A continuous subcritical or supercritical fluid extraction apparatus

Abstract

The application discloses a continuous subcritical or supercritical fluid extraction device which is composed of an extractor, a feeder and a fluid-solid separator. The extractor is a straight pipe, a spiral pipe or a cylindrical structure, and is a fluid-solid extraction site. The feeder is a spiral feeder or a piston feeder, and its inlet is connected with a substance-to-be-extracted conveying pipe, and its outlet is connected with a lateral inlet of the extractor. The substance-to-be-extracted is continuously sent into the extractor through the feeder. The fluid-solid separator is a rotary drum separator or a cyclone, which is used for separating the extraction fluid containing extractant from the raffinate in the fluid-solid mixture. The inlet of the fluid-solid separator is connected with the outlet of the extractor, the outlet of the extraction fluid containing extractant is connected with an extractant separation system, and the raffinate outlet discharges the raffinate out of the extractor or into the next extractor. The device has the characteristics of high continuity, simple structure, low operation cost, safety and reliability and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical engineering and bioengineering, and particularly relates to a continuous subcritical or supercritical fluid extraction device. TECHNICAL BACKGROUND

[0002] Separation technology plays an important role in modern industry. With the improvement of material living standards, the demand for natural food, medicine, spices and the like is increasing. As a green separation technology, subcritical or supercritical fluid extraction has many advantages over traditional separation technology. However, existing subcritical or supercritical fluid extraction devices mostly use fast-opening sealed intermittent extractors. When using such intermittent extractors for production, the extraction period is long, and when the volume of the extractor is large, there is a phenomenon of uneven extraction. In addition, the end cover of the extractor needs to be frequently opened and closed to complete loading and unloading, and the remaining fluid in the extractor needs to be frequently released and the air in the extractor needs to be frequently removed, which is labor-intensive, low in production efficiency, high in energy consumption, low in safety and reliability, causes great loss of extraction fluid, and seriously restricts the industrialization development of subcritical or supercritical fluid extraction technology.

[0003] The State Intellectual Property Office of China granted a patent with publication number CN108654135B and the name of "a subcritical fluid isobaric extraction and separation system and process flow" on October 16, 2018. The patent is completed by a system composed of a storage buffer unit, a liquefaction unit, a pressurized circulation unit, an extraction unit, a heat exchange unit, a gasification unit, a separation unit, a unloading unit, and a filtration unit. The subcritical fluid in the extraction unit and the same medium supercritical fluid in the separation unit are in an isobaric state, and the heat exchange unit of the subcritical fluid and the same medium supercritical fluid is provided, which reduces the power consumption, cold and heat demand of the system, and saves energy. The invention has the advantages of simple process flow, small equipment investment, and low operating cost, but cannot realize continuous extraction and separation of materials, has safety hazards when repeatedly opening and closing the extractor, and has low extraction efficiency.

[0004] The State Intellectual Property Office of the People's Republic of China granted two invention patents on May 14, 2021, with publication numbers CN110152350B and CN110237561B, respectively, and patent names "A subcritical fluid continuous isobaric extraction separation device system and extraction separation process" and "A supercritical fluid continuous isobaric extraction separation device system and extraction separation process". These two patents are completed by a system composed of a subcritical / supercritical fluid medium source, a pressurizing subsystem, a continuous extraction subsystem, a separation subsystem, and a pressurization circulation subsystem. The extraction separation process implemented by using these two systems forms a quasi-continuous extraction state by periodically and synchronously loading and unloading new materials and extracted material bins into and out of the extractor cylinder, respectively. Although these two invention technologies have high automation and reliable operation, the loading and unloading of the material bin requires a large amount of power, and the sealing requirement between the material bin and the extractor cylinder is high. There are safety hazards when repeatedly pushing and withdrawing the material bin into and out of the extractor cylinder, and the energy loss is large.

[0005] The State Intellectual Property Office of the People's Republic of China granted an invention patent on November 1, 2022, with publication number CN114263780B, and patent name "A high-pressure or superhigh-pressure valve switching system with pressure gradually rising and falling self-balancing". The patent system is composed of a flow supply valve, a flow supply pipe, a backflow valve, a backflow pipe, a pressure balance valve, a pressure balance pipe, an emptying valve, an emptying pipe, and a container. It is applied to the extraction process, and the container is the extractor. The extraction separation process implemented by using this system gradually pressurizes the extractor with new materials to the extraction pressure for extraction, and gradually depressurizes the extractor with extracted materials to the pre-unloading pressure for unloading, and the extractors with gradually rising and falling pressures balance with each other. Although this invention maximizes the use of the pressure of the extractor after extraction before unloading, reduces the pressurization energy consumption, and forms a quasi-continuous extraction state, this technology still does not solve the problem of repeated opening of the extractor, and in order to complete the gradual pressure reduction and pressure rise between extractors, multiple extractors are in a non-extraction state at the same time. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art and provide a continuous subcritical or supercritical fluid extraction device.

