Crude benzene hydrofining purification system

Abstract

The utility model relates to a crude benzene hydrofining purification system, which comprises a stabilizing tower, an extraction tower, a heat exchanger, a distillation tower, a condenser and a condensate storage tank, the stabilizing tower is connected with the extraction tower, the extraction tower is connected with the heat exchanger, the heat exchanger is connected with the distillation tower, the distillation tower is connected with the condenser, and the condensate storage tank is connected with the condenser. The condenser is connected with the condensate storage tank, a fourth conveying pipe is arranged between the heat exchanger and the distillation tower, the fourth conveying pipe is communicated with an outlet of the heat exchanger, two heat preservation and insulation assemblies are arranged outside the fourth conveying pipe, the fourth conveying pipe is arranged between the two heat preservation and insulation assemblies, and the heat preservation and insulation assemblies are communicated with the heat exchanger. The heat preservation and insulation assembly comprises a pipe hoop, first heat preservation layers arranged on the pipe hoop and second heat preservation layers, the first heat preservation layers are arranged on the inner surface of the pipe hoop, the second heat preservation layers are arranged on the first heat preservation layers, and the fourth conveying pipe is contained between the two second heat preservation layers.

Description

Technical Field

[0001] The utility model belongs to the technical field of crude benzene hydrogenation, in particular to a crude benzene hydrogenation refining and purification system. Background Art

[0002] Crude benzene is one of the products of crude coal gas generated by coal pyrolysis. The benzene compounds recovered from the coke oven gas after deammoniation, of which benzene content is the main component, are called crude benzene. There are two processes for processing crude benzene in China. One is the ancient acid washing purification method, and the other is the advanced hydrogenation refining method. Crude benzene hydrogenation refining refers to the process of removing various impurities in crude benzene by chemical reaction of benzene with hydrogen through a catalyst bed under a certain reaction temperature and hydrogen pressure, and then distilling to obtain benzene products.

[0003] The benzene products obtained after the crude benzene is distilled are a mixture of benzene, toluene and xylene. The benzene mixture needs to be further purified to separate benzene, toluene and xylene. The existing purification system does not have a preheating and heat preservation process for the crude benzene, which is prone to slow heating efficiency of the raw materials. Moreover, slow heating will cause low distillation purification efficiency and affect the production speed. Therefore, there are still shortcomings and deficiencies in the existing technology. Utility Model Content

[0004] The utility model aims to provide a crude benzene hydrogenation refining and purification system to solve the above problems.

[0005] In order to solve the above problems, the technical solution adopted by the utility model is:

[0006] A crude benzene hydrorefining and purification system is provided, comprising a stabilization tower, an extraction tower, a heat exchanger, a distillation tower, a condenser and a condensate storage tank, wherein the stabilization tower is connected to the extraction tower, the extraction tower is connected to the heat exchanger, the heat exchanger is connected to the distillation tower, the distillation tower is connected to the condenser, the condenser is connected to the condensate storage tank, a fourth delivery pipe is arranged between the heat exchanger and the distillation tower, the fourth delivery pipe is connected to the outlet of the heat exchanger, two groups of thermal insulation components are arranged outside the fourth delivery pipe, and the fourth delivery pipe is arranged between the two groups of thermal insulation components. The thermal insulation component includes a pipe clamp, a first thermal insulation layer arranged on the pipe clamp, and a second thermal insulation layer, wherein the first thermal insulation layer is arranged on the inner surface of the pipe clamp, and the second thermal insulation layer is arranged on the first thermal insulation layer. The two pipe clamps in the two groups of the thermal insulation components are detachably connected, and the fourth delivery pipe is accommodated between the two second thermal insulation layers. Two tube sheets are arranged in the heat exchanger, and the tube sheets are symmetrically arranged at both ends of the heat exchanger. The tube sheets are arranged vertically, and a plurality of through holes are opened on the tube sheets. The through holes on the two tube sheets are arranged one by one, and connecting pipes are connected one by one between the through holes on the two tube sheets. A temperature sensor is also installed in the heat exchanger, and a steam inlet pipe and a condensate outlet pipe are arranged on the heat exchanger.

[0007] Furthermore, a first delivery pipe is provided on the stabilizing tower, and the first delivery pipe is connected with the interior of the stabilizing tower.

[0008] Furthermore, a second delivery pipe is provided between the stabilization tower and the extraction tower, and both ends of the second delivery pipe are respectively connected to the stabilization tower and the extraction tower.

