Steam system for producing dimethyl carbonate
By introducing the eighth reboiler and new feeder into the steam system produced by dimethyl carbonate, the steam flow path is optimized, and the problems of large steam usage and poor heat exchange order are solved, and steam energy conservation and energy are achieved Make full use of the
Patent Information
- Application Number
- CN202421119267.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-22
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-05-22
AI Technical Summary
In the production process of dimethyl carbonate, the steam is used in large quantities and the heat exchange sequence is poor, resulting in a large amount of steam waste and energy waste.
By introducing the eighth reboiler and a new feeder into the steam system, the flow path of the steam is optimized, so that the steam can be heat exchanged multiple times between the eighth reboiler and the third reboiler A, and the steam loss is reduced. And increase the raw material temperature through a new feeder and reduce the steam usage of the T4 reboiler.
It effectively reduces steam loss and energy consumption, improves steam utilization, saves steam volume, and realizes full utilization of energy.
Smart Images
Figure CN222325135U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of machinery, in particular to the technical field of mechanical parts, and specifically refers to a steam system for producing dimethyl carbonate. Background Art
[0002] In the process of producing dimethyl carbonate, T1, T2, T3, T4, T5, T6 and T7 are mainly used. T1, T2, T3, T4, T5, T6 and T7 are respectively a reaction distillation tower, a distillation separation tower, a methanol separation tower, a pressure distillation tower, a negative pressure distillation tower, a negative pressure distillation tower and an atmospheric distillation tower. Among them, T4 is connected with a fourth reboiler A and a fourth reboiler B arranged in parallel, and T4 is connected with a first-stage feeder, a second-stage feeder and a third-stage feeder arranged in series. T4 is connected with the third-stage feeder, and T3 is also connected with a third reboiler A, a third reboiler B and a third reboiler C arranged in parallel. T5, T6 and T7 are respectively connected with a fifth reboiler, a sixth reboiler and a seventh reboiler.
[0003] At present, in the use of steam, the steam discharged from the fourth reboiler A and the fourth reboiler B enters the third reboiler A, and the steam in the fifth reboiler, the sixth reboiler and the seventh reboiler enters the third reboiler B. The steam from the third reboiler A and the third reboiler B enters the first-level feeder for heat exchange as a heat source, the film steam and the steam from the second reboiler enter the second-level feeder, the steam in the incinerator enters the third-level feeder, and then the steam in the first-level feeder, the second-level feeder and the third-level feeder enter the hot water tank. Part of the steam composed of materials coming out of T4 enters the first reboiler for heating, and the other part enters the third reboiler C for heat exchange. Finally, the steam in the third reboiler C and the first reboiler returns to the T4 reflux tank and then enters T4 as material again.
[0004] However, the current steam consumption is large and the steam heat exchange sequence is poor, resulting in a large amount of steam waste, thereby causing a waste of energy. Utility Model Content
[0005] The utility model aims at the deficiencies of the prior art and provides a steam system for producing dimethyl carbonate, which can reasonably use steam, reduce the waste of steam volume and steam energy, and save energy.
[0006] The utility model is realized by the following technical scheme: a steam system for producing dimethyl carbonate, comprising a fourth total reboiler and a third reboiler A connected by a steam pipeline, an eighth reboiler B located between the fourth total reboiler and the third reboiler A is further arranged on the steam pipeline, the eighth reboiler B is connected to T8, and the steam after heat exchange from the fourth total reboiler enters the eighth reboiler B for heat exchange and then enters the third reboiler A.
[0007] When the utility model is in use, steam at 230°C and a flow rate of 34 t / h enters the fourth total reboiler and becomes steam at 180°C, the steam at 180°C enters the eighth reboiler B and becomes steam at 123°C, the steam at 123°C enters the third reboiler A and becomes steam at 77°C. The eighth reboiler B is provided to facilitate heat exchange with the steam at 180°C, while reducing the need for additional steam to exchange heat with the eighth reboiler B, thereby reducing steam loss.
[0008] Preferably, the fourth total reboiler is also connected to the seventh reboiler and the secondary feeder in sequence through pipelines, and the secondary feeder is connected to the steam inlet of the third reboiler A through a pipeline.
