A system and method for recycling wash oil entrained in coal gas

Abstract

The present invention discloses a system and method for recycling the wash oil entrained in coal gas. The system includes: an underground tank for collecting the residual wash oil entrained in the coal gas from the debenzolization column; a regenerator residue tank connected to the outlet of the underground tank for heating the residual wash oil from the underground tank; and a wash oil regenerator connected to the outlet of the regenerator residue tank for regenerating the heated residual wash oil. The method includes: conveying the collected residual wash oil entrained in the coal gas to the regenerator residue tank for heating to achieve water-oil separation, reducing the water content in the residual wash oil to obtain hot wash oil; and conveying the hot wash oil to the wash oil regenerator for regeneration and then recycling. The system for recycling the wash oil entrained in coal gas disclosed by the present invention has small modifications and low costs on the basis of the existing system; uses the residue tank heating system to ensure the stable operation of the regenerator; and at the same time reduces the light oil entering the circulating ammonia water and reduces the load of ammonia distillation and biochemical operation.

Description

Technical Field

[0001] The present invention belongs to the chemical industry field, and relates to a technology for capturing wash oil entrained in coal gas by a mist eliminator and recycling it by a wash oil regeneration and distillation device. Background Art

[0002] Currently, in the crude benzene recovery process of coking plants, wash oil is sprayed on coke oven gas. According to the principle of similarity compatibility, after absorbing benzene in the coke oven gas, the benzene-containing wash oil is formed and enters the debenzolization column for fractionation. Utilizing the different boiling points of crude benzene and wash oil, the crude benzene and wash oil are separated. The crude benzene enters the product tank and is sold as a product to generate benefits; the wash oil continues to enter the debenzolization column to absorb benzene in the gas and is recycled. After the coke oven gas is washed by the wash oil, the benzene content in the gas is reduced from 25 g / m 3 to 5 g / m 3 or less and can be directly supplied to users.

[0003] However, during the process of the wash oil absorbing crude benzene, the wash oil is in convective contact with the coke oven gas. Part of the wash oil is dissolved in the coke oven gas. At the same time, due to the too fast flow rate of the coke oven gas, part of the wash oil is entrained by the coke oven gas. The wash oil entrained in the gas passes through the mist eliminator, and the wash oil is captured together with the moisture and enters the underground tank for collection. The collected wash oil is transported to the mechanical clarifier by an underground pump. Since the residual wash oil contains a large amount of light oil, the oil content in the circulating ammonia water increases. The oil content in the circulating ammonia water can reach 500 mg / m 3 and the COD can reach 12000 mg / m 3 , resulting in a high operating load of the ammonia distillation and biochemical systems. If the wash oil collected in the underground tank is not recovered and disposed of as residual wash oil, it will lead to an increase in the consumption of wash oil.

[0004] In addition, since the residual wash oil collected in the underground tank has a relatively high water content, reaching more than 50%, when directly used as supplementary wash oil together with the new wash oil, it will reduce the quality of the wash oil, affect the absorption effect of crude benzene, and at the same time, there are more impurities, which is likely to cause unstable operation of the circulation system.

[0005] If the residual wash oil is directly transported to the wash oil regenerator for regeneration and utilization, due to the high water content and large temperature difference, when the temperature reaches 190°C of the wash oil, the regenerator vibrates and the wash oil cannot be normally regenerated. Summary of the Invention

[0006] In view of the problem that the entrained wash oil in the existing gas enters the mechanical clarifier without being recycled, resulting in too high oil content in the ammonia water circulation system, high operating load of the ammonia distillation and biochemical systems, and the problem that if the residual wash oil directly enters the wash oil regenerator for regeneration, the wash oil regenerator fluctuates due to the presence of moisture and large temperature difference, the present invention provides a convenient and easy-to-operate system for recycling the entrained wash oil in the gas, effectively recovering the entrained wash oil in the gas, reducing the oil content of the circulating ammonia water, improving the operation stability of ammonia distillation and biochemical processes, and reducing the wash oil consumption.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A system for recycling the entrained wash oil in the gas, the system comprising:

[0009] An underground tank for collecting the residual wash oil entrained in the gas from the debenzolization column;

[0010] A regenerator residue tank connected to the outlet of the underground tank for heating the residual wash oil from the underground tank; and

[0011] A wash oil regenerator connected to the outlet of the regenerator residue tank for regenerating the heated residual wash oil.

