Waste heat recycling system for evapo-separated machine in vegetable oil factory

Abstract

The utility model belongs to the field of vegetable oil leaching oil production waste heat recovery, and discloses a vegetable oil factory evapo-separated machine waste heat recycling system which comprises a DT, a fin heater, a fan, a trapping tank, a trapping pump, a falling film evaporator, a flash tank, a circulating pump, a heat exchanger, a steam-jet pump, a steam-water separator, an energy-saving tank, an energy-saving pump and an extractor. On the basis of the prior art, a new device system is additionally arranged on a DT energy-saving layer of the evapo-separated machine, gas heat is recycled, heat exchange media are heated through high-temperature waste heat, and the problems that when the DT energy-saving layer of the evapo-separated machine recycles heat in a steam injection mode, the recycling rate is low, heat energy cannot be effectively utilized, and the energy consumption is low are solved. The DT direct steam usage amount of the evapo-separated machine is reduced, and the heat recycling rate is increased.

Description

Technical Field

[0001] This utility model application relates to a waste heat recovery and reuse system for a vegetable oil plant evaporator, belonging to the field of waste heat recovery in vegetable oil extraction. Background Technology

[0002] Because the extraction and production of vegetable oils requires the use of steam to separate solvents from materials, and steam consumption accounts for a significant proportion of processing costs, reducing steam consumption has always been a key focus in the vegetable oil extraction and processing industry. The wet meal entering the desolventizer (DT) contains 20-35% solvent, which needs to be removed using both indirect and direct steam. Generally, direct steam at a pressure below 0.1 MPa and indirect steam at a pressure of 0.7-1.0 MPa are used. During the desolventizing process, the direct steam provides heat and condenses, absorbing moisture into the meal, typically reaching 16-19%. The hot meal exiting the desolventizer enters the drying and cooling unit (DC), where the DC reduces the moisture content from 16%-19% to approximately 12.5% ​​and lowers the meal temperature to below 40°C. The drying and cooling unit uses air as the drying medium; the hot air carries away the moisture, achieving the drying purpose. The initial hot air temperature in the drying and cooling unit is 80-95°C, with a relative humidity of 60-80%, releasing a large amount of heat during cooling, which has high utilization value. Currently, there are two main methods for recovering and utilizing the first-stage hot air in a DC drying cooler: One method uses a plate heat exchanger for heat recovery, with the first-stage hot air on the hot side and the incoming cold air on the cold side. The drawback of this method is insufficient heat recovery; the cold air can be heated to around 70℃, saving only 10 kg of steam per ton of soybeans. The other method uses a falling film evaporator to heat soft water and generate low-pressure steam. The water flows through the tubes, while the first-stage hot air flows through the shell. The hot air after passing through the falling film evaporator then exchanges heat with the soft water and the cold air in the drying cooler. The drawback of this method is a small temperature difference in heat transfer between the first-stage hot air and the cold air in the drying cooler; saving only 15 kg of steam per ton of soybeans.

[0003] Therefore, it is necessary to propose a waste heat recovery and reuse system for vegetable oil desiccant to solve the above-mentioned technical problems. Summary of the Invention

[0004] To address the problem of insufficient heat recovery in the first-stage hot air recovery and utilization of a drying and cooling machine, this application provides a waste heat recovery and reuse system for a vegetable oil plant's evaporator.

[0005] The technical solution adopted in this application is:

[0006] A waste heat recovery and reuse system for a vegetable oil plant evaporator includes a DT (Distillation Tank), a finned heater, a fan, a collection tank, a collection pump, a falling film evaporator, a flash tank, a circulating pump, a heat exchanger, a steam jet pump, a steam-water separator, an energy-saving tank, an energy-saving pump, and an extractor.

[0007] The finned heater is provided with a fan inlet, two finned heater outlets, a heat exchange inlet, and one finned heater outlet.

[0008] The fan inlet is connected to the fan outlet; the second outlet of the finned heater is connected to the energy-saving inlet of the energy-saving tank.

[0009] The outlet of the finned heater is connected to the bottom of the DT, and the outlet of the DT is connected to the collection tank; the top outlet of the collection tank is connected to the lower inlet of the falling film evaporator via a pipeline; the lower outlet of the falling film evaporator is connected to the side port of the flash tank; the lower port of the flash tank is connected to the upper inlet of the falling film evaporator via a circulation pump; the upper port of the flash tank is connected to the steam jet pump; and the lower port of the collection tank is connected to the collection pump.

[0010] The upper outlet end of the falling film evaporator is connected to the heat exchanger via a pipeline; the heat exchanger includes a first inlet end, a second inlet end, a first outlet end, and a second outlet end; the second outlet end of the heat exchanger is connected to the heat exchange inlet of the finned heater via a pipeline.

[0011] The steam jet pump is connected to the DT energy-saving layer via a pipeline through a steam-water separator.

[0012] Furthermore, the energy-saving tank is connected to the leachater via a pipeline and an energy-saving pump, and the leachater is connected to a spray head installed inside the energy-saving tank via a pipeline.

[0013] This application has the following beneficial effects:

[0014] This application proposes a waste heat recovery and reuse system for a vegetable oil plant evaporator. Based on existing technology, a new device system is added to the DT energy-saving layer of the evaporator to recover gas heat and use the high-temperature waste heat to heat the heat exchange medium. This solves the problems of low recovery and utilization rate, ineffective heat energy utilization, and large waste of waste heat when using steam injection to recover heat in the DT energy-saving layer of the evaporator. It saves the direct steam usage of the DT of the evaporator and improves the heat recovery and utilization rate. The overall steam saving is 25 kg / ton of material, resulting in significant economic benefits. Attached Figure Description

[0015] Figure 1 A schematic diagram of a waste heat recovery and reuse system for a vegetable oil mill's vaporizer.

[0016] In the diagram: 1. DT, 2. Flange heater, 21. Fan inlet, 22. Flange heater outlet 2, 23. Heat exchange inlet, 24. Flange heater outlet 1, 3. Fan, 4. Collection tank, 5. Collection pump, 6. Falling film evaporator, 7. Flash tank, 8. Circulation pump, 9. Heat exchanger, 10. Steam jet pump, 11. Steam-water separator, 12. Energy-saving tank, 13. Energy-saving pump, 14. Immersion tank. Detailed Implementation

[0017] The present application will now be described in detail with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present application. Furthermore, descriptions of structures and techniques that are generally known are omitted in the following description to avoid unnecessarily obscuring the concepts of the present application.

[0018] Example: Referring to the accompanying drawings, this application discloses a waste heat recovery and reuse system for a vegetable oil plant evaporator, including DT1, finned heater 2, fan 3, collection tank 4, collection pump 5, falling film evaporator 6, flash tank 7, circulating pump 8, heat exchanger 9, steam jet pump 10, steam-water separator 11, energy-saving tank 12, energy-saving pump 13, and extractor 14.

[0019] The finned heater 2 is provided with a fan inlet 21, a second finned heater outlet 22, a heat exchange inlet 23, and a first finned heater outlet 24;

[0020] The fan inlet 21 is connected to the air outlet of the fan 3; the finned heater outlet 22 is connected to the energy-saving inlet of the energy-saving tank 12;

[0021] The outlet 24 of the finned heater is connected to the bottom of DT1, and the outlet of DT1 is connected to the collection tank 4; the top outlet of the collection tank 4 is connected to the lower inlet of the falling film evaporator 6 via a pipeline; the lower outlet of the falling film evaporator 6 is connected to the side port of the flash tank 7; the lower port of the flash tank 7 is connected to the upper inlet of the falling film evaporator 6 via a circulation pump 8; the upper port of the flash tank 7 is connected to the steam jet pump 10; the collection tank 4 is connected to the collection pump 5 in a circulating connection.

[0022] The upper outlet end of the falling film evaporator 6 is connected to the second inlet end of the heat exchanger 9 via a pipeline; the heat exchanger 9 includes a first inlet end, a second inlet end, a first outlet end, and a second outlet end; the second outlet end of the heat exchanger 9 is connected to the heat exchange inlet 23 of the finned heater 2 via a pipeline.

[0023] The steam jet pump 10 is connected to the DT1 energy-saving layer via a pipeline through the steam-water separator 11.

[0024] Furthermore, the energy-saving tank 12 is connected to the leachator 14 via a pipeline through the energy-saving pump 13, and the leachator 14 is connected to the spray head installed inside the energy-saving tank 12 via a pipeline.

[0025] Working principle and process:

[0026] This application proposes a waste heat recovery and reuse system for a vegetable oil mill's evaporator. An additional blower 3 is added, with its outlet connected to a finned heater 2. This blower removes the heat contained in the material within the energy-saving layer of the DT 1. For example, after blowing out hot meal at temperatures above 100°C, the temperature can be reduced by more than 10°C. The generated high-temperature hot air, after being collected and having its meal powder removed by a collection tank 4, enters a falling film evaporator 6. A steam jet pump 10 extracts the steam generated inside the falling film evaporator 6. A flash tank 7 and a circulating pump 8 control the vacuum in the tube side of the falling film evaporator 6 to approximately -50 kPa, allowing the high-temperature hot air to exchange heat with high-temperature condensate injected from the top into the tube side inside the shell side of the falling film evaporator 6. The condensate in the tube side of the falling film evaporator 6 is kept at -50 kPa. Steam is generated at ℃. The steam is then transported by steam jet pump 10 to steam-water separator 11 and then to DT as direct steam. After heat exchange in falling film evaporator 6, the high-temperature hot air enters heat exchanger 9 through exhaust pipe and exchanges heat with mixed oil from mixed oil tank. The residual heat after heat exchange is then exchanged with cold air entering DT energy-saving layer in finned heater 2. The residual heat after heat exchange in finned heater 2 is then passed into energy-saving tank 12 to further collect the residual heat for use in heating the mixed oil circulating in leachator 14. The hot air is discharged, improving the heat recovery efficiency.

[0027] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any simple substitutions or modifications made within the scope of the technical concepts disclosed in this application, and based on the technical solutions of this application, should be within the protection scope of this application.

Claims

1. A waste heat recovery and reuse system for a vegetable oil plant evaporator, characterized in that: Includes DT (1), finned heater (2), fan (3), collection tank (4), collection pump (5), falling film evaporator (6), flash tank (7), circulating pump (8), heat exchanger (9), steam jet pump (10), steam-water separator (11), energy-saving tank (12), energy-saving pump (13), leaching device (14); The finned heater (2) is provided with a fan inlet (21), a second finned heater outlet (22), a heat exchange inlet (23), and a first finned heater outlet (24); The fan inlet (21) is connected to the air outlet of the fan (3); the second outlet (22) of the finned heater is connected to the energy-saving inlet of the energy-saving tank (12); The outlet 1 (24) of the finned heater is connected to the bottom of DT (1), and the outlet of DT (1) is connected to the collection tank (4); the top outlet of the collection tank (4) is connected to the lower inlet of the falling film evaporator (6) via a pipeline; the lower outlet of the falling film evaporator (6) is connected to the side port of the flash tank (7); the lower port of the flash tank (7) is connected to the upper inlet of the falling film evaporator (6) via a circulation pump (8); the upper port of the flash tank (7) is connected to the steam jet pump (10); the lower port of the collection tank (4) is connected to the collection pump (5). The upper outlet end of the falling film evaporator (6) is connected to the heat exchanger (9) via a pipeline; the heat exchanger (9) includes a first inlet end, a second inlet end, a first outlet end, and a second outlet end; the second outlet end of the heat exchanger (9) is connected to the heat exchange inlet (23) of the finned heater (2) via a pipeline; The steam jet pump (10) is connected to the DT (1) energy-saving layer via a pipeline through a steam-water separator (11).

2. The waste heat recovery and reuse system for vegetable oil plant evaporators according to claim 1, characterized in that: The energy-saving tank (12) is connected to the leachator (14) via a pipeline and an energy-saving pump (13). The leachator (14) is connected to a spray head installed inside the energy-saving tank (12) via a pipeline.

Images