Pretreatment device for preventing corrosion of waste oil

Abstract

The utility model discloses a pretreatment device for preventing waste oil corrosion, which comprises a vacuum tower, a volatilization line and an anti-corrosion system arranged at the upper end of the vacuum tower, the anti-corrosion system comprises an ammonia injection system, a corrosion inhibitor injection system, a water injection system and a pH value detection system, the ammonia injection system is used for neutralizing condensate water generated in the vacuum tower, and the volatilization line is used for volatilizing the condensate water. The corrosion inhibitor injection system is used for forming a protective film, the corrosion inhibitor injection system works in the ammonia injection system project, the water injection system is used for recycling water resources, and the pH value detection system is used for detecting the value of condensate water; according to the utility model, an ammonia injection system, a corrosion inhibitor injection system and a water injection system are additionally arranged on the vacuum tower top volatilization line of the device, so that the device has the capability of preventing leakage accidents caused by blockage, corrosion and perforation of the tower top volatilization line, water in waste oil can be directly neutralized from acidity to alkalescence, and the waste oil is directly sent to a sewage treatment station, so that the sewage treatment cost is reduced; and economic benefits and safety benefits are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of waste oil pretreatment, in particular to a pretreatment device for preventing waste oil from corrosion. Background Art

[0002] At present, the domestic waste oil pretreatment process basically adopts vacuum distillation. However, the acid value of most waste oils is relatively high. During the vacuum distillation process, as the temperature rises, the pH value of the condensed water from the volatile line at the top of the tower can reach about 2. If effective anti-corrosion measures are not taken, leakage will often occur within a few days, and in serious cases, it may even cause a fire. The performance is particularly prominent on the vacuum volatile line at the top of the vacuum tower. The light components and the vacuumed water are condensed through the volatile line to the condenser, and the water is basically strongly acidic. Even if the condenser and pipeline materials are replaced, the pressure and cost of acidic water to sewage treatment remain high, resulting in poor stability of the device.

[0003] Therefore, we provide a pretreatment device for preventing waste oil from corrosion. Utility Model Content

[0004] The purpose of this utility model is to address the above-mentioned technical problems and provide a pretreatment device for preventing waste oil corrosion. By transforming the process related to the volatilization line of the vacuum tower that is prone to acid corrosion, it can meet production needs, increase the operating time of the device, effectively improve the competitiveness and safety of the enterprise, and achieve the dual goals of economic benefits and accident prevention.

[0005] In view of this, the utility model provides a pretreatment device for preventing waste oil from corrosion, comprising a vacuum tower, a volatilization line, and an anti-corrosion system installed at the upper end of the vacuum tower.

[0006] The anti-corrosion system includes an ammonia injection system, a corrosion inhibitor injection system, a water injection system, and a pH value detection system.

[0007] The ammonia injection system is used to neutralize the condensed water produced in the vacuum tower.

[0008] The corrosion inhibitor injection system is used to form a protective film, and the corrosion inhibitor injection system is located after the ammonia injection system.

[0009] The water injection system is used for recycling water resources.

[0010] The pH value detection system is used to detect the pH value of condensed water.

[0011] Preferably, the ammonia injection system includes an ammonia injection flow pipe, an ammonia injection metering pump, and an ammonia water proportioning tank. The ammonia injection flow pipe is installed on the outside of the volatilization line, and the ammonia injection flow pipe is connected to the inside of the volatilization line. The lower end of the ammonia injection flow pipe is installed at the discharge port of the ammonia injection metering pump, and the ammonia water proportioning tank is installed at the feed port of the ammonia injection metering pump through a pipeline.

[0012] Preferably, the corrosion inhibitor injection system includes a corrosion inhibitor circulation pipe, a diaphragm metering pump, and a corrosion inhibitor proportioning tank. The corrosion inhibitor proportioning tank is installed at the feed port of the diaphragm metering pump through a pipeline, and the corrosion inhibitor circulation pipe is installed at the discharge port of the diaphragm metering pump. The corrosion inhibitor circulation pipe is installed outside the volatilization line, and the corrosion inhibitor circulation pipe is located behind the ammonia injection circulation pipe.

[0013] Preferably, the water injection system includes an injection pipe, a discharge pipe, a condenser, an oil-water separator, and tower top reflux water. The injection pipe is installed outside the volatile line, and the injection pipe is located behind the corrosion inhibitor circulation pipe, and the discharge pipe is connected to the end of the volatile line. The condenser is installed outside the discharge pipe, the oil-water separator is arranged outside the discharge pipe, and the tower top reflux water is arranged at the lower end of the oil-water separator.