[0012] In the above system, as a preferred embodiment, the system further comprises: a mist eliminator disposed at the gas outlet of the debenzolization column for collecting the residual wash oil entrained in the gas.

[0013] In the above system, as a preferred embodiment, the system further comprises a mist eliminator water seal disposed at the liquid outlet of the mist eliminator, and the residual wash oil entrained in the gas from the debenzolization column is transported to the underground tank through the mist eliminator water seal.

[0014] In the above system, as a preferred embodiment, an underground tank transfer pump is disposed between the underground tank and the regenerator residue tank for pumping the residual wash oil from the underground tank into the regenerator residue tank.

[0015] In the above system, as a preferred embodiment, a first valve is disposed on the first pipeline connecting the underground tank transfer pump and the regenerator residue tank for controlling the entry of the residual wash oil into the regenerator residue tank.

[0016] In the above system, as a preferred embodiment, the system further comprises a mechanical clarifier, the mechanical clarifier is connected to the underground tank, and a second valve is disposed on the second pipeline connecting the underground tank transfer pump and the mechanical clarifier for controlling the entry of the residual wash oil into the mechanical clarifier.

[0017] In the present invention, under the condition that the system operates normally, the first valve is in an open state, so that the residual wash oil collected from the underground tank enters the regenerator residue tank; when the wash oil regenerator fails and needs to be repaired, the first valve is closed and the second valve is opened. At this time, the residual wash oil collected from the underground tank directly enters the mechanical clarifying tank.

[0018] In the above system, as a preferred embodiment, a heating element is provided on the regenerator residue tank for heating and separating the residual wash oil conveyed to the regenerator residue tank.

[0019] In the above system, as a preferred embodiment, the heating element provides heat through a steam system. Preferably, the steam in the steam system is sourced from the steam generated in the chemical production area.

[0020] In the present invention, in the regenerator residue tank, by heating the residual wash oil from the underground tank, the temperature difference between the residual wash oil directly entering the wash oil regenerator is reduced.

[0021] In the above system, as a preferred embodiment, the mechanical clarifying tank is also connected to the outlet of the regenerator residue tank for collecting the residual moisture separated by heating in the regenerator residue tank.

[0022] The present invention also provides a method for recycling the wash oil entrained in the coal gas. The specific technical solution is as follows:

[0023] A method for recycling the wash oil entrained in the coal gas is realized by using the above system for recycling the wash oil entrained in the coal gas. The method includes:

[0024] Conveying the residual wash oil entrained in the collected coal gas to the regenerator residue tank for heating to achieve water-oil separation, reducing the moisture content in the residual wash oil, and obtaining hot wash oil; conveying the hot wash oil to the wash oil regenerator for regeneration and then recycling.

[0025] In the above method, as a preferred embodiment, the heating temperature is 75-90 °C, preferably 80 °C.

[0026] In the above method, as a preferred embodiment, the oil content in the hot wash oil is ≥90%, and the water content is 5%-10%.

[0027] In the above method, as a preferred embodiment, the regeneration temperature of the wash oil regenerator is 150-200 °C.

[0028] In the above method, as a preferred embodiment, heating the collected residual wash oil also yields residual moisture, and the residual moisture is conveyed to the mechanical clarifying tank for separation and then enters the ammonia distillation system.

[0029] In the present invention, the residual moisture includes two parts of water. One is the water contained in the residual wash oil, and the other is the water cooled from the steam transported through the steam heating valve.

[0030] In the above method, as a preferred embodiment, in the ammonia distillation system, the oil content of the circulating ammonia water is <200 mg / L, and the COD is <8000 mg / L.

[0031] In the above method, as a preferred embodiment, the water content of the residual wash oil can reach 50%.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) The wash oil entrained in the gas is collected by the mist eliminator. Through the mist eliminator water seal and the underground tank collection system, it is directly transported to the regenerator residue tank for heating by the underground tank pump. Based on the existing system for recycling the entrained wash oil in the gas, the modification is small and the cost is low.

