Comprehensive waste gas recycling system for oil processing pretreatment workshop

Abstract

The utility model discloses an oil processing pretreatment workshop waste gas comprehensive recycling system which comprises a cyclone separator I, a cyclone separator II, a cyclone separator III and a cyclone separator IV, the pulse bag-type dust collector is connected with the low-moisture waste gas; a gas inlet of the waste gas heater is connected with outlets of the cyclone dust collector I and the cloth bag dust collector; a lower air inlet of the turning plate cooler is connected with an air outlet of the waste gas heater; an inlet of the cyclone II is connected with an air outlet in the upper part of the turning plate; an air inlet of the water washing tower is connected with an outlet of the cyclone II; an air inlet of the water-steam separator is connected with an air outlet of the water washing tower, an air outlet is communicated with the atmosphere, a bottom outlet is connected with a first heating section tube pass inlet of the waste gas heater through a circulating pump, and a first heating section tube pass outlet is connected with an upper spraying opening of the water washing tower; a bottom outlet of the flash tank is connected with a second heating section tube pass inlet of the waste gas heater, and a second heating section tube pass outlet of the waste gas heater is connected with the condensate water collecting pipe. The system makes full use of waste heat of waste gas, saves energy, reduces emission and reduces equipment investment.

Description

Technical Field

[0001] The utility model relates to an exhaust gas treatment system for an oil processing pretreatment workshop, in particular to a comprehensive reuse system for exhaust gas in an oil processing pretreatment workshop, belonging to the technical field of waste heat utilization. Background Art

[0002] In the field of oil processing, the pretreatment leaching process is one of the most common methods. The oil seeds can be divided into cleaning, conditioning, crushing, hulling, rolling, puffing, cooling, steaming and frying, pressing and other sections in the pretreatment stage. A large amount of dust-containing exhaust gas will be generated in each section. Among them, the dust-containing exhaust gas generated in sections such as conditioning, crushing, rolling and pressing also contains a large amount of water vapor and low-grade waste heat. According to experience, the temperature of the exhaust gas generated in these sections is generally between 50 and 65 °C. Usually, these exhaust gases are directly discharged into the atmosphere through the outlets of their respective fans. At the same time, a large amount of secondary flash steam of high-pressure condensate water will be precipitated in the oil pretreatment workshop and directly discharged into the atmosphere nearby through the exhaust pipe. This not only causes waste of heat energy, but also increases the emission of air pollutants.

[0003] In addition, in the oil processing pretreatment workshop, in the cooling section, hot air with a temperature of about 60-80 °C is introduced into the cooler to conduct countercurrent evaporation heat absorption with the high-temperature material with a temperature of about 100-110 °C entering the cooler, so as to achieve the purpose of reducing the temperature of the material. Usually, the hot air introduced into the cooler is fresh air heated by an exhaust gas heater. The heat source of the exhaust gas heater is generally saturated steam. Continuous production will cause enterprises to continuously invest costs and consume a large amount of steam energy.

[0004] The above problems existing in the oil processing pretreatment workshop are contrary to the national energy conservation and emission reduction plans and goals. Therefore, in order to meet the environmental protection standards, enterprises need to purchase advanced exhaust gas treatment equipment to collect and purify these exhaust gases in the pretreatment workshop. High costs will be generated in aspects such as equipment investment, installation and maintenance. Moreover, such a large volume of exhaust gas in the pretreatment workshop requires more powerful tail gas treatment equipment, further increasing the cost investment. At the same time, the multi-point and diversified emission of exhaust gas in the pretreatment workshop is also one of the pain points and difficulties for enterprises to conduct tail gas treatment. Different tail gas treatment technologies need to be adopted, which is difficult to maximize the utilization of exhaust gas, and the cost is high and the maintenance cost is large.

[0005] In order to implement the regulations on the emission of exhaust gas in the "Environmental Protection Law of the People's Republic of China", the "Atmospheric Pollution Prevention and Control Law of the People's Republic of China" and the "Integrated Emission Standard of Air Pollutants" (GB16297-1996), "Technical Method for Formulating Local Air Pollutant Emission Standards" (GB / T13201-91), the utility model patent designs a new comprehensive reuse system for exhaust gas in an oil processing pretreatment workshop. Content of the Utility Model

[0006] The purpose of this section is to outline some aspects of the embodiments of the present utility model and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract of the specification and the title of the utility model of this application, and such simplifications or omissions shall not be used to limit the scope of the present utility model.

