CN115301162A - Steam cracking furnace device for hydrocarbon - Google Patents

Abstract

The invention relates to a hydrocarbon steam cracking furnace device, which comprises a rectangular furnace box body, a furnace coil, a separator and a storage tank, wherein the coil main body of the furnace coil is in a transversely arranged spiral coil structure, and an electric heating belt for heating the furnace coil is arranged on the inner side wall of the furnace box body; the discharging pipe of furnace coil pipe is connected with the separator, and the separator bottom is provided with the holding vessel, and the holding vessel passes through the pipeline and is connected with the inlet pipe of furnace coil pipe, and the separator is used for separating the catalyst granule that adds in the furnace coil pipe and the coke granule that produces in the furnace coil pipe, adds solid catalyst granule in the holding vessel, and solid catalyst granule circulates in the pyrolysis furnace device. The invention utilizes the catalytic action of the catalyst to reduce the temperature required by the reaction, reduce coking and carbon deposit, and the solid catalyst particles carry out collision friction on the inner wall of the coil pipe in the process of circulating along with the airflow so as to separate the coke particles attached to the pipe wall.

Description

Steam cracking furnace device for hydrocarbon

Technical Field

The invention relates to the technical field of producing coal gas, coke, tar or the like by dry distillation of carbon-containing materials, in particular to a hydrocarbon steam cracking furnace device.

Background

Since biphenyl has high thermal stability and low vapor pressure, it has long been used alone or mixed with diphenyl ether as a heat carrier. The heat carrier is eutectic mixture of biphenyl and diphenyl ether in the mass ratio of 26.5 to 73.5 and may be used in temperature range of 12-400 deg.c, but the temperature range is 250-360 deg.c. Santal wax composed of biphenyl, terphenyl, etc. (13% by mass of biphenyl, 61% by mass of terphenyl) can effectively absorb radiation, and is suitable as a heat carrier for nuclear power plants. Terphenyl is just a byproduct in the preparation of biphenyl by benzene pyrolysis. Another major use of biphenyl is as a dye-directing agent in the printing and dyeing industry, and also as an impregnant for citrus packaging paper.

In 1926, the american dow chemical company, et al, began producing biphenyl by pyrolysis from benzene: initially benzene vapor was bubbled through a 750 ℃ molten lead bath, followed by a sodium chloride and calcium chloride bath, and then a resistive heater made of a metal with low catalytic activity (e.g., nichrome) was used.

At present, biphenyl is produced by a benzene high-temperature dehydrogenation method which is commonly adopted in the industry, specifically, the benzene high-temperature dehydrogenation method is to utilize a tubular cracking furnace to introduce benzene steam into a furnace tube of the cracking furnace to be heated to 700-800 ℃, and the biphenyl is prepared by mutually combining two benzene molecules without a hydrogen atom, and simultaneously hydrogen is generated. For example, the disclosure of the normal pressure pyrolysis system and the pyrolysis furnace disclosed in the patent application with publication number CN107641518A and the disclosure of the electrically heated ethylene pyrolysis furnace disclosed in the patent application with publication number CN113652246A, although the contents described in the above two patents are not directed to the production of biphenyl by the high temperature dehydrogenation of benzene, the specific apparatus described in the above two patents is also suitable for the reaction of benzene high temperature dehydrogenation to produce biphenyl. The cracking furnace equipment in the prior art has the following problems: the structural layout is not reasonable enough, and the structural stability of the furnace body, the maintenance of the furnace body, the specific shape and the arrangement mode of the furnace tube and the like all need to be optimized.

In addition, in the process for producing biphenyl by the high-temperature dehydrogenation method of benzene, three reactions are mainly carried out, wherein the reaction is a main reaction, namely a reaction for generating biphenyl; second, the second reaction of benzene, namely the reaction of generating terphenyl; thirdly, the deep carbonization of the benzene causes the coking of the inner wall of the furnace tube. In addition to the main reaction, other reactions are undesired side reactions, in particular coking of benzene by carbonization. The coke accumulation on the inner wall of the furnace tube can cause the need of higher furnace temperature and uneven distribution of the temperature of the furnace tube, influence the reaction effect, and need to stop the cracking furnace after running for a period of time to burn off coke deposits. This may result in a reduction in production efficiency. Therefore, the coke deposition is avoided in the reaction, and the coking or on-line decoking (decoking) is reduced, so that the continuous operation time of the equipment is prolonged, and the frequency of stopping the decoking (decoking) is reduced.

