CN115615231B

CN115615231B - Medium-pressure steam replacing tubular furnace to heat rich oil process and equipment

Info

Publication number: CN115615231B
Application number: CN202211617301.XA
Authority: CN
Inventors: 商恩霞; 柴云富; 赵顺雯; 周丽强
Original assignee: TIANJIN CHUANGJU TECHNOLOGY CO LTD
Current assignee: TIANJIN CHUANGJU TECHNOLOGY CO LTD
Priority date: 2022-12-16
Filing date: 2022-12-16
Publication date: 2023-04-07
Anticipated expiration: 2042-12-16
Also published as: CN115615231A

Abstract

The invention relates to the technical field of rich oil heating, in particular to a process and equipment for heating rich oil by medium-pressure steam instead of a tubular furnace. According to the technical scheme, medium-pressure steam is used as a heat source, an open fire heating tube furnace in a crude benzene area is omitted, and steam moving from bottom to top in the rich oil heater performs uniform and coincident heat exchange on rich oil flowing from top to bottom in an oil pipe.

Description

Medium-pressure steam replacing tubular furnace to heat rich oil process and equipment

Technical Field

The invention relates to the technical field of rich oil heating, in particular to a process for heating rich oil by replacing a tubular furnace with medium-pressure steam, and further relates to equipment for heating rich oil by replacing the tubular furnace with the medium-pressure steam.

Background

At present, in the crude benzene section production of coking enterprises, rich oil from a benzene washing tower firstly enters a lean-rich oil heat exchanger, is heated to about 140-150 ℃ together with hot lean oil discharged from the bottom of a debenzolization tower, and then is sent into a tubular furnace, and the rich oil is heated to 180-190 ℃ by coal gas in the tubular furnace and then enters the debenzolization tower. And after heat exchange is carried out on the hot lean oil and the rich oil, the hot lean oil is sequentially sent into a first-stage lean oil cooler and a second-stage lean oil cooler for further cooling, and the cold lean oil is sent to a benzene washing tower for recycling. In the negative pressure debenzolization process, the debenzolization tower also needs a tubular furnace to heat the lean oil to provide a heat source. The tubular furnace heating has a large number of environmental protection problems, safety problems, land occupation problems and operation problems.

1. The environmental protection problem is as follows: the tube furnace uses coal gas as fuel, and chimney exhaust gas is directly discharged into the atmosphere. The flue gas contains SO ₂ 、NO _x And harmful substances such as CO and the like and smoke pollute the environment. If the flue gas is subjected to desulfurization and denitrification treatment, the corresponding equipment investment is required to be increased, and the operating cost and the labor cost are also increased.

2. Safety problems are as follows: the tubular furnace belongs to open fire equipment, has potential safety hazard in the use process, and seriously influences the safety production of a crude benzene workshop section.

3. The land occupation problem is as follows: according to the chemical design specification, a safe fire-proof distance of 15 meters needs to be reserved around the tube furnace, and other equipment cannot be arranged in the area. This results in a large land area.

4. The operation problem is as follows: the high-temperature local heating of the tube furnace at 800-850 ℃ causes the cracking carbonization of the wash oil, reduces the quality of the wash oil, increases the consumption of the wash oil, the consumption of the wash oil is about 60kg/t benzene, and the poor and rich oil heat exchanger is easy to block, thereby affecting the heat exchange effect and increasing the energy consumption.

5. In the existing medium-pressure steam heating rich oil process, the temperature of medium-pressure steam condensate from a rich oil heater is higher, and the direct cooling heat waste is serious, so the medium-pressure steam condensate is sent to a flash evaporation tank for pressure reduction (reduced to 0.6 MPa) flash evaporation, and finally low-pressure saturated steam and low-pressure steam condensate are obtained, which belong to secondary recovery of heat, but the recovered low-grade heat source (low-pressure saturated steam) is low in recovery value.

Disclosure of Invention

The medium-pressure steam is used as a heat source, the open fire heating tube furnace in a crude benzene region is eliminated, and steam moving from bottom to top in the rich oil heater performs uniform heat exchange on rich oil flowing from top to bottom in an oil pipe.