[0007] In view of the above and / or problems existing in the prior art, the present utility model is proposed.

[0008] The purpose of the present utility model is to provide a comprehensive waste gas recycling system for the waste gas in the oil processing pretreatment workshop, which can solve the problem of waste gas emission during the oil pretreatment process, and at the same time make full use of the low-grade waste heat in the waste gas, reduce waste gas emissions, reduce energy consumption, and reduce equipment investment costs and operating costs.

[0009] To solve the above technical problems, a comprehensive waste gas recycling system for the waste gas in the oil processing pretreatment workshop of the present utility model includes:

[0010] Cyclone I, the inlet is connected to the discharge port of the high-moisture waste gas, and the outlet is connected to the inlet of Centrifugal Fan I;

[0011] Pulse bag filter, the inlet is connected to the discharge port of the low-moisture waste gas, and the outlet is connected to the inlet of Centrifugal Fan II;

[0012] Waste gas heater, which is successively provided with a first heating section and a second heating section along the gas flow direction, and the air inlet is connected to the outlets of the Centrifugal Fan I and Centrifugal Fan II;

[0013] Flap cooler, the upper part is the high-temperature material inlet, the bottom is the low-temperature material outlet, and the air inlet on the lower side wall is connected to the air outlet of the waste gas heater;

[0014] Cyclone II, the inlet is connected to the upper side wall air outlet of the flap cooler, and the outlet is connected to the inlet of Centrifugal Fan III;

[0015] Water scrubber, the air inlet is connected to the outlet of the Centrifugal Fan III, the air outlet is connected to the inlet of Centrifugal Fan IV, the bottom outlet is connected to the inlet of the circulation pump, the outlet of the circulation pump is connected to the inlet of the first heating section tube side of the waste gas heater, and the outlet of the first heating section tube side of the waste gas heater is connected to the upper spray port of the water scrubber through a circulation pipe;

[0016] Water vapor separator, the air inlet is connected to the outlet of the Centrifugal Fan IV, the exhaust port is vented to the atmosphere, and the liquid phase outlet is connected to the reflux port of the water scrubber;

[0017] Flash tank, the inlet is connected to the outlet of the steam condensate pipe, the bottom outlet is connected to the inlet of the second heating section tube side of the waste gas heater, and the outlet of the second heating section tube side of the waste gas heater is connected to the condensate water collection pipe.

[0018] As an improvement of the present utility model, the secondary steam outlet of the flash tank is connected to the outlet air duct of the third centrifugal fan through a flash vapor phase pipe.

[0019] As a further improvement of the present utility model, a makeup air inlet for fresh air is provided on the pipe wall of the flash vapor phase pipe.

[0020] As a further improvement of the present utility model, a partition extending downward is provided in the middle of the top wall of the water washing tower. The partition divides the inner cavity of the water washing tower into left and right chambers that communicate with each other at the bottom. A packing layer is provided in the middle of the left chamber, the spray pipe is located above the packing layer, the air inlet of the water washing tower is located at the top of the left chamber, and the air outlet of the water washing tower is located at the top of the right chamber.

[0021] As a further improvement of the present utility model, the discharge ports of the first cyclone, the second cyclone and the pulse bag filter are respectively connected to the production system through air locks.

[0022] Compared with the prior art, the present utility model has achieved the following beneficial effects: 1. Solve the problem of discharging hot and dusty waste gas during the oil pretreatment process, and avoid the generation of different types of waste gas in multiple sections of the pretreatment workshop in the oil processing industry, which requires designing multiple sets of waste gas discharge systems that meet environmental protection requirements. The total amount of waste gas discharged from each section of the oil pretreatment workshop is large, and it is required that the tail gas treatment and environmental protection equipment have the corresponding ability to handle a large air volume. This system greatly reduces the equipment investment cost and the later maintenance cost.