[0007] The technical solution adopted by the present application is as follows:

[0008] The continuous subcritical or supercritical fluid extraction device of the present application is composed of an extractor, a feeder, and a fluid-solid separator.

[0009] The extractor is a cylindrical structure, which is a place for fluid-solid extraction; one end and the side of the extractor are respectively provided with an inlet, the side inlet is connected with the outlet of the feeder, and the end inlet is an extraction fluid inlet; the other end of the extractor is provided with an outlet, which is connected with the inlet of the fluid-solid separator; the extraction fluid enters the extractor through the extraction fluid inlet of the extractor, mixes with the powdered or granular extracted material, extracts and transports the powdered or granular raffinate to the outlet of the extractor.

[0010] The feeder is a continuous feeding device for the extracted material, which can be a screw feeder or a piston feeder; the outlet of the feeder is connected with the side inlet of the extractor; and the upper part of the feeder is provided with an extracted material inlet, which is connected with a bin.

[0011] The fluid-solid separator is a place for separating the extraction fluid containing the extracted material from the powdered or granular raffinate in the extracted fluid-solid mixture, which can be a rotary drum separator or a cyclone; the inlet of the fluid-solid separator is connected with the outlet of the extractor; the fluid-solid separator is provided with an extraction fluid outlet and a raffinate outlet; the separated extraction fluid enters the extracted material separator to separate the extracted material and then is recycled; and the separated raffinate is discharged from the extractor or enters the next extractor.

[0012] As a further technical solution, the extracted material inlet Si of the bin is connected with an extracted material conveying pipeline or a conveying belt; and the outlet of the bin is connected with the extracted material inlets of the first feeding cylinder and the second feeding cylinder through two pipelines.

[0013] The pressure balance outlets of the first feeding cylinder and the second feeding cylinder are connected with the balance extraction fluid inlet Fb through a pipeline.

[0014] The extracted material outlets of the first feeding cylinder and the second feeding cylinder are connected with the inlet of the feeder through a pipeline.

[0015] As a further technical solution, a discharge valve is arranged on each of the two pipelines connecting the outlet of the bin with the extracted material inlets of the first feeding cylinder and the second feeding cylinder.

[0016] As a further technical solution, a balance valve is arranged on the pipeline connecting the pressure balance outlets of the first feeding cylinder and the second feeding cylinder with the balance extraction fluid inlet Fb.

[0017] As a further technical solution, a feeding valve is arranged on the pipeline connecting the extracted material outlets of the first feeding cylinder and the second feeding cylinder with the inlet of the feeder.

[0018] As a further technical solution, the first lifting roller and the second lifting roller are respectively fixed to the top of the first feeding cylinder and the second feeding cylinder; and the first lifting roller and the second lifting roller are respectively connected with the first floating hammer and the second floating hammer through flexible ropes.

[0019] As a further technical solution, the first feeding cylinder and the second feeding cylinder are connected with the inlets of the first exhaust valve and the second exhaust valve through pipelines respectively, and the outlets of the first exhaust valve and the second exhaust valve are communicated with the atmosphere.

[0020] As a further technical solution, the extract fluid outlet Fo of the fluid-solid separator is connected with an extract fluid return pipeline, and the raffinate outlet of the fluid-solid separator is connected with a cutting valve, a buffer bin and a discharge valve through pipelines in sequence, and the raffinate outlet So of the discharge valve is connected with a raffinate conveying pipeline or a conveying belt.

[0021] As a further technical solution, a distributor can be arranged at the extract inlet of the extractor, distribution plates can be arranged in the extractor, and a stirrer can be arranged above the distributor or the distribution plates; the extractor can be a straight pipe, a spiral pipe or a snake pipe.

[0022] As a further technical solution, the continuous subcritical or supercritical fluid extraction device can be used in series for more than one stage of extraction, can be used in parallel for more than one stage of extraction, or can be used in series and in parallel at the same time.