[0034] (2) On the existing system, directly using the heating system of the regenerator residue tank, the recycled residual wash oil is heated to 80 °C, reducing the temperature difference directly entering the wash oil regenerator. At the same time, most of the water in the residual wash oil is removed, and the wash oil regenerator still operates stably when the temperature reaches 190 °C.

[0035] (3) On the existing system, after direct heating and separation using the residue tank, the heated wash oil enters the wash oil regenerator for recycling. The wash oil content in the remaining water is reduced. After separation by the original system and then ammonia distillation in the mechanized clarifying tank, the light oil entering the circulating ammonia water is reduced, and the loads of ammonia distillation and biochemical operation are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. Among them:

[0037] Figure 1 It is a schematic structural diagram of the system for recycling residual wash oil in the gas in the specific embodiment of the present invention.

[0038] Description of the reference numerals in the drawings: 1, mist eliminator; 2, mist eliminator water seal; 3, underground tank; 4, underground tank transfer pump; 5, second valve; 6, first valve; 7, first pipeline; 8, regenerator residue tank; 9, steam heating valve; 10, second pipeline; 11, mechanized clarifying tank; 12, third pipeline; 13, third valve; 14, regenerator residue tank transfer pump; 15, fourth valve; 16, fifth valve; 17, fourth pipeline; 18, sixth valve; 19, wash oil regenerator. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention rather than limitation thereof. In fact, those skilled in the art will appreciate that modifications and variations can be made to the present invention without departing from the scope or spirit thereof. For example, features shown or described as part of one embodiment can be used in another embodiment to yield yet another embodiment. Accordingly, it is intended that the present invention embrace such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0040] The terms "connected", "coupled", and "arranged" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate component; it can be a wired connection, a radio connection, or a wireless communication signal connection. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0041] See Figure 1 , a specific embodiment of the present invention provides a system for recycling entrained wash oil in gas, which system includes an underground tank 3 for collecting the residual wash oil entrained in the gas from the debenzolization column, a regenerator residue tank 8 connected to the outlet of the underground tank 3 for heating the residual wash oil from the underground tank 3, and a wash oil regenerator 19 for regenerating the heated residual wash oil and connected to the outlet of the regenerator residue tank 8. The system may further include: a mist eliminator 1 for trapping the residual wash oil entrained in the gas, a mist eliminator water seal 2 for transporting the residual wash oil, and a mechanical clarifier tank 11 connected to the underground tank. Each component and device included in the system of the present invention will be described one by one below.

[0042] The mist eliminator 1 is arranged at the gas outlet of the debenzolization column for trapping the residual wash oil entrained in the gas.

[0043] The mist eliminator water seal 2 is arranged at the liquid outlet of the mist eliminator 1, and the residual wash oil entrained in the gas from the debenzolization column is transported to the underground tank 3 through the mist eliminator water seal 2.

[0044] The underground tank 3 is connected to the outlet of the mist eliminator 1 for collecting the residual wash oil entrained in the gas from the debenzolization column.

[0045] The residual wash oil entrained in the gas from the debenzolization column is obtained by the mist eliminator 1 arranged above the debenzolization column; further, the residual wash oil entrained in the gas from the debenzolization column is transported to the underground tank 3 through the mist eliminator water seal 2 arranged at the liquid outlet of the mist eliminator 1.

[0046] The regenerator residue tank 8 is connected to the outlet of the underground tank 3 for heating the residual wash oil from the underground tank 3 and separating oil and water therefrom.

[0047] Furthermore, an underground tank transfer pump 4 is provided between the underground tank 3 and the regenerator residue tank 8 for pumping the residual wash oil from the underground tank 3 into the regenerator residue tank 8.

[0048] Furthermore, a first valve 6 is provided on the first pipeline 7 connecting the underground tank transfer pump 4 and the regenerator residue tank 8 for controlling the entry of the residual wash oil from the underground tank 3 into the regenerator residue tank 8;

[0049] Furthermore, a heating element is provided on the regenerator residue tank 8 for heating and separating the residual wash oil transported to the regenerator residue tank 8 to obtain hot wash oil and residual moisture; the heating element can adopt a conventional heating element in the art, and the heating element provides heat through a steam system, such as providing heat through a steam heating valve 9; the heating element provided on the regenerator residue tank 8 is used to heat the residual wash oil transported to the regenerator residue tank 8, such as heating to 80 °C, to reduce the temperature difference between the residual wash oil directly entering the wash oil regenerator, and at the same time remove most of the moisture in the residual wash oil to ensure the stable operation of the wash oil regenerator 19. Among them, the residual moisture mainly includes two parts of water, one is the water contained in the residual wash oil, and the other is the water cooled from the steam transported through the steam heating valve. The steam in the steam system comes from the steam generated in the chemical production area.

