A stripping tower overhead heat and desalted water heating recovery device

Abstract

The utility model relates to recovery device technical field discloses a kind of stripping column overhead waste heat and desalted water heating recovery device, including base, the base upper end one side is fixedly arranged with stripping column body, the stripping column body top is fixedly arranged with connecting pipe, the base middle part is fixedly arranged with cooler in front end, the cooler upper end is fixedly arranged with first desalted water heater, the first desalted water heater rear end is fixedly arranged with second desalted water heater, the base upper end middle part is fixedly arranged with oxygen-remover in rear end, the base upper end is fixedly arranged with separator in side away from stripping column body.Originally, in the utility model, the high-temperature waste heat at the top of the column, which was directly cooled and discarded, is used to preheat the desalted water of the boiler, reducing the consumption of low-pressure steam required by the oxygen-remover, and reducing the overall energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of recovery device technology, and in particular to a device for recovering waste heat and demineralized water from the top of a stripping tower. Background Technology

[0002] Stripping is a unit operation used to recover absorbed solutes and separate the absorbent from the solutes to achieve regeneration. In some cases, stripping is also used to remove light components from liquids. For example, in the oil refining industry, steam is often used as a stripping agent to remove light components from oil products. Therefore, stripping can be used in combination with absorption or alone. In the coal-to-ammonia and methanol-to-sulfur conversion process, in order to reduce the ammonia content in the process condensate, the process condensate needs to be sent to a stripping tower for stripping to remove ammonia.

[0003] Existing stripping tower top waste heat and demineralized water heating and recovery devices mostly use a single heat exchanger to simply cool the high-temperature air at the top of the tower. This results in a large amount of medium and low-temperature waste heat being directly discharged through the water cooler without effective recovery and utilization. Moreover, the heat exchange tubes are mostly straight tubes or ordinary coils, with limited heat exchange area and low heat transfer efficiency. This can easily lead to uneven heat exchange in certain areas or even thermal stress concentration. Therefore, those skilled in the art have provided a stripping tower top waste heat and demineralized water heating and recovery device to solve the problems mentioned in the background art. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a stripping tower top waste heat and demineralized water heating and recovery device. By utilizing the high-temperature waste heat from the top of the tower, which was originally directly cooled and discarded, it is used to preheat the boiler demineralized water, reducing the consumption of low-pressure steam required by the deaerator, lowering the overall energy consumption. Furthermore, the spiral connecting pipe increases the heat exchange area, enhances the heat transfer process, avoids local overheating or heat exchange dead zones, and ensures uniform and rapid heat transfer.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A device for recovering waste heat from the top of a stripping tower and heating and recovering demineralized water includes a base. A stripping tower body is fixedly installed on one side of the upper end of the base. A connecting pipe is fixedly installed on the top of the stripping tower body. A cooler is fixedly installed in the middle of the base near the front end. A first demineralized water heater is fixedly installed on the upper end of the cooler. A second demineralized water heater is fixedly installed at the rear end of the first demineralized water heater. A deaerator is fixedly installed in the middle of the upper end of the base near the rear end. A separator is fixedly installed on the upper end of the base away from the stripping tower body.

[0007] Furthermore, the connecting pipe is disposed outside the first demineralized water heater, and the outside of the connecting pipe is spiral-shaped.

[0008] Furthermore, the output end of the connecting pipe is fixedly installed at the upper end of the cooler, and is used to guide the gas after releasing waste heat into the cooler.

[0009] Furthermore, the front end of the second demineralized water heater is fixedly disposed at the rear end of the first demineralized water heater, and the lower end of the second demineralized water heater is fixedly disposed at the upper end of the deaerator.

[0010] Furthermore, the rear end of the first demineralized water heater is fixedly installed at the front end of the deaerator to reduce the consumption of low-pressure steam by the deaerator.

[0011] Furthermore, one side of the cooler is fixedly installed on the side of the separator near the stripping tower body, and is used to send the cooled gas-liquid mixture into the separator for gas-liquid separation.

[0012] Furthermore, a temperature sensor is fixedly installed at the output end of the first demineralized water heater to monitor whether the temperature of the demineralized water reaches a preset threshold.

[0013] This utility model has the following beneficial effects:

[0014] This invention proposes a waste heat recovery device for the top of a stripping tower and for heating and recovering demineralized water. During the operation of the stripping tower, the high-temperature air generated at its top is transported through a connecting pipe. As the high-temperature air flows slowly within the spiral tube, its residual heat is transferred to the demineralized water in the first demineralized water heater chamber, causing the high-temperature air to gradually release heat and lower its temperature. The spiral connecting pipe increases the contact area with the demineralized water, effectively avoiding local heat exchange dead zones and uneven temperature, thus improving the efficiency and stability of heat exchange. Subsequently, after being cooled by a cooler, the demineralized water enters the separator for separation. When the temperature of the demineralized water reaches a preset threshold, it is directly transported to the deaerator through a dedicated pipeline. The preheating of the demineralized water does not require additional steam energy consumption, directly reducing the steam consumption of the deaerator and thus reducing the overall cost. Attached Figure Description

[0015] Figure 1 This is a frontal axonometric view of the entire utility model;

[0016] Figure 2 This is a rear-view axonometric schematic diagram of the entire utility model;

[0017] Figure 3 This is an isometric view of the present invention near the connecting pipe;

[0018] Figure 4 This is a schematic diagram of the overall process of this utility model.