[0023] 2. This system comprehensively utilizes different types of waste gas in different sections of the pretreatment workshop, introduces the waste gas containing materials and waste heat in these sections into the equipment of another energy-consuming section to replace the heated fresh air, fully utilizes the low-grade waste heat in the waste gas, and achieves the reduction of waste gas emissions and the reduction of operating energy consumption. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. The drawings are only for reference and explanation, and are not used to limit the present utility model. Among them:

[0025] Figure 1 It is a flowchart of the waste gas comprehensive recycling system for the oil processing pretreatment workshop of the present utility model;

[0026] In the figure: 1. Cyclone I; 2. Centrifugal fan I; 3. Air lock I; 4. Pulse bag filter; 5. Centrifugal fan II; 6. Air lock II; 7. Flash tank; 8. Exhaust gas heater; 9. Flap cooler; 10. Cyclone II; 11. Air lock III; 12. Centrifugal fan III; 13. Water scrubber; 14. Circulation pump; 15. Centrifugal fan IV; 16. Water-vapor separator. Detailed implementation manners

[0027] In the following description of the present utility model, the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating that the device must have a specific orientation.

[0028] In order to make the technical means, creative features, achieved purposes and effects realized by the present utility model easy to understand, the present utility model will be further described below with reference to specific drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present utility model belongs. The terms used in the description of the present utility model herein are only for the purpose of describing specific embodiments, and are not intended to limit the present utility model.

[0030] As Figure 1 shown, the waste gas comprehensive recycling system for the oil processing pretreatment workshop of the present utility model includes Cyclone I 1, Centrifugal fan I 2, Air lock I 3, Pulse bag filter 4, Centrifugal fan II 5, Air lock II 6, Flash tank 7, Exhaust gas heater 8, Flap cooler 9, Cyclone II 10, Air lock III 11, Centrifugal fan III 12, Water scrubber 13, Circulation pump 14, Centrifugal fan IV 15 and Water-vapor separator 16.

[0031] The discharge port of the high-moisture-content waste gas is connected to the inlet of Cyclone-1, and the discharge port of the low-moisture-content waste gas is connected to the air inlet of the pulse bag filter 4. The outlet of Cyclone-1 is connected to the suction port of the centrifugal fan-2 through an air duct, and the outlet of the pulse bag filter 4 is connected to the suction port of the centrifugal fan-5 through an air duct. The outlets of the centrifugal fan-2 and the centrifugal fan-5 are connected to the air inlet of the waste gas heater 8 through an air duct. The waste gas heater 8 is successively provided with a first heating section and a second heating section along the gas flow direction. The outlet of the waste gas heater 8 is connected to the air inlet of the flap cooler 9 through an air duct. The upper part of the flap cooler 9 is the high-temperature material inlet, and the bottom is the low-temperature material outlet. The heated waste gas enters the flap cooler 9 to supply air and cool the high-temperature material at 100 - 110 °C, so as to prevent the water evaporated from the high-temperature material in the flap cooler 9 from re-condensing. The waste gas from each section of the pretreatment workshop is comprehensively utilized to replace the fresh hot air required for the operation of the flap cooler in the cooling section, reducing the waste gas emission points and emission volume in the production system, and at the same time reducing the energy consumption of the air heater. In the flap cooler 9, the hot waste gas flows countercurrently from bottom to top through the high-temperature material, taking away the moisture and heat of the material and forming a high-humidity dust-containing hot waste gas with a temperature of about 60 - 75 °C.

[0032] The outlet of the flap cooler 9 is connected to the inlet of Cyclone-2 10 through an air duct, and the outlet of Cyclone-2 10 is connected to the suction port of the centrifugal fan-12 through an air duct. The outlet of the centrifugal fan-12 is connected to the inlet of the water scrubber 13 through an air duct. The outlet of the water scrubber 13 is connected to the suction port of the centrifugal fan-15 through an air duct. The outlet of the centrifugal fan-15 is connected to the inlet of the water-vapor separator 16, and the outlet of the water-vapor separator 16 is connected to the atmosphere.

[0033] In the middle of the top wall of the water scrubber 13, there is a partition extending downward. The partition divides the inner cavity of the water scrubber into left and right chambers that communicate at the bottom. In the middle of the left chamber, there is a packing layer. The spray pipe is located above the packing layer. The air inlet of the water scrubber is located at the top of the left chamber, and the air outlet of the water scrubber is located at the top of the right chamber.