[0009] When this preferred solution is in use, the 180°C steam enters the seventh reboiler and becomes 160°C steam, the 160°C steam enters the secondary feeder and becomes 117°C steam, the 117°C steam also enters the third reboiler A, thereby reducing the additional steam for heat exchange with the seventh reboiler and the secondary feeder, thereby reducing the steam loss.
[0010] Preferably, the fifth reboiler of T5 and the sixth reboiler of T6 are also connected to the steam inlet of the third reboiler A through a pipeline.
[0011] When this preferred scheme is in use, since the temperature of the steam after heat exchange in the fifth reboiler and the sixth reboiler is 123°C, there will be serious heat waste if it only exchanges heat with the third reboiler B. Therefore, in order to give full play to the temperature of the steam after heat exchange in the fifth reboiler and the sixth reboiler, the steam from the fifth reboiler and the sixth reboiler is allowed to enter the third reboiler A.
[0012] Preferably, the second reboiler of T2 is connected to a three-stage feeder via a pipeline, and the three-stage feeder is connected to the steam inlet of the third reboiler A via a pipeline.
[0013] When this preferred solution is in use, the steam after heat exchange from the tertiary feeder is 125°C, and this part of the steam is also used as a heat source to exchange heat with the third reboiler A. Compared with directly entering the hot water tank, the amount of steam is saved and the steam is fully utilized.
[0014] Preferably, the steam outlet of the third reboiler A is connected to the primary feeder through a pipeline, and the steam outlet of the primary feeder is connected to a hot water tank.
[0015] This preferred solution fully utilizes the steam after heat exchange from the third reboiler A.
[0016] Preferably, a new feeder is connected in series between the primary feeder and the secondary feeder.
[0017] When this preferred solution is in use, the current feeder increases the temperature of the raw materials to a maximum of 95°C. After adding the new feeder, the maximum temperature can reach 100°C. After the temperature is increased, the amount of 2.5MPa steam in the T4 reboiler can be reduced, thereby achieving the purpose of energy saving and consumption reduction.
[0018] Preferably, the material steam of T4 is connected to the new feeder and the eighth reboiler A arranged in parallel through a pipeline, the eighth reboiler A is connected to T8, and the new feeder and the eighth reboiler A are both connected to the third reboiler C of T3 through a pipeline.
[0019] This preferred solution connects the material steam of T4 with the new feeder and the eighth reboiler A, thereby saving the use of other steam.
[0020] Preferably, the material steam of T3 is connected in series with a heat pump and the third reboiler B of T3 through a pipeline.
[0021] In this preferred solution, since the fifth, sixth and seventh reboilers no longer provide steam for heat exchange with the third reboiler B, the material steam of T3 is heated again and then heat exchanged with the third reboiler B, thereby fully utilizing the material steam of T3.
[0022] The beneficial effects of the utility model are as follows: 230°C, 34t / h steam enters the fourth total reboiler and becomes 180°C steam; 180°C steam enters the eighth reboiler B and becomes 123°C steam; 123°C steam enters the third reboiler A and becomes 77°C steam; the eighth reboiler B is provided to facilitate heat exchange with 180°C steam, while reducing the additional steam for heat exchange with the eighth reboiler B, thereby reducing steam loss; 180°C steam enters the seventh reboiler and becomes 160°C steam; The 160°C steam enters the secondary feeder and becomes 117°C steam, and the 117°C steam also enters the third reboiler A, thereby reducing the additional steam for heat exchange with the seventh reboiler and the secondary feeder, thereby reducing the loss of steam; since the steam after heat exchange in the fifth and sixth reboilers is 123°C, and there is a serious waste of heat if it only exchanges heat with the third reboiler B, in order to give full play to the temperature of the steam after heat exchange in the fifth and sixth reboilers, the steam from the fifth and sixth reboilers enters the third reboiler A. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a schematic diagram of the structure of the utility model;
[0024] Figure 2 It is a schematic diagram of the steam flow of the third reboiler A;
[0025] Figure 3 It is the schematic diagram of material steam flow of T4;
[0026] Figure 4 The material flow diagram of T3 is as follows:
[0027] Figure 5 It is a schematic diagram of the prior art;
[0028] As shown in the figure:
[0029] 1. T1, 3. T3, 4. T4, 5. fifth reboiler, 6. sixth reboiler, 7. seventh reboiler, 9. reflux tank, 10. hot water tank, 11. first reboiler, 21. second reboiler, 31. third reboiler A, 32. third reboiler B, 33. third reboiler C, 34. heat pump, 35. evaporative cooling, 41. fourth reboiler A, 42. fourth reboiler B, 43. new feeder, 44. first-stage feeder, 45. second-stage feeder, 46. third-stage feeder, 81. eighth reboiler A, 82. eighth reboiler B. DETAILED DESCRIPTION
[0030] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.