[0009] Furthermore, a third delivery pipe is provided between the extraction tower and the heat exchanger, and the third delivery pipe is connected to the inlet of the heat exchanger.

[0010] Furthermore, a fifth delivery pipe is provided between the distillation tower and the condenser, and both ends of the fifth delivery pipe are respectively connected to the distillation tower and the condenser.

[0011] Furthermore, a sixth delivery pipe is provided between the condenser and the condensate storage tank, and both ends of the sixth delivery pipe are respectively connected to the condenser and the condensate storage tank.

[0012] Furthermore, the two pipe clamps in the two groups of thermal insulation components are detachably connected by bolts.

[0013] Furthermore, a temperature sensor is installed in the heat exchanger.

[0014] Furthermore, the steam inlet pipe is arranged at the top of the heat exchanger, and the condensate outlet pipe is arranged at the bottom of the heat exchanger.

[0015] By adopting the above technical solution, the beneficial effects of the utility model are:

[0016] The crude benzene hydrogenation refining and purification system of the utility model comprises a stabilization tower, an extraction tower, a heat exchanger, a distillation tower, a condenser and a condensate storage tank. The mixture obtained by extraction and separation is subjected to heat exchange and temperature increase in the heat exchanger, thereby preheating the mixture and increasing the temperature of the mixture. The mixture is fully in contact with high-temperature hot steam in a plurality of connecting pipes in the heat exchanger, thereby improving the heat exchange efficiency. By arranging a heat preservation and heat insulation component outside the fourth conveying pipe, the hot mixture in the fourth conveying pipe after heat exchange can be insulated, thereby avoiding heat loss in the mixture and improving the efficiency of subsequent distillation treatment. By collecting liquids evaporated at different temperatures, benzene, toluene and xylene with higher purity can be obtained, thereby realizing separation and purification after crude benzene hydrogenation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the crude benzene hydrogenation refining and purification system in the utility model.

[0018] Figure 2 It is a structural cross-sectional view of the fourth delivery pipe and the thermal insulation component.

[0019] Figure 3 for Figure 1 Schematic diagram of the cross-sectional structure of the heat exchanger.

[0020] Figure numerals: 10, stabilization tower; 11, first delivery pipe; 12, second delivery pipe; 20, extraction tower; 21, third delivery pipe; 30, heat exchanger; 31, fourth delivery pipe; 32, thermal insulation assembly; 321, pipe clamp; 322, first insulation layer; 323, second insulation layer; 33, tube sheet; 331, through hole; 34, connecting pipe; 35, steam inlet pipe; 36, condensate outlet pipe; 37, temperature sensor; 40, distillation tower; 41, fifth delivery pipe; 50, condenser; 51, sixth delivery pipe; 60, condensate storage tank. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the utility model clearer, the utility model is now described in detail in conjunction with the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basics of the utility model in a schematic manner, so it only shows the structure related to the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0022] like Figure 1 As shown, the utility model provides a crude benzene hydrogenation refining and purification system for purifying a mixture after a hydrogenation reaction of crude benzene. The crude benzene hydrogenation refining and purification system comprises a stabilization tower 10, an extraction tower 20, a heat exchanger 30, a distillation tower 40, a condenser 50 and a condensate storage tank 60.

[0023] like Figure 1 As shown, the stabilization tower 10 is connected to the extraction tower 20, the extraction tower 20 is connected to the heat exchanger 30, the heat exchanger 30 is connected to the distillation tower 40, the distillation tower 40 is connected to the condenser 50, and the condenser 50 is connected to the condensate storage tank 60.

[0024] like Figure 1 As shown, the stabilization tower 10 is provided with a first delivery pipe 11, which is connected to the interior of the stabilization tower 10. The reaction product obtained after the hydrogenation reaction of crude benzene is transported into the stabilization tower 10 through the first delivery pipe 11. The acid gas is removed from the reaction product in the stabilization tower 10, and finally the hydrogenated oil containing thiophene less than 0.5 mg / kg is obtained in the stabilization tower 10.

[0025] like Figure 1 As shown, a second delivery pipe 12 is provided between the stabilization tower 10 and the extraction tower 20, and both ends of the second delivery pipe 12 are respectively connected to the stabilization tower 10 and the extraction tower 20. The hydrogenated oil obtained after removing the acid gas in the stabilization tower 10 is transported into the extraction tower 20 through the second delivery pipe 12. The hydrogenated oil transported into the extraction tower 20 is subjected to liquid-liquid extraction, and non-aromatic hydrocarbons and a mixture are obtained by extraction and separation. The above mixture is a mixture of benzene, toluene and xylene.

