Residual heat utilization system and ethoxylation reaction device

Abstract

The application discloses a waste heat utilization system and an ethoxylation reaction device, wherein the waste heat utilization system comprises a reaction kettle heat exchanger, a circulating pump, a first valve body, a pretreatment heat exchanger and a second valve body. The reaction in the reaction kettle releases heat, the heat exchange medium in the reaction kettle heat exchanger absorbs the heat and is heated, and the heat exchange medium flowing out of the reaction kettle heat exchanger at least partially enters the pretreatment heat exchanger through cooperation between the first valve body and the second valve body, so that the initiator in the pretreatment kettle is heated through the pretreatment heat exchanger. The reaction waste heat generated in the production process of the ethoxylation reaction device is fully utilized, the utilization efficiency of the reaction waste heat in the production process is improved, and the production energy cost is reduced. Meanwhile, the opening degree of the first valve body is adjusted according to the requirement, the flow of the heat exchange medium passing through the pretreatment heat exchanger is controlled, and precise temperature control of the initiator in the pretreatment kettle is realized.

Description

Technical Field

[0001] This application relates to the field of ethoxylation reaction technology, and in particular to a waste heat utilization system and an ethoxylation reaction apparatus having a waste heat utilization system. Background Technology

[0002] Currently, the ethoxylation reaction requires steam to heat the hot water system in the early stages. The system heats the initiator to the initial reaction temperature of 120 degrees Celsius before adding ethylene oxide to initiate the reaction, which releases heat. When using steam to heat the initiator in the pretreatment process, the steam consumption per batch is 1.5-2 tons, and the daily production requirement is between 4.5-6 tons, resulting in high steam energy consumption during production. Furthermore, the heat released during the ethylene oxide reaction is not utilized in a timely manner, wasting significant energy resources and leading to excessively high production costs. Utility Model Content

[0003] To solve the above-mentioned technical problems, or at least partially solve them, this application provides the following technical solutions: In a first aspect, embodiments of this application provide a waste heat recovery system for an ethoxylation reaction apparatus, comprising: a reactor heat exchanger configured to absorb heat from the reactor; a circulating pump, the outlet of which is connected to the inlet of the reactor heat exchanger via a first pipe, and the return port of which is connected to the outlet of the reactor heat exchanger via a second pipe; a first valve body disposed on the second pipe and configured to control the flow rate of the heat exchange medium in the second pipe; a third pipe, one port of which is connected to the second pipe located between the outlet and the first valve body, and the other port of which is connected to the second pipe located between the return port and the first valve body; a pretreatment heat exchanger disposed on the third pipe and configured to heat the initiator in the pretreatment reactor; and a second valve body disposed on the third pipe and configured to control the on / off state of the third pipe.

[0004] In some embodiments, the reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger; the small circulation heat exchanger and the large circulation heat exchanger are respectively connected to the circulation pump through two different second pipes; the first valve body is disposed on the second pipe connected to the small circulation heat exchanger; the third pipe is connected to the outlet of the small circulation heat exchanger.

[0005] In some embodiments, the waste heat recovery system further includes: a fourth conduit connecting two of the second conduits, one port of the fourth conduit being connected to the large circulation heat exchanger, and the other port of the fourth conduit being located between the second valve body and the small circulation heat exchanger; and a third valve body disposed on the fourth conduit and configured to control the flow rate of the heat exchange medium within the fourth conduit.

[0006] In some embodiments, the waste heat recovery system further includes: a first controller connected to the third valve body, the first controller being configured to control the opening and closing degree of the third valve body; and a first temperature sensor connected to the first controller, the first temperature sensor being configured to detect the temperature of the heat exchange medium entering the pretreatment heat exchanger and send a first temperature signal to the first controller.

[0007] In some embodiments, the reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger; the small circulation heat exchanger and the large circulation heat exchanger are respectively connected to the circulation pump through two different second pipes; the first valve body is disposed on the second pipe connected to the large circulation heat exchanger; the third pipe is connected to the outlet of the large circulation heat exchanger.

