Heat pump rectification system suitable for working medium with phase change
By introducing a heat pump distillation system into the fractionation tower of an oil refinery, the low-temperature heat at the top of the tower is recovered and recycled by increasing the temperature and pressure. This solves the problem of unrecovered waste heat from the gaseous material at the top of the tower, achieving efficient energy conversion and cost reduction.
Patent Information
- Application Number
- CN202423290496.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2034-12-31
AI Technical Summary
During the operation of distillation towers, the low-temperature waste heat of the gaseous material at the top of the tower is not effectively recovered, resulting in energy waste. At the same time, the heating cost of high-temperature materials is high.
A heat pump distillation system suitable for phase change working fluids is adopted. After the compressor heats and pressurizes the distillate, the heat is released in the condenser to recover the low-temperature heat at the top of the column. The heat is then depressurized through a throttling valve and returned to the condensing system, thus realizing the recycling of heat.
It saves on the consumption of low-pressure steam and circulating water, reduces operating costs, and improves energy efficiency.
Smart Images
Figure CN223874464U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to rectification technical field, concretely is a kind of heat pump rectification system suitable for phase change working substance occurs. BACKGROUND
[0002] Oil refining enterprise each process device fractionating column operating process usually sets tower top condensing system, tower top gas phase material because heat quality is lower, cannot directly utilize, and is cooled by air cooling, circulating water or other medium, and a large amount of heat is directly taken away in cooling process, waste heat is not recycled, causing the waste of energy in large quantities.Meanwhile, there are many materials needing heating in oil refining enterprise each process device, these materials usually use steam and other high-temperature heat source to heat, and heating load is large, and device operating cost is higher. UTILITY MODEL CONTENT
[0003] The utility model is to provide a kind of heat pump rectification system suitable for phase change working substance occurs, to solve the problem raised in the above background technique.
[0004] To achieve the above object, the utility model provides the following technical scheme:
[0005] A kind of heat pump rectification system suitable for phase change working substance occurs, including fractionating column body, the fractionating column body one side is connected with fractionating column feed line, first connecting line and column bottom product line are connected in the bottom of fractionating column body, the other end of the first connecting line is connected with fractionating column bottom reboiler, the top of the fractionating column bottom reboiler is connected with second connecting line, the other end of the second connecting line is connected with fractionating column body, low-pressure steam import is provided on fractionating column bottom reboiler, is connected with condensate discharge line simultaneously, third connecting line is connected in the top of fractionating column body, the other end of the third connecting line is connected with fractionating column top cooler, fourth connecting line is connected in the side of fractionating column top cooler, the other end of the fourth connecting line is connected with fractionating column top reflux tank, the top of the fractionating column top reflux tank is connected with incondensable gas discharge line, the bottom of the fractionating column top reflux tank is connected with fifth connecting line, the other end of the fifth connecting line is connected with fractionating column top reflux pump, sixth connecting line is connected on fractionating column top reflux pump, the other end of the sixth connecting line is connected with fractionating column body, column top product line is connected on the sixth connecting line;
[0006] The third connecting line is connected with a flow regulating valve, the flow regulating valve is connected with a seventh connecting line, the other end of the seventh connecting line is connected with a compressor suction tank, the top of the compressor suction tank is connected with an eighth connecting line, the other end of the eighth connecting line is connected with a compressor, the outlet of the compressor is connected with a ninth connecting line, the other end of the ninth connecting line is connected with a new condenser, the new condenser is connected with a hot material return line and a tenth connecting line, a eleventh connecting line is connected with one side of the new condenser, the other end of the eleventh connecting line is connected with a throttling valve, the throttling valve is connected with a twelfth connecting line, and the other end of the twelfth connecting line is connected with the third connecting line.
[0007] Compared with the prior art, the utility model has the advantages that:
[0008] 1. The utility model discloses a heat pump rectification system, which solves the problems of low heat energy recovery rate, high unit investment cost and huge waste of low-temperature heat energy caused by circulating water / air cooler cooling in the prior art.
[0009] 2. The heat pump rectification system is suitable for the working conditions of large molecular weight, complex heat source composition, large pressure ratio, wide distillation, many impurities and easily compressible liquid components, adopts a closed compression circulation system, and realizes efficient energy conversion. BRIEF DESCRIPTION OF DRAWINGS
[0010] The utility model will be further explained in detail in connection with the embodiments in the drawings, but does not constitute any limitation to the utility model.
[0011] Figure 1 It is a flow diagram of a heat pump rectification system suitable for phase change working medium.