The method for avoiding the undesired side reaction is to avoid local overheating in the reaction and to prevent the material from staying too long in a high-temperature area to generate carbon and a large amount of polybiphenyl, and the actual production process is usually diluted by adopting high material flow rate and adding superheated steam or high-temperature flue gas. When there is a catalyst (MgO, thO) ₂ And CoO, etc.), higher yields of biphenyl can be obtained at lower temperatures.

In the prior art, a typical decoking (decoking) process involves flowing a mixture of steam and air through a designated zone. The mixture is subjected to one or more of desorption (chemical and/or physical), ablation (e.g., including one or more of abrasion, corrosion, fragmentation, exfoliation, gasification, and vaporization), and reaction (e.g., including one or more of combustion, partial combustion, and hydrogen transfer), etc. to remove coke; or a specific structure is arranged in the furnace tube to induce coke particles to be attached to the structure, so that the coke particles are prevented from being attached to the interior of the furnace tube.

The problems of the prior art, such as the coke removal of the mixture through desorption, the need for equipment shutdown and the influence on the generation efficiency; the furnace tube is provided with an internal structure to induce coking, and because the corresponding structure is in contact with the inside of the furnace tube, the contact part is easy to form deposition of coke, but is not beneficial to decoking.

Disclosure of Invention

The invention aims to provide a steam cracking furnace device of hydrocarbon substances, which is convenient for on-line decoking.

In order to solve the problems, the technical scheme adopted by the invention is as follows:

a hydrocarbon steam cracking furnace device comprises a rectangular furnace box body, a furnace coil, a separator and a storage tank, wherein an opening is formed in one side of the furnace box body, an openable furnace door is arranged on the furnace box body, the coil main body of the furnace coil is of a spiral coil structure which is transversely arranged, and an electric heating belt for heating the furnace coil is arranged on the inner side wall of the furnace box body; the discharging pipe connection separator of stove coil pipe, the separator bottom is provided with the holding vessel, the holding vessel passes through the pipeline and is connected with the inlet pipe of stove coil pipe, the separator is used for the separation to add the coke granule of the intraductal catalyst granule of stove coil and the intraductal production of stove coil, still be provided with the material on the holding vessel and add mouth and bin outlet, add in the holding vessel and have solid catalyst granule, solid catalyst granule circulates in the pyrolysis furnace device.

In one embodiment of the present invention, a pump for pressurizing is provided on a pipe between the storage tank and the feed pipe.

In one embodiment of the present invention, a coke burner is further disposed between the separator and the storage tank, and the coke burner is configured to perform a coke burning process on coke particles in the solid particles separated by the separator.

As an embodiment of the invention, the feeding pipe and the discharging pipe of the furnace coil pipe are both connected with the same heat exchanger, and the material in the feeding pipe and the material in the discharging pipe exchange heat.

In one embodiment of the present invention, a bottom plate and/or a top plate of the oven box body is provided with a plurality of oven supporting bodies, one end of each oven supporting body is in contact with the oven coil pipe, the other end of each oven supporting body is connected with an ultrasonic transducer, and the plurality of ultrasonic transducers are respectively connected with an ultrasonic generator.

As an embodiment of the present invention, a furnace coil pipe support frame is disposed on an inner bottom surface of the furnace box body, the furnace coil pipe is disposed on the furnace coil pipe support frame, the furnace coil pipe support frame includes two main support pipes disposed in parallel, the main support pipes are disposed along an extending direction of the furnace coil pipe, a first end of each main support pipe is connected to a side plate of the furnace box body, and a second end of each main support pipe is connected to a bottom plate of the furnace box body.

As an embodiment of the invention, the second end of the main support pipe is vertically and fixedly provided with a baffle pipe, and an inclined support pipe is arranged between the baffle pipe and the second end of the main support pipe.

In one embodiment of the present invention, each of the side plates, the top plate and the bottom plate of the furnace casing includes an outermost steel plate, a steel-structured support frame fixedly disposed inside the steel plate, and a heat insulating layer, and the inside of the bottom plate is provided with a plurality of furnace supports along the main support tubes, and the main support tubes are supported by the furnace supports.

As an embodiment of the present invention, a plurality of heating belt connection holes are formed on two side walls of the furnace box body, the heating belt connection holes are used for installing an extraction rod of an electric heating belt, and a bakelite seat is arranged between the extraction rod and the heating belt connection holes.