[0050] In the present invention, in the regenerator residue tank, by heating the residual wash oil from the underground tank 3, it is used to reduce the temperature difference between the residual wash oil directly entering the wash oil regenerator.

[0051] The wash oil regenerator 19 is connected to the outlet of the regenerator residue tank 8 for regenerating the heated residual wash oil.

[0052] Furthermore, a regenerator residue tank transfer pump 14 is provided between the wash oil regenerator 19 and the regenerator residue tank 8 for transporting the hot wash oil after heating and separation to the wash oil regenerator 19. A fifth valve 16 and a sixth valve 18 are provided on the fourth pipeline 17 connecting the wash oil regenerator 19 and the regenerator residue tank 8 for controlling the entry of the hot wash oil from the regenerator residue tank 8 into the wash oil regenerator 19.

[0053] In the present invention, since the pipeline from the outlet of the regenerator residue tank transfer pump 14 to the wash oil regenerator 19 is relatively long, when transporting the residual moisture, the hot wash oil is likely to stay in the pipeline, or the steam generated during the regeneration of the wash oil in the wash oil regenerator 19 is likely to condense in the pipeline. In order to prevent the hot wash oil from staying in the pipeline or prevent the steam from condensing in the pipeline during the regeneration of the wash oil, two valves, namely the fifth valve 16 and the sixth valve 18, are installed on the pipeline from the outlet of the regenerator residue tank transfer pump 14 to the wash oil regenerator 19, and the timing of opening the fifth valve 16 and the sixth valve 18 is determined according to actual needs.

[0054] The mechanical clarifying tank 11 is connected to the underground tank 3 to convey part of the residual wash oil to the mechanical clarifying tank 11.

[0055] Furthermore, a second valve 5 is provided on the second pipeline 10 connecting the mechanical clarifying tank 11 and the underground tank transfer pump 4, for controlling the residual wash oil to enter the mechanical clarifying tank 11 from the underground tank 3.

[0056] In the present invention, under normal operation of the system, the first valve 6 is in an open state all the time, so that the residual wash oil collected from the underground tank 3 enters the regenerator residue tank 8; when the wash oil regenerator 19 breaks down and needs to be overhauled, the first valve 6 is closed and the second valve 5 is opened. At this time, the residual wash oil collected from the underground tank 3 directly enters the mechanical clarifying tank 11.

[0057] The mechanical clarifying tank 11 is also connected to the outlet of the regenerator residue tank 8, for heating and separating the residual moisture collected from the residue tank and separating it. The separated moisture (i.e., the supernatant liquid of the mechanical clarifying tank) enters the ammonia distillation system, thereby reducing the light oil in the circulating ammonia water and reducing the operation load of ammonia distillation and biochemical treatment; the separated oil is collected and sold externally after being dehydrated by a super centrifuge. Furthermore, a regenerator residue tank transfer pump 14 is provided between the mechanical clarifying tank 11 and the regenerator residue tank 8, for conveying the residual moisture after heating and separation to the mechanical clarifying tank 11. A third valve 13 and a fourth valve 15 are provided on the third pipeline 12 connecting the mechanical clarifying tank 11 and the regenerator residue tank 8, for controlling the residual moisture to enter the mechanical clarifying tank 11 from the regenerator residue tank 8.

[0058] A system for recycling the wash oil entrained in coal gas provided by the present invention uses a mist eliminator to collect the wash oil entrained in coal gas, obtains the residual wash oil through the mist eliminator water seal and the underground tank, and then directly conveys the residual wash oil to the regenerator residue tank for heating and separation to obtain hot wash oil and residual moisture; the hot wash oil is conveyed to the wash oil regenerator for regeneration and then recycled, and the remaining residual moisture is conveyed to the mechanical clarifying tank for separation and ammonia distillation, reducing the light oil in the circulating ammonia water and reducing the operation load of ammonia distillation and biochemical treatment.

[0059] An embodiment of the present invention provides a system for recycling entrained wash oil in coal gas. On the basis of the existing system for recycling entrained wash oil in coal gas, a first pipeline 7 is added at the outlet of the underground tank transfer pump 4 to pump residual wash oil from the underground tank 3 into the regenerator residue tank 8; a first valve 6 is installed on the first pipeline 7 to control the entry of residual wash oil from the underground tank 3 into the regenerator residue tank 8; a fourth pipeline 17 is added at the outlet of the regenerator residue tank transfer pump 14 to transport the hot wash oil after heating and separation to the wash oil regenerator 19; a fifth valve 16 and a sixth valve 18 are installed on the fourth pipeline 17 to control the entry of hot wash oil from the regenerator residue tank 8 into the wash oil regenerator 19. In this embodiment, a mist eliminator is used to collect the wash oil entrained in the coal gas, and through the mist eliminator water seal and the underground tank collection system, it is directly transported to the regenerator residue tank for heating by the original underground tank pump.

[0060] Operators can monitor the liquid level of residual wash oil collected in the underground tank 3 on the computer screen in the main control room. When the liquid level reaches a certain level, the second valve 5 is closed to prevent residual wash oil from entering the mechanical clarifier 11; the first valve 6 is opened, and the underground tank transfer pump 4 is started to directly transport the residual wash oil collected in the underground tank 3 to the regenerator residue tank 8. After the transportation is completed, the underground tank transfer pump 4 is shut down and the first valve 6 is closed.

[0061] The steam heating valve 9 is opened to heat the residual wash oil to 80°C, and after static separation for 2 hours, the steam heating valve 9 is closed.

[0062] The fourth valve 15 is closed, the regenerator residue tank transfer pump 14 is opened, and the hot wash oil in the regenerator residue tank 8 is transported to the wash oil regenerator 19. The fifth valve 16 and the sixth valve 18 are opened, and the regenerator residue tank transfer pump 14 is started to transport the heated wash oil to the wash oil regenerator 19 for recycling.

[0063] After the transportation is completed, the remaining moisture at the bottom can be transported to the mechanical clarifier 11 for treatment using the original pipeline.

[0064] In this embodiment, by using the system for recycling entrained wash oil in coal gas provided by the present invention, 1 ton of residual wash oil containing 50% water collected every day can be recycled, 0.5 tons of oil can be reduced from entering the mechanical clarifier every day, the oil content in the circulating ammonia water is reduced from 500 mg / L to within 200 mg / L, the COD is reduced from 12000 mg / L to within 8000 mg / L, the entry of light oil into the ammonia distillation system is reduced, and the operating loads of the ammonia distillation and biochemical systems are reduced.

[0065] Meanwhile, by using the recovered and reused system for wash oil mixed in coal gas provided by the present invention, the heating system of the regenerator residue tank can be utilized to heat the residual wash oil at room temperature to above 80°C, reducing the temperature difference from the wash oil regenerator at 190°C. Meanwhile, the moisture in the residual wash oil is removed, improving the operation efficiency of the wash oil regenerator and ensuring efficient operation of wash oil regeneration.

[0066] In addition, by using the wash oil recovery system for wash oil mixed in coal gas provided by the present invention, 0.5 tons of wash oil can be effectively recovered per day, and 180 tons of wash oil can be recovered and reused annually, reducing wash oil consumption.

[0067] A method for recovering and reusing wash oil entrained in coal gas implemented by using the above recovered and reused system provided by the present invention, the method comprising:

[0068] The residual wash oil entrained in the collected coal gas is transported to the regenerator residue tank for heating and standing to achieve water-oil separation, reducing the moisture content in the residual wash oil. After standing, the upper layer is hot wash oil and the lower layer is water (i.e., residual moisture); the hot wash oil is transported to the wash oil regenerator for regeneration and then recovered and reused. Among them, the water content of the residual wash oil can reach 50%.

[0069] In an embodiment of the present invention, the heating temperature of the regenerator residue tank is 75 - 90°C, preferably 80°C; the water content in the hot wash oil is reduced, being 5% - 10%; the oil content ≥ 90%. In this embodiment, the collected residual wash oil is heated and separated to reduce the temperature difference between the residual wash oil directly entering the wash oil regenerator, and at the same time remove most of the moisture in the residual wash oil, ensuring stable operation of the wash oil regenerator.