[0012] In the drawing: 1, fractionating tower body;2, fractionating tower bottom reboiler;3, fractionating tower top cooler;4, fractionating tower top reflux tank;5, fractionating tower top reflux pump;6, fractionating tower feed line;7, first connecting line;8, second connecting line;9, third connecting line;10, fourth connecting line;11, fifth connecting line;12, sixth connecting line;13, tower top product line;14, non-condensable gas discharge line;15, low-pressure steam inlet;16, condensate discharge line;17, tower bottom product line;18, flow regulating valve;19, seventh connecting line;20, compressor suction tank;21, compressor;22, new condenser;23, throttling valve;24, twelfth connecting line;25, eighth connecting line;26, ninth connecting line;27, eleventh connecting line;28, tenth connecting line;29, hot material return line. DETAILED DESCRIPTION
[0013] The technical solutions of the patent will be further described in detail in combination with specific embodiments.
[0014] Please refer to Figure 1 A heat pump rectification system suitable for phase change working medium, comprising a fractionating tower body 1, a fractionating tower feed line 6 connected to one side of the fractionating tower body 1, a first connecting line 7 connected to the bottom of the fractionating tower body 1 and a tower bottom product line 17, another end of the first connecting line 7 being connected with a fractionating tower bottom reboiler 2, a second connecting line 8 being connected to the top of the fractionating tower bottom reboiler 2, another end of the second connecting line 8 being connected with the fractionating tower body 1, a low-pressure steam inlet 15 being arranged on the fractionating tower bottom reboiler 2, and a condensed water discharge line 16 being connected therewith, a third connecting line 9 being connected to the top of the fractionating tower body 1, another end of the third connecting line 9 being connected with a fractionating tower top cooler 3, a fourth connecting line 10 being connected to one side of the fractionating tower top cooler 3, another end of the fourth connecting line 10 being connected with a fractionating tower top reflux tank 4, the top of the fractionating tower top reflux tank 4 being connected with a non-condensable gas discharge line 14, the bottom of the fractionating tower top reflux tank 4 being connected with a fifth connecting line 11, another end of the fifth connecting line 11 being connected with a fractionating tower top reflux pump 5, a sixth connecting line 12 being connected to the fractionating tower top reflux pump 5, another end of the sixth connecting line 12 being connected with the fractionating tower body 1, and a tower top product line 13 being connected to the sixth connecting line 12, a flow regulating valve 18 being connected to the third connecting line 9, a seventh connecting line 19 being connected to the flow regulating valve 18, another end of the seventh connecting line 19 being connected with a compressor suction tank 20, an eighth connecting line 25 being connected to the top of the compressor suction tank 20, another end of the eighth connecting line 25 being connected with a compressor 21, the outlet of the compressor 21 being connected with a ninth connecting line 26, another end of the ninth connecting line 26 being connected with a new condenser 22, the new condenser 22 being connected with a hot material return line 29 and a tenth connecting line 28, an eleventh connecting line 27 being connected to one side of the new condenser 22, another end of the eleventh connecting line 27 being connected with a throttling valve 23, a twelfth connecting line 24 being connected to the throttling valve 23, and another end of the twelfth connecting line 24 being connected with the third connecting line 9.
[0015] A crude styrene column of a styrene plant in a certain petrochemical enterprise consumes 0.04 MPa g steam about 18.7 t / h, the gas phase at the top of the column is about 133.8 t / h, the pressure is 8 Kpa A, and the temperature is 63.06℃. The temperature at the top is low and the mixture is complex in composition, which is difficult to be directly utilized. At present, it is directly cooled by circulating water, and the temperature after cooling is about 42℃, and the circulating water consumption is about 1900 t / h.
[0016] The gas phase of the crude styrene column top enters the compressor 21 of the newly added heat pump rectification system suitable for phase change working medium for compression, and after the low-grade heat of the column top is upgraded by the compressor 21, it enters the newly added heat exchanger for condensation and heat release, replacing 18.7 t / h of steam. The condensed working medium returns to the column top condensation system through the pressure reducing valve 23 to complete the heat recovery cycle.
[0017] After the implementation of the heat pump rectification system suitable for phase change working medium, 18.7 t / h of low-pressure steam can be saved, and 1370 t / h of column top circulating water consumption can be saved. According to 8400 hours of annual operation time, the annual energy saving benefit is 15 million yuan. The patent technology has good economic and social benefits.