As an embodiment of the invention, a plurality of box supporting legs are arranged at the bottom of the furnace box body, concrete for the ground foundation where the cracking furnace device is located is poured, wherein the upper surface of the bottom plate of each box supporting leg is flush with the upper surface of the concrete foundation, at least two embedded parts are fixedly arranged at the bottoms of the bottom plates of the box supporting legs, and the embedded parts are embedded in the concrete foundation.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

the cracking furnace provided by the invention is suitable for high-temperature collision cracking reaction of hydrocarbons, such as biphenyl generated by benzene steam cracking. Through add separator and holding vessel in the device, further utilize solid catalyst granule to add and circulate in the furnace coil pipe of pyrolysis furnace, the required temperature of reaction can be reduced to the catalytic action that can utilize the catalyst on the one hand, the efficiency of reaction is improved, the situation of reaction carbomorphism can further be reduced in the cooling, reduce coking and carbon deposit, on the other hand, solid catalyst granule is carrying out collision friction to the coil pipe inner wall along with the in-process that the air current circulates, make the coke granule attached to on the pipe wall break away from, flow along with the material, the coking and the carbon deposit of pipe wall have further been reduced, realize on-line decoking and decoking through above-mentioned mode, the temperature of each position in the assurance boiler tube is even controllable. Due to the realization of on-line decoking, the operation time of the cracking furnace can be prolonged, the frequency of stopping for decoking is reduced, and the production cost can be reduced.

Drawings

FIG. 1 is a schematic view of a first embodiment of a cracking furnace apparatus.

FIG. 2 is a schematic view of a second embodiment of the cracking furnace apparatus.

FIG. 3 is a schematic view of a third embodiment of the cracking furnace apparatus.

FIG. 4 is a schematic view of the internal structure of the cracking furnace of the present invention.

Fig. 5 is a partially enlarged view of a portion a in fig. 4.

FIG. 6 is a side view, half-section, schematic view of the furnace shell.

Fig. 7 is a structural schematic diagram of a furnace door of the furnace box body.

FIG. 8 is a schematic view of the overall side view and half-section structure of the cracking furnace.

FIG. 9 is a schematic view of the top view of the inside of the cracking furnace.

Fig. 10 is a structural schematic diagram of a locking mechanism of the oven door.

Fig. 11 is a furnace box body axis view.

Fig. 12 is a schematic view of a support frame structure of a side plate of the oven case.

FIG. 13 is a schematic view of a basic embedment structure of the cracking furnace.

FIG. 14 is a schematic side view of a cracking furnace.

FIG. 15 is a schematic top view of the furnace.

Wherein: the device comprises a furnace box body 1, a furnace coil 2, a furnace feed pipe 2-1, a furnace discharge pipe 2-2, a coil main body 2-3, a furnace door 3, a furnace coil support frame 4, a main support pipe 5, a baffle pipe 6, an inclined support pipe 7, a furnace support body 8, a fixed buckle 9, a box support foot 10, an electric heating belt 11, a connecting arm 12, a rotating shaft 13, a connecting lug plate 14, an ultrasonic transducer 15, a vertical support rod 16, a transverse support rod 17, a pressing plate 18, a hand wheel 19, a locking screw 20, a heat preservation and insulation layer 21, a separator 22, a storage tank 23, a pump 24, a first valve 25, a second valve 26, a coke burner 27, a heat exchanger 28, a lifting lug 29, a support frame 30, a connecting piece 31, a fixing bolt 32, a heating belt connecting hole 33, a temperature measuring hole 34, an embedded part 35 and a concrete foundation 100.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail and fully with reference to the following embodiments.

The present embodiment will be described in detail by taking the example of the production of biphenyl by benzene cracking as an example of a hydrocarbon steam cracking furnace apparatus shown in fig. 1. The device can also be applied to the cracking reaction of other hydrocarbon substances under different process conditions.

The cracking furnace device comprises a rectangular furnace box body 1, a furnace coil pipe 2, a separator 22 and a storage tank 23, wherein one side of the furnace box body 1 (the detailed structure of the furnace box body 1 is shown in figures 4-7) is opened and is provided with an openable furnace door 3, a coil pipe main body 2-3 of the furnace coil pipe 2 is in a transversely arranged spiral coil pipe structure, and an electric heating belt 11 for heating the furnace coil pipe 2 is arranged on the inner side wall of the furnace box body 1; the heating strips 11 are used for the radiant heating of the furnace coil 2. The radiant heating section of the furnace box body 1 is divided into 3 sections, the temperature of the first section to the third section is sequentially increased, for example, the first section is 720-750 ℃, the second section is 750-780 ℃, and the third section is 780-800 ℃. The pressure in the furnace coil 2 is preferably 0.25Mpa.