[0014] Preferably, the condenser is located between the water injection pipe and the oil-water separator, and the top reflux water and the lower half of the discharge pipe are respectively used to guide the treated water inside the oil-water separator.

[0015] Preferably, the water injection system further includes a circulation pump and a circulation guide pipe, the discharge pipe and the circulation guide pipe are respectively installed at the feed port and the discharge port of the circulation pump, and the other end of the circulation guide pipe is installed at the upper half of the pressure reducing tower.

[0016] Preferably, the pH value detection system includes a pH value detector installed outside the discharge pipe for pH value detection, the pH value detector is located between the water injection pipe and the condenser, and the pH value detector is installed close to the condenser.

[0017] Compared with the prior art, the present invention provides a waste oil corrosion prevention pretreatment device, which has the following beneficial effects:

[0018] The utility model neutralizes hydrogen sulfide and hydrogen chloride components in the volatile line by combining an ammonia injection system with a corrosion inhibitor injection system, and simultaneously forms a water-resistant protective film on the surface of equipment and pipelines to prevent the contact between metal and corrosive water phase.

[0019] The utility model can treat crystals and ammonium salts produced after ammonia and corrosion inhibitor injection in the volatilization line of the vacuum tower in the waste oil pretreatment device through the circulation effect of the water injection system, and prevent the crystals and ammonium salts from accumulating and causing pipeline blockage after long-term use.

[0020] The utility model installs the pH online instrument on the pipeline before the water cooler enters the reflux tank, feeds back the value to the DCS control room through instrument communication, and can timely adjust the injection amount of ammonia water and corrosion inhibitor according to the value.

[0021] The utility model significantly prolongs the service life of the equipment through the transformation of the ammonia injection and corrosion inhibitor injection systems, and extends the maintenance cycle from the original one month to more than one year. Through the thickness measurement of the pipeline equipment during shutdown, the annual corrosion thickness is less than 1mm.

[0022] The utility model improves the sewage treatment capacity from the original 10 tons per day to 25 tons per day through the transformation of the water injection system, and saves 10 tons of fresh water for replenishment per day.

[0023] The parts not involved in the device are the same as those in the prior art or can be implemented by using the prior art. The utility model has a simple structure and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall front view structure of a waste oil corrosion prevention pretreatment device proposed by the utility model;

[0025] Figure 2 This is a schematic diagram of the three-dimensional structure of a corrosion inhibitor injection system of a waste oil corrosion prevention pretreatment device proposed by the utility model;

[0026] Figure 3 This is a schematic diagram of the three-dimensional structure of an ammonia injection system of a waste oil corrosion prevention pretreatment device proposed by the present invention;

[0027] Figure 4 This is a schematic diagram of the three-dimensional structure of a water injection system of a waste oil corrosion prevention pretreatment device proposed by the present invention;

[0028] Figure 5 This is a schematic diagram of the operating flow of a waste oil corrosion prevention pretreatment device proposed by the utility model.

[0029] In the figure: 1. Pressure reducing tower; 2. Volatilization line; 3. Corrosion inhibitor circulation pipe; 4. Diaphragm metering and delivery pump; 5. Corrosion inhibitor proportioning tank; 6. Ammonia injection circulation pipe; 7. Ammonia injection metering pump; 8. Ammonia water proportioning tank; 9. Water injection pipe; 10. Discharge pipe; 11. pH value detector; 12. Condenser; 13. Oil-water separator; 14. Tower top reflux water; 15. Circulation pump; 16. Circulation guide pipe. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0032] Example 1: A pretreatment device for preventing waste oil from corrosion, such as Figure 1 - Figure 5 As shown, it includes a vacuum tower 1, a volatilization line 2, and an anti-corrosion system installed at the upper end of the vacuum tower 1.

[0033] The anti-corrosion system includes an ammonia injection system, a corrosion inhibitor injection system, a water injection system, and a pH value detection system.

[0034] The ammonia injection system is used to neutralize the condensed water produced in the vacuum tower 1.

[0035] The corrosion inhibitor injection system is used to form a protective film, and the corrosion inhibitor injection system is located after the ammonia injection system.

[0036] The water injection system is used to recycle water resources.

[0037] The pH value detection system is used to detect the pH value of condensed water.