[0018] Process flow:
[0019] Step one: The material from the upstream device enters the fractionating tower body 1 through the fractionating tower feed line 6, the gas phase material is sent to the fractionating tower top cooler 3 from the tower top of the fractionating tower body 1 through the third connecting line 9, the cooled material enters the fractionating tower top reflux tank 4 through the fourth connecting line 10, and the non-condensable gas is sent to the non-condensable gas pipe network through the non-condensable gas discharge line 14;
[0020] Step two: The condensed material is pumped out from the bottom of the fractionating tower top reflux tank 4, pressurized by the fractionating tower top reflux pump 5 through the fifth connecting line 11, part of which returns to the upper part of the fractionating tower body 1 as reflux through the sixth connecting line 12, and part of which is sent out as a product or to a downstream device through the tower top product line 13;
[0021] Step three: The material at the bottom of the fractionating tower enters the fractionating tower bottom reboiler 2 through the first connecting line 7 for heating, and the heated material returns to the fractionating tower body 1 through the second connecting line 8;
[0022] Step four: The low-pressure steam is used as the heat source of the fractionating tower bottom reboiler 2, enters the fractionating tower bottom reboiler 2 through the low-pressure steam inlet 15, and the condensed water after heat exchange returns to the condensed water pipe network through the condensed water discharge line 16. The material at the bottom of the tower is sent out as a product or to a downstream device through the tower bottom product line 17.
[0023] Step five: The gas phase material at the top of the fractionating tower body 1 enters the flow regulating valve 18 through the third connecting line 9, and then enters the compressor suction tank 20 through the seventh connecting line 19. The gas phase material enters the compressor 21 for compression through the eighth connecting line 25 at the top of the compressor suction tank 20;
[0024] Step six: The gas phase material after temperature and pressure rise by the compressor 21 is sent to the newly added condenser 22 for condensation and heat release to provide heat for the heat sink or generate low-temperature hot water;
[0025] Step seven: the cold process material enters the newly added condenser 22 through the tenth connecting line 28 to take heat, and the heated material after taking heat returns to the original process device through the hot material return line 29;
[0026] Step eight: the condensed material is sent to the throttle valve 23 through the eleventh connecting line 27, is depressurized through the throttle valve 23, and is returned to the fractionating tower top cooler 3 through the twelfth connecting line 24 to complete the heat recovery cycle.
[0027] The above-mentioned embodiments are preferred embodiments of the present application, which are only used to facilitate the description of the present application and do not limit the present application in any form. Any person with ordinary knowledge in the art can make equivalent embodiments by making partial changes or modifications within the scope of the technical features disclosed in the present application without departing from the technical features of the present application, and the equivalent embodiments still belong to the scope of the technical features of the present application.
Claims
1. A heat pump rectifying system suitable for phase change working medium, comprising a rectifying tower body (1), a rectifying tower feed line (6) is connected to one side of the rectifying tower body (1), a first connecting line (7) is connected to the bottom of the rectifying tower body (1), and a tower bottom product line (17) is connected to the other end of the first connecting line (7), a rectifying tower bottom reboiler (2) is connected to the other end of the first connecting line (7), a second connecting line (8) is connected to the top of the rectifying tower bottom reboiler (2), and the other end of the second connecting line (8) is connected with the rectifying tower body (1), a low-pressure steam inlet (15) is arranged on the rectifying tower bottom reboiler (2), and a condensed water discharge line (16) is connected, a third connecting line (9) is connected to the top of the rectifying tower body (1), a rectifying tower top cooler (3) is connected to the other end of the third connecting line (9), a fourth connecting line (10) is connected to one side of the rectifying tower top cooler (3), a rectifying tower top reflux tank (4) is connected to the other end of the fourth connecting line (10), a non-condensable gas discharge line (14) is connected to the top of the rectifying tower top reflux tank (4), a fifth connecting line (11) is connected to the bottom of the rectifying tower top reflux tank (4), a rectifying tower top reflux pump (5) is connected to the other end of the fifth connecting line (11), a sixth connecting line (12) is connected to the rectifying tower top reflux pump (5), and the other end of the sixth connecting line (12) is connected with the rectifying tower body (1), and a tower top product line (13) is connected to the sixth connecting line (12); characterized in that A flow regulating valve (18) is connected to the third connecting line (9), a seventh connecting line (19) is connected to the flow regulating valve (18), a compressor suction tank (20) is connected to the other end of the seventh connecting line (19), an eighth connecting line (25) is connected to the inlet of the compressor suction tank (20), a compressor (21) is connected to the other end of the eighth connecting line (25), a ninth connecting line (26) is connected to the outlet of the compressor (21), a new condenser (22) is connected to the other end of the ninth connecting line (26), the new condenser (22) is connected with a hot material return line (29) and a tenth connecting line (28), an eleventh connecting line (27) is connected to one side of the new condenser (22), a throttling valve (23) is connected to the other end of the eleventh connecting line (27), a twelfth connecting line (24) is connected to the throttling valve (23), and the other end of the twelfth connecting line (24) is connected with the third connecting line (9).