[0008] In some embodiments, the reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger; the second pipeline includes a first branch pipeline, a second branch pipeline, and a manifold pipeline; one end of the first branch pipeline is connected to the small circulation heat exchanger, and one end of the second branch pipeline is connected to the large circulation heat exchanger; one end of the manifold pipeline is connected to the circulation pump, and the other end of the manifold pipeline is connected to the other end of the first branch pipeline and the other end of the second branch pipeline, respectively; the first valve body is disposed on the manifold pipeline; and the third pipeline is connected in parallel with the manifold pipeline.

[0009] In some embodiments, the waste heat recovery system further includes: a second controller connected to the first valve body and configured to control the opening and closing degree of the first valve body; and a second temperature sensor connected to the second controller and configured to detect the temperature of the initiator in the pretreatment vessel and send a second temperature signal to the second controller.

[0010] In some embodiments, the second valve body is a three-way switching valve having a first valve port, a second valve port, and a third valve port. The first valve port is connected to the pretreatment heat exchanger, and the second valve port is connected to the reactor heat exchanger. The three-way switching valve is configured to switch the first valve port to be connected to the second valve port or the third valve port via a valve core. The waste heat utilization system further includes: a steam generating device, the steam outlet of which is connected to the third valve port; and a liquid return pipe, which connects the steam return port of the steam generating device to the pretreatment heat exchanger.

[0011] In some embodiments, the waste heat recovery system further includes: a third controller connected to the first valve body and the second valve body, the third controller being configured to control the switching between the valve ports of the second valve body and the opening and closing degree of the first valve body; and a third temperature sensor connected to the third controller, the third temperature sensor being configured to detect the temperature of the heat exchange medium at the outlet of the reactor heat exchanger and send a third temperature signal to the third controller.

[0012] Compared with existing technologies, the above technical solution has the following advantages: The reaction in the reactor releases heat. The heat exchange medium in the reactor heat exchanger absorbs this heat and rises in temperature. Then, through the cooperation between the first valve body and the second valve body, at least part of the heat exchange medium flowing out of the reactor heat exchanger enters the pretreatment heat exchanger to heat the initiator in the pretreatment reactor. This fully utilizes the waste heat generated during the ethoxylation reaction process, improves the utilization efficiency of waste heat during the production process, and thus reduces production energy costs.

[0013] Secondly, embodiments of this application provide an ethoxylation reaction apparatus, comprising: a pretreatment vessel configured to pretreat an initiator; a reaction vessel connected to the pretreatment vessel; and the aforementioned waste heat utilization system, wherein a heat exchanger for the reaction vessel of the waste heat utilization system is disposed on the reaction vessel, and a heat exchanger for the pretreatment vessel of the waste heat utilization system is disposed on the pretreatment vessel.

[0014] The ethoxylation reaction apparatus provided in this application embodiment has the same technical effect as the waste heat utilization system provided in the above embodiment, and will not be described again here. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic diagram of the structure of a first embodiment of a waste heat utilization system provided in some embodiments of this application; Figure 2 A structural block diagram of the first control section of a waste heat utilization system provided in some embodiments of this application; Figure 3 A schematic diagram of the structure of a second embodiment of the waste heat utilization system provided in some embodiments of this application; Figure 4 Structural block diagram of the second control section of a waste heat utilization system provided in some embodiments of this application; Figure 5 A schematic diagram of the structure of a third embodiment of the waste heat utilization system provided in some embodiments of this application; Figure 6 A schematic diagram of the structure of a fourth embodiment of the waste heat utilization system provided in some embodiments of this application; Figure 7 Structural block diagram of the third control section of a waste heat utilization system provided in some embodiments of this application; Figure 8 A schematic diagram of the structure of a fifth embodiment of the waste heat utilization system provided in some embodiments of this application; Figure 9 This is a schematic diagram of the sixth embodiment of the waste heat utilization system provided in some embodiments of this application.

