Solvent evaporator gas phase heat recovery system
By converting the gas phase heat of the solvent evaporator into low-pressure steam through heat pump technology, the problem of wasted thermal energy and cooling water in the solvent evaporator is solved, and energy savings are achieved in the oil processing process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- MYANDE GRP CO LTD
- Filing Date
- 2025-06-09
- Publication Date
- 2026-06-09
AI Technical Summary
In existing technologies, the gas phase heat released by solvent evaporators is not utilized, resulting in a waste of thermal energy and cooling water, and increasing equipment investment and power consumption in oil processing.
Heat pump technology is used to convert the gas phase heat of the solvent evaporator into low-pressure steam, which is used to supply steam directly to the vapor layer of the desiccant, thereby reducing the consumption of steam and cooling water.
By recovering the vapor phase heat of the solvent evaporator through a heat pump system, the steam and cooling water consumption in the oil processing process is reduced, thus saving production costs.
Smart Images
Figure CN224340100U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a heat recovery system, and more particularly to a solvent evaporator gas phase heat recovery system, belonging to the field of waste heat utilization technology. Background Technology
[0002] Oil extraction typically uses hexane as a solvent, dissolving vegetable oil in it to form a mixed oil. The concentration of the mixed oil is controlled at 20-35% (w / w). This mixed oil then enters an evaporation system to evaporate and recover the solvent from the vegetable oil. The evaporation system mainly includes a first evaporator, a second evaporator, and a stripping tower. Over 90% of the solvent is evaporated in the first and second evaporators. The evaporated solvent then enters the evaporator-condenser through a vacuum vapor transfer tube, which uses cooling water as the cold source.
[0003] The above traditional technical solutions have the following problems: 1. The gas phase heat released by the solvent evaporator is not utilized, resulting in a large amount of heat energy wastage;
[0004] 2. Because the heat released by solvent condensation is very large, the demand for cooling water is very large, resulting in a lot of energy waste; and large-scale circulating water pumps and cooling towers are required, which greatly increases the equipment investment and power consumption of oil processing.
[0005] 3. Water needs to be continuously added to the cooling tower, which increases water consumption during the grease processing process. Utility Model Content
[0006] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, and such simplifications or omissions should not be construed as limiting the scope of the present invention.
[0007] In view of the problems existing in the above and / or prior art, this utility model is proposed.
[0008] The purpose of this invention is to overcome the problems existing in the prior art and provide a solvent evaporator vapor phase heat recovery system. The system uses heat pump technology to convert the vapor phase heat of the solvent evaporator into low-pressure steam. The low-pressure steam is used to supply steam to the direct vapor layer of the desiccant, thereby reducing steam consumption and cooling water consumption in the oil processing process.
[0009] To solve the above technical problems, this utility model provides a solvent evaporator vapor phase heat recovery system, including a desolventizer. The top solvent vapor outlet of the desolventizer is connected to the shell-side inlet of a first evaporator, the outlet of the mixed oil inlet pipe is connected to the bottom inlet of the tube side of the first evaporator, the tube-side outlet of the first evaporator is connected to a first evaporator tank, the bottom outlet of the first evaporator tank is connected to the shell-side inlet of a mixed oil heat exchanger, the shell-side outlet of the mixed oil heat exchanger is connected to the bottom inlet of the tube side of a second evaporator, and the tube-side outlet of the second evaporator is connected to a second evaporator tank; the first evaporator... The top secondary steam outlets of the evaporator tank and the second evaporator tank are connected to the shell-side inlet of the heat pump evaporator. The tube-side outlet of the heat pump evaporator is connected to the inlet of the compressor. The outlet of the compressor is connected to the shell-side inlet of the heat pump condenser through a high-pressure pipeline. The shell-side outlet of the heat pump condenser is connected to the tube-side inlet of the heat pump evaporator through an expansion valve and a low-pressure pipeline. The tube-side outlet of the heat pump condenser is connected to the middle inlet of the flash tank. The bottom outlet of the flash tank is connected to the tube-side inlet of the heat pump condenser through a circulating pump. The top secondary steam outlet of the flash tank is connected to the steam heating jacket inlet of the desiccant.