[0034] The water outlet of the water-vapor separator 16 is connected to the water return port of the water scrubber 13. The water outlet of the water scrubber 13 is connected to the suction port of the circulation pump 14. The outlet of the circulation pump 14 is connected to the water inlet of the first heating section tube pass of the waste gas heater 8. The water outlet of the first heating section tube pass of the waste gas heater 8 is connected to the spray water inlet of the water scrubber 13 through a circulation pipe. The water inlet of the flash tank 7 is connected to the high-pressure condensate water of the production system. The water outlet of the flash tank 7 is connected to the water inlet of the second heating section tube pass of the waste gas heater 8. The water outlet of the second heating section tube pass of the waste gas heater 8 is connected to the production system; the top gas outlet of the flash tank 7 is connected to the air inlet of the water scrubber 13 through a flash gas phase pipe, and a fresh air supply port is provided on the side wall of the flash gas phase pipe for supplementing fresh air.

[0035] During operation, the exhaust gas to be filtered enters the cyclone - 1 and the pulse bag filter 4 for dust removal. Multiple cyclones and pulse bag filters can be added according to the working conditions of the workshop. The exhaust gas with low humidity is treated by the pulse bag filter 4 to avoid the adhesion of dust on the surface of the filter bags. The dust and dander separated from the exhaust gas by the cyclone - 1 enter the feed port of the airtight feeder - 3 through the dust discharge port of the cyclone - 1, and the dust and dander discharged from the discharge port of the airtight feeder - 3 return to the original production system; the dust and dander separated from the exhaust gas by the pulse bag filter 4 enter the feed port of the airtight feeder - 6 through the dust discharge port of the pulse bag filter 4, and the dust and dander discharged from the discharge port of the airtight feeder - 6 return to the original production system.

[0036] The exhaust gas after dust removal by the cyclone - 1 enters the centrifugal fan - 2 through the air duct, and the exhaust gas after dust removal by the pulse bag filter 4 enters the centrifugal fan - 5 through the air duct. Under the boost of the centrifugal fan - 2 and the centrifugal fan - 5, the exhaust gas enters the exhaust gas heater 8 through the air duct and becomes hot exhaust gas after being heated by the exhaust gas heater 8. The hot exhaust gas enters the lower air inlet of the flap cooler 9 through the air duct. In the flap cooler 9, the hot exhaust gas flows counter - currently to the material from bottom to top and conducts sufficient heat exchange, causing the moisture on the surface of the material to evaporate and absorbing the heat of the material. Eventually, the temperature of the material gradually decreases. The hot exhaust gas takes away the moisture in the flap cooler 9 and forms high - humidity dust - containing exhaust gas, which is discharged from the air outlet of the flap cooler 9 and enters the air inlet of the cyclone - 2 10. Through centrifugal separation, the dust and dander in the hot and humid exhaust gas tightly adhere to the inner wall of the cyclone - 2 10 and descend along the inner wall to the discharge port, and then enter the airtight feeder - 3 11 through the pipeline. Finally, the dust and dander in the hot and humid exhaust gas are discharged from the discharge port of the airtight feeder - 3 11 to the original production system for recycling.

[0037] The separated hot and humid exhaust gas enters the centrifugal fan - 3 12 through the air duct. Under the boost of the centrifugal fan - 3 12, it enters the water scrubber 13 from top to bottom through the air duct. The spraying device of the water scrubber 13 fills the tower with water in the form of fine droplets evenly, forming a large - area water mist. These water mists also spray from top to bottom, in the same direction as the air flow. After passing through the packing layer and continuing to flow downward in a folded manner, they enter the right chamber. Through the sedimentation effect in the right chamber, the entrainment of droplets in the exhaust air is reduced.

[0038] The packing in the water scrubber 13 enables the hot and humid waste gas to come into full contact with the water mist, facilitating heat exchange between the hot and humid waste gas and water, and gradually reducing the temperature of the hot and humid waste gas to become wet waste gas. Meanwhile, the baffle plate in the water scrubber 13 enables the wet waste gas to change its flow direction and be discharged from the water scrubber 13 from bottom to top, and part of the water mist entrained in the wet waste gas falls into the circulating water stored at the bottom of the water scrubber 13 under the action of gravity. Finally, the wet waste gas with a small amount of water vapor enters the fourth centrifugal fan 15 from the air outlet of the water scrubber 13, and enters the water vapor separator 16 through the air duct under the boosting of the fourth centrifugal fan 15. After the entrained water is recovered by centrifugal separation in the water vapor separator 16, the dried waste gas is finally discharged into the atmosphere through the air outlet of the water vapor separator 16, and the recovered entrained water returns to the water scrubber 13 through the drain outlet of the water vapor separator 16, thereby reducing the water consumption of the water scrubber. The water outlet of the water scrubber 13 enters the circulating pump 14 through the water outlet pipe, and the water discharged from the circulating pump 14 enters the tube side of the first heating section of the waste gas heater 8, and returns to the spray nozzle of the water scrubber 13 for circulating spraying after heat exchange.