[0017] The attached figures are labeled as follows: 10. Reactor heat exchanger; 11. Small circulation heat exchanger; 12. Large circulation heat exchanger; 20. Circulating pump; 30. First valve body; 40. Pretreatment heat exchanger; 50. Second valve body; 60. Third valve body; 71. First controller; 72. First temperature sensor; 81. Second controller; 82. Second temperature sensor; 91. Third controller; 92. Third temperature sensor; 100. Steam generating device. Detailed Implementation

[0018] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.

[0019] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit this application; the terms "comprising" and "having" and any variations thereof in the specification and the foregoing description of this application are intended to cover non-exclusive inclusion. The term "embodiment" as used in this application means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0020] The specific term "exemplary" used in this application means "serving as an example, embodiment, or illustration." Any embodiment illustrated as "exemplary" is not necessarily to be construed as superior or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0021] In the description of this application, the technical terms "first", "second", "third", etc. are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0022] In the description of this application, "multiple" means two or more (including two), unless otherwise expressly and specifically defined.

[0023] In the description of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, and other dimensions of various components in the embodiments of this application shown in the drawings, as well as the overall thickness, length, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0024] The technical solutions of the embodiments of this application are described in detail below with reference to the accompanying drawings. The technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0025] like Figures 1 to 9 As shown, the waste heat utilization system for an ethoxylation reaction apparatus provided in the first aspect of this application includes: a reactor heat exchanger 10, a circulating pump 20, a first valve body 30, a third pipeline, a pretreatment heat exchanger 40, and a second valve body 50.

[0026] The reactor heat exchanger 10 is configured to absorb heat from the reactor.

[0027] The outlet of the circulating pump 20 is connected to the inlet of the reactor heat exchanger 10 via a first pipe, and the return port of the circulating pump 20 is connected to the outlet of the reactor heat exchanger 10 via a second pipe. It is worth noting that the heat exchange medium needs to be cooled by a cooling system before returning to the circulating pump 20 to ensure it can reabsorb heat from the reactor. The cooling system is existing technology, and its specific structure, working principle, and possible control and spatial arrangement can be achieved using conventional methods in this field; therefore, further detailed descriptions are not provided here.

[0028] The first valve body 30 is disposed on the second pipeline. The first valve body 30 is configured to control the flow rate of the heat exchange medium in the second pipeline. Specifically, the amount of heat exchange medium passing through the first valve body 30 is controlled by adjusting the opening degree of the first valve body 30.

[0029] One port of the third pipe is connected to the second pipe located between the outlet and the first valve body 30, and the other port of the third pipe is connected to the second pipe located between the return port and the first valve body 30, that is, the third pipe is connected in parallel to the second pipe. In one embodiment of this application, the diameter of the second pipe is larger than the diameter of the third pipe.

[0030] The pretreatment heat exchanger 40 is installed on the third pipe and is configured to heat the initiator in the pretreatment vessel. Specifically, the pretreatment heat exchanger 40 is connected in parallel with the first valve body 30.

[0031] The second valve body 50 is installed on the third pipeline. The second valve body 50 is configured to control the opening and closing of the third pipeline. Specifically, the second valve body 50 is connected in series with the pretreatment heat exchanger 40 and then in parallel with the first valve body 30. The second valve body 50 includes two states: open and closed.

[0032] The waste heat utilization system provided in this application involves a heat exchange medium in the reactor heat exchanger 10 absorbing heat released from the reaction in the reactor and heating up. Through the cooperation between the second valve body 50 and the first valve body 30, at least a portion of the heat exchange medium flowing out of the reactor heat exchanger 10 enters the pretreatment heat exchanger 40 to heat the initiator in the pretreatment reactor. This fully utilizes the waste heat generated during the ethoxylation reaction process, improves the utilization efficiency of waste heat during production, and reduces production energy costs.

