range prior to injection of the first feedstock  14 . The first distributor pipe  60  may be coupled to a heat transfer device  62  that can be used to control the temperature of the first feedstock  14  within the first distributor pipe  60 . The heat transfer device  62  can be used to maintain the temperature of the first feedstock  14  within the prescribed temperature range until it is injected into the riser  12 . The heat transfer device  62  may include a coolant inlet  64  and a coolant outlet  66  that are outside of the riser  12 , so coolant can flow through the heat transfer device  62  to control the feedstock injection temperature, without the coolant being injected into the riser  12 . The feedstock injection temperature may be controlled with a coolant that is injected into the riser  12 , but the addition of the coolant into the riser  12  may adversely impact the operation of the riser  12  or increase the cost of operation. For example, coolant injected into the riser  12  may reduce the quantity of feedstock that can be added, the injected coolant is lost, and the injected coolant may need to be separated from the riser effluent  26 . Therefore, a heat transfer device  62  with the coolant outlet  66  exterior to the riser  12  allows for recovery of the coolant and reduces dilution of the feedstock in the riser  12 . 
     The coolant used in the heat transfer device  62  may be stored in a coolant storage unit  68 , where the coolant storage unit  68  is configured to store the coolant in liquid form. The coolant storage unit  68  is fluidly coupled to the heat transfer device  62  such that coolant flows from the coolant storage unit  68  to the coolant inlet  64  of the heat transfer device  62 , and coolant flows from the coolant outlet  66  of the heat transfer device  62  back to the coolant storage unit  68 . 
     In some embodiments, a temperature control device  70  is used in conjunction with a first temperature sensing device  72  to control the feedstock injection temperature to within the prescribed temperature range. The first temperature sensing device  72  may be a thermocouple, a thermometer, or other device capable of measuring temperature. The first temperature sensing device  72  may be positioned within the first distributor pipe  60  to measure the temperature of the first feedstock  14  at or near the nozzle  34 . As such, the first temperature sensing device  72  may be within about 5 centimeters of the wall of the riser  12 , and within the first distributor pipe  60 . However, in other embodiments, the first temperature sensing device  72  may be within the flow path of the coolant, or within the natural oil storage unit  98  (not illustrated), at other locations, or there may be a plurality of first temperature sensing devices  72  at several different locations. The temperature control device  70  may adjust the flow rate of coolant to the heat transfer device  62  based on the readings of the temperature sensing element. The flow rate of the coolant can determine how much the first feedstock  14  is cooled, so changes to the flow rate can change the feedstock injection temperature. For example, the flow from a variable coolant pump  74  can be reduced or increased to control the feedstock injection temperature. In other embodiments, a valve (not illustrated) can control the flow of coolant. In other embodiments, the temperature of the coolant can be controlled, such as with a coolant heat exchanger  76 . Changes in the temperature of the coolant can also change the feedstock injection temperature, and can therefore be used for control purposes. 
     Many designs are available for the heat transfer device  62 . For example, the heat transfer device  62  may be as illustrated in  FIGS. 3 and 4 , with continuing reference to  FIG. 1 . The heat transfer device  62  illustrated in  FIGS. 3 and 4  includes an exterior sleeve  82  and an interior sleeve  84  with a counter current design, where the exterior sleeve  82  is inserted into the port  58 . The term “counter current” as used herein indicates the direction of flow of coolant along one surface of a process pipe is opposite to the direction of flow of process fluid (such as the first feedstock  14 ) along the opposite side of the process pipe. The first distributor pipe  60  is positioned within the interior sleeve  84  to define an interior annular space  88  between the first distributor pipe  60  and the interior sleeve  84 . The interior sleeve  84  is positioned within the exterior sleeve  82  to define an exterior annular space between the interior sleeve  84  and the exterior sleeve  82 . The space between the exterior sleeve  82  and the port  58  may include a packing gland or sealing device to prevent fluid flow, or leaks. The heat transfer device  62  includes a face plate  90  coupled to the first distributor pipe  60  and the exterior sleeve  82 , but the interior sleeve  84  is not directly coupled to the face plate  90 . An interior gap  85  is defined between the face plate  90  and the interior sleeve  84 , where coolant can flow through the interior gap  85 . The face plate  90  may be flush with the riser  12 , such as with a riser wall, to reduce abrasion from the cracking catalyst  18  flowing upward within the riser  12 . As such, the illustrated heat transfer device  62  is a counter current heat transfer device  62 . 
     In more general terms, the heat transfer device  62  includes a coolant inlet path  78  and a coolant outlet path  80  for coolant flow in and out of the heat transfer device  62 , respectively. The coolant inlet path  78  extends from the coolant inlet  64  to the face plate  90 , and the coolant outlet path  80  extends from the face plate  90  to the coolant outlet  66 . As such, the coolant inlet path  78  may be the exterior annular space  86 , and the coolant can change directions at the interior gap  85  so the coolant outlet path  80  is the interior annular space  88 . The coolant inlet path  78  could be the interior annular space  88  and the coolant outlet path  80  could be the exterior annular space  86  in another embodiment. 
     Another embodiment of the heat transfer device  162  is illustrated in  FIG. 5 , with continuing reference to  FIG. 1 . Components in  FIG. 5  that are similar to previously described components include the number “1” before the two digits used above, so the components in  FIG. 5  have different reference numbers for clarity but can be associated with similar components described above. New components in  FIG. 5  also begin with the number 1, but do not include a two digit reference number used above. The heat transfer device  162  includes an exterior sleeve  182  around the first distributor pipe  160 , where the exterior sleeve  182  and the first distributor pipe  160  are coupled to the face plate  190  that is flush with the riser  112 . The nozzle  134  is at the end of the first distributor pipe  160 . A baffle  158  is coupled to the exterior sleeve  182  and the first distributor pipe  160 , but the baffle  158  stops short of the face plate  190  to define the interior gap  185  between the baffle  158  and the face plate  190 . The coolant inlet path (not illustrate) is between the exterior sleeve  182  and the first distributor pipe  160  on one side of the baffle  158 , the coolant flows through the interior gap  185  between the end of the baffle  158  and the face plate  190 , and the coolant outlet path  180  is between the exterior sleeve  182  and the first distributor pipe  160  on the other side of the baffle  158 . Other embodiments of the heat transfer device  162  are also possible, as understood by those skilled in the art. The use of the heat transfer device  162  as described above allows for control of the feedstock injection temperature without the addition of coolant into the riser  12 . The controlled feedstock injection temperature may increase the number of raw materials that can be processed in an FCC apparatus  10  over FCC apparatuses without the heat transfer device  162 . 
     While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the application in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing one or more embodiments, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope, as set forth in the appended claims.