[0019] Legend:

[0020] 1. Stripping tower body; 2. Connecting pipe; 3. First demineralized water heater; 4. Second demineralized water heater; 5. Cooler; 6. Separator; 7. Deaerator; 8. Base. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Reference Figures 1-4 One embodiment provided by this utility model:

[0023] A stripping tower top waste heat and demineralized water heating and recovery device includes a base 8, a stripping tower body 1 fixedly installed on one side of the upper end of the base 8, a connecting pipe 2 fixedly installed on the top of the stripping tower body 1, a cooler 5 fixedly installed in the middle of the base 8 near the front end, a first demineralized water heater 3 fixedly installed on the upper end of the cooler 5, a second demineralized water heater 4 fixedly installed at the rear end of the first demineralized water heater 3, a deaerator 7 fixedly installed in the middle of the upper end of the base 8 near the rear end, and a separator 6 fixedly installed on the upper end of the base 8 away from the stripping tower body 1.

[0024] The connecting pipe 2 is externally located inside the first demineralized water heater 3. The connecting pipe 2 is spirally shaped. The output end of the connecting pipe 2 is fixedly located at the upper end of the cooler 5 to introduce the gas after releasing residual heat into the cooler 5. The front end of the second demineralized water heater 4 is fixedly located at the rear end of the first demineralized water heater 3. The lower end of the second demineralized water heater 4 is fixedly located at the upper end of the deaerator 7. The rear end of the first demineralized water heater 3 is fixedly located at the front end of the deaerator 7 to reduce the consumption of low-pressure steam by the deaerator 7. One side of the cooler 5 is fixedly located on the side of the separator 6 near the stripping tower body 1 to send the cooled gas-liquid mixture into the separator 6 for gas-liquid separation. A temperature sensor is fixedly installed at the output end of the first demineralized water heater 3 to monitor whether the demineralized water temperature reaches the preset threshold.

[0025] Specifically, during the operation of the stripping tower body 1, the high-temperature air discharged from the top of the tower will be led out through the connecting pipe 2, which is fixedly connected to the top of the stripping tower body 1. The connecting pipe 2 has a spiral structure on the outside and is nested inside the first demineralized water heater 3. When the high-temperature gas flows in the spiral pipe, the waste heat it carries is efficiently transferred to the demineralized water in the first demineralized water heater 3 through the pipe wall, realizing heat recovery. During this process, the high-temperature gas will gradually release heat, causing the temperature of the high-temperature gas to drop continuously. At the same time, the spiral structure increases the heat exchange area, effectively avoiding the problem of uneven local heat exchange and improving the overall heat exchange efficiency.

[0026] Before use, the ambient temperature demineralized water is introduced into the first demineralized water heater 3 through the second demineralized water heater 4. In the first demineralized water heater 3, the demineralized water inside will fully absorb the heat from the spiral connecting pipe 2, causing its temperature to gradually rise. When the water temperature reaches the process set value, the preheated demineralized water is directly sent to the deaerator 7 through the pipeline to complete the preheating process of the boiler feedwater, thereby significantly reducing the amount of low-pressure steam required by the deaerator 7 and reducing the overall energy consumption.

[0027] After releasing residual heat, the gas will enter the cooler 5 located in the middle of the base 8 from the output end of the connecting pipe 2 for further cooling. After being processed by the cooler 5, the gas temperature will drop to a range that meets the requirements of subsequent tail gas treatment. The resulting gas-liquid mixture will then be transported to the separator 6. In the separator 6, the gas and condensate will be effectively separated. The non-condensable gas will be sent to the tail gas treatment unit according to the process requirements, and the condensate will be recycled into the corresponding recovery device. This will effectively reduce the heat load of the cooler 5, reduce the consumption of circulating cooling water, and extend the service life of the cooler 5.

[0028] It should be noted that the stripping tower body 1, the first demineralized water heater 3, the second demineralized water heater 4, the cooler 5, the separator 6, the deaerator 7, and the temperature sensor are all existing devices or equipment, or devices or equipment that can be implemented with existing technology. Their functions, specific components, and principles are clear to those skilled in the art, so they will not be described in detail here.

[0029] The connecting pipe 2 is a corrosion-resistant metal spiral coil, which is placed inside the shell of the first demineralized water heater 3 as a heat exchange tube bundle. The demineralized water flows in the shell side and the high-temperature gas flows in the tube side, realizing efficient indirect heat exchange. The second demineralized water heater 4 is used to preheat the demineralized water at room temperature before introducing it into the first demineralized water heater 3 for deep heating, further improving the heat exchange efficiency and ensuring that the demineralized water quickly reaches the preset temperature. The demineralized water first enters the second demineralized water heater 4 for initial heating, and then is transported to the first demineralized water heater 3 through the guide pipe. The two heaters are set in series to form a two-stage heating process, improving the waste heat utilization rate.

[0030] When the temperature sensor detects that the temperature of the demineralized water has not reached the preset threshold, the residence time of the demineralized water in the first demineralized water heater 3 will be extended to ensure that it meets the standard before being sent to the deaerator 7. The condensate separated by the separator 6 can be used as process makeup water and reintroduced into the stripping tower or other production units to realize the recycling of water resources. A safety valve is installed at the inlet of the connecting pipe 2. When the pressure at the top of the tower rises abnormally, the safety valve will open automatically to discharge excess gas into the flare system to avoid damage to the connecting pipe 2 or the heater due to overpressure.

[0031] Corrosion-resistant sealing gaskets made of fluororubber are installed at the connection points between the connecting pipe 2 and the first demineralized water heater 3 and the cooler 5. At the same time, the inner wall of the connecting pipe 2 is treated with an anti-corrosion coating to prevent high-temperature gas from corroding the pipe and to ensure sealing performance and service life. A pressure sensor and a pressure relief valve are installed at the input end of the connecting pipe 2. When the gas pressure at the top of the tower exceeds the preset value, the pressure relief valve opens automatically to divert the excess gas to the tail gas treatment unit to avoid overload of the pipe and heater. This is a mature and publicly available technology in the prior art. Therefore, its specific structure and working principle will not be described in detail in this article.

[0032] Both the first demineralized water heater 3 and the second demineralized water heater 4 are equipped with spiral guide plates to guide the demineralized water to flow evenly. At the same time, the inner wall of the heater is coated with an anti-scaling coating to reduce scale adhesion and reduce maintenance frequency. The circuit connection adopts the conventional connection method in the prior art, so it will not be described in detail. All contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0033] Working principle: During operation, the stripping tower body 1 generates high-temperature air inside. The generated high-temperature air is output through the connecting pipe 2 fixed at the top of the stripping tower body 1. When the high-temperature gas flows inside the spiral connecting pipe 2, the waste heat it carries is quickly transferred through the pipe wall to the demineralized water inside the first demineralized water heater 3. During this process, the high-temperature air releases heat, causing its temperature to gradually decrease. At the same time, the spiral structure greatly increases the contact area between the connecting pipe 2 and the demineralized water, avoiding uneven local heat exchange and improving heat exchange efficiency.

[0034] Before use, ambient temperature demineralized water from the outside will enter the interior of the first demineralized water heater 3 through the second demineralized water heater 4. The ambient temperature demineralized water will absorb the heat transferred by the connecting pipe 2, thereby gradually increasing the temperature of the demineralized water inside the first demineralized water heater 3. When the demineralized water inside the first demineralized water heater 3 reaches the set temperature, it will be directly sent to the deaerator 7 through the pipeline to complete the preheating process of the demineralized water.

[0035] After releasing waste heat, the high-temperature gas will enter the cooler 5 through the connecting pipe 2. The cooler 5 will continue to cool the high-temperature gas. When the high-temperature gas is cooled to the temperature required for the process tail gas treatment, the cooled gas-liquid mixture will be sent into the separator 6 through the pipeline. The separated gas will be processed according to the subsequent process requirements, and the liquid will enter the corresponding recovery device. The whole process not only completes the waste heat recovery, but also does not interrupt the original tower top hot steam cooling and separation process, ensuring process continuity.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A device for recovering waste heat and demineralized water from the top of a stripping tower, comprising a base (8), characterized in that: A stripping tower body (1) is fixedly installed on one side of the upper end of the base (8). A connecting pipe (2) is fixedly installed on the top of the stripping tower body (1). A cooler (5) is fixedly installed in the middle of the base (8) near the front end. A first demineralized water heater (3) is fixedly installed on the upper end of the cooler (5). A second demineralized water heater (4) is fixedly installed at the rear end of the first demineralized water heater (3). A deaerator (7) is fixedly installed in the middle of the upper end of the base (8) near the rear end. A separator (6) is fixedly installed on the side of the upper end of the base (8) away from the stripping tower body (1).

2. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: The connecting pipe (2) is located outside the first demineralized water heater (3), and the outside of the connecting pipe (2) is spiral-shaped.

3. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: The output end of the connecting pipe (2) is fixedly installed at the upper end of the cooler (5) to introduce the gas after releasing residual heat into the cooler (5).

4. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: The front end of the second demineralized water heater (4) is fixedly installed at the rear end of the first demineralized water heater (3), and the lower end of the second demineralized water heater (4) is fixedly installed at the upper end of the deaerator (7).

5. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: The rear end of the first demineralized water heater (3) is fixedly installed at the front end of the deaerator (7) to reduce the consumption of low-pressure steam by the deaerator (7).

6. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: The cooler (5) is fixedly installed on one side of the separator (6) near the stripper tower body (1) to send the cooled gas-liquid mixture into the separator (6) for gas-liquid separation.

7. The stripping tower top waste heat and demineralized water heating and recovery device according to claim 1, characterized in that: A temperature sensor is fixedly installed at the output end of the first demineralized water heater (3) to monitor whether the temperature of the demineralized water reaches a preset threshold.

Images