[0023] The present application has the following beneficial effects:

[0024] 1. One end and the side of the extractor of the present application are respectively provided with an inlet, the side inlet is connected with the outlet of a feeder, the feeder is a continuous feeding device for the extract, and the upper part of the feeder is provided with an extract inlet and is connected with a bin; the end inlet is an extract fluid inlet, the extract fluid enters the extractor through the extract fluid inlet of the extractor, is mixed with the powdered or granular extract to extract and transport the powdered or granular raffinate to the outlet of the extractor, the other end of the extractor is provided with an extractor outlet, the outlet is connected with the inlet of a fluid-solid separator, the fluid-solid separator is a place for separating the extract fluid and the powdered or granular raffinate in the mixed fluid-solid mixture after extraction, the fluid-solid separator is provided with an extract fluid outlet and a raffinate outlet, the separated extract fluid enters an extract separator to separate the extract and is recycled, and the separated raffinate is discharged from the extractor or enters the next extractor; through the cooperation of the extractor, the feeder and the fluid-solid separator, a continuous subcritical or supercritical fluid extraction device is formed, the continuous fluid-solid extraction and separation effect is achieved, the continuous extraction work can be carried out, the quick opening and quick closing of the general extractor are omitted, the structure is simplified, the safety is ensured, and the energy-saving and environment-friendly effect is achieved.

[0025] 2. The application is designed by the structure between the silo and the feeder, sets two feeding cylinders, through setting floating hammer, lifting roller in the feeding cylinder, then matches emptying valve, feeding valve, discharging valve, balance valve, etc., so that the feeding can realize automatic control; through controlling the input and output of the extracted material and the extraction fluid, realizes continuous subcritical or supercritical fluid extraction and separation, so that compared with general subcritical / supercritical fluid extraction device, the number of control valves is reduced, energy saving, reducing investment and operation cost is achieved.

[0026] 3. When the application is used to constitute continuous subcritical or supercritical fluid extraction device, the number of the application in series or parallel or series-parallel can be flexibly adjusted, which adapts to the process requirement of multi-pressure stage fluid-solid extraction. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is the structural principle schematic diagram of the application;

[0028] Figure 2 It is the structural principle schematic diagram of the application with extracted material feeding device and raffinate discharging device;

[0029] Figure 3 It is the structural principle schematic diagram of the application with distributor, distribution plate and agitator at the extracted material inlet and inside of the extractor;

[0030] Figure 4 It is the structural principle schematic diagram of the application with multi-stage extraction;

[0031] Figure 5 It is the structural principle schematic diagram of the application with extracted material separation and extraction fluid circulation system for continuous subcritical fluid extraction and isobaric supercritical fluid separation;

[0032] Figure 6 It is the structural principle schematic diagram of the application with extracted material separation and extraction fluid circulation system for continuous supercritical fluid extraction and pressure reduction normal gaseous separation.

[0033] REFERENCE SIGNS:

[0034] 1, extractor, 1-1 to 1-n, first extractor to nth extractor, 2, feeder, 2-1 to 2-n, first feeder to nth feeder, 3, fluid-solid separator, 3-1 to 3-n, first fluid-solid separator to nth fluid-solid separator, 4-1, first feeding cylinder, 4-2, second feeding cylinder, 5, hopper, 6-1, first floating weight, 6-2, second floating weight, 7-1, first lifting roller, 7-2, second lifting roller, 8-1, first feeding valve, 8-2, second feeding valve, 9-1, first discharge valve, 9-2, second discharge valve, 10-1, first emptying valve, 10-2, second emptying valve, 11-1, first balancing valve, 11-2, second balancing valve, 12, discharge valve, 13, cutting valve, 14, buffer bin, 15, distributor, 16, agitator, 17, distribution plate, 18, heat pump, 19, circulating pump, 20, heater, 21, extract separation device, 22, cut-off valve, 23, buffer tank, 24, unloading valve, 25, pressure compensating valve, 26, cooler, 27, pressure pump, 28, extract fluid storage tank, 29, pressure reducing valve; Fb, balancing extract fluid inlet, Fi, extract fluid inlet, Fi1 to Fin, first extract fluid inlet to nth extract fluid inlet, Fo, extract fluid outlet, Fo1 to Fon, first extract fluid outlet to nth extract fluid outlet, Si, extract inlet, So, raffinate outlet. DETAILED DESCRIPTION

[0035] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. 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 application belongs.

[0036] The following is a detailed implementation process flow in conjunction with the accompanying drawings.

[0037] Example 1

[0038] In this embodiment, a continuous subcritical or supercritical fluid extraction device with extract inlet and raffinate outlet is disclosed, as shown in Figure 1 , Figure 2 The specific structure includes: extractor 1, feeder 2, fluid-solid separator 3, first feeding cylinder 4-1, second feeding cylinder 4-2, hopper 5, first floating weight 6-1, second floating weight 6-2, first lifting roller 7-1, second lifting roller 7-2, first feeding valve 8-1, second feeding valve 8-2, first discharge valve 9-1, second discharge valve 9-2, first emptying valve 10-1, second emptying valve 10-2, first balancing valve 11-1, second balancing valve 11-2, discharge valve 12, cutting valve 13, buffer bin 14.