[0038] Based on the combined use of the ammonia injection system, the corrosion inhibitor injection system, the water injection system, and the pH value detection system in the anti-corrosion system, ammonia injection for neutralization, corrosion inhibitor injection for protection, and water injection for circulation can be carried out during the circulation of condensed water inside the vacuum tower 1, so that the device has the ability to neutralize the acidity of the condensed water before continuing to circulate, form a protective film on the inner wall of the pipeline, and recycle the neutralized water flow, thereby improving the safety and stability of the device during production and use. At the same time, under the real-time monitoring of the pH value detection system, timely detection is carried out according to the pH value of the neutralized condensed water, which is convenient for precise adjustment of the concentrations in the ammonia injection system and the corrosion inhibitor injection system, so that the device has the effect of long-term stable use.

[0039] like Figure 1 - Figure 5As shown, the ammonia injection system includes an ammonia injection flow pipe 6, an ammonia injection metering pump 7, and an ammonia water proportioning tank 8. The ammonia injection flow pipe 6 is installed on the outside of the volatilization line 2, and the ammonia injection flow pipe 6 is connected to the inside of the volatilization line 2. The lower end of the ammonia injection flow pipe 6 is installed at the discharge port of the ammonia injection metering pump 7, and the ammonia water proportioning tank 8 is installed at the feed port of the ammonia injection metering pump 7 through a pipeline.

[0040] With the combined use of the ammonia injection metering pump 7 and the ammonia water proportioning tank 8, and with the support of the diversion of the ammonia injection flow pipe 6, the ammonia water is prepared into a 5% concentration of the corrosion inhibitor proportioning tank and injected into the top of the volatilization line 2 by the ammonia injection metering pump 7, which can neutralize the acidity of the condensed water inside to a weak base, thereby reducing its corrosion intensity.

[0041] like Figure 1 - Figure 5 As shown, the corrosion inhibitor injection system includes a corrosion inhibitor circulation pipe 3, a diaphragm metering pump 4, and a corrosion inhibitor proportioning tank 5. The corrosion inhibitor proportioning tank 5 is installed at the feed port of the diaphragm metering pump 4 through a pipeline, and the corrosion inhibitor circulation pipe 3 is installed at the discharge port of the diaphragm metering pump 4. The corrosion inhibitor circulation pipe 3 is installed outside the volatilization line 2, and the corrosion inhibitor circulation pipe 3 is located behind the ammonia injection circulation pipe 6.

[0042] With the combined use of the corrosion inhibitor proportioning tank 5 and the diaphragm metering delivery pump 4, and with the support of the flow diversion of the corrosion inhibitor circulation pipe 3, the corrosion inhibitor is mixed with pure water to a concentration of 10%, a ratio of 40ppm / ton of oil, and then injected into the rear end of the ammonia inlet by the diaphragm metering delivery pump 4. Under the action of the corrosion inhibitor, a protective film is formed to prevent direct contact between the pipeline and the condensed water.

[0043] Example 2: A pretreatment device for preventing waste oil from corrosion, such as Figure 1 - Figure 5 As shown, the water injection system includes a water injection pipe 9, a discharge pipe 10, a condenser 12, an oil-water separator 13, and a tower top reflux water 14. The water injection pipe 9 is installed on the outside of the volatilization line 2, and the water injection pipe 9 is located behind the corrosion inhibitor circulation pipe 3, and the discharge pipe 10 is connected to the end of the volatilization line 2, the condenser 12 is installed on the outside of the discharge pipe 10, the oil-water separator 13 is arranged on the outside of the discharge pipe 10, and the tower top reflux water 14 is arranged at the lower end of the oil-water separator 13.

[0044] The condenser 12 is located between the water injection pipe 9 and the oil-water separator 13 , and the top reflux water 14 and the lower half of the discharge pipe 10 are used to guide the treated water inside the oil-water separator 13 .

[0045] The water injection system also includes a circulation pump 15 and a circulation guide pipe 16. The discharge pipe 10 and the circulation guide pipe 16 are respectively installed at the feed port and the discharge port of the circulation pump 15. The other end of the circulation guide pipe 16 is installed at the upper half of the vacuum tower 1.

[0046] Based on the guidance of the discharge pipe 10, the cleaning and adsorption of the oil-water separator 13, and the operation of the circulation pump 15, the neutral condensed water after the injection of ammonia and corrosion inhibitor can be returned to the volatile line 2, which can effectively replace the use of fresh water. In addition, when the ratio of ammonia water and corrosion inhibitor is unbalanced, the pH value can be adjusted by returning the condensed water to the volatile line 2, thereby improving the diversity of its reuse.