[0031] See attached Figure 1-3 The utility model discloses a steam system for producing dimethyl carbonate. The system is improved on the existing basis. In the process of producing dimethyl carbonate, T1, T2, T3, T4, T5, T6 and T7 are mainly used, wherein T4 is connected with a fourth total reboiler, the fourth total reboiler comprises a fourth reboiler A41 and a fourth reboiler B42 which are arranged in parallel, and T4 is connected with a first-stage feeder 44, a second-stage feeder 45 and a third-stage feeder 46 which are arranged in series, T4 is connected with the third-stage feeder 46, T3 is also connected with a third reboiler A31, a third reboiler B32 and a third reboiler C33 which are arranged in parallel, and T5, T6 and T7 are respectively connected with a fifth reboiler 5, a sixth reboiler 6 and a seventh reboiler 7.
[0032] At present, in the use of steam, the steam discharged from the fourth reboiler A and the fourth reboiler B enters the third reboiler A, and the steam in the fifth reboiler 5, the sixth reboiler 6, and the seventh reboiler 7 enters the third reboiler B. The steam from the third reboiler A and the third reboiler B enters the primary feeder 44 as a heat source for heat exchange, the film steam and the steam from the second reboiler 21 enter the secondary feeder 45, and the steam in the incinerator enters the tertiary feeder 46. Subsequently, the steam in the primary feeder 44, the secondary feeder 45, and the tertiary feeder 46 enters the hot water tank 10. A part of the steam composed of materials coming out of T4 enters the first reboiler 11 for heating, and the other part enters the third reboiler C for heat exchange. Finally, the steam in the third reboiler C and the first reboiler 11 returns to the T4 reflux tank 9, and then enters T4 as material again.
[0033] In this system, T8 and a new feeder 43 are newly added, T8 is connected to the eighth reboiler A and the eighth reboiler B arranged in parallel, and the new feeder 43 is connected in series between the secondary feeder 45 and the primary feeder 44;
[0034] An eighth reboiler B82 is provided between the fourth total reboiler and the third reboiler A. The eighth reboiler B is connected to T8. The steam after heat exchange from the fourth total reboiler enters the eighth reboiler B for heat exchange and then enters the third reboiler A31.
[0035] The fourth total reboiler is also connected to the seventh reboiler 7 and the secondary feeder 45 in sequence through pipelines, and the secondary feeder 45 is connected to the steam inlet of the third reboiler A through a pipeline.
[0036] The fifth reboiler 5 of T5 and the sixth reboiler 6 of T6 are also connected to the steam inlet of the third reboiler A through pipelines.
[0037] The second reboiler 21 of T2 is connected to a tertiary feeder 46 via a pipeline, and the tertiary feeder 46 is connected to the steam inlet of the third reboiler A via a pipeline.
[0038] The steam outlet of the third reboiler A is connected to the primary feeder 44 through a pipeline, and the steam outlet of the primary feeder 44 is connected to the hot water tank 10 .
[0039] The material steam of T4 is connected to the new feeder 43 and the eighth reboiler A arranged in parallel through a pipeline, the eighth reboiler A is connected to T8, and the new feeder 43 and the eighth reboiler A are both connected to the third reboiler C of T3 through a pipeline.
[0040] The material steam of T3 is connected in series with a heat pump 34 and the third reboiler B32 of T3 through a pipeline.