[0039] The extract inlet Si of the silo 5 is connected with the extract conveying pipeline or belt, the outlet of the silo 5 is provided with two pipelines, one of which is connected with the inlet of the first discharge valve 9-1, and the other is connected with the inlet of the second discharge valve 9-2, the outlet of the first discharge valve 9-1 is connected with the extract inlet of the first feeding cylinder 4-1 through a pipeline, and the outlet of the second discharge valve 9-2 is connected with the extract inlet of the second feeding cylinder 4-2 through a pipeline.

[0040] The outlet of the first balance valve 11-1 is connected with the pressure balance port of the first feeding cylinder 4-1 through a pipeline, the outlet of the second balance valve 11-2 is connected with the pressure balance port of the second feeding cylinder 4-2 through a pipeline, and the inlets of the first balance valve 11-1 and the second balance valve 11-2 are connected and combined with the balance extraction fluid inlet Fb through pipelines.

[0041] The first lifting roller 7-1 is fixed on the top of the first feeding cylinder 4-1, and the second lifting roller 7-2 is fixed on the top of the second feeding cylinder 4-2, the first lifting roller 7-1 is connected with the first floating hammer 6-1 through a flexible rope, and the second lifting roller 7-2 is connected with the second floating hammer 6-2 through a flexible rope.

[0042] The first feeding cylinder 4-1 is connected with the inlet of the first emptying valve 10-1 through a pipeline, and the outlet of the first emptying valve 10-1 is connected with the atmosphere, the second feeding cylinder 4-2 is connected with the inlet of the second emptying valve 10-2 through a pipeline, and the outlet of the second emptying valve 10-2 is connected with the atmosphere.

[0043] The extract outlet of the first feeding cylinder 4-1 is connected with the inlet of the first feeding valve 8-1 through a pipeline, the extract outlet of the second feeding cylinder 4-2 is connected with the inlet of the second feeding valve 8-2 through a pipeline, and the outlets of the first feeding valve 8-1 and the second feeding valve 8-2 are combined and connected with the inlet of the feeder 2.

[0044] The outlet of the feeder 2 is connected with the extract inlet Si of the extractor 1, the extract fluid inlet Fi of the extractor 1 is connected with the extract fluid conveying pipeline, the outlet of the extractor 1 is connected with the inlet of the fluid-solid separator 3, the extract fluid outlet Fo of the fluid-solid separator 3 is connected with the extract fluid return pipeline, the extract residue outlet of the fluid-solid separator 3 is connected with the cutting valve 13, the buffer bin 14 and the discharge valve 12 in sequence through pipelines, and the extract residue outlet So of the discharge valve 12 is connected with the extract residue conveying pipeline or belt.

[0045] The specific work and operation process are described as follows:

[0046] I. System parameters:

[0047] The highest working pressure P, working time t and working temperature T of the system can be adjusted.

[0048] II. Preparation:

[0049] (1) Close all valves in the equipment, fill the bin 5 with the material to be extracted;

[0050] (2) Raise the first floating weight 6-1 to the top of the first feeding cylinder 4-1; open the first discharge valve 9-1, the material to be extracted enters and fills the first feeding cylinder 4-1, and the first discharge valve 9-1 is closed;

[0051] (3) Open the first balance valve 11-1, fill the first feeding cylinder 4-1 with extraction fluid, close the first balance valve 11-1, open the first evacuation valve 10-1 to evacuate the extraction fluid and air, and then close the first evacuation valve 10-1, repeat at least twice, so that the air in the first feeding cylinder 4-1 is exhausted, and the first evacuation valve 10-1 is closed to be in a standby state;

[0052] (4) Pass the extraction fluid into the extraction fluid inlet Fi of the extractor 1, evacuate the air in the extractor 1, and raise the pressure in the extractor 1 to P;

[0053] (5) Start the feeder 2, and open the cutting valve 13.

[0054] III. Operation:

[0055] (1) The second floating weight 6-2 reaches the bottom of the second feeding cylinder 4-2, the first balance valve 11-1 and the first feeding valve 8-1 are opened, and the second balance valve 11-2 and the second feeding valve 8-2 are closed; the material to be extracted enters the feeder 2; the first floating weight 6-1 is lowered synchronously with the decrease of the material to be extracted in the first feeding cylinder 4-1; the material to be extracted enters the extractor 1 according to the process ratio requirement with the extraction fluid; the material to be extracted and the extraction fluid flow synchronously to the outlet of the extractor 1; the raffinate and the extraction fluid containing extract enter the flow-solid separator 3, the flow-solid separator 3 separates the raffinate and the extraction fluid containing extract; the raffinate enters the buffer bin 14 under the action of gravity through the cutting valve 13; the extraction fluid containing extract enters the subsequent heat exchange, separation, and circulation system after being discharged from the flow-solid separator 3;