The discharge pipe 2-2 of the furnace coil 2 is connected with a separator 22, the separator 22 can be a cyclone separator, a storage tank 23 is arranged at the bottom of the separator 22, and a check valve (not shown) can be arranged between the storage tank 23 and the separator 22. The storage tank 23 is connected to the feeding pipe 2-1 of the furnace coil 2 through a pipeline, the separator 22 is used for separating catalyst particles added into the furnace coil 2 and coke particles generated in the furnace coil 2, solid particles (including catalyst particles and coke particles) are settled in the separator 22 and flow out from the bottom of the separator, and gas materials flow out from the top of the separator 22. The solid particles flow further into said storage tank 23.

Still be provided with material on the holding vessel 23 and add mouth and bin outlet, add in the holding vessel 23 and have solid catalyst particle, solid catalyst particle circulates in the pyrolysis furnace device. The solid catalyst particles are preferably ThO ₂ ，ThO ₂ Has higher fire resistance, mohs hardness of 6.5, preferably ThO ₂ Spherical solid particles of about 100 μm, for example 80-120 μm, are prepared. By utilizing the friction and collision action of the solid catalyst particles on the inner wall of the furnace coil 2, the coke formed on the inner wall of the furnace coil 2 can be separated from the tube wall by the friction and collision action of the solid catalyst particles, so that the problem of coking on the inner wall of the furnace coil 2 is greatly relieved. Because a certain amount of ThO is added into the furnace coil 2 along with the benzene vapor ₂ The particles being as catalysts, thO ₂ The concentration of the particles is 1-5% of the weight of the reaction system, and the reaction temperature can be properly reduced under the action of the catalyst, for example, the temperature of the first section is 670-700 ℃, the temperature of the second section is 700-730 ℃, and the temperature of the third section is 730-750 ℃. Or, the radiation heating section in the furnace box body 1 is divided into 4 sections, and the temperature of the 4 sections can adopt: the temperature of the first section is 650-670 ℃, the temperature of the second section is 670-700 ℃, the temperature of the third section is 700-730 ℃, and the temperature of the fourth section is 730-750 ℃.

Wherein, the solid particles of catalyst circulate in the furnace coil 2 along with the flow direction of the material, the separator 22 can separate the solid particles of catalyst flowing out along with the material in the discharging pipe 2-2 from the gaseous material, and the solid particles of catalyst descend into the storage tank 23 in the separator 22. The storage tank 23 and the pipeline between the feeding pipes 2-1 are provided with a pump 24 for pressurization, high-temperature steam can be introduced into the storage tank 23 or the pipeline at the downstream of the storage tank, the catalyst solid particles are repeatedly conveyed into the feeding pipes 2-1 through the pressurization of the pump 24, the temperature and the pressure of the high-temperature steam are slightly higher than those in the feeding pipes 2-1, and the high-temperature steam can be benzene steam or water steam.

Referring to the second embodiment shown in fig. 2, since the coke generated during the reaction flows out of the discharging pipe 2-2 together with the reaction material and the catalyst and is separated from the catalyst under the action of the separator 22, in order to avoid the coke particles generated by the reaction from being circulated into the furnace coil 2, a coke burner 27 is further disposed between the separator 22 and the storage tank 23, the coke burner 27 is used for burning the coke particles in the solid particles separated by the separator 22, and the coke particles generate CO and CO at high temperature (e.g. 800-1000 ℃) ₂ And simultaneously, the carbon attached to the solid catalyst particles is also cleaned, so that the solid catalyst particles are regenerated to a certain extent. A check valve or an isolation valve is arranged between the coke burning device 27 and the separator 22, the coke burning device is supplied with air and a certain amount of air when working, and an exhaust pipe is arranged to generate CO and CO ₂ And (4) discharging. The make-up and vent lines are not shown.

