Resource utilization system in furfural production process
By separating and reusing the non-condensable gases generated during furfural production, the problems of declining furfural yield and low combustion efficiency have been solved, achieving efficient resource utilization and cost reduction, and improving the economic benefits of enterprises.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2026-03-27
AI Technical Summary
During furfural production, the non-condensable gas at the top of the tower contains organic acids, light components, and moisture. Direct combustion of these components will lead to a decrease in furfural yield, an increase in production costs, and a reduction in combustion efficiency.
Non-condensable gases are initially separated by a gas-slag separator and a condenser. The density difference between furfural and water is used to separate the aqueous phase and the aldehyde phase. The separated aqueous phase is returned to the original liquid distillation tower for redistillation, while the aldehyde phase is refined. The non-condensable gases after refinement are sent to a boiler for combustion. The steam generated by the boiler combustion is used in a wastewater evaporator, thus achieving the rational utilization of resources.
It has increased the yield and purity of furfural, reduced production costs, improved combustion efficiency, achieved efficient resource utilization, and enhanced the economic benefits of enterprises.
Smart Images
Figure CN224040904U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a kind of resource utilization systems, in particular to a kind of resource utilization systems in furfural production process. BACKGROUND
[0002] Furfural (chemical name: furfuraldehyde) is an important bio-based chemical, which is widely used in the fields of synthetic resin, medicine, pesticide, spice and solvent, etc. Its production mainly uses agricultural and forestry wastes (such as corn cob, sugarcane residue, etc.) as raw materials, and hydrolysis mother liquor is obtained after acid hydrolysis. Furfural can be prepared by distillation, deacidification and other steps of hydrolysis mother liquor. In the process of furfural production, furfural is also produced in the process of deacidification and refining, and a lot of non-condensable gas is also produced at the same time. At present, the treatment method for this part of non-condensable gas is to send it directly to the boiler for combustion. However, in the non-condensable gas at the top of the tower, in addition to containing organic acids, light components, moisture and the like, it also contains a certain amount of furfural. If it is directly combusted, it will most directly cause the decrease of furfural yield, further increase the production cost of furfural, also reduce the utilization value of resources, and affect the economic benefit of enterprises. At the same time, due to the presence of moisture in this part, it will affect the calorific value of the combustible gas, and further affect the overall combustion efficiency. SUMMARY
[0003] In order to solve the above problems, the purpose of the utility model is to provide a kind of resource utilization system in furfural production process.
[0004] The utility model is implemented by the following technical solutions:
[0005] A kind of resource utilization system in furfural production process, including hydrolysis kettle, gas residue separator, original liquid condenser, original liquid tank, original liquid distillation tower, sub-aldehyde condenser, sub-aldehyde tank, crude alcohol storage tank, crude alcohol rectification tower, condensing tower and condensate rectification tower;
[0006] The exhaust port of the hydrolysis kettle is communicated with the inlet of the gas residue separator through a pipeline, the gas outlet of the gas residue separator is communicated with the gas inlet of the original liquid condenser, the liquid outlet of the original liquid condenser is communicated with the inlet of the original liquid tank, the liquid outlet of the original liquid tank is communicated with the liquid inlet of the original liquid distillation tower, the top gas outlet of the original liquid distillation tower is communicated with the inlet of the sub-aldehyde condenser, the liquid outlet of the sub-aldehyde condenser is communicated with the inlet of the sub-aldehyde tank, the middle outlet of the sub-aldehyde tank is communicated with the middle inlet of the original liquid distillation tower, the bottom outlet of the sub-aldehyde tank is communicated with the inlet of the crude alcohol storage tank, the outlet of the crude alcohol storage tank is communicated with the liquid inlet of the crude alcohol rectification tower, the tower top gas outlet of the crude alcohol rectification tower is communicated with the inlet of the condensing tower, the liquid outlet of the condensing tower is communicated with the liquid inlet of the condensate rectification tower, and the tower kettle liquid outlet of the condensate rectification tower is communicated with the inlet of the original liquid tank.
[0007] Further, the waste water tank, the waste water evaporator and the concentrated liquid tank are further included, the tower kettle liquid outlet of the raw liquid distillation column is communicated with the inlet of the waste water tank, the outlet of the waste water tank is communicated with the inlet of the waste water evaporator, the evaporation mother liquor outlet of the waste water evaporator is communicated with the inlet of the concentrated liquid tank, the outlet of the concentrated liquid tank and the outlet of the concentrated sulfuric acid storage tank are all communicated with the inlet of the dilute sulfuric acid high tank, the liquid outlet of the dilute sulfuric acid high tank is communicated with the feed inlet of the acid mixing machine, and the discharge outlet of the acid mixing machine is communicated with the feed inlet of the hydrolysis kettle.
[0008] Further, the overhead gas outlet of the condensate rectification column is communicated with the inlet of the light component condenser, the liquid phase outlet of the light component condenser is communicated with the inlet of the light component storage tank, and the outlet of the light component storage tank and the gas phase outlet of the condensation column are all communicated with the fuel inlet of the boiler.
[0009] Further, the primary steam outlet of the boiler is communicated with the shell side inlet of the waste water evaporator, the shell side outlet of the waste water evaporator is communicated with the inlet of the steam condensate water tank, and the steam condensate water tank is communicated with the water inlet of the top drum of the boiler through a condensate water conveying pump.
[0010] The utility model discloses the advantages of:
[0011] By the overhead gas outlet of raw liquid distillation column through the aldehyde condenser condenses, utilize water and furfural density's difference, water phase and aldehyde phase realize primary separation, because water phase still can contain furfural liquid, in order to improve the yield of furfural, therefore, the water phase separated out returns raw liquid distillation column and carries out distillation again, simultaneously, in order to improve the purity of furfural, the aldehyde phase separated out is further rectified, and the liquid after discharging part incondensable gas is rectified again and removes the light component containing in it, and water content and residual aldehyde liquid etc. are returned to the raw liquid tank and participate in distillation again, and the yield of furfural can be improved further, in addition, the liquid after discharging part incondensable gas after rectification and the light component after discharging after rectifying again can be sent into the boiler as fuel and provide the calorific value for boiler combustion, because the water content is very small, and then combustion efficiency can be improved, and the primary steam produced by boiler combustion can be sent into waste water evaporator and be used for evaporating waste water. DRAWINGS:
[0012] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0013] Figure 1 This is a schematic diagram of the system connection in this embodiment.
[0014] In the diagram: 1. Hydrolysis vessel; 2. Gas-slag separator; 3. Raw liquid condenser; 4. Raw liquid tank; 5. Raw liquid distillation tower; 6. Aldehyde separator; 7. Crude aldehyde storage tank; 8. Crude aldehyde distillation tower; 9. Condensation tower; 10. Condensate distillation tower; 11. Wastewater tank; 12. Wastewater evaporator; 13. Concentrate tank; 14. Concentrated sulfuric acid storage tank; 15. Dilute sulfuric acid high-level tank; 16. Acid mixer; 17. Light component condenser; 18. Light component storage tank; 19. Boiler; 20. Steam condensate tank; 21. Condensate transfer pump; 22. Detailed implementation method:
[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0016] Example 1:
[0017] like Figure 1 The system shown is a resource utilization system in the production process of furfural, including a hydrolysis kettle 1, a gas-slag separator 2, a raw liquid condenser 3, a raw liquid tank 4, a raw liquid distillation tower 5, an aldehyde separation condenser 6, an aldehyde separation tank 7, a crude aldehyde storage tank 8, a crude aldehyde rectification tower 9, a condensation tower 10, and a condensate rectification tower 11.
[0018] The exhaust port of the hydrolysis kettle 1 is connected with the inlet of the gas residue separator 2 through a pipeline, the gas outlet of the gas residue separator 2 is connected with the gas inlet of the raw liquid condenser 3, the liquid outlet of the raw liquid condenser 3 is connected with the inlet of the raw liquid tank 4, the liquid outlet of the raw liquid tank 4 is connected with the liquid inlet of the raw liquid distillation column 5, the top gas outlet of the raw liquid distillation column 5 is connected with the inlet of the split aldehyde condenser 6, the liquid outlet of the split aldehyde condenser 6 is connected with the inlet of the split aldehyde tank 7, the middle outlet of the split aldehyde tank 7 is connected with the middle inlet of the raw liquid distillation column 5, the bottom outlet of the split aldehyde tank 7 is connected with the inlet of the crude aldehyde storage tank 8, the outlet of the crude aldehyde storage tank 8 is connected with the liquid inlet of the crude aldehyde rectification column 9, the top gas outlet of the crude aldehyde rectification column 9 is connected with the inlet of the condensation column 10, the liquid outlet of the condensation column 10 is connected with the liquid inlet of the condensation liquid rectification column 11, and the kettle liquid outlet of the condensation liquid rectification column 11 is connected with the inlet of the raw liquid tank 4.
[0019] The embodiment also comprises a waste water tank 12, a waste water evaporator 13 and a concentrated liquid tank 14, the kettle liquid outlet of the raw liquid distillation column 5 is connected with the inlet of the waste water tank 12, the outlet of the waste water tank 12 is connected with the inlet of the waste water evaporator 13, the evaporation mother liquor outlet of the waste water evaporator 13 is connected with the inlet of the concentrated liquid tank 14, the outlet of the concentrated liquid tank 14 and the outlet of the concentrated sulfuric acid storage tank 15 are both connected with the inlet of the dilute sulfuric acid high tank 16, the liquid outlet of the dilute sulfuric acid high tank 16 is connected with the feeding port of the acid mixing machine 17, and the discharging port of the acid mixing machine 17 is connected with the feeding port of the hydrolysis kettle 1.
[0020] The top gas outlet of the condensation liquid rectification column 11 is connected with the inlet of the light component condenser 18, the liquid phase outlet of the light component condenser 18 is connected with the inlet of the light component storage tank 19, and the outlet of the light component storage tank 19 and the gas phase outlet of the condensation column 10 are both connected with the fuel inlet of the boiler 20.
[0021] The primary steam outlet of the boiler 20 is connected with the shell inlet of the waste water evaporator 13, the shell outlet of the waste water evaporator 13 is connected with the inlet of the steam condensate water tank 21, and the steam condensate water tank 21 is connected with the water inlet of the top drum of the boiler 20 through a condensate water conveying pump 22.
[0022] Working explanation:
[0023] When the embodiment is used, the purchased corn cob raw material is loaded into a special transport vehicle by a forklift, sent to the corn cob hopper of the loading and crushing workshop, and then sent to the air-drying hopper elevator by a closed belt conveyor to remove the dirt and sundries in the raw material, and then the raw material is crushed into particles with a particle size of 1-1.5 cm, and then the crushed material is sent to the crushed material storage room by the closed belt conveyor and the material transfer hopper under the crushing machine.
[0024] The evaporation concentrated residue produced in the production process of the concentrated liquid tank 14 is added into the dilute sulfuric acid high tank 16 to prepare a dilute sulfuric acid with a mass fraction of 5%, and the acid mixer 17 is started. The crushed corncob and the 5% dilute sulfuric acid are added into the acid mixer 17 at a mass ratio of 1:0.3-0.4 and stirred uniformly. Then, the pot opening valve of the acid mixer 17 is opened, and the mixed material is loaded into the hydrolysis kettle 1 from the acid mixer 17. During the loading process, a small amount of steam produced by the waste water evaporator 13 is introduced into the hydrolysis kettle 1 to blow off the air remaining in the kettle. After being filled, the kettle opening valve of the hydrolysis kettle 1 is closed.
[0025] After the hydrolysis kettle 1 is filled with the material, steam is introduced into the jacket of the hydrolysis kettle 1 to cook and hydrolyze the material. The material in the hydrolysis kettle 1 is subjected to a hydrolysis reaction. This is a main process for preparing furfural. The poly-pentosan in the raw material is hydrolyzed into pentose by using acid as a hydrolysis agent, and then the pentose is subjected to dehydration and cyclization to generate furfural. When the steam produced by the waste water evaporator 13 is pressurized to 0.15 MPa, the exhaust valve is opened to exhaust air. The exhaust time is about 0.5-1 min. Then, the pressure is continuously increased to the specified pressure of 0.8-1.0 MPa for hydrolysis. The pressure increase should not be too fast, and the pressure increase time is generally 30 min. The hydrolysis reaction starts at this time. The poly-pentosan in the corncob in the kettle is hydrolyzed into pentose in the presence of the catalyst sulfuric acid, and the pentose is further subjected to dehydration and cyclization in the acid solution to produce furfural. Because the hydrolysis temperature is high, the hydrolysis products such as furfural are in a gaseous state, and are mixed with a large amount of water vapor, a small amount of acetic acid and other low-boiling substances and other impurities. This mixed gas is commonly referred to as "aldehyde gas". The aldehyde gas is continuously sent to the aldehyde gas main pipe during the hydrolysis process. The reaction temperature is 170-180 ℃, and the hydrolysis reaction time is 2-3 h. The reaction is basically completed. After the hydrolysis process is completed, the generated aldehyde gas is separated from the slag dust by the gas slag separator 2, and then is introduced into the raw liquid condenser 3 for condensation. The condensed liquid is introduced into the raw liquid tank 4. The raw liquid in the raw liquid tank 4 is introduced into the raw liquid distillation tower 5 at a certain flow rate. During the distillation process, the tower top temperature is controlled at about 97.9 ℃, and the tower kettle temperature should be maintained at about 105 ℃. The furfural aqueous solution with a raw liquid concentration of about 7% is distilled by the raw liquid distillation tower 5. The overhead distilled liquid is azeotropic composition of furfural and water. The waste water discharged from the bottom of the raw liquid distillation tower 5 is temporarily stored in the waste water tank 12, and then is introduced into the waste water evaporator 13. The 1.2 MPa primary saturated steam produced by the boiler 20 is introduced into the shell side of the waste water evaporator 13 to evaporate the waste water. The evaporation concentrated residue (containing 1-2% acetic acid and a small amount of furfural) produced after evaporation is temporarily stored in the concentrated liquid tank 14, and is used for preparing the dilute acid in the hydrolysis process, so as to realize the resource utilization of the process waste water.
[0026] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A resource utilization system in a furfural production process, characterized by, The hydrolysis kettle, the gas residue separator, the raw liquid condenser, the raw liquid tank, the raw liquid distillation column, the partial aldehyde condenser, the partial aldehyde tank, the crude aldehyde storage tank, the crude aldehyde rectification column, the condensation tower and the condensate rectification tower are connected by pipes. The exhaust port of the hydrolysis kettle is connected with the inlet of the gas residue separator by a pipe, the gas outlet of the gas residue separator is connected with the gas inlet of the raw liquid condenser, the liquid outlet of the raw liquid condenser is connected with the inlet of the raw liquid tank, the liquid outlet of the raw liquid tank is connected with the liquid inlet of the raw liquid distillation column, the top gas outlet of the raw liquid distillation column is connected with the inlet of the partial aldehyde condenser, the liquid outlet of the partial aldehyde condenser is connected with the inlet of the partial aldehyde tank, the middle outlet of the partial aldehyde tank is connected with the middle inlet of the raw liquid distillation column, the bottom outlet of the partial aldehyde tank is connected with the inlet of the crude aldehyde storage tank, the outlet of the crude aldehyde storage tank is connected with the liquid inlet of the crude aldehyde rectification column, the top gas outlet of the crude aldehyde rectification column is connected with the inlet of the condensation tower, the liquid outlet of the condensation tower is connected with the liquid inlet of the condensate rectification tower, and the tower kettle liquid outlet of the condensate rectification tower is connected with the inlet of the raw liquid tank.
2. The resource utilization system in a furfural production process according to claim 1, characterized in that, The tower kettle liquid outlet of the raw liquid distillation column is connected with the inlet of the waste water tank, the outlet of the waste water tank is connected with the inlet of the waste water evaporator, the evaporation mother liquor outlet of the waste water evaporator is connected with the inlet of the concentrated liquid tank, the outlet of the concentrated liquid tank and the outlet of the concentrated sulfuric acid storage tank are both connected with the inlet of the dilute sulfuric acid high tank, the liquid outlet of the dilute sulfuric acid high tank is connected with the feed inlet of the acid mixer, and the discharge outlet of the acid mixer is connected with the feed inlet of the hydrolysis kettle.
3. The resource utilization system in a furfural production process according to claim 2, characterized in that, The top gas outlet of the condensate rectification tower is connected with the inlet of the light component condenser, the liquid phase outlet of the light component condenser is connected with the inlet of the light component storage tank, and the outlet of the light component storage tank and the gas phase outlet of the condensation tower are both connected with the fuel inlet of the boiler.
4. The resource utilization system in a furfural production process according to claim 3, characterized in that, The primary steam outlet of the boiler is connected with the shell inlet of the waste water evaporator, the shell outlet of the waste water evaporator is connected with the inlet of the steam condensate tank, and the steam condensate tank is connected with the water inlet of the top drum of the boiler by a condensate delivery pump.