In order to solve the problems of the prior art, the invention adopts the technical scheme that:

a medium-pressure steam heating oil-rich process replacing a tube furnace comprises the following steps:

the method comprises the following steps: leading the rich oil into a lean-rich oil heat exchanger to exchange heat with the lean oil;

step two: the rich oil after heat exchange in the step one enters a rich oil preheater for heat exchange;

step three: heating the rich oil subjected to heat exchange in the step two in a rich oil heater;

step four: the rich oil heated in the third step enters a debenzolization tower for rectification;

the heat source for heating the rich oil in the third step is medium-pressure superheated steam generated by dry quenching; in the second step, the heat source for exchanging heat with the rich oil comes from steam condensate generated by a rich oil heater; cooling the steam condensate after heat exchange with the rich oil in the step two through a condenser, and then feeding the cooled steam condensate into dry quenching coke for recycling;

the oil-rich heater comprises a tank body with an inner cavity, the tank body is provided with a steam inlet pipe positioned below and a steam discharge pipe positioned above, the tank body is also internally provided with an oil pipe which enters from the top of the tank body and penetrates out from the bottom of the tank body, the tank body is also internally provided with an annular cavity positioned at the middle upper part of the tank body, the steam discharge pipe is provided with an air guide pipe extending into the annular cavity, and the side part of the tank body is also provided with a liquid discharge pipe communicated with the annular cavity.

The utility model provides a middling pressure steam replaces tubular furnace heating rich oil equipment, is applied to a middling pressure steam replaces tubular furnace heating rich oil technology, including the rich oil heater, the rich oil heater is including the jar body that has the inner chamber, this jar body has the steam admission pipe that is located the below and the steam discharge pipe that is located the top, jar internal oil pipe that still is equipped with from jar body top entering and wear out from jar body bottom, jar internal still shaping has the annular chamber that is located jar body middle and upper portion, the steam discharge pipe is equipped with the air duct that extends to the annular chamber, jar body lateral part still is equipped with the fluid-discharge tube with the annular chamber intercommunication.

Preferably, a partition plate is arranged on the upper side in the tank body, the partition plate surrounds the periphery of the tank body, and an annular cavity is formed by the interval between the partition plate and the inner wall of the tank body;

preferably, the steam discharge pipe is communicated with the cavity inside the partition plate and the outside of the tank body; the partition board has an inner diameter gradually reduced from bottom to top.

Preferably, an inclined condensation plate is arranged at the bottom of the annular cavity, and a liquid discharge pipe is arranged at the lower end of the condensation pipe.

Preferably, at least one connecting piece is arranged in the annular cavity and is connected with the inner wall of the tank body and the partition plate. The oil pipe is arranged on a pipe plate arranged at the bottom of the tank body, a support frame is arranged on one side of the pipe plate facing the inside of the tank body, and the oil pipe is spirally arranged on the support frame. The top end of the tank body is provided with an oil inlet cavity, and the oil inlet cavity is communicated with the partition plate through a positioning channel; when the tube plate is arranged at the bottom of the tank body, the top end of the oil pipe is inserted into the positioning channel.

Preferably, the top of the tank body is provided with an upper sealing cover, the upper sealing cover is hermetically arranged at an opening at the upper end of the oil inlet cavity, and the upper sealing cover is provided with an oil inlet channel; and a filter box is arranged in the oil inlet cavity and is used for removing impurities of the rich oil flowing into the positioning channel.

Preferably, the top of the support frame is provided with a hoop, the top end of the oil pipe is installed in the hoop, and the hoop and the axis of the positioning channel are in the same straight line.

Preferably, the tube plate is provided with a vertically through insertion hole; the skirt is installed to jar body below, and the skirt is fixed the position of tube sheet, is provided with the oil outlet channel with the coaxial setting of cartridge hole on the skirt, and the cartridge hole cartridge that the tube sheet was passed to the oil pipe bottom is in oil outlet channel.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the process, medium-pressure steam is used as a heat source, open fire heating of the tube furnace in the crude benzene area is omitted, equipment investment and operation cost for modification of desulfurization and denitrification of tail gas of the tube furnace are saved, increased labor cost is saved, and the safe production level of the crude benzene area is improved.