[0026] like Figure 1As shown, a third delivery pipe 21 is provided between the extraction tower 20 and the heat exchanger 30, and the third delivery pipe 21 is connected with the inlet of the heat exchanger 30. The mixture obtained by extraction and separation in the extraction tower 20 is delivered into the heat exchanger 30 through the third delivery pipe 21. The mixture is heated by heat exchange in the heat exchanger 30, thereby preheating the mixture and increasing the temperature of the mixture to facilitate subsequent distillation operations.

[0027] like Figure 3 As shown, two tube sheets 33 are arranged in the heat exchanger 30, and the tube sheets 33 are symmetrically arranged at both ends of the heat exchanger 30. The tube sheets 33 are arranged vertically, and a plurality of through holes 331 are opened on the tube sheets 33. The through holes 331 on the two tube sheets 33 are arranged one by one, and connecting pipes 34 are connected one by one between the through holes 331 on the two tube sheets 33. The heat exchanger 30 is provided with a steam inlet pipe 35, and the steam inlet pipe 35 is used to pass high-temperature hot steam into the heat exchanger 30. The heat exchanger 30 is also provided with a condensate outlet pipe 36, and the condensate outlet pipe 36 is used to discharge the condensate generated after the high-temperature hot steam heat exchange. Specifically, the steam inlet pipe 35 is arranged at the top of the heat exchanger 30, and the condensate outlet pipe 36 is arranged at the bottom of the heat exchanger 30. When in use, the mixture transported into the heat exchanger 30 through the third transport pipe 21 is divided into a plurality of connecting pipes 34, and the mixture is fully contacted with the high-temperature hot steam introduced through the steam inlet pipe 35 in the plurality of connecting pipes 34, and the heat exchange is sufficient. A temperature sensor 37 is also installed in the heat exchanger 30, and the temperature sensor 37 can detect the temperature of the mixture, so as to heat the mixture to a suitable temperature.

[0028] like Figure 1 As shown, a fourth delivery pipe 31 is provided between the heat exchanger 30 and the distillation tower 40. The fourth delivery pipe 31 is connected to the outlet of the heat exchanger 30. The mixture after heat exchange in the heat exchanger 30 is delivered into the distillation tower 40 through the fourth delivery pipe 31. According to the different boiling points of benzene, toluene and xylene, their separation can be achieved by controlling the temperature. Benzene, toluene and xylene can be obtained by distilling the mixture in the distillation tower 40.

[0029] like Figure 1 As shown, a fifth delivery pipe 41 is provided between the distillation tower 40 and the condenser 50, and both ends of the fifth delivery pipe 41 are respectively connected to the distillation tower 40 and the condenser 50. When the distillation tower 40 is working, at different specific temperatures, evaporated benzene, toluene or xylene in the mixture is transported into the condenser 50 through the fifth delivery pipe 41 for condensation treatment. Under the condensation action of the condenser 50, the high-temperature steam is condensed.

[0030] like Figure 1As shown, a sixth delivery pipe 51 is provided between the condenser 50 and the condensate storage tank 60, and both ends of the sixth delivery pipe 51 are respectively connected to the condenser 50 and the condensate storage tank 60. The condensate condensed by the condenser 50 is transported into the condensate storage tank 60 through the sixth delivery pipe 51. By collecting the evaporated liquids at different temperatures, benzene, toluene and xylene with higher purity can be obtained, thereby realizing the separation and purification of crude benzene after hydrogenation.

[0031] like Figure 2 As shown, two groups of thermal insulation components 32 are arranged outside the fourth delivery pipe 31, and the fourth delivery pipe 31 is arranged between the two groups of thermal insulation components 32. The thermal insulation component 32 includes a pipe clamp 321, a first thermal insulation layer 322 arranged on the pipe clamp 321, and a second thermal insulation layer 323. The first thermal insulation layer 322 is arranged on the inner surface of the pipe clamp 321, and the second thermal insulation layer 323 is arranged on the first thermal insulation layer 322. The two pipe clamps 321 in the two groups of thermal insulation components 32 are detachable by bolts. The fourth delivery pipe 31 is accommodated between the two second insulation layers 323. Specifically, the first insulation layer 322 can be made of polystyrene foam, polyurethane foam, etc., and the second insulation layer 323 can be made of polyurethane rigid foam, etc. By arranging a thermal insulation component 32 outside the fourth delivery pipe 31, the hot mixture that has undergone heat exchange in the fourth delivery pipe 31 can be insulated to avoid heat loss in the mixture, so that the temperature of the mixture entering the distillation tower 40 is higher, which is convenient for subsequent distillation treatment.