[0033] In addition, by adjusting the opening degree of the first valve body 30 as needed, the flow rate of the heat exchange medium through the second and third channels can be reasonably distributed, that is, the flow rate of the heat exchange medium through the pretreatment heat exchanger 40 can be controlled to achieve precise temperature control of the initiator in the pretreatment vessel. This avoids the situation where the flow rate of the heat exchange medium through the pretreatment heat exchanger 40 is too large, resulting in an excessively high temperature of the initiator in the pretreatment vessel, or the situation where the flow rate of the heat exchange medium through the pretreatment heat exchanger 40 is too small, resulting in the initiator in the pretreatment vessel not reaching the required temperature. Specifically, the opening degree of the first valve body 30 can be 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%. If the temperature of the initiator is low and rapid heating is required, the opening degree of the first valve body 30 is adjusted to 0, so that all the heat exchange medium passes through the pretreatment heat exchanger 40, so that the initiator can quickly reach the target temperature; the opening degree of the first valve body 30 is increased (e.g., 95% or 100%), so that a small portion of the heat exchange medium passes through the pretreatment heat exchanger 40, so that the initiator is maintained at the target temperature.

[0034] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the waste heat utilization system further includes a second controller 81 and a second temperature sensor 82.

[0035] The second controller 81 is connected to the first valve body 30 and is configured to control the opening and closing degree of the first valve body 30.

[0036] The second temperature sensor 82 is connected to the second controller 81. The second temperature sensor 82 is configured to detect the temperature of the initiator in the pretreatment vessel and send a second temperature signal to the second controller 81. When the second controller 81 determines that the temperature of the initiator in the pretreatment vessel is low based on the second temperature signal, the second controller 81 reduces the opening degree of the first valve body 30 or closes it to increase the flow rate of the heat exchange medium through the pretreatment heat exchanger 40 so that the initiator can quickly reach the target temperature. When the second controller 81 determines that the initiator in the pretreatment vessel has reached the target temperature based on the second temperature signal, the second controller 81 increases the opening degree of the first valve body 30 to allow a small portion of the heat exchange medium to pass through the pretreatment heat exchanger 40 so that the initiator is maintained at the target temperature.

[0037] The second temperature sensor 82 can capture minute temperature changes in real time (with an accuracy of ±0.1℃ to ±1℃), avoiding the lag and errors of manual monitoring. The second controller 81 calculates the deviation through a preset algorithm and can finely adjust the opening degree of the first valve body 30 to ensure that the actual temperature remains stable within the target range and reduce temperature fluctuations. At the same time, it eliminates the need for continuous manual monitoring and adjustment of the valve body, enabling real-time automatic temperature control, reducing errors caused by manual operation, and avoiding temperature exceedances or system failures due to untimely human adjustment.

[0038] like Figure 3 As shown, in one embodiment of this application, the second valve body 50 is a three-way switching valve. The three-way switching valve has a first valve port, a second valve port, and a third valve port. The first valve port is connected to the pretreatment heat exchanger 40, and the second valve port is connected to the reactor heat exchanger 10. The three-way switching valve is configured to switch the connection between the first valve port and the second valve port or the third valve port via the valve core, that is, the first valve port is connected to the second valve port or the first valve port is connected to the third valve port, while the second valve port and the third valve port are not connected.

[0039] The waste heat utilization system also includes: a steam generating device 100 and a liquid return pipeline.

[0040] The steam outlet of the steam generating device 100 is connected to the third valve port.

[0041] The return liquid pipeline connects the return steam port of the steam generating device 100 to the pretreatment heat exchanger 40.

[0042] When the ethoxylation reactor first starts working, there is no reaction in the reactor and no usable heat source. However, the initiator in the pretreatment vessel needs to be heated. At this time, the third valve port is connected to the first valve port, and the steam generating device 100 generates steam, which enters the pretreatment heat exchanger 40 to heat the initiator in the pretreatment vessel. After the ethoxylation reactor has been running for a period of time, the reaction in the reactor generates heat, which controls the three-way switching valve to connect the second valve port to the first valve port to utilize the residual heat generated during the production process of the ethoxylation reactor.

[0043] like Figure 3 and Figure 4 As shown, in one embodiment of this application, the waste heat utilization system further includes a third controller 91 and a third temperature sensor 92.

[0044] The third controller 91 is connected to the first valve body 30 and the second valve body 50. The third controller 91 is configured to control the switching between the valve ports of the second valve body 50 and the opening and closing degree of the first valve body 30.