2. According to the device, steam is introduced into the tank body through the steam inlet pipe at the bottom of the tank body and moves upwards in the tank body, rich oil flows from top to bottom through the oil pipe, the temperature above the tank body is low, but the rich oil can be preheated with the rich oil which just enters the tank body in the oil pipe in the process of moving upwards, so that the temperature of the rich oil moving to the bottom of the tank body is increased more quickly, and the steam heat exchange efficiency is improved, so that the heating efficiency of the rich oil heater for heat exchange is improved.

3. According to the invention, the annular cavity is formed in the tank body through the partition plate, when the steam is discharged from the steam discharge pipe, water vapor is introduced into the annular cavity through the gas guide pipe to be condensed, the formed condensed water is discharged from the rich oil heater through the liquid discharge pipe and is conveyed to the rich oil preheater to preheat the rich oil, and the annular cavity is positioned at the lower temperature part of the tank body and is beneficial to steam condensation.

4. According to the invention, the partition plate has the inner diameter gradually reduced from bottom to top, so that the passing area is gradually reduced in the upward moving process of steam, the pressure of the steam losing part of heat is gradually increased when the steam moves in the gradually reduced channel, and the steam is in closer contact with the oil pipe, so that the residual heat can be more effectively transferred to rich oil in the oil pipe, and the heat exchange efficiency of the steam is improved.

5. According to the invention, the rich oil is preheated and heated through the medium-pressure steam condensate from the rich oil heater, so that the temperature of the rich oil entering the rich oil heater is increased while the rich oil is cooled, and the medium-pressure steam consumption of the rich oil heater is reduced.

Drawings

FIG. 1 is a schematic flow diagram of a process for heating rich oil using medium pressure steam instead of a tube furnace;

FIG. 2 is a front view of a device for heating the rich oil using medium pressure steam instead of a tube furnace;

FIG. 3 is a side view of an apparatus for heating rich oil using medium pressure steam instead of a tube furnace;

FIG. 4 isbase:Sub>A plan sectional view at A-A of FIG. 3;

FIG. 5 is a partial enlarged view of FIG. 4 at B;

FIG. 6 is a partial enlarged view at C of FIG. 4;

FIG. 7 isbase:Sub>A perspective cross-sectional view taken at A-A of FIG. 3;

FIG. 8 is an enlarged view of a portion of FIG. 7 at D;

fig. 9 is a perspective view of an oil pipe of a device for heating rich oil by medium pressure steam instead of a tube furnace.

The reference numbers in the figures are:

1-a rich oil heater;

11-a tank body;

111-steam inlet pipe;

112-a steam discharge pipe;

113-ring cavity;

1131, airway tube; 1132-cold plate;

114-drain pipe;

115-a separator;

1151-a positioning channel;

116-connecting pieces;

117-oil inlet chamber;

1171-a filtration cassette;

12-an oil pipe;

121-a tube sheet;

1211-a support frame;

1212-a hoop;

1213-insertion holes;

13-upper cover;

131-an oil inlet channel;

14-skirt;

141-a water outlet channel;

2-a pressure reduction device; 3-a rich oil preheater; 4-a condenser; 5-a debenzolization column; 6-lean-rich oil heat exchanger.

Detailed Description

For further understanding of the features and technical means of the present invention, as well as the specific objects and functions attained by the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description.

Referring to fig. 1 to 9: a medium-pressure steam heating oil-rich process replacing a tube furnace comprises the following steps: the method comprises the following steps: leading the rich oil into a lean-rich oil heat exchanger 6 to exchange heat with the lean oil;

step two: the rich oil after heat exchange in the step one enters a rich oil preheater 3 for heat exchange;

step three: the rich oil after heat exchange in the step two enters a rich oil heater 1 for heating;

step four: the rich oil heated in the third step enters a debenzolization tower 5 for rectification;

the heat source for heating the rich oil in the third step is medium-pressure superheated steam generated by dry quenching; the heat source for exchanging heat with the rich oil in the step two comes from steam condensate generated by the rich oil heater 1; cooling the steam condensate subjected to heat exchange with the rich oil in the step two through a condenser 4, and then feeding the cooled steam condensate into dry quenching coke for recycling;