Referring to the third embodiment shown in fig. 3, the feeding pipe 2-1 and the discharging pipe 2-2 of the furnace coil 2 are both connected with the same heat exchanger 28, and the material in the feeding pipe 2-1 exchanges heat with the material in the discharging pipe 2-2. The temperature of the final-stage material of the cracking furnace is about 750 ℃, the material needs to be cooled after being discharged from the discharge pipe 2-2, and the benzene vapor at the feeding end is heated or preheated by using the waste heat of the discharge pipe 2-2, so that the energy can be saved.

Fig. 4 to 15 show a specific structure of a preferred oven case 1. The whole furnace box body 1 is of a cuboid structure and is horizontally arranged, one of the two smaller side surfaces is open, and the furnace door 3 is arranged at the open.

Referring to fig. 4, 7, 8 and 9, two connecting ear plates 14 are fixedly arranged on the left side of the open end of the oven body 1, a rotating shaft 13 is arranged between the two connecting ear plates 14, and a bearing is arranged between the rotating shaft 13 and the connecting ear plates 14. The oven door 3 is fixedly connected with a rotating shaft 13 through two connecting arms 12, so that the oven door 3 can rotate along with the rotating shaft 13. Two locking screws 20 are arranged on the right side of the open end of the furnace box body 1, and the locking screws 20 are hinged on the furnace box body 1, so that the locking screws 20 can swing left and right. The pressing plate 18 is sleeved on the locking screw rod 20, the hand wheel 19 is further arranged on the locking screw rod 20, the hand wheel 19 is in threaded fit with the locking screw rod 20, the hand wheel 19 is rotated to push the pressing plate 18 to press the free end on the right side of the furnace door 3 tightly, the furnace door 3 is locked, the hand wheel 19 is rotated towards the other direction to loosen the pressing plate 18, and the locking screw rod 20 is swung to open the furnace door 3. The furnace door is arranged through the structure, so that the furnace door is simple to open and close and convenient to overhaul.

As shown in fig. 4, which is a schematic view of the internal structure of the cracking furnace, a furnace coil support frame 4 is arranged on the bottom surface of the interior of the furnace box body 1, and the furnace coil 2 is arranged on the furnace coil support frame 4. The furnace coil supporting frame 4 comprises two main supporting tubes 5 which are arranged in parallel, the main supporting tubes 5 are arranged along the extending direction of the furnace coil 2, the first ends of the main supporting tubes 5 are connected with the side plates of the furnace box body 1, the second ends of the main supporting tubes 5 are connected with the bottom plate of the furnace box body 1, and the second ends of the main supporting tubes 5 are one side of the furnace door 3; as shown in fig. 4 and 5, the two sides of the second end of the main support pipe 5 are provided with fixing bolts 32, the fixing bolts 32 are fixedly connected with the bottom plate of the furnace box body 1, the two ends of the fixing buckle plate 9 are connected to the fixed bolts 32, and are locked by nuts, so that the fixing buckle plate 9 is pressed on the second end of the main support pipe 5, the structure of the furnace coil support frame 4 is firmer and more stable, and the main support pipe 5 is prevented from warping and deforming.

The second end vertical fixation of main tributary stay tube 5 is provided with keeps off pipe 6, keep off and be provided with bearing diagonal pipe 7 between the second end of pipe 6 and main tributary stay tube 5, bearing diagonal pipe 7 is the arc structure for support keeps off pipe 6, avoids keeping off pipe 6 and receive furnace coil 2 extrusion slope deformation.

In the embodiment, the coil main body 2-3 of the furnace coil 2 is a spiral coil structure which is transversely arranged and is similar to a spring in shape, so that the coil main body 2-3 can continuously extend, the curvatures of all positions are the same and can keep smaller curvatures, and compared with a snake-shaped coil, the coil has no inflection point, so that the material flows smoothly, and the defect of easy carbon deposition at the inflection point is avoided.

Because the coil main body 2-3 is similar to a spring, the coil main body can be transversely stretched and contracted under the influence of expansion with heat and contraction with cold in the parking state and the reaction process, so that the damage of stress to the furnace tube is reduced.

The feeding pipe 2-1 and the discharging pipe 2-2 of the furnace coil 2 are both positioned on one side far away from the furnace door 3, the feeding pipe 2-1 vertically enters the furnace body 1 from the top plate and then is connected with the coil main body 2-3, the furnace coil 2 at the tail end of the coil main body 2-3 is turned back and forms a cylinder body extending from the coil main body 2-3 to the feeding pipe 2-1, the discharging pipe 2-2 is vertically extended from the top plate of the furnace body 1, and the feeding pipe 2-1 and the discharging pipe 2-2 are positioned on the same side of the furnace body 1, so that the heat exchanger 28 can be conveniently connected.