[0047] like Figure 1 - Figure 5 As shown, the pH detection system includes a pH detector 11 installed outside the discharge pipe 10 for pH detection. The pH detector 11 is located between the water injection pipe 9 and the condenser 12, and the pH detector 11 is installed close to the condenser 12.

[0048] First, by installing the pH value detector 11 before the condenser 12 and the oil-water separator 13 pipeline, the value is fed back to the DCS control room through the communication of the pH value detector 11, and the injection amount of ammonia water and corrosion inhibitor can be adjusted in time according to the value. In addition, the pH value detector 11 is installed before the condenser 12, which effectively prevents the pH value of the condensed water at the original detection equipment from volatilizing to the condenser 12 and then passing through the reflux tank, causing the detection data to lag, resulting in a large error between the pH value at the original detection equipment and the pH value of the system equipment.

[0049] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A waste oil corrosion prevention pretreatment device, comprising a vacuum tower (1), a volatilization line (2), and an anti-corrosion system installed at the upper end of the vacuum tower (1), characterized in that: The anti-corrosion system includes an ammonia injection system, a corrosion inhibitor injection system, a water injection system, and a pH value detection system; The ammonia injection system is used to neutralize the condensed water produced in the vacuum tower (1); The corrosion inhibitor injection system is used to form a protective film, and the corrosion inhibitor injection system is located after the ammonia injection system; The water injection system is used for recycling water resources; The pH value detection system is used to detect the pH value of condensed water.

2. The waste oil corrosion prevention pretreatment device according to claim 1, characterized in that: The ammonia injection system comprises an ammonia injection flow pipe (6), an ammonia injection metering pump (7), and an ammonia water proportioning tank (8). The ammonia injection flow pipe (6) is installed outside the volatilization line (2), and the ammonia injection flow pipe (6) is communicated with the inside of the volatilization line (2). The lower end of the ammonia injection flow pipe (6) is installed at the discharge port of the ammonia injection metering pump (7), and the ammonia water proportioning tank (8) is installed at the feed port of the ammonia injection metering pump (7) through a pipeline.

3. The waste oil corrosion prevention pretreatment device according to claim 2, characterized in that: The corrosion inhibitor injection system comprises a corrosion inhibitor circulation pipe (3), a diaphragm metering delivery pump (4), and a corrosion inhibitor proportioning tank (5). The corrosion inhibitor proportioning tank (5) is installed at the feed port of the diaphragm metering delivery pump (4) through a pipeline, the corrosion inhibitor circulation pipe (3) is installed at the discharge port of the diaphragm metering delivery pump (4), and the corrosion inhibitor circulation pipe (3) is installed outside the volatilization line (2), and the corrosion inhibitor circulation pipe (3) is located behind the ammonia injection circulation pipe (6).

4. The waste oil corrosion prevention pretreatment device according to claim 3, characterized in that: The water injection system comprises a water injection pipe (9), a discharge pipe (10), a condenser (12), an oil-water separator (13), and tower top reflux water (14). The water injection pipe (9) is installed outside the volatile line (2), and the water injection pipe (9) is located behind the corrosion inhibitor circulation pipe (3). The discharge pipe (10) is connected to the end of the volatile line (2). The condenser (12) is installed outside the discharge pipe (10), the oil-water separator (13) is arranged outside the discharge pipe (10), and the tower top reflux water (14) is arranged at the lower end of the oil-water separator (13).

5. The waste oil corrosion prevention pretreatment device according to claim 4, characterized in that: The condenser (12) is located between the water injection pipe (9) and the oil-water separator (13), and the top reflux water (14) and the lower half of the discharge pipe (10) are respectively used to guide the treated water inside the oil-water separator (13).

6. The waste oil corrosion prevention pretreatment device according to claim 4, characterized in that: The water injection system further comprises a circulation pump (15) and a circulation guide pipe (16). The discharge pipe (10) and the circulation guide pipe (16) are respectively installed at the feed port and the discharge port of the circulation pump (15). The other end of the circulation guide pipe (16) is installed at the upper half of the pressure reducing tower (1).

7. The waste oil corrosion prevention pretreatment device according to claim 6, characterized in that: The pH value detection system comprises a pH value detector (11) installed outside the discharge pipe (10) for pH value detection. The pH value detector (11) is located between the water injection pipe (9) and the condenser (12), and the pH value detector (11) is installed close to the condenser (12).

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