the rich oil heater 1 comprises a tank body 11 with an inner cavity, the tank body 11 is provided with a steam inlet pipe 111 positioned at the lower part and a steam outlet pipe 112 positioned at the upper part, an oil pipe 12 which enters from the top part of the tank body 11 and penetrates out from the bottom part of the tank body 11 is further arranged in the tank body 11, an annular cavity 113 positioned at the middle upper part of the tank body 11 is further formed in the tank body 11, the steam outlet pipe 112 is provided with an air guide pipe 1131 extending into the annular cavity 113, and a liquid outlet pipe 114 communicated with the annular cavity 113 is further arranged at the side part of the tank body 11.

When the steps are adopted to process the rich oil, the rich oil from the benzene washing tower at the crude benzene section is subjected to heat exchange with the lean oil through the lean and rich oil heat exchanger 6, the temperature is about 140 ℃, the rich oil enters the rich oil preheater 3 for preheating, the heat source is steam condensate produced by the rich oil heater 1, and the rich oil is preheated to 150 ℃. After preheating the rich oil, the rich oil enters a rich oil heater 1, the heat source is about 3MPa of medium-pressure superheated steam pressure from dry quenching, the temperature is about 400 ℃, and the rich oil is heated to 185 ℃. After the rich oil is heated, the rich oil enters a debenzolization tower 5 for rectification. Medium-pressure superheated steam from dry quenching is about 3MPa in pressure and about 400 ℃ in temperature, and is divided into two parts, wherein one part is used as a heat source and enters a rich oil heater 1, the other part is subjected to secondary decompression through a decompression device 2 to generate low-pressure superheated steam with pressure of about 0.5MPa and temperature of about 380 ℃, and the low-pressure superheated steam enters a regenerator for washing oil and regenerating. After preheating the rich oil by the steam condensate generated by the rich oil heater 1, the rich oil enters the condenser 4 to be cooled to about 80 ℃, and returns to the dry quenching coke for recycling by means of self pressure. When the process is adopted to heat the rich oil, because coal gas is not used as a heat source, the equipment investment, the operation cost and the increased labor cost for the modification of the desulfurization and the denitration of the tail gas of the tubular furnace are saved; the open fire heating tube furnace in the crude benzene area is cancelled, so that the safe production level of the crude benzene area is improved; compared with the high temperature of 800-850 ℃ in a hearth of a tubular furnace, medium-pressure steam is used as a heat source, the steam temperature is 400 ℃, the temperature is much lower, heat exchange tubes in the rich oil heater 1 are uniformly distributed, the heating process is softer, the molecular polymerization condition of the rich oil caused by overhigh local temperature is greatly weakened, the quality deterioration of wash oil is slowed down, the consumption of the wash oil is reduced, and the consumption of 60kg/t crude benzene can be reduced to 40kg/t crude benzene; the medium-pressure steam condensate from the rich oil heater 1 preheats and raises the temperature of rich oil, the temperature of the rich oil entering the rich oil heater 1 is lowered, the step of pressure reduction and flash evaporation in a flash tank in the prior art is omitted, the medium-pressure steam consumption of the rich oil heater 1 is directly reduced, and compared with other processes for obtaining low-pressure saturated steam by flash evaporation of the medium-pressure steam condensate, the process reduces the consumption of medium-pressure steam.

Referring to fig. 2 to 4: the utility model provides a middling pressure steam replaces tubular furnace heating rich oil equipment, be applied to a middling pressure steam replaces tubular furnace heating rich oil technology, including rich oil heater 1, rich oil heater 1 is including the jar body 11 that has the inner chamber, this jar body 11 has steam admission pipe 111 that is located the below and is located the steam discharge pipe 112 of top, still be equipped with in jar body 11 from jar body 11 top entering and the oil pipe 12 that wears out from jar body 11 bottom, still the shaping has the annular chamber 113 that is located jar body 11 middle and upper portion in jar body 11, steam discharge pipe 112 is equipped with the air duct 1131 that extends to the annular chamber 113, jar body 11 lateral part still is equipped with the fluid-discharge tube 114 with annular chamber 113 intercommunication.