Since the feed pipe 2-1 and the discharge pipe 2-2 pass through the top plate of the furnace chamber body 1, the feed pipe 2-1 and the discharge pipe 2-2 are constrained to each other with the top plate of the furnace chamber body 1, so that the furnace coil 2 is fixed at one side of the feed pipe 2-1 (and the discharge pipe 2-2). And the other side of the furnace coil 2 is not connected with the furnace box body 1 and the furnace coil support frame 4, namely, the other side (the side close to the furnace door 3) of the furnace coil 2 is a free end, and along with the change of temperature, the free end moves for a certain distance along the main support pipe 5 of the furnace coil support frame 4 during the integral expansion and contraction period of the coil main body 2-3 of the furnace coil 2. The two main supporting pipes 5 are arranged in parallel, a concave structure is formed between the two main supporting pipes and the bottom plate of the furnace box body 1, the spiral coil main body 2-3 which is shaped like a spring can be placed on the two main supporting pipes 5, the spring-shaped (cylindrical) coil main body 2-3 is supported by the two main supporting pipes 5, the lowest end of the bottom of the coil main body is not in contact with the bottom plate of the furnace box body 1, and the coil main body 2-3 is not fixedly connected with the main supporting pipes 5, so that the coil main body 2-3 can freely deform after being expanded with heat and contracted with cold.

In this embodiment, it is preferable that the furnace casing has a peripheral length of about 5000mm, a height and a width of 2500-2800mm, an outer diameter of a cylinder formed by the coil bodies 2-3 is about 1400mm, and an outer diameter of a tube body of the furnace coil 2 is about 90mm. The furnace tube is made of HK4M alloy.

As shown in fig. 11 and 12, the side plates, the top plate and the bottom plate of the furnace box 1 each include an outermost steel plate, a steel-structured support frame fixedly disposed on the inner side of the steel plate, and a heat-insulating layer 21, the inner side of the bottom plate is provided with a plurality of furnace supports 8 along the main support pipes 5, and the main support pipes 5 are supported by the furnace supports 8. The supporting frame comprises a rectangular supporting frame 30 and a transverse supporting rod 17, wherein the array is arranged on vertical supporting rods 16 and transverse supporting rods 17 arranged between the vertical supporting rods 16 in the supporting frame 30, connecting pieces 31 are arranged at the corners of the supporting frame 30 and the joints of the vertical supporting rods 16 and the transverse supporting rods 17, and the connecting pieces 31 play a role in fixed connection and strengthening fixation. The vertical supporting rod 16 and the transverse supporting rod 17 are made of angle steel or channel steel, the connecting points of the angle steel or channel steel can be welded, and the connecting piece 31 plays a role in reinforcing during welding. The supporting frame forms a framework structure of a side plate, a top plate and a bottom plate of the furnace box body 1, the inner sides of the side plate, the top plate and the bottom plate are provided with a heat insulation layer 21, the thickness of the heat insulation layer 21 is about 350mm, a high-temperature-resistant heat insulation cotton material is adopted, and the supporting frame has the function of fixing the heat insulation layer 21. The heat insulation layer 21 is used for insulating the interior of the furnace body, preventing heat loss and avoiding the serious influence of the high temperature in the cracking furnace on the surrounding environment.

As shown in fig. 4 and 14, the radiation heating section of the furnace body 1 is divided into 3 sections or 4 sections, and each section of the radiation heating section is heated by a plurality of electric heating bands 11. The electric heating belt 11 is arranged on the heat preservation and insulation layer 21. A plurality of heating band connecting holes 33 are formed in two side walls of the furnace box body 1, the heating band connecting holes 33 are used for setting a leading-out rod of a heating band, the heating band is connected with a power supply, and a bakelite seat is arranged between the leading-out rod and the heating band connecting holes 33. As shown in fig. 15, a plurality of temperature measuring holes 34 are provided on the top plate of the furnace box body 1, and are used for providing temperature sensors in the temperature measuring holes 34 and detecting and controlling the temperature of each radiation section.

As shown in fig. 4 and 13, a plurality of box supporting legs 10 are arranged at the bottom of the furnace box 1, concrete for a ground foundation where the cracking furnace device is located is poured, wherein the upper surface of the bottom plate of each box supporting leg 10 is flush with the upper surface of the concrete foundation 100, at least two embedded parts 35 are fixedly arranged at the bottoms of the bottom plates of the box supporting legs 10, the embedded parts 35 are embedded in the concrete foundation, the embedded parts 35 are L-shaped or J-shaped, and the height H of the embedded parts is 250mm. The concrete foundation 100 can not only keep the ground firm and flat for placing the cracking furnace, but also avoid the inclination of the furnace body caused by the collapse of the ground. Meanwhile, the furnace body is firmly connected with the concrete foundation 100 through the embedded parts 35 at the bottom of the box body supporting legs 10, so that the furnace body is prevented from displacing in the operation process.

Based on the structure of the furnace body of the cracking furnace and the on-line decoking effect of the device is further improved, a plurality of furnace supporting bodies 8 are arranged on the bottom plate and/or the top plate of the furnace box body 1, one end of each furnace supporting body 8 is in contact with the furnace coil 2, the other end of each furnace supporting body is connected with an ultrasonic transducer 15, and the ultrasonic transducers 15 are respectively connected with an ultrasonic generator (not shown). Furnace tubes of adjacent tamping (rings) of the coil main bodies 2-3 of the furnace coil 2 are in close contact, so that ultrasonic conduction is facilitated.

In this embodiment, because be provided with a plurality of furnace internal support 8 on the bottom plate of furnace box 1, main tributary stay tube 5 passes through furnace internal support 8 supports, and main tributary stay tube 5 is used for supporting whole furnace coil 2, therefore the ultrasonic wave transmits between the solid, transmits for furnace coil 2 through main tributary stay tube 5 by furnace internal support 8, makes furnace coil 2 receive ultrasonic impact and vibrates, impels the coke particle that the reaction generated to break away from the pipe wall. Preferably, a plurality of furnace supports 8 are provided on the ceiling of the furnace casing 1, the furnace supports 8 on the top are in direct contact with the furnace coil 2, and the ultrasonic transducers 15 are provided outside the furnace supports 8 on the top.

The frequency of the ultrasonic transducer 15 is preferably 30-50kHz, the ultrasonic transducer 15 transmits ultrasonic vibration to the furnace coil 2 through the furnace supporting body 8, so that the furnace coil 2 is continuously subjected to ultrasonic vibration in the reaction process, further the hash of coke is promoted, and coke particles are difficult to attach or detach from the inner wall of the furnace coil 2. By the combined action of the ultrasonic transducer 15 and the catalyst solid particles, the continuous working time of the cracking furnace can be greatly prolonged, and the frequency of stopping and decoking can be reduced in a longer period. The support body 8 in the stove can adopt solid round steel, and its top sets up connecting block and stove coil pipe 2 in close contact with, and solid construction can avoid the decay of ultrasonic wave to a certain extent, has better conduction effect to the ultrasonic wave. Because the working temperature of the ultrasonic transducer 15 cannot be too high (not more than 85 ℃), the ultrasonic transducer 15 needs to be arranged outside the furnace body of the cracking furnace to avoid the influence of high temperature on the performance of the cracking furnace, and the ultrasonic transducer 15 arranged outside conducts ultrasonic waves to the furnace coil 2 through the furnace supporting body 8.

The furnace coil 2 is continuously vibrated in the process of material reaction by adopting the ultrasonic transducer 15, the adhesion and deposition of coke particles are avoided, the formation of coking on the inner wall of the furnace coil 2 can be effectively reduced, and the ultrasonic transducer 15 is arranged outside the furnace coil, so the structure is easier to implement, the inner structure of the furnace coil is not influenced, the operability and the exertion space are larger, and the start-stop of the ultrasonic transducer 15 and the power of the ultrasonic transducer can be timely selected and adjusted in the operation process.

As a modified embodiment, reference may be made to the structural schematic shown in fig. 1 to 4, in the middle of the furnace coil 2, for example, between the first radiant heating section and the second radiant heating section, and/or between the second radiant heating section and the third radiant heating section, and/or between the third radiant heating section and the fourth radiant heating section, at which point a pressure-compensating pipe (not shown) is connected to open, through which preheated benzene vapor or water vapor is introduced, the pressure and temperature of the pressure-compensating pipe being slightly higher than the pressure and temperature of the material in the connection with the furnace coil 2. A temperature sensor can be arranged at the pressure compensating pipe to monitor the temperature in the furnace coil pipe at the position in real time. The problems of slow flow rate and overlong reaction time caused by the attenuation of the pressure of the material in the furnace coil pipe 2 can be solved through the pressure compensation of the pressure compensation pipe. Between two adjacent radiation sections, a short plate can be arranged to form a partition, so that mutual interference between the adjacent radiation sections is reduced, and the temperature is ensured to be controllable.