[0032] The crude benzene hydrogenation refining and purification system provided by the utility model is that the reaction product obtained after the crude benzene is hydrogenated is transported into the stabilization tower 10 through the first delivery pipe 11 to remove the acidic gas, and the mixture obtained by extraction and separation in the extraction tower 20 is transported into the heat exchanger 30 through the third delivery pipe 21, and the mixture is heat exchanged and heated in the heat exchanger 30, and the mixture is preheated by heat exchange between the high-temperature hot steam and the mixture, so that the temperature of the mixture is increased, which is convenient for subsequent distillation operation. The mixture is fully in contact with the high-temperature hot steam in the multiple connecting pipes 34 in the heat exchanger 30 to improve the heat exchange efficiency; by arranging the heat insulation component 32 outside the fourth delivery pipe 31, the heat-containing mixture in the fourth delivery pipe 31 after heat exchange can be insulated to avoid heat loss in the mixture, improve the efficiency of distillation treatment, and by collecting the liquid evaporated at different temperatures, benzene, toluene and xylene with higher purity can be obtained, so as to achieve separation and purification after the crude benzene is hydrogenated.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, it can be a mechanical connection, it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] It should be understood that the terms "length", "width", "up", "down", "front and back", "left and right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0035] The above is based on the ideal embodiment of the utility model. Through the above description, relevant staff can make various changes and modifications without departing from the scope of the utility model. The technical scope of this utility model is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A crude benzene hydrogenation refining and purification system, characterized in that: The invention comprises a stabilization tower, an extraction tower, a heat exchanger, a distillation tower, a condenser and a condensate storage tank, wherein the stabilization tower is connected to the extraction tower, the extraction tower is connected to the heat exchanger, the heat exchanger is connected to the distillation tower, the distillation tower is connected to the condenser, the condenser is connected to the condensate storage tank, a fourth delivery pipe is arranged between the heat exchanger and the distillation tower, the fourth delivery pipe is connected to the outlet of the heat exchanger, two groups of thermal insulation components are arranged outside the fourth delivery pipe, the fourth delivery pipe is arranged between the two groups of thermal insulation components, the thermal insulation component comprises a pipe clamp, a first thermal insulation layer arranged on the pipe clamp , and a second thermal insulation layer, the first thermal insulation layer is arranged on the inner surface of the pipe clamp, the second thermal insulation layer is arranged on the first thermal insulation layer, the two pipe clamps in the two groups of the thermal insulation components are detachably connected, the fourth delivery pipe is accommodated between the two second thermal insulation layers, two tube sheets are arranged in the heat exchanger, the tube sheets are symmetrically arranged at both ends of the heat exchanger, the tube sheets are arranged vertically, a plurality of through holes are opened on the tube sheets, the through holes on the two tube sheets are arranged one by one, and connecting pipes are connected one by one between the through holes on the two tube sheets, a temperature sensor is also installed in the heat exchanger, and a steam inlet pipe and a condensate outlet pipe are arranged on the heat exchanger.

2. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: The stabilizing tower is provided with a first delivery pipe, and the first delivery pipe is communicated with the interior of the stabilizing tower.

3. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: A second delivery pipe is arranged between the stabilization tower and the extraction tower, and two ends of the second delivery pipe are respectively connected with the stabilization tower and the extraction tower.

4. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: A third delivery pipe is provided between the extraction tower and the heat exchanger, and the third delivery pipe is communicated with the inlet of the heat exchanger.

5. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: A fifth delivery pipe is provided between the distillation tower and the condenser, and both ends of the fifth delivery pipe are respectively connected to the distillation tower and the condenser.

6. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: A sixth delivery pipe is provided between the condenser and the condensate storage tank, and two ends of the sixth delivery pipe are respectively connected to the condenser and the condensate storage tank.

7. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: The two pipe clamps in the two groups of thermal insulation components are detachably connected by bolts.

8. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: A temperature sensor is also installed in the heat exchanger.

9. A crude benzene hydrorefining and purification system according to claim 1, characterized in that: The steam inlet pipe is arranged at the top of the heat exchanger, and the condensate outlet pipe is arranged at the bottom of the heat exchanger.

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