[0056] (2) Raise the second floating weight 6-2 to the top of the second feeding cylinder 4-2, open the second discharge valve 9-2, the material to be extracted enters from the bin 5 and fills the second feeding cylinder 4-2, and the second discharge valve 9-2 is closed; open the second balance valve 11-2, fill the second feeding cylinder 4-2 with extraction fluid, close the second balance valve 11-2, open the second evacuation valve 10-2 to evacuate the extraction fluid and air, and then close the second evacuation valve 10-2, repeat at least twice, so that the air in the second feeding cylinder 4-2 is exhausted, and the second evacuation valve 10-2 is closed to be in a standby state;

[0057] (3) The first floating hammer 6-1 reaches the bottom of the first feeding cylinder 4-1, the second balance valve 11-2 and the second feeding valve 8-2 are opened, and the first balance valve 11-1 and the first feeding valve 8-1 are closed; the extractant enters the feeder 2; the second floating hammer 6-2 is lowered synchronously with the decrease of the extractant in the second feeding cylinder 4-2; the extractant enters the extractor 1 according to the process ratio requirement with the extraction fluid; the extractant and the extraction fluid flow synchronously to the outlet of the extractor 1; the raffinate and the extraction fluid containing the extract enter the flow-solid separator 3, the flow-solid separator 3 separates the raffinate and the extraction fluid containing the extract; the raffinate enters the buffer bin 14 under the action of gravity through the cutting valve 13; the extraction fluid containing the extract is discharged from the flow-solid separator 3 and enters the subsequent heat exchange, separation and circulation system;

[0058] (4) The first floating hammer 6-1 is raised to the top of the first feeding cylinder 4-1, the first discharge valve 9-1 is opened, the extractant enters from the bin 5 and fills the first feeding cylinder 4-1, the first discharge valve 9-1 is closed; the first balance valve 11-1 is opened, the extraction fluid is filled into the first feeding cylinder 4-1, the first balance valve 11-1 is closed, the first emptying valve 10-1 is opened and then closed after the extraction fluid and air are discharged, and the process is repeated at least twice, so that the air in the first feeding cylinder 4-1 is discharged, and the first emptying valve 10-1 is closed to be in a standby state;

[0059] The steps (1) to (4) are repeated, the extractant is periodically supplemented to the bin 5 during the circulation process, and the cutting valve 13 is periodically closed and the discharge valve 12 is periodically opened to unload the raffinate in the buffer bin 14, after the buffer bin 14 is unloaded, the discharge valve 12 is closed and the cutting valve 13 is opened.

[0060] Example two:

[0061] In this embodiment, a continuous subcritical or supercritical fluid extraction device is disclosed, which is provided with a distributor, a distribution plate and a stirrer at the extractant inlet and inside the extractor, as shown in Figure 3 The specific structure is: an extractor 1, a feeder 2, a flow-solid separator 3, a distributor 15, a stirrer 16, a distribution plate 17, an extraction fluid inlet Fi, an extraction fluid outlet Fo, an extractant inlet Si, and a raffinate outlet So; the outlet of the feeder 2 is connected to the extractant inlet of the extractor 1, the distributor 15 is arranged at the extractant inlet of the extractor 1, the stirrer 16 is arranged above the distributor 15, the distribution plate 17 is uniformly arranged in the extractor 1, the outlet of the extractor 1 is connected to the inlet of the flow-solid separator 3, the extraction fluid outlet Fo of the flow-solid separator 3 is connected to the extraction fluid return pipeline, and the raffinate outlet So of the flow-solid separator 3 is connected to the solid outlet pipeline.

[0062] I. System parameters:

[0063] The highest working pressure P, the working time t and the working temperature T of the system can be adjusted.

[0064] II. Preparation:

[0065] The extractor 1 is filled with extraction fluid through the extraction fluid inlet Fi, the air in the extractor is exhausted and the pressure in the extractor 1 is increased to P; the extracted substance is fed into the feeder 2 through the extracted substance inlet Si of the feeder 2.

[0066] III. Operation:

[0067] The feeder 2 continuously feeds the extracted substance into the extractor 1, the extracted substance in the extractor 1 is mixed with the extraction fluid under the action of the distributor 15 and the distribution plate 17, the mixed flow of the extracted substance and the extraction fluid is further mixed and uniformly distributed by the agitator 16, forming a uniformly distributed flow of the mixed flow of the extracted substance and the extraction fluid, the extraction fluid extracts the extracted substance while flowing, and finally moves upward together to the extractor outlet, then enters the flow-solid separator 3, in which the raffinate and the extraction fluid containing the extract are separated from each other, the extraction fluid containing the extract leaves the extractor 2 through the extraction fluid outlet Fo and enters the subsequent equipment to complete the separation of the extract and the extraction fluid, and the raffinate is discharged through the raffinate outlet So or enters the next extractor.