[0045] The third temperature sensor 92 is connected to the third controller 91. The third temperature sensor 92 is configured to detect the temperature of the heat exchange medium at the outlet of the reactor heat exchanger 10 and send a third temperature signal to the third controller 91. When the third controller 91 determines, based on the third temperature signal, that the temperature of the heat exchange medium at the outlet of the reactor heat exchanger 10 has reached the required operating temperature, the third controller 91 controls the second valve body 50 to switch, connecting the second valve port to the first valve port (switching from connecting the third valve port to the first valve port to connecting the second valve port to the first valve port).

[0046] The third temperature sensor 92 can capture minute temperature changes in real time (with an accuracy of ±0.1℃ to ±1℃), avoiding the lag and errors of manual monitoring. The third controller 91 calculates the deviation through a preset algorithm, enabling precise control of the first valve body 30 and the second valve body 50. Simultaneously, it eliminates the need for continuous manual monitoring and adjustment of the valve bodies, achieving real-time automatic temperature control, reducing errors caused by manual operation, and preventing temperature exceedances or system malfunctions due to untimely human intervention.

[0047] Several embodiments of this application are described in detail below with reference to the accompanying drawings. Example 1 like Figure 5 As shown, the waste heat utilization system includes: a reactor heat exchanger 10, a circulating pump 20, a first valve body 30, a third pipeline, a pretreatment heat exchanger 40, and a second valve body 50.

[0048] The reactor heat exchanger 10 includes a small circulation heat exchanger 11 and a large circulation heat exchanger 12. The small circulation heat exchanger 11 is typically connected between the bottom outlet and the top inlet of the vertical reactor. In the initial stage of the reaction, when the liquid level in the vertical reactor reaches its minimum, the small circulation pump is activated. The material passes through the small circulation heat exchanger 11 via the pump, allowing the heat exchange medium within the small circulation heat exchanger 11 to cool the material. This enables the small amount of initiator and catalyst to quickly achieve uniform mixing and a suitable reaction temperature in the loop, preparing for the subsequent addition of ethylene oxide and contributing to improved initial reaction efficiency and stability. The large circulation heat exchanger 12 is connected between the large circulation outlet at the bottom of the vertical reactor and the large circulation inlet on the side of the horizontal reactor. When the liquid level in the vertical reactor reaches a certain value, ensuring the large circulation loop is full, the large circulation pump is started. The material passes through the large circulation heat exchanger 12 via the large circulation pump, allowing the heat exchange medium in the large circulation heat exchanger 12 to circulate and cool the material over a larger area. This allows for more complete contact and reaction between ethylene oxide and the material, improving the conversion rate and product quality. The small circulation heat exchanger 11 and the large circulation heat exchanger 12 work together in the ethoxylation unit to rationally control the material temperature and circulation path according to different stages and requirements of the reaction, thereby ensuring that the ethoxylation reaction proceeds efficiently and stably.

[0049] The outlet of the circulating pump 20 is connected to the inlet of the small circulating heat exchanger 11 and the large circulating heat exchanger 12 through the first pipe, and the return port of the circulating pump 20 is connected to the outlet of the small circulating heat exchanger 11 and the outlet of the large circulating heat exchanger 12 through two different second pipes.

[0050] The first valve body 30 is disposed on the second pipe connected to the small circulation heat exchanger 11, and the first valve body 30 is configured to control the flow rate of the heat exchange medium in the second pipe.

[0051] One port of the third pipe is connected to the second pipe located between the outlet of the small circulation heat exchanger 11 and the first valve body 30, and the other port of the third pipe is connected to the second pipe located between the return port and the first valve body 30.

[0052] The pretreatment heat exchanger 40 is located on the third pipe and is configured to heat the initiator in the pretreatment vessel. The second valve body 50 is disposed on the third pipeline and is configured to control the opening and closing of the third pipeline.