[0041] When the utility model is in use, the steam at 230°C enters the fourth reboiler A and the fourth reboiler B and becomes the steam at 180°C. Then this part of the steam is split and enters the eighth reboiler B and becomes the steam at 123°C. The steam at 123°C enters the third reboiler A. At the same time, the steam at 123°C in the fifth reboiler 5 and the sixth reboiler 6 also enters the third reboiler A.
[0042] Another part of the 180°C steam enters the seventh reboiler 7 and becomes 160°C steam, and the 160°C steam enters the secondary feeder 45 and becomes 117°C steam;
[0043] The 184°C steam enters the second reboiler 21 and becomes 181°C steam, and the 181°C steam enters the third-stage feeder 46 and becomes 125°C steam;
[0044] At the same time, the steam at 125°C after entering the tertiary feeder 46 and the steam at 117°C after entering the secondary feeder 45 also enter the third reboiler A, thereby heating the third reboiler A. The steam coming out of the third reboiler A becomes 77°C, and the 77°C steam enters the primary feeder 44, finally becomes 70°C, and then enters the hot water tank 10 at normal pressure.
[0045] The material steam of T4 is divided into four parts. The first part enters the first reboiler 11, the second part enters the third reboiler C, the third part enters the eighth reboiler A, and the fourth part enters the new feeder 43. The steam coming out of the new feeder 43 and the steam coming out of the eighth reboiler A finally enter the third reboiler C. The steam in the third reboiler C and the first reboiler 11 returns to the T4 reflux drum 9 and then enters T4 as material again.
[0046] The material steam of T3 is divided into two parts. The first part enters the heat pump 34 for heating, and then enters the third reboiler B. The material steam after heat exchange in the third reboiler B is refluxed or extracted as raw material. The second part is directly evaporated and cooled 35, and then refluxed or extracted as raw material.
[0047] In particular, T1, T2, T3, T4, T5, T6, T7, and T8 are respectively a reactive distillation tower, a distillation separation tower, a methanol separation tower, a pressure distillation tower, a negative pressure distillation tower, a negative pressure distillation tower, a normal pressure distillation tower, and a normal pressure distillation tower.
[0048] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved by or by adopting the existing technology, which will not be repeated here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not deviate from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.
Claims
1. A steam system for producing dimethyl carbonate, comprising a fourth total reboiler and a third reboiler A (31) connected by a steam pipeline, characterized in that: The steam pipeline is further provided with an eighth reboiler B (82) located between the fourth total reboiler and the third reboiler A (31). The eighth reboiler B (82) is connected to T8. The steam after heat exchange from the fourth total reboiler enters the eighth reboiler B for heat exchange and then enters the third reboiler A.
2. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: The fourth total reboiler is also connected to the seventh reboiler (7) and the secondary feeder (45) in sequence through pipelines, and the secondary feeder (45) is connected to the steam inlet of the third reboiler A (31) through a pipeline.
3. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: The fifth reboiler (5) of T5 and the sixth reboiler (6) of T6 are also connected to the steam inlet of the third reboiler A (31) through a pipeline.
4. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: The second reboiler (21) of T2 is connected to a tertiary feeder (46) via a pipeline, and the tertiary feeder (46) is connected to the steam inlet of the third reboiler A (31) via a pipeline.
5. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: The steam outlet of the third reboiler A (31) is connected to the primary feeder (44) through a pipeline, and the steam outlet of the primary feeder (44) is connected to the hot water tank (10).
6. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: A new feeder (43) is also connected in series between the primary feeder (44) and the secondary feeder (45).
7. The steam system for producing dimethyl carbonate according to claim 6, characterized in that: The material steam of T4 is connected to the new feeder (43) and the eighth reboiler A (81) arranged in parallel through a pipeline. The eighth reboiler A is connected to T8. The new feeder (43) and the eighth reboiler A are both connected to the third reboiler C (33) of T3 through a pipeline.
8. The steam system for producing dimethyl carbonate according to claim 1, characterized in that: The material steam of T3 is connected in series with a heat pump (34) and the third reboiler B (32) of T3 via a pipeline.