[0068] Example III:

[0069] In this embodiment, a multi-stage continuous subcritical or supercritical fluid extraction device with extracted substance feeding device and raffinate discharging device is disclosed, such as Figure 4The specific structure is shown as follows: first extractor 1-1 to nth extractor 1-n, first feeder 2-1 to nth feeder 2-n, first liquid-solid separator 3-1 to nth liquid-solid separator 3-n, first feeding cylinder 4-1, second feeding cylinder 4-2, stock bin 5, first floating hammer 6-1, second floating hammer 6-2, first lifting roller 7-1, second lifting roller 7-2, first feeding valve 8-1, second feeding valve 8-2, first discharge valve 9-1, second discharge valve 9-2, first emptying valve 10-1, second emptying valve 10-2, first balance valve 11-1, second balance valve 11-2, discharge valve 12, cutting valve 13, buffer bin 14; the extract inlet Si of the stock bin 5 is connected with an extract conveying pipeline or a conveying belt, the outlet of the stock bin 5 is connected with the inlets of the first discharge valve 9-1 and the second discharge valve 9-2 through a pipeline, the outlets of the first discharge valve 9-1 and the second discharge valve 9-2 are respectively connected with the extract inlets of the first feeding cylinder 4-1 and the second feeding cylinder 4-2 through a pipeline, the outlets of the first balance valve 11-1 and the second balance valve 11-2 are respectively connected with the pressure balance ports of the first feeding cylinder 4-1 and the second feeding cylinder 4-2 through a pipeline, the inlets of the first balance valve 11-1 and the second balance valve 11-2 are connected with the balance extraction fluid inlet through a pipeline, the first lifting roller 7-1 and the second lifting roller 7-2 are respectively fixed on the top of the first feeding cylinder 4-1 and the second feeding cylinder 4-2 and are respectively connected with the first floating hammer 6-1 and the second floating hammer 6-2 through a flexible rope, the first feeding cylinder 4-1 and the second feeding cylinder 4-2 are respectively connected with the inlets of the first emptying valve 10-1 and the second emptying valve 10-2 through a pipeline, the outlets of the first emptying valve 10-1 and the second emptying valve 10-2 are connected with the atmosphere, the outlets of the first feeding cylinder 4-1 and the second feeding cylinder 4-2 are respectively connected with the inlets of the first feeding valve 8-1 and the second feeding valve 8-2 through a pipeline, the outlets of the first feeding valve 8-1 and the second feeding valve 8-2 are connected with the inlet of the first feeder 2-1, the outlet of the first feeder 2-1 is connected with the side inlet of the first extractor 1-1, the extraction fluid inlet Fi1 of the first extractor 1-1 is connected with an extraction fluid conveying pipeline, the outlet of the first extractor 1-1 is connected with the inlet of the first liquid-solid separator 3-1, the extraction fluid outlet Fo1 of the first liquid-solid separator 3-1 is connected with an extraction fluid return pipeline, and the raffinate outlet of the first liquid-solid separator 3-1 is connected with the inlet of the second feeder 2-2 through a pipeline.The outlet of the second feeder 2-2 is connected to the side inlet of the second extractor 1-2, the extraction fluid inlet Fi2 of the second extractor 1-2 is connected to the extraction fluid conveying pipeline, the outlet of the second extractor 1-2 is connected to the inlet of the second liquid-solid separator 3-2, the extraction fluid outlet Fo2 of the second liquid-solid separator 3-2 is connected to the extraction fluid return pipeline, …, until the outlet of the nth feeder 2-n is connected to the side inlet of the nth extractor 1-n, the extraction fluid inlet Fin of the nth extractor 1-n is connected to the extraction fluid conveying pipeline, the outlet of the nth extractor 1-n is connected to the inlet of the nth liquid-solid separator 3-n, the extraction fluid outlet Fon of the nth liquid-solid separator 3-n is connected to the extraction fluid return pipeline, the raffinate outlet of the nth liquid-solid separator 3-n is connected to the cutting valve 13, the buffer bin 14 and the discharge valve 12 in sequence through pipelines, and the extract outlet So of the discharge valve 12 is connected to the raffinate conveying pipeline or conveying belt.

[0070] I. System parameters:

[0071] The maximum working pressure P, working time t and working temperature T of the system can be adjusted.

