Biodiesel by-product crude glycerine desalting device
The secondary centrifugal desalination process of the crude glycerol desalination unit, a byproduct of biodiesel, solved the problem of sodium sulfate clogging, improved production efficiency, and reduced energy consumption and costs.
Patent Information
- Application Number
- CN202520306196.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2026-03-06
- Estimated Expiration
- 2035-02-25
AI Technical Summary
In existing technologies, excessive sodium sulfate precipitates in the evaporation and distillation towers as a byproduct of biodiesel, leading to tube blockage, reduced production efficiency, and increased production costs.
A two-stage centrifugal desalination process is adopted, including a horizontal centrifuge at room temperature and a horizontal centrifuge at high temperature, combined with a heat exchanger and a spiral plate cooler. The process involves a first centrifugation at room temperature and a second centrifugation at high temperature to remove sodium sulfate and reduce the risk of blockage in the evaporation and distillation towers.
It effectively removes sodium sulfate, reduces clogging in evaporation and distillation towers, improves production efficiency, and reduces energy consumption and production costs.
Smart Images
Figure CN223970141U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of glycerol production equipment for organic chemical products, and in particular to an equipment for producing glycerol using crude glycerol, a byproduct of biodiesel, specifically a desalting device for crude glycerol, a byproduct of biodiesel. Technical Background
[0002] Crude glycerol, a byproduct of biodiesel production, contains approximately 65% glycerol. After water is evaporated in an evaporator, glycerol is obtained by distillation in a distillation tower. Because crude glycerol contains a high level of oil and impurities in addition to the main component glycerol, it requires purification before entering the evaporator. Currently, the common purification process for removing oil and impurities from crude glycerol involves acidifying it with concentrated sulfuric acid to a pH of 1.5-2.0, followed by precipitation at 80-85℃ for 24 hours. This process removes most of the oil and impurities. The clear, central portion of the crude glycerol is then removed and alkalized by adding liquid alkali to adjust the pH to 11.5-11.8, thus completing the oil and impurity removal purification process. Because the purification of crude glycerol, a byproduct of biodiesel, will produce a large amount of salt, mainly sodium sulfate, and since evaporation towers and distillation towers are generally tubular, the excess sodium sulfate in crude glycerol can easily clog the tubes of the evaporation tower and distillation tower during the evaporation and dehydration process, which will have an adverse effect on production efficiency and production cost. Utility Model Content
[0003] The purpose of this invention is to provide a biodiesel byproduct crude glycerol desalting device that is simple and compact in structure, convenient and efficient in operation, and can effectively remove sodium sulfate precipitated from crude glycerol. This solves the problem in the prior art that excessive sodium sulfate precipitated from crude glycerol can easily clog the tubes after entering the evaporator and distillation tower, thereby reducing production efficiency and increasing production costs.
[0004] To achieve the above objectives, the present invention provides a desalting device for crude glycerol, a byproduct of biodiesel production, comprising an acidification and heat preservation sedimentation tank 1, an alkalization stirring tank 5, a room-temperature horizontal centrifuge 8, a No. 1 sodium sulfate receiving tank 9, a room-temperature material pump 10, a heat exchanger 11, a spiral plate cooler 12, a wastewater tank 13, a high-temperature material pump 14, an evaporation tower 15, a high-temperature horizontal centrifuge 16, and a No. 2 sodium sulfate receiving tank 17. The acidification and heat preservation sedimentation tank 1 is equipped with a digital display thermometer 2 at its top and a bottom outlet pipe 3 for discharging impurities and oil at its bottom. The lower middle part of the acidification and heat preservation sedimentation tank 1 is connected to the upper part of the alkalization stirring tank 5 via a pipe. The alkalization stirring tank 5 is equipped with a liquid alkali feed port 4 at its top, an outlet pipe with an alkalization stirring tank side valve 7 at its lower middle part, and a feed port of the room-temperature horizontal centrifuge 8 via a pipe with an alkalization stirring tank bottom valve 6 at its bottom. The discharge port of the centrifuge 8 is connected to the No. 1 sodium sulfate receiving tank 9; the liquid discharge port of the ambient temperature horizontal centrifuge 8 is connected to the outlet pipe of the side valve 7 of the alkalization stirring tank and then connected to the inlet of the ambient temperature material pump 10; the outlet of the ambient temperature material pump 10 is connected to the feed port at the bottom of the heat exchanger 11; the top discharge pipe of the heat exchanger 11 is connected to the upper part of the evaporation tower 15 after being connected to the high temperature material pump 14; the top steam outlet pipe of the evaporation tower 15 is connected to the steam inlet at the upper part of the heat exchanger 11, and the steam outlet pipe at the lower part of the heat exchanger 11 is connected to the wastewater tank 13 after being connected to the spiral plate cooler 12; the bottom discharge pipe of the evaporation tower 15 is connected to the feed port of the high temperature horizontal centrifuge 16, the bottom discharge port of the high temperature horizontal centrifuge 16 is connected to the No. 2 sodium sulfate receiving tank 17, and the liquid discharge pipe 18 of the high temperature horizontal centrifuge 16 is connected to the distillation tower.