[0053] The small circulating heat exchanger 11 absorbs the heat released from the reaction in the reactor and rises in temperature. Through the cooperation between the second valve body 50 and the first valve body 30, at least part of the heat exchange medium flowing out of the small circulating heat exchanger 11 enters the pretreatment heat exchanger 40, so as to heat the initiator in the pretreatment reactor through the pretreatment heat exchanger 40. This fully utilizes the waste heat generated during the ethoxylation reaction process, improves the utilization efficiency of waste heat during the production process, and reduces the production energy cost.

[0054] The economic efficiency of the waste heat utilization system is illustrated below with reference to specific embodiments.

[0055] The heat required to raise 4000 kg of starting agent from an initial temperature of 60°C to a final temperature of 120°C is as follows: Q = Cp1×M×△T1=1.93×4000×(120-60)=4.632×10 6 KJ / h.

[0056] Cp1 is the isobaric specific heat capacity of the initiator, M1 is the weight of the initiator, and ΔT1 is the temperature increase required for the initiator.

[0057] Taking hot water as the heat exchange medium as an example, the flow rate of the hot water entering the pretreatment heat exchanger 40 is 117,000 KG / h, the inlet temperature of the hot water in the pretreatment heat exchanger 40 is 125℃, and the outlet temperature of the hot water in the pretreatment heat exchanger 40 is 100℃. The required heating time for the initiator is as follows: M2=Q / (Cp2×△T2)=4.632×10 6 / (4.2× (125-100))=44000KG; t= M2 / M1=44000 / 117000=0.38h; M2 is the weight of the hot water required for heating, Cp2 is the specific heat capacity of the hot water at constant pressure, ΔT2 is the temperature of the hot water reduced after passing through the pretreatment heat exchanger 40, t is the time required for the initiator to reach the final temperature, and M1 is the flow rate of the hot water entering the pretreatment heat exchanger 40.

[0058] The calculations are based on the intermittent production of three batches per day by the ethoxylation reactor: In existing technologies, steam is generally used to heat the hot water system. The unit price of steam is 250.2 yuan / ton. The daily steam required to heat the initiator to the termination temperature is 5 tons. The cost of steam to heat the initiator is: 250.2 × 5 = 1251 yuan.

[0059] The power of the circulating pump 20 in the waste heat utilization system is 20kw / h. The heating time for each batch of waste heat from the hot water is 0.38h. The electricity price is 0.7 yuan / kWh. The cost required for the waste heat utilization system to heat the initiator is 20×0.7×0.38×3=15.96 yuan.

[0060] The daily cost savings of using the waste heat recovery system compared to the existing equipment is: 1251 - 15.96 = 1235.04 yuan.

[0061] like Figure 6 As shown, in one embodiment, the waste heat recovery system further includes a fourth conduit and a third valve body 60.

[0062] The fourth pipe connects to the two second pipes. One port of the fourth pipe is connected to the large circulation heat exchanger 12, and the other port of the fourth pipe is located between the second valve body 50 and the small circulation heat exchanger 11.

[0063] The third valve body 60 is installed on the fourth pipe and is configured to control the flow rate of the heat exchange medium in the fourth pipe.

[0064] When the temperature of the heat exchange medium entering the pretreatment heat exchanger 40 is detected to be low, the third valve 60 is opened, and the opening degree of the third valve 60 is adjusted as needed, so that the heat exchange medium passing through the large circulation heat exchanger 12 also passes through the pretreatment heat exchanger 40. Since the temperature of the heat exchange medium flowing out of the large circulation heat exchanger 12 is higher, the temperature of the heat exchange medium entering the pretreatment heat exchanger 40 is increased, so that the temperature of the initiator quickly reaches the target temperature, thereby improving production efficiency. In one embodiment of this application, a valve body can also be installed on the second pipe connecting the outlet of the large circulation heat exchanger 12 and the return port of the circulation pump 20, which can cut off the connection between the outlet of the large circulation heat exchanger 12 and the return port of the circulation pump 20, so that all the heat exchange medium passing through the large circulation heat exchanger 12 passes through the pretreatment heat exchanger 40.

[0065] like Figure 6 and Figure 7 As shown, in one embodiment, the waste heat utilization system further includes a first controller 71 and a first temperature sensor 72.

[0066] The first controller 71 is connected to the third valve body 60, and the first controller 71 is configured to control the opening and closing degree of the third valve body 60.