[0072] II. Preparation:

[0073] The steps (1)-(3) in the preparation of the embodiment are the same as the steps (1)-(3) in the preparation of the embodiment I.

[0074] (4) The extraction fluid is introduced into the first extraction fluid inlet Fi1 to the nth extraction fluid inlet Fin of the first extractor 1-1 to the nth extractor 1-n, the air in the first extractor 1-1 to the nth extractor 1-n is discharged, and the pressure in the first extractor 1-1 to the nth extractor 1-n is increased to P.

[0075] (5) The first feeder 2-1 to the nth feeder 2-n is started, and the cutting valve 13 is opened.

[0076] III. Working:

[0077] In the embodiment I, the "extractor 1" is replaced by "first extractor 1-1", the "feeder 2" is replaced by "first feeder 2-1", the "liquid-solid separator 3" is replaced by "first liquid-solid separator 3-1", and the "raffinate enters the buffer bin 14 under the action of gravity through the cutting valve 13" in the steps (1) and (3) of the embodiment I is replaced by "raffinate enters the second feeder 2-2 inlet under the action of gravity through the pipeline", and the "extraction fluid containing extractives is discharged from the liquid-solid separator 3 and then enters the subsequent heat exchange, separation and circulation system" is replaced by "extraction fluid containing extractives is discharged from the first liquid-solid separator 3-1 and then enters the subsequent heat exchange, separation and circulation system"; the working steps of the first extractor 1-1 are the same as the working steps (1)-(4) of the embodiment I.

[0078] Repeat steps (1) to (4) in this way, and replenish the extracted material to the silo 5 periodically during the cycle;

[0079] (5) The raffinate separated from the first solid-liquid separator 3-1 is fed into the second extractor 1-2 via the second feeder 2-2. The extraction fluid enters the second extractor 1-2 through the extraction fluid inlet Fi2 to complete the extraction. The mixture of extractant, raffinate, and extraction fluid in the second extractor 1-2 enters the second solid-liquid separator 3-2. The separated extraction fluid containing extractant enters the extraction fluid return pipeline through the extraction fluid outlet Fo2 of the second solid-liquid separator 3-2, ... until the raffinate separated from the nth solid-liquid separator 3-n is fed into the nth extractor via the nth feeder 2-n. Extraction fluid enters the nth extractor 1-n through the extraction fluid inlet Fin and completes extraction. The mixture of extractant, raffinate, and extraction fluid enters the nth fluid-solid separator 3-n. The separated extraction fluid containing extractant enters the extraction fluid return pipeline from the extraction fluid outlet Fon and enters the subsequent heat exchange, separation, and circulation system. The separated raffinate exits from the outlet of the nth fluid-solid separator 3-n through pipelines and is connected in sequence through the cutting valve 13, the buffer chamber 14, and the discharge valve 12. The raffinate outlet So of the discharge valve 12 is connected to the raffinate conveying pipeline or conveyor belt.

[0080] (6) Periodically close the cutting valve 13 and open the discharge valve 12 to discharge the residue in the buffer chamber 14. After emptying the buffer chamber 14, close the discharge valve 12 and open the cutting valve 13.

[0081] Example 4:

[0082] This embodiment discloses a continuous subcritical fluid extraction isobaric supercritical fluid separation device with an extractant separation and extraction fluid circulation system, such as... Figure 5The specific structure is shown as follows: including an extractor 1, a feeder 2, a liquid-solid separator 3, a heat pump 18, a circulating pump 19, a heater 20, an extractant separator 21, a cut-off valve 22, a buffer tank 23, a discharge valve 24, a pressure compensation valve 25, a pressurizing pump 26, a condenser 27, an extractant fluid storage tank 28; the extractant inlet Si of the feeder 2 is connected with an extractant supply pipe, the outlet of the feeder 2 is connected with a side inlet of the extractor 1, the outlet of the extractor 1 is connected with an inlet of the liquid-solid separator 3, the extractant outlet So of the liquid-solid separator 3 is connected with an extractant outlet pipe, the extractant fluid outlet of the liquid-solid separator 3 is connected with a cold side inlet of the heat pump 18 through a pipe, the cold side outlet of the heat pump 18 is connected with an inlet of the heater 20, the outlet of the heater 20 is connected with an inlet of the extractant separator 21, the extractant outlet of the extractant separator 21 is connected with an inlet of the cut-off valve 22, the outlet of the cut-off valve 22 is connected with an inlet of the buffer tank 23, the outlet of the buffer tank 23 is connected with an inlet of the discharge valve 24, the outlet of the discharge valve 24 is connected with the atmosphere, the extractant fluid outlet of the extractant separator 21 is connected with a hot side inlet of the heat pump 18, the hot side outlet of the heat pump 18 is connected with an inlet of the circulating pump 19, the outlet of the extractant fluid storage tank 28 is connected with an inlet of the condenser 27, the outlet of the condenser 27 is connected with an inlet of the pressurizing pump 26, the outlet of the pressurizing pump 26 is connected with an inlet of the pressure compensation valve 25, the outlet of the pressure compensation valve 25 is connected with the outlet of the circulating pump 19 and the inlet of the extractor 1 through a pipe to realize a three-way connection.