[0005] This utility model's desalting device for crude glycerol, a byproduct of biodiesel, employs a two-stage centrifugal desalination process and has the following technical features and benefits:
[0006] 1. The first desalination is carried out by a horizontal centrifuge at room temperature 8. The crude glycerol after acid addition, heat preservation and precipitation and purification by alkali is centrifuged to remove the precipitated sodium sulfate accumulated at the bottom of the acidified heat preservation precipitation tank 1, which can greatly reduce the blockage of the tubes of the evaporation tower 15.
[0007] 2. After evaporation and dehydration in evaporation tower 15, the sodium sulfate in crude glycerol is in a saturated state, and a large amount of sodium sulfate will precipitate out. The sodium sulfate is denser than glycerol. After centrifugation again in high-temperature horizontal centrifuge 16, most of the sodium sulfate can be removed, which greatly reduces the risk of blockage in the subsequent distillation tower tubes. This solves the problem in the existing technology that excessive sodium sulfate precipitation in crude glycerol can easily block the tubes after entering the evaporation tower and distillation tower, thereby reducing production efficiency and increasing production costs.
[0008] 3. By using heat exchanger 11 and spiral plate cooler 12, the water vapor at the top of the evaporation tower exchanges heat with the crude glycerin material, preheating the crude glycerin while condensing the water vapor, thus reducing energy consumption and production costs.
[0009] 4. Simple structure, convenient and efficient operation. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of the structure of the biodiesel by-product crude glycerol desalting device of this utility model.
[0011] Attached labels: 1. Acidification and heat preservation sedimentation tank; 2. Digital display thermometer; 3. Tank bottom outlet pipe; 4. Liquid alkali feed port; 5. Alkaliification stirring tank; 6. Alkaliification stirring tank bottom valve; 7. Alkaliification stirring tank side valve; 8. Ambient temperature horizontal centrifuge; 9. No. 1 sodium sulfate receiving tank; 10. Ambient temperature material pump; 11. Heat exchanger; 12. Spiral plate cooler; 13. Wastewater tank; 14. High temperature material pump; 15. Evaporation tower; 16. High temperature horizontal centrifuge; 17. No. 2 sodium sulfate receiving tank; 18. Liquid material outlet pipe. Detailed Implementation
[0012] The following description, in conjunction with the accompanying drawings and specific embodiments, provides a more detailed explanation of the biodiesel byproduct crude glycerol desalting device of this invention.
[0013] Figure 1As shown, the desalting device for crude glycerol, a byproduct of biodiesel, includes an acidification and heat preservation sedimentation tank 1, an alkalization stirring tank 5, a room-temperature horizontal centrifuge 8, a No. 1 sodium sulfate receiving tank 9, a room-temperature material pump 10, a heat exchanger 11, a spiral plate cooler 12, a wastewater tank 13, a high-temperature material pump 14, an evaporation tower 15, a high-temperature horizontal centrifuge 16, and a No. 2 sodium sulfate receiving tank 17. The top of the acidification and heat preservation sedimentation tank 1 is equipped with a digital display thermometer 2, which controls the temperature at 80-85℃. The bottom is equipped with a bottom outlet pipe 3 for discharging impurities and oil. Impurities at the bottom of the acidification and heat preservation sedimentation tank 1 and the upper layer of oil are discharged from the bottom outlet pipe 3. The lower part of the acidification and heat preservation sedimentation tank 1 is connected to the alkalization stirring tank 5 via a pipe. The upper part is connected; the top of the alkalization stirring tank 5 is provided with a liquid alkali feed port 4, the middle and lower part is provided with an outlet pipe with an alkalization stirring tank side valve 7, and the bottom is connected to the feed port of the ambient temperature horizontal centrifuge 8 through a pipe with an alkalization stirring tank bottom valve 6. The bottom discharge port of the ambient temperature horizontal centrifuge 8 is connected to the No. 1 sodium sulfate receiving tank 9. After acidification, heat preservation, precipitation, oil removal, and impurity removal, the clear crude glycerol in the middle of the acidification, heat preservation, and precipitation tank 1 enters the alkalization stirring tank 5. Liquid alkali is added through the liquid alkali feed port 4 to adjust the pH to 11.5-11.8; the liquid discharge port of the ambient temperature horizontal centrifuge 8 merges with the outlet pipe with the alkalization stirring tank side valve 7 and is connected to the inlet of the ambient temperature material pump 10; the outlet of the ambient temperature material pump 10 is connected to the bottom of the heat exchanger 11. The feed inlet of the alkalized crude glycerol is connected to the heat exchanger 11. After centrifugation by a horizontal centrifuge 8 at room temperature, the lower layer of sodium sulfate is discharged to the sodium sulfate receiving tank 9 (No. 1). The upper layer of crude glycerol is transported to the heat exchanger 11 by a material pump 10. The top discharge pipe of the heat exchanger 11 is connected to the upper part of the evaporation tower 15 after being connected to a high-temperature material pump 14. The top steam outlet pipe of the evaporation tower 15 is connected to the steam inlet located in the upper part of the heat exchanger 11. The steam outlet pipe located in the lower part of the heat exchanger 11 is connected to the wastewater tank 13 after being connected to the spiral plate cooler 12. The crude glycerol preheated in the heat exchanger 11 is transported to the evaporation tower 15 by the high-temperature material pump 14 for evaporation and dehydration. Water vapor enters from the top of the evaporation tower 15. Heat exchanger 11 performs heat exchange. The condensed liquid and uncondensed steam then enter the spiral plate cooler 12 from the lower part of heat exchanger 11 for further cooling. The completely cooled cooling water is collected in wastewater tank 13. The bottom discharge pipe of the evaporation tower 15 is connected to the feed port of the high-temperature horizontal centrifuge 16. The bottom discharge port of the high-temperature horizontal centrifuge 16 is connected to the No. 2 sodium sulfate receiving tank 17. The liquid outlet pipe 18 of the high-temperature horizontal centrifuge 16 is connected to the distillation tower. After dehydration, the sodium sulfate in the crude glycerol is saturated and precipitated. Most of the sodium sulfate is discharged to the No. 2 sodium sulfate receiving tank 17 through the high-temperature horizontal centrifuge 16. The crude glycerol from the liquid outlet pipe 18 enters the next process, the distillation tower, for distillation and purification to obtain glycerol product.
[0014] This invention employs a two-stage centrifugal desalination process. After alkalization, a first stage of room-temperature centrifugal desalination is performed, followed by a second stage of high-temperature centrifugal desalination after evaporation and dehydration. This effectively removes sodium sulfate, reducing the burden on the evaporation and distillation towers, minimizing pipe blockage, and solving the problem of easy clogging in the tubes of existing evaporation and distillation towers, thus improving production efficiency. Simultaneously, the water vapor generated during dehydration in the evaporation tower is utilized to exchange heat with the crude glycerol before it enters the tower in a heat exchanger. This process both cools the evaporated water vapor and heats the crude glycerol, effectively reducing energy consumption and production costs. It also solves the problem in existing technologies where excessive sodium sulfate precipitation in crude glycerol easily clogs the tubes of the evaporation and distillation towers, leading to reduced production efficiency and increased production costs.
Claims
1. A biodiesel by-product crude glycerol desalination device, comprising an acidification heat preservation precipitation tank (1), an alkalization stirring tank (5), a normal temperature material pump (10), a heat exchanger (11), a spiral plate cooler (12), a wastewater tank (13), a high temperature material pump (14) and an evaporation tower (15); the top of the acidification heat preservation precipitation tank (1) is provided with a digital thermometer (2), the bottom is provided with a tank bottom outlet pipeline (3) for discharging impurities and oil, and the middle and lower part of the acidification heat preservation precipitation tank (1) is connected with the upper part of the alkalization stirring tank (5) through a pipeline; the top of the alkalization stirring tank (5) is provided with a liquid alkali feeding port (4), and the middle and lower part is provided with an outlet pipeline with an alkalization stirring tank side valve (7); the outlet of the normal temperature material pump (10) is connected with a feeding port arranged at the bottom of the heat exchanger (11); the top discharge pipeline of the heat exchanger (11) is connected with the upper part of the evaporation tower (15) after connecting the high temperature material pump (14); the steam outlet pipeline of the evaporation tower (15) is connected with a steam inlet arranged in the middle and upper part of the heat exchanger (11), and the steam outlet pipeline arranged in the middle and lower part of the heat exchanger (11) is connected with the wastewater tank (13) after connecting the spiral plate cooler (12); characterized in that: It also includes normal temperature horizontal centrifuge (8), No. 1 sodium sulfate salt receiving tank (9), high temperature horizontal centrifuge (16) and No. 2 sodium sulfate salt receiving tank (17); the bottom of the alkali mixing tank (5) is connected with the feed inlet of the normal temperature horizontal centrifuge (8) through a pipeline with an alkali mixing tank bottom valve (6), the bottom discharge outlet of the normal temperature horizontal centrifuge (8) is connected with No. 1 sodium sulfate salt receiving tank (9); the liquid discharge outlet of the normal temperature horizontal centrifuge (8) is connected with the outlet pipeline of the alkali mixing tank side valve (7) and then connected with the inlet of the normal temperature material pump (10); the bottom discharge pipeline of the evaporation tower (15) is connected with the feed inlet of the high temperature horizontal centrifuge (16), the bottom discharge outlet of the high temperature horizontal centrifuge (16) is connected with No. 2 sodium sulfate salt receiving tank (17), and the liquid material outlet pipeline (18) of the high temperature horizontal centrifuge (16) is connected with the distillation tower.