[0039] The high-pressure condensate from the production system enters the flash tank 7. In the flash tank 7, part of the condensate flashes into secondary steam and is discharged from the air outlet and enters the air inlet of the water scrubber 13 through the air duct. An air supply port is reserved on this air duct for air supply. The remaining low-pressure condensate in the flash tank 7 enters the second heating section of the waste gas heater, and the condensate after heat exchange returns to the production system.

[0040] The above is only the preferred and feasible embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention. It does not limit the patent protection scope of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. Except for the above embodiments, without departing from the spirit and scope of the present invention, the present invention may have other implementation manners. The present invention will also have various changes and improvements. Any technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope required by the present invention. The protection scope required by the present invention is defined by the appended claims and their equivalents. The technical features not described in the present invention can be realized by or adopted from the prior art, and will not be elaborated here.

Claims

1. An integrated waste gas recycling system for an oil processing pretreatment workshop, characterized in that, Including: Cyclone 1, with its inlet connected to the discharge port of the high-moisture waste gas and its outlet connected to the inlet of Centrifugal Fan 1; Pulse bag filter, with its inlet connected to the discharge port of the low-moisture waste gas and its outlet connected to the inlet of Centrifugal Fan 2; Waste gas heater, successively provided with a first heating section and a second heating section along the gas flow direction, and its air inlet connected to the outlets of the Centrifugal Fan 1 and Centrifugal Fan 2; Flap cooler, with its upper part as the high-temperature material inlet, its bottom as the low-temperature material outlet, and the air inlet on the lower side wall connected to the air outlet of the waste gas heater; Cyclone 2, with its inlet connected to the upper side wall air outlet of the flap cooler and its outlet connected to the inlet of Centrifugal Fan 3; Water scrubber, with its air inlet connected to the outlet of Centrifugal Fan 3, its air outlet connected to the inlet of Centrifugal Fan 4, its bottom outlet connected to the inlet of the circulation pump, the outlet of the circulation pump connected to the tube side inlet of the first heating section of the waste gas heater, and the tube side outlet of the first heating section of the waste gas heater connected to the upper spray port of the water scrubber through a circulation pipe; Water vapor separator, with its air inlet connected to the outlet of Centrifugal Fan 4, its exhaust port vented to the atmosphere, and its liquid phase outlet connected to the reflux port of the water scrubber; Flash tank, with its inlet connected to the outlet of the steam condensate pipe, its bottom outlet connected to the tube side inlet of the second heating section of the waste gas heater, and the tube side outlet of the second heating section of the waste gas heater connected to the condensate water collection pipe.

2. The waste gas comprehensive recycling system for the oil processing pretreatment workshop according to claim 1, wherein: The secondary steam outlet of the flash tank is connected to the outlet air duct of Centrifugal Fan 3 through a flash vapor phase pipe.

3. The waste gas comprehensive recycling system for the oil processing pretreatment workshop according to claim 2, wherein: The wall of the flash vapor phase pipe is provided with a fresh air make-up port.

4. The waste gas comprehensive recycling system for the oil processing pretreatment workshop according to claim 2, characterized in that: In the middle of the top wall of the water scrubber, there is a partition extending downward. The partition divides the inner cavity of the water scrubber into left and right chambers with a common bottom. In the middle of the left chamber, there is a packing layer. The spray pipe is located above the packing layer. The air inlet of the water scrubber is located at the top of the left chamber, and the air outlet of the water scrubber is located at the top of the right chamber.

5. The comprehensive recycling system for waste gas in the oil processing pretreatment workshop according to any one of claims 1 to 4, characterized in that: The discharge ports of the Cyclone 1, Cyclone 2 and pulse bag filter are respectively connected to the production system through airtight conveyors.

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