[0070] In an embodiment of the present invention, the regeneration temperature of the wash oil regenerator is 150 - 200°C. Compared with the phenomenon that the wash oil regenerator vibrates when the regeneration temperature reaches 190°C in the existing process and the wash oil cannot be normally regenerated, in this embodiment, the wash oil regenerator can still operate normally when the regeneration temperature reaches 190°C, the regenerator has no vibration phenomenon, and the wash oil is normally regenerated.

[0071] Furthermore, heating and separating the collected residual wash oil also obtains residual moisture, and the residual water is transported to the mechanical clarifier for separation and then enters the ammonia distillation system, reducing the light oil in the circulating ammonia water and reducing the operation load of ammonia distillation and biochemical treatment.

[0072] In an embodiment of the present invention, in the ammonia distillation system, the oil content of the circulating ammonia water < 200 mg / L, and the COD < 8000 mg / L.

[0073] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A recovery and utilization system for wash oil entrained in coal gas, characterized in that, the system includes: An underground tank for collecting residual wash oil entrained in the coal gas from the debenzolization column; A regenerator residue tank connected to the outlet of the underground tank for heating the residual wash oil from the underground tank; and A wash oil regenerator connected to the outlet of the regenerator residue tank for regenerating the heated residual wash oil; The system further includes a mechanical clarifier, which is connected to the underground tank. A second valve is provided on the second pipeline connecting the underground tank transfer pump and the mechanical clarifier to control the entry of the residual wash oil into the mechanical clarifier; A heating element is provided on the regenerator residue tank for heating the residual wash oil transported to the regenerator residue tank to achieve water-oil separation; The mechanical clarifier is also connected to the outlet of the regenerator residue tank for collecting the residual moisture separated by heating in the regenerator residue tank.

2. The recovery and utilization system according to claim 1, characterized in that, The system further includes: A mist eliminator provided at the gas outlet of the debenzolization column for trapping the residual wash oil entrained in the coal gas.

3. The recovery and utilization system according to claim 2, characterized in that, The system further includes a mist eliminator water seal provided at the liquid outlet of the mist eliminator. The residual wash oil entrained in the coal gas from the debenzolization column is transported to the underground tank through the mist eliminator water seal.

4. The recovery and utilization system according to claim 1, characterized in that, An underground tank transfer pump is provided between the underground tank and the regenerator residue tank for pumping the residual wash oil from the underground tank into the regenerator residue tank.

5. The recovery and utilization system according to claim 4, characterized in that, A first valve is provided on the first pipeline connecting the underground tank transfer pump and the regenerator residue tank to control the entry of the residual wash oil into the regenerator residue tank.

6. The recovery and utilization system according to claim 1, characterized in that, The heating element provides heat through a steam system.

7. The recovery and utilization system according to claim 6, characterized in that, The steam in the steam system is sourced from the steam generated in the chemical production area.

8. A method for recovering and utilizing wash oil entrained in coal gas, characterized in that, It is realized by using the recovery and utilization system according to any one of claims 1-7. The method includes: Transporting the collected residual wash oil entrained in the coal gas to the regenerator residue tank for heating to achieve water-oil separation, reducing the moisture content in the residual wash oil to obtain hot wash oil; transporting the hot wash oil to the wash oil regenerator for regeneration and then recycling.

9. The recovery and utilization method according to claim 8, characterized in that, The heating temperature is 75-90 °C.

10. The recovery and utilization method according to claim 8, characterized in that, The heating temperature is 80 °C.

11. The recovery and utilization method according to claim 8, characterized in that, The oil content in the hot wash oil is ≥90%, and the water content is 5%-10%.

12. The recovery and utilization method according to claim 8, It is characterized in that the regeneration temperature of the wash oil regenerator is 150 - 200 °C.

13. The recycling method according to claim 8, It is characterized in that heating the collected residual wash oil also obtains residual moisture, and the residual moisture is transported to a mechanical clarifying tank for separation and then enters the ammonia distillation system.

14. The recycling method according to claim 13, It is characterized in that in the ammonia distillation system, the oil content of the circulating ammonia water is < 200 mg / L, and the COD is < 8000 mg / L.

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