During processing, medium-pressure steam is introduced into the tank body 11 through the steam inlet pipe 111 at the bottom of the tank body 11 and moves upwards in the tank body 11, rich oil flows from top to bottom through the oil pipe 12, the steam at the bottom of the tank body 11 is high in temperature and uniformly heats the rich oil in the oil pipe 12, heat contained in the steam is transferred into the rich oil, the steam after heat exchange moves upwards and is discharged from a steam outlet at the top of the tank body 11, the steam above the tank body 11 is low in temperature and can be preheated with the rich oil which just enters the tank body 11 in the oil pipe 12 in the upwards moving process, the temperature of the rich oil moving to the bottom of the tank body 11 is increased more quickly, and the steam heat exchange efficiency is improved, so that the heating efficiency of the heat-exchange rich oil heater 1 is improved. The temperature is lower in the inside formation top of jar body 11, and the below temperature is higher, and annular cavity 113 is arranged in the lower position of the upper portion temperature in jar body 11, introduces steam through air duct 1131 and gets into annular cavity 113 and condenses when steam discharge pipe 112 exhaust steam, forms the comdenstion water and passes through drain pipe 114 discharge rich oil heater 1 and carry and preheat rich oil in the rich oil preheater 3, and annular cavity 113 is arranged in jar body 11 lower position of temperature and is favorable to the steam condensation.

Referring to fig. 1, 4 and 7: a partition plate 115 is arranged on the upper side in the tank body 11, the partition plate 115 surrounds the periphery of the tank body 11, and an annular cavity 113 is formed by the distance between the partition plate 115 and the inner wall of the tank body 11; the steam discharge pipe 112 communicates the cavity inside the partition 115 with the outside of the tank 11; the partition 115 has an inner diameter gradually decreasing from bottom to top.

The baffle 115 inside the tank body 11 cooperates with the inner wall of the tank body 11 to form the annular cavity 113, when steam moves upwards, because the baffle 115 has an inner diameter gradually reduced from bottom to top, the area is gradually reduced in the upward moving process of the steam, the pressure of the steam losing part of heat is gradually increased when the steam moves in a gradually reduced channel, the steam is in closer contact with the oil pipe 12, and therefore the residual heat can be more effectively transferred to rich oil in the oil pipe 12, and the heat exchange efficiency of the steam is improved.

Referring to fig. 4, 6 and 7: an inclined condensation plate 1132 is arranged at the bottom of the annular cavity 113, and a drain 114 is arranged at the lower end of the condensation pipe.

During steam discharge pipe 112 output steam, air duct 1131 will communicate steam discharge pipe 112 and annular chamber 113, set up the condensation plate 1132 of slope in the annular chamber 113, the higher one end of condensation plate 1132 leans on air duct 1131 to set up, condensation plate 1132 makes through semiconductor material, can make condensation plate 1132 cool down through the circular telegram to condensation plate 1132, and then condense at condensation plate 1132 surface moisture in the steam, the condensate flows to lower one end along condensation plate 1132 under the action of gravity, discharge tube 114 through the lower one end of condensation plate 1132 discharges, preheat the rich oil in the entering rich oil preheater 3.

Referring to fig. 4 and 7: at least one connecting piece 116 is arranged in the annular cavity 113, and the connecting piece 116 is connected with the inner wall of the tank body 11 and the partition plate 115.

Because the condensation of steam takes place for the one side of baffle 115 near air duct 1131, steam condensation is a large amount of heats of production, in order to prevent that baffle 115 from warping, this embodiment is provided with connecting piece 116 in annular chamber 113, connecting piece 116 can encircle jar body 11 axis setting, also can vertical setting, the quantity of connecting piece 116 is no less than one, thereby connecting piece 116 and jar body 11 inner wall and baffle 115 and strengthening the support to the structure of baffle 115, prevent that the inhomogeneous baffle 115 that causes of the inside and outside pressure of baffle 115 and temperature warp.

Referring to fig. 4 and 9: the oil pipe 12 is installed on a pipe plate 121 installed at the bottom of the tank 11, a support 1211 is installed on one side of the pipe plate 121 facing the inside of the tank 11, and the oil pipe 12 is spirally installed on the support 1211.