[0067] The first temperature sensor 72 is connected to the first controller 71. The first temperature sensor 72 is configured to detect the temperature of the heat exchange medium entering the pretreatment heat exchanger 40 and send a first temperature signal to the first controller 71.

[0068] The first temperature sensor 72 can capture minute temperature changes in real time (with an accuracy of ±0.1℃ to ±1℃), avoiding the lag and errors of manual monitoring. The first controller 71 calculates the deviation through a preset algorithm, enabling precise control of the third valve body 60. Simultaneously, it eliminates the need for continuous manual monitoring and adjustment of the valve body, achieving real-time automatic temperature control, reducing errors caused by manual operation, and preventing temperature exceedances or system malfunctions due to untimely human intervention.

[0069] Example 2 like Figure 8 As shown, the scheme of Embodiment 2 is largely the same as that of Embodiment 1, with the main difference being that the first valve body 30 is installed on the second pipe that is connected to the large circulation heat exchanger 12.

[0070] The third pipe is connected to the outlet of the large circulation heat exchanger 12.

[0071] The large circulation heat exchanger 12 absorbs the heat released by the reaction in the reactor and rises in temperature. Through the cooperation between the second valve body 50 and the first valve body 30, at least part of the heat exchange medium flowing out of the reactor heat exchanger 10 enters the pretreatment heat exchanger 40, so as to heat the initiator in the pretreatment reactor through the pretreatment heat exchanger 40. This fully utilizes the waste heat generated during the production process of the ethoxylation reactor, improves the utilization efficiency of waste heat during the production process, and reduces the production energy cost.

[0072] Example 3 like Figure 9 As shown, the scheme of Embodiment 3 is largely the same as that of Embodiment 1, with the main difference being that the second pipeline includes a first branch pipeline, a second branch pipeline, and a junction pipeline.

[0073] One end of the first branch pipe is connected to the small circulation heat exchanger 11, and one end of the second branch pipe is connected to the large circulation heat exchanger 12.

[0074] One end of the manifold is connected to the circulating pump 20, and the other end of the manifold is connected to the other end of the first branch pipe and the other end of the second branch pipe.

[0075] The first valve body 30 is installed on the manifold.

[0076] The third pipeline is connected in parallel with the manifold.

[0077] The small circulating heat exchanger 11 and the large circulating heat exchanger 12 absorb the heat released from the reaction in the reactor and rise in temperature. Through the cooperation between the second valve body 50 and the first valve body 30, at least part of the heat exchange medium flowing out of the reactor heat exchanger 10 enters the pretreatment heat exchanger 40, so as to heat the initiator in the pretreatment reactor through the pretreatment heat exchanger 40. This fully utilizes the waste heat generated during the production process of the ethoxylation reactor, improves the utilization efficiency of waste heat during the production process, and thus reduces the production energy cost.

[0078] In one embodiment of this application, the first controller 71, the second controller 81, and the third controller 91 may be the same controller or different controllers.

[0079] The ethoxylation reaction apparatus provided in the second aspect of this application includes: a pretreatment vessel, a reaction vessel, and the above-mentioned waste heat utilization system.

[0080] The pretreatment vessel is configured to pretreat the initiator.

[0081] The reactor is connected to the pretreatment vessel.

[0082] The waste heat utilization system's reactor heat exchanger is installed on the reactor, and the waste heat utilization system's pretreatment heat exchanger is installed on the pretreatment vessel.

[0083] The ethoxylation reaction apparatus provided in this application embodiment has the same technical effect as the waste heat utilization system provided in the above embodiment, and will not be described again here.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A waste heat recovery system for an ethoxylation reaction apparatus, characterized in that, include: A reactor heat exchanger, the reactor heat exchanger being configured to absorb heat from the reactor; A circulating pump, the outlet of which is connected to the inlet of the reactor heat exchanger via a first pipe, and the return port of which is connected to the outlet of the reactor heat exchanger via a second pipe; A first valve body is disposed on the second pipeline and is configured to control the flow rate of the heat exchange medium in the second pipeline. A third pipe, one port of which is connected to a second pipe located between the outlet and the first valve body, and the other port of which is connected to a second pipe located between the return port and the first valve body; A pretreatment heat exchanger, disposed on the third conduit, is configured to heat the initiator within the pretreatment vessel; and A second valve body is disposed on the third pipe and is configured to control the on / off state of the third pipe.