[0010] As an improvement of this utility model, the bottom outlet of the second evaporator tank is connected to the upper inlet of the stripping tower via a secondary steam extraction pump, the bottom outlet of the stripping tower is connected to the tube-side inlet of the mixed oil heat exchanger via a stripping extraction pump, and the tube-side outlet of the mixed oil heat exchanger is connected to the crude oil outlet pipe via the hot side of the crude oil cooler.
[0011] As a further improvement of this utility model, the shell-side outlet of the heat pump evaporator is connected to a vacuum tube.
[0012] As a further improvement of this utility model, the water inlet on the side wall of the flash tank is connected to a water supply pipe.
[0013] As a further improvement of this utility model, the shell-side outlet of the first evaporator is connected to a solvent condensate collection pipe, and the outlet of the solvent condensate collection pipe is connected to a water distribution tank.
[0014] Compared with the prior art, the present invention has achieved the following beneficial effects: 1. The present invention uses the gas phase heat of the solvent evaporator as the heat source of the heat pump evaporator. The working fluid in the heat pump system is vaporized. After being compressed by the compressor, the vaporized working fluid enters the heat pump condenser. The heat released by the heat pump condenser heats the hot water to generate low-pressure steam. The low-pressure steam serves as the heat source of the descaling machine, reducing the steam consumption in the oil processing process.
[0015] 2. Using a heat pump working fluid to condense the solvent vapor phase in the evaporator reduces cooling water consumption and lowers the power consumption of the workshop's circulating water pumps and cooling towers.
[0016] 3. By adopting the technical solution of this utility model, 50 kg of steam and 0.8 kWh of electricity can be saved per ton of soybeans (due to reduced load on circulating water pumps and cooling towers). Heat pumps, however, increase electricity consumption by 10 kWh per ton of soybeans. Based on a steam price of 250 yuan / ton and an electricity price of 0.7 yuan / kWh, a soybean crushing workshop with a daily output of 6000 tons can save 36,400 yuan in production costs daily. Assuming 320 operating days per year, this translates to annual savings of 11.65 million yuan. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments 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. The drawings are provided for reference and illustration only and are not intended to limit this utility model. Wherein:
[0018] Figure 1 This is a flowchart of the solvent evaporator vapor phase heat recovery system of this utility model;
[0019] In the diagram: DT. Evaporator; C1. Compressor; V1. Expansion valve; T1. Flash tank; S1. Stripping tower;
[0020] E1. First evaporator; E2. Mixed oil heat exchanger; E3. Second evaporator; E4. Crude oil cooler; E5. Heat pump evaporator; E6. Heat pump condenser;
[0021] P1. Secondary steam extraction pump; P2. Stripping extraction pump; P3. Circulation pump;
[0022] G1. Mixed oil inlet pipe; G2. Crude oil outlet pipe; G3. Water replenishment pipe; G4. Vacuum extraction pipe; G5. Solvent condensate collection pipe. Detailed Implementation
[0023] In the following description of this utility model, the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device must have a specific orientation.
[0024] To make the technical means, creative features, achieved objectives and effects of this utility model easier to understand, the present utility model will be further described below with reference to specific illustrations. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.
[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
[0026] like Figure 1 As shown, the solvent evaporator vapor phase heat recovery system of this utility model includes a desiccant DT, a compressor C1, an expansion valve V1, a flash tank T1, and a stripping tower S1. The top solvent vapor outlet of the desiccant DT is connected to the shell-side inlet of the first evaporator E1. The shell-side outlet of the first evaporator E1 is connected to a solvent condensate collection pipe G5. The outlet of the solvent condensate collection pipe G5 is connected to a water separator. The separated solvent returns to the leachate for re-extraction.
[0027] The outlet of the mixed oil inlet pipe G1 is connected to the bottom inlet of the tube side of the first evaporator E1. The tube side outlet of the first evaporator E1 is connected to the first evaporator tank. The bottom outlet of the first evaporator tank is connected to the shell side inlet of the mixed oil heat exchanger E2. The shell side outlet of the mixed oil heat exchanger E2 is connected to the bottom inlet of the tube side of the second evaporator E3. The tube side outlet of the second evaporator E3 is connected to the second evaporator tank. The bottom outlet of the second evaporator tank is connected to the inlet of the secondary evaporator extraction pump P1. The outlet of the secondary evaporator extraction pump P1 is connected to the upper inlet of the stripping tower S1. The bottom outlet of the stripping tower S1 is connected to the inlet of the stripping extraction pump P2. The outlet of the stripping extraction pump P2 is connected to the tube side inlet of the mixed oil heat exchanger E2. The tube side outlet of the mixed oil heat exchanger E2 is connected to the hot side inlet of the crude oil cooler E4. The hot side outlet of the crude oil cooler E4 is connected to the crude oil outlet pipe G2.
[0028] The secondary steam outlets at the top of both the first and second evaporator tanks are connected to the shell-side inlet of heat pump evaporator E5. The shell-side outlet of heat pump evaporator E5 is connected to vacuum pipe G4. The tube-side outlet of heat pump evaporator E5 is connected to the inlet of compressor C1. The outlet of compressor C1 is connected to the shell-side inlet of heat pump condenser E6 via a high-pressure pipe. The shell-side outlet of heat pump condenser E6 is connected to the inlet of expansion valve V1. The outlet of expansion valve V1 is connected to the tube-side inlet of heat pump evaporator E5 via a low-pressure pipe.
[0029] The bottom outlet of flash tank T1 is connected to the inlet of circulating pump P3, the outlet of circulating pump P3 is connected to the tube-side inlet of heat pump condenser E6, the tube-side outlet of heat pump condenser E6 is connected to the middle inlet of flash tank T1, the water inlet on the side wall of flash tank T1 is connected to water inlet pipe G3, and the top secondary steam outlet of flash tank T1 is connected to the steam heating jacket inlet of desiccant DT.
[0030] The mixed oil from the extractor, with a concentration of 25-35%, enters the tube side of the first evaporator E1 through the mixed oil inlet pipe G1. It is heated by the 72°C vapor phase from the descaling unit in the shell side. At the top of the first evaporator E1, gas-liquid separation occurs, with the separated vapor phase reaching approximately 60°C. This vapor phase then enters the shell side of the heat pump evaporator E5. The mixed oil separated from the first evaporator E1, also at approximately 60°C, enters the shell side of the mixed oil heat exchanger E2, where it is heated to 75°C before entering the tube side of the second evaporator E3. There, it is heated by the vapor in the shell side for evaporation. The vapor phase exiting the top of the second evaporator E3 reaches 110°C and merges with the vapor phase from the first evaporator E1 before entering the shell side of the heat pump evaporator E5.
[0031] After the non-condensable gases are condensed in the shell side of the heat pump evaporator E5, they are extracted by the vacuum pipe G4. The mixed oil at the outlet of the second evaporator E3 has a temperature of about 110°C and is pumped into the stripping tower S1 by the secondary evaporator extraction pump P1. The outlet temperature of the stripping tower is 105°C, and the residual solute is below 50ppm. It is then pumped into the tube side of the mixed oil heat exchanger E2 and the tube side of the crude oil cooler E4 by the stripping extraction pump P2 and cooled to 50°C. Finally, it is sent to the tank area through the crude oil outlet pipe G2.
[0032] The heat pump working fluid is heated and vaporized in the tube side of the heat pump evaporator E5. The working fluid gas is then compressed by the compressor C1 and enters the shell side of the heat pump condenser E6. The condensate from the heat pump condenser is depressurized by the expansion valve V1 and then re-enters the tube side of the heat pump evaporator E5, thus completing the cycle. Soft water is supplied to the flash tank T1 through the water supply pipe G3, and then transported to the tube side of the heat pump condenser E6 through the circulation pump P3. The water is heated and vaporized here, and then enters the flash tank T1 where gas-liquid separation occurs. The separated water vapor has a pressure of 0.5 bar and a temperature of 111°C, and enters the direct vapor layer of the desiccant DT.
[0033] The above description is merely a preferred embodiment of the present utility model, showing and describing the basic principles, main features, and advantages of the present utility model. It is not intended to limit the scope of patent protection of the present utility model. Those skilled in the art should understand that the present utility model is not limited to the above embodiments. In addition to the above embodiments, the present utility model may have other implementations without departing from the spirit and scope of the present utility model. Various changes and improvements to the present utility model are also possible. All technical solutions formed by equivalent substitutions or equivalent transformations fall within the scope of protection claimed by the present utility model. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents. Technical features not described in the present utility model can be implemented by or using existing technology, and will not be elaborated here.
Claims
1. A solvent evaporator vapor phase heat recovery system, comprising a descaling unit (DT), characterized in that: The top solvent vapor outlet of the desolventizer (DT) is connected to the shell-side inlet of the first evaporator (E1), the outlet of the mixed oil inlet pipe (G1) is connected to the bottom inlet of the tube side of the first evaporator (E1), the tube-side outlet of the first evaporator (E1) is connected to the first evaporator tank, the bottom outlet of the first evaporator tank is connected to the shell-side inlet of the mixed oil heat exchanger (E2), the shell-side outlet of the mixed oil heat exchanger (E2) is connected to the bottom inlet of the tube side of the second evaporator (E3), and the tube-side outlet of the second evaporator (E3) is connected to the second evaporator tank. The top secondary steam outlets of the first evaporator tank and the second evaporator tank are both connected to the shell-side inlet of the heat pump evaporator (E5). The tube-side outlet of the heat pump evaporator (E5) is connected to the inlet of the compressor (C1). The outlet of the compressor (C1) is connected to the shell-side inlet of the heat pump condenser (E6) through a high-pressure pipeline. The shell-side outlet of the heat pump condenser (E6) is connected to the tube-side inlet of the heat pump evaporator (E5) through an expansion valve (V1) and a low-pressure pipeline. The tube-side outlet of the heat pump condenser (E6) is connected to the middle inlet of the flash tank (T1). The bottom outlet of the flash tank (T1) is connected to the tube-side inlet of the heat pump condenser (E6) via the circulating pump (P3). The top secondary steam outlet of the flash tank (T1) is connected to the steam heating jacket inlet of the desiccant (DT).
2. The solvent evaporator vapor phase heat recovery system according to claim 1, characterized in that: The bottom outlet of the second evaporator tank is connected to the upper inlet of the stripping tower (S1) via a secondary steam extraction pump (P1). The bottom outlet of the stripping tower (S1) is connected to the tube-side inlet of the mixed oil heat exchanger (E2) via a stripping extraction pump (P2). The tube-side outlet of the mixed oil heat exchanger (E2) is connected to the crude oil outlet pipe (G2) via the hot side of the crude oil cooler (E4).
3. The solvent evaporator vapor phase heat recovery system according to claim 1, characterized in that: The shell-side outlet of the heat pump evaporator (E5) is connected to the vacuum tube (G4).
4. The solvent evaporator vapor phase heat recovery system according to claim 1, characterized in that: The water inlet on the side wall of the flash tank (T1) is connected to the water supply pipe (G3).
5. The solvent evaporator vapor phase heat recovery system according to any one of claims 1 to 4, characterized in that: The shell-side outlet of the first evaporator (E1) is connected to a solvent condensate collection pipe, and the outlet of the solvent condensate collection pipe is connected to a water distribution tank.