In order to make the rich oil in the oil pipe 12 stay in the tank 11 for a longer time, the oil pipe 12 of this embodiment is spirally disposed inside the tank 11, the oil pipe 12 is mounted on the tube plate 121, the tube plate 121 is provided with a support 1211, the oil pipe 12 can be spirally wound on the support 1211, the support 1211 is composed of a plurality of vertical straight rods, so that the steam can enter the interior of the support 1211 to contact with the oil pipe 12, thereby improving the heat transfer efficiency, the oil pipe 12 is spirally disposed, the rich oil in the oil pipe 12 can be moved from top to bottom in the oil pipe 12 in a unidirectional manner, the flow of the rich oil is ensured by matching with gravity, the pressure on the oil pipe 12 is small, and the service life of the oil pipe 12 is also ensured.

Referring to fig. 4, 5, 7 and 9: an oil inlet cavity 117 is formed in the top end of the tank body 11, and the oil inlet cavity 117 is communicated with the partition plate 115 through a positioning channel 1151; when the tube plate 121 is installed at the bottom of the tank 11, the top end of the oil pipe 12 is inserted into the positioning passage 1151.

An upper sealing cover 13 is arranged at the top of the tank body 11, the upper sealing cover 13 is hermetically arranged at an opening at the upper end of the oil inlet cavity 117, and an oil inlet channel 131 is arranged on the upper sealing cover 13; a filter box 1171 is arranged in the oil inlet cavity 117, and the filter box 1171 removes impurities from the rich oil flowing into the positioning channel 1151.

The oil pipe 12 is arranged on the pipe plate 121, so that the oil pipe 12 can be installed and detached through the installation and connection of the pipe plate 121 and the tank body 11, the operation difficulty of maintenance is reduced, the oil inlet cavity 117 at the top of the tank body 11 is blocked by the upper sealing cover 13, rich oil entering the rich oil heater 1 enters the oil inlet cavity 117 through the oil inlet channel 131 at the upper sealing cover 13 above the tank body 11 and enters the oil pipe 12 through the positioning channel 1151 to move, when the pipe plate 121 is arranged at the bottom of the tank body 11, the top end of the oil pipe 12 is inserted into the positioning channel 1151, the directional movement of the rich oil is ensured, and when the rich oil moves to the positioning channel 1151 from the oil inlet cavity 117, the filter box 1171 can filter impurities in the rich oil, so that the oil pipe 12 is prevented from being damaged.

Referring to fig. 7 to 9: the top of the support 1211 is provided with a ferrule 1212, the top end of the tubing 12 is mounted in the ferrule 1212, and the ferrule 1212 is aligned with the axis of the positioning channel 1151.

The tube plate 121 is provided with a vertically through insertion hole 1213; a skirt 14 is mounted below the tank 11, the skirt 14 fixes the position of the tube plate 121, an oil outlet channel coaxial with the insertion hole 1213 is arranged on the skirt 14, and the bottom end of the oil pipe 12 passes through the insertion hole 1213 of the tube plate 121 and is inserted in the oil outlet channel.

When the oil pipe 12 is installed on the tube plate 121, in order to facilitate the connection of the oil pipe 12 with the positioning channel 1151 at the top of the tank 11, the top end of the support 1211 of the tube plate 121 is provided with a hoop 1212, the oil pipe 12 is wound on the support 1211, and the top end of the oil pipe 12 is installed in the hoop 1212, so as to ensure that the top end of the oil pipe 12 is in the same straight line with the axis of the tube plate 121, the bottom of the oil pipe 12 is inserted into the insertion hole 1213 of the tube plate 121, when the tube plate 121 is installed at the bottom of the tank 11, the top end of the oil pipe 12 is naturally inserted into the positioning channel 1151 in the same straight line with the axis of the tube plate 121, at this time, the skirt 14 is installed below the tank 11, the lower end of the oil pipe 12 penetrating through the tube plate 121 is inserted into the oil outlet channel on the skirt 14, and the heated rich oil flows out of the tank 11 conveniently.

The above examples, which are intended to represent only one or more embodiments of the present invention, are described in greater detail and with greater particularity, and are not to be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A medium-pressure steam replaces a tubular furnace to heat rich oil, and is characterized by comprising the following steps:

the method comprises the following steps: leading the rich oil into a lean-rich oil heat exchanger (6) to exchange heat with the lean oil;

step two: the rich oil after heat exchange in the step one enters a rich oil preheater (3) for heat exchange;

step three: the rich oil after heat exchange in the step two enters a rich oil heater (1) to be heated;

step four: the rich oil heated in the third step enters a debenzolization tower (5) for rectification;

the heat source for heating the rich oil in the third step is medium-pressure superheated steam generated by dry quenching; the heat source for exchanging heat with the rich oil in the step two comes from steam condensate generated by the rich oil heater (1); cooling the steam condensate after heat exchange with the rich oil in the step two through a condenser (4) and then feeding the cooled steam condensate into dry quenching coke for recycling;

the oil-rich heater (1) comprises a tank body (11) with an inner cavity, the tank body (11) is provided with a steam inlet pipe (111) positioned below and a steam outlet pipe (112) positioned above, an oil pipe (12) which enters from the top of the tank body (11) and penetrates out of the bottom of the tank body (11) is further arranged in the tank body (11), an annular cavity (113) positioned at the middle upper part of the tank body (11) is further formed in the tank body (11), the steam outlet pipe (112) is provided with an air guide pipe (1131) extending into the annular cavity (113), and a liquid outlet pipe (114) communicated with the annular cavity (113) is further arranged on the side part of the tank body (11);

a partition plate (115) is arranged on the upper side in the tank body (11), the partition plate (115) surrounds the periphery of the tank body (11), and an annular cavity (113) is formed by the distance between the partition plate (115) and the inner wall of the tank body (11);

the steam discharge pipe (112) is communicated with the cavity inside the partition plate (115) and the outside of the tank body (11);

the partition plate (115) has an inner diameter gradually decreasing from bottom to top;

an inclined condensation plate (1132) is arranged at the bottom of the annular cavity (113), and a liquid discharge pipe (114) is arranged at the lower end of the condensation pipe;

at least one connecting piece (116) is arranged in the annular cavity (113), and the connecting piece (116) is connected with the inner wall of the tank body (11) and the partition plate (115).

2. The medium-pressure steam heating oil-rich process replacing a tube furnace as claimed in claim 1, wherein the oil pipe (12) is installed on a tube plate (121) installed at the bottom of the tank body (11), a support frame (1211) is arranged on one side of the tube plate (121) facing the inside of the tank body (11), and the oil pipe (12) is spirally installed on the support frame (1211).

3. The medium-pressure steam heating oil-rich process replacing a tube furnace according to claim 2, characterized in that an oil inlet cavity (117) is formed at the top end of the tank body (11), and the oil inlet cavity (117) is communicated with the partition plate (115) through a positioning channel (1151); when the tube plate (121) is arranged at the bottom of the tank body (11), the top end of the oil pipe (12) is inserted into the positioning channel (1151).

4. The medium-pressure steam heating oil-rich process replacing a tube furnace as claimed in claim 3, wherein an upper sealing cover (13) is mounted at the top of the tank body (11), the upper sealing cover (13) is hermetically mounted at an opening at the upper end of the oil inlet cavity (117), and an oil inlet channel (131) is arranged on the upper sealing cover (13);

a filter box (1171) is arranged in the oil inlet cavity (117), and the filter box (1171) removes impurities from the rich oil flowing into the positioning channel (1151).

5. The process of claim 3, wherein a hoop ring (1212) is arranged on the top of the support frame (1211), the top end of the oil pipe (12) is installed in the hoop ring (1212), and the hoop ring (1212) is in the same line with the axis of the positioning channel (1151).

6. The medium-pressure steam heating oil-rich process replacing a tube furnace according to claim 5, characterized in that a tube plate (121) is provided with a vertically through plug-in hole (1213);

skirt bases (14) are installed below the tank body (11), the skirt bases (14) fix the position of the tube plate (121), oil outlet channels which are coaxial with the insertion holes (1213) are formed in the skirt bases (14), and the bottom ends of the oil pipes (12) penetrate through the insertion holes (1213) of the tube plate (121) and are inserted into the oil outlet channels.