2. The waste heat utilization system according to claim 1, characterized in that, The reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger. The small circulation heat exchanger and the large circulation heat exchanger are respectively connected to the circulation pump through two different second pipes; The first valve body is installed on the second pipe that is connected to the small circulation heat exchanger; The third pipe is connected to the outlet of the small circulation heat exchanger.

3. The waste heat utilization system according to claim 2, characterized in that, Also includes: A fourth pipe, which connects two of the second pipes, has one port connected to the large circulation heat exchanger and the other port located between the second valve body and the small circulation heat exchanger; as well as A third valve body is disposed on the fourth pipe and is configured to control the flow rate of the heat exchange medium in the fourth pipe.

4. The waste heat utilization system according to claim 3, characterized in that, Also includes: A first controller is connected to the third valve body and is configured to control the opening degree of the third valve body. as well as A first temperature sensor is connected to the first controller. The first temperature sensor is configured to detect the temperature of the heat exchange medium entering the pretreatment heat exchanger and send a first temperature signal to the first controller.

5. The waste heat utilization system according to claim 1, characterized in that, The reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger. The small circulation heat exchanger and the large circulation heat exchanger are respectively connected to the circulation pump through two different second pipes; The first valve body is installed on the second pipe that is connected to the large circulation heat exchanger; The third pipe is connected to the outlet of the large circulation heat exchanger.

6. The waste heat utilization system according to claim 1, characterized in that, The reactor heat exchanger includes a small circulation heat exchanger and a large circulation heat exchanger. The second pipeline includes a first branch pipeline, a second branch pipeline, and a junction pipeline; One end of the first branch pipe is connected to the small circulation heat exchanger, and one end of the second branch pipe is connected to the large circulation heat exchanger; One end of the manifold is connected to the circulation pump, and the other end of the manifold is connected to the other end of the first branch pipe and the other end of the second branch pipe, respectively. The first valve body is mounted on the manifold. The third pipe is connected in parallel with the manifold.

7. The waste heat utilization system according to any one of claims 1 to 6, characterized in that, It also includes: a second controller connected to the first valve body, the second controller being configured to control the opening and closing degree of the first valve body; and A second temperature sensor is connected to the second controller. The second temperature sensor is configured to detect the temperature of the initiator in the pretreatment vessel and send a second temperature signal to the second controller.

8. The waste heat recovery system according to any one of claims 1 to 6, characterized in that, The second valve body is a three-way switching valve, which has a first valve port, a second valve port and a third valve port. The first valve port is connected to the pretreatment heat exchanger, and the second valve port is connected to the reactor heat exchanger. The three-way switching valve is configured to switch the first valve port to the second valve port or the third valve port through the valve core. The waste heat recovery system further includes: a steam generating device, the steam outlet of which is connected to the third valve port; and A return liquid pipeline connects the return steam port of the steam generating device to the pretreatment heat exchanger.

9. The waste heat utilization system according to claim 8, characterized in that, Also includes: A third controller is connected to the first valve body and the second valve body, and the third controller is configured to control the switching between the valve ports of the second valve body and the opening degree of the first valve body. as well as The third temperature sensor is connected to the third controller and is configured to detect the temperature of the heat exchange medium at the outlet of the reactor heat exchanger and send a third temperature signal to the third controller.

10. An ethoxylation reaction apparatus, characterized in that, include: A pretreatment vessel configured to pretreat the initiator; A reaction vessel, which is connected to the pretreatment vessel; as well as The waste heat utilization system according to any one of claims 1 to 9, wherein the reactor heat exchanger of the waste heat utilization system is disposed on the reactor, and the pretreatment heat exchanger of the waste heat utilization system is disposed on the pretreatment reactor.

Images