Claims (10)

1. A hydrocarbon steam cracking furnace assembly, characterized by: the furnace coil pipe heating device comprises a rectangular furnace box body (1), a furnace coil pipe (2), a separator (22) and a storage tank (23), wherein an openable furnace door (3) is arranged at one side of the furnace box body (1), a coil pipe main body (2-3) of the furnace coil pipe (2) is of a spiral coil pipe structure which is transversely arranged, and an electric heating belt (11) for heating the furnace coil pipe (2) is arranged on the inner side wall of the furnace box body (1); discharging pipe (2-2) connection separator (22) of stove coil pipe (2), separator (22) bottom is provided with holding vessel (23), holding vessel (23) are connected with inlet pipe (2-1) of stove coil pipe (2) through the pipeline, separator (22) are used for the separation to add the coke particle of catalyst granule and stove coil pipe (2) production in the stove coil pipe (2), still be provided with material interpolation mouth and bin outlet on holding vessel (23), add solid catalyst granule in holding vessel (23), solid catalyst granule is at the pyrolysis furnace device mesocycle.

2. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: a pump (24) for pressurizing is arranged on a pipeline between the storage tank (23) and the feeding pipe (2-1).

3. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: a coke burning device (27) is further arranged between the separator (22) and the storage tank (23), and the coke burning device (27) is used for burning coke particles in the solid particles separated by the separator (22).

4. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: the feeding pipe (2-1) and the discharging pipe (2-2) of the furnace coil pipe (2) are both connected with the same heat exchanger (28), and materials in the feeding pipe (2-1) and materials in the discharging pipe (2-2) exchange heat.

5. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: a plurality of furnace supporting bodies (8) are arranged on a bottom plate and/or a top plate of the furnace box body (1), one end of each furnace supporting body (8) is in contact with the furnace coil pipe (2), the other end of each furnace supporting body is connected with an ultrasonic transducer (15), and the ultrasonic transducers (15) are respectively connected with an ultrasonic generator.

6. A hydrocarbon steam cracking furnace apparatus as claimed in any one of claims 1 to 5, wherein: the inside bottom surface of stove box (1) is provided with stove coil pipe support frame (4), stove coil pipe (2) are arranged in on stove coil pipe support frame (4), stove coil pipe support frame (4) include two parallel arrangement's main tributary stay tube (5), main tributary stay tube (5) are along the direction setting that stove coil pipe (2) extend, and its first end is connected with the curb plate of stove box (1), and the second end is connected with the bottom plate of stove box.

7. The steam cracking furnace apparatus for hydrocarbon according to claim 6, wherein: the second end of main tributary stay tube (5) is provided with fender pipe (6) perpendicularly and fixedly, be provided with between the second end of fender pipe (6) and main tributary stay tube (5) oblique stay tube (7).

8. The steam cracking furnace apparatus for hydrocarbon according to claim 6, wherein: the side plates, the top plate and the bottom plate of the furnace box body (1) comprise steel plates on the outermost sides, supporting frames fixedly arranged on steel structures on the inner sides of the steel plates and heat preservation and insulation layers (21), the inner sides of the bottom plate are arranged along the main supporting pipes (5) and are provided with a plurality of furnace supporting bodies (8), and the main supporting pipes (5) are supported by the furnace supporting bodies (8).

9. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: a plurality of heating band connecting holes (33) have been seted up to the both sides wall of furnace box body (1), heating band connecting hole (33) are used for setting up the stick of drawing forth of electric heat tape (11), it is provided with the bakelite seat to draw forth between stick and heating band connecting hole (33).

10. The steam cracking furnace apparatus for hydrocarbon according to claim 1, wherein: the cracking furnace is characterized in that a plurality of box supporting feet (10) are arranged at the bottom of the furnace box body (1), concrete for a ground foundation where the cracking furnace device is located is poured, the upper surface of the bottom plate of each box supporting foot (10) is flush with the upper surface of the concrete foundation, at least two embedded parts (35) are fixedly arranged at the bottom of the bottom plate of each box supporting foot (10), and the embedded parts (35) are embedded in the concrete foundation.

Images