[0083] I. System parameters:

[0084] The highest working pressure P, working time t and working temperature T of the system can be adjusted.

[0085] II. Preparation:

[0086] The extractant fluid is introduced into the extractor 1 through the extractant fluid inlet, the air in the extractor 1 is exhausted and the pressure in the extractor 1 is increased to P; the extractant is sent into the feeder 2 through the extractant inlet Si.

[0087] III. Working:

[0088] (1) The feeder 2 continuously sends the extractant into the extractor 1, the extractant is uniformly mixed with the extractant fluid entering through the extractant fluid inlet, and flows to the outlet of the extractor 1, and the extraction of the extractant is completed in the flowing process;

[0089] (2) The extractant, the extractant, the extractant fluid entering the liquid-solid separator 3, the extractant and the extractant fluid containing the extractant are separated in the liquid-solid separator 3, the extractant leaves the continuous subcritical fluid extraction isobaric separation equipment through the extractant outlet So, the extractant fluid containing the extractant enters the cold side inlet of the heat pump 18 of the extractant separation and extractant fluid circulation system through the extractant fluid outlet;

[0090] (3) The extractant extraction fluid is heated by the heat pump 18, flows out from the cold side outlet of the heat pump 18, enters the heater 20, is heated to the required temperature for separation, and enters the extractant separator 21 to complete the separation of the extractant and the extraction fluid;

[0091] (4) The separated extraction fluid enters the hot side inlet of the heat pump 18, is cooled by the heat pump 18 to the required temperature value at the inlet of the circulating pump 19, flows out from the hot side outlet of the heat pump 18, and enters the inlet of the circulating pump 19;

[0092] (5) The extraction fluid is pressurized by the circulating pump 19 and reenters the extractor 1;

[0093] (6) The disconnecting valve 22 is opened, the extractant enters the buffer tank 23, and when the buffer tank 23 is full, the disconnecting valve 22 is closed and the discharge valve 24 is opened to discharge the extractant, and the discharge valve 24 is closed.

[0094] The cycle is repeated.

[0095] After the extractant and the extractant are discharged, the continuous subcritical fluid extraction isobaric separation equipment system loses pressure, and the extraction fluid in the extraction fluid storage tank 28 is supplemented to the continuous subcritical fluid extraction isobaric separation equipment system through the condenser 27 and the pressurizing pump 26 to maintain the system pressure.

[0096] Example Five:

[0097] In this embodiment, a continuous supercritical fluid extraction pressure reduction constant gaseous separation equipment with an extractant separation and extraction fluid circulation system is disclosed, as shown in Figure 6 The specific structure includes an extractor 1, a feeder 2, a fluid-solid separator 3, a heat pump 18, a circulating pump 19, a heater 20, an extractant separator 21, a disconnecting valve 22, a buffer tank 23, a discharge valve 24, a pressure supplementing valve 25, a pressurizing pump 26, a condenser 27, an extraction fluid storage tank 28, and a pressure reducing valve 29. In this embodiment, the extraction fluid outlet of the fluid-solid separator 3 is connected to the inlet of the pressure reducing valve 29, and the outlet of the pressure reducing valve 29 is connected to the cold side inlet of the heat pump 18, and the connection mode of the other structures is the same as that of the structures in Example Four.

[0098] I. System Parameters:

[0099] The maximum working pressure P, the working time t, and the working temperature T of the system can be adjusted.

[0100] II. Preparation:

[0101] The extraction fluid is introduced into the extractor 1 through the extraction fluid inlet, the air in the extractor 1 is exhausted, and the pressure in the extractor 1 is raised to P; and the extracted material is sent into the feeder 2 through the extracted material inlet Si.

[0102] The cycle is repeated.

[0103] III. Operation:

[0104] This example is the same as the operation steps of Example 4, except that the step (2) of Example 4, "the extract-containing extraction fluid passes through the extraction fluid outlet into the heat pump 18 cold side inlet of the extract separation and extraction fluid circulation system" is replaced by "the extract-containing extraction fluid passes through the extraction fluid outlet into the pressure reducing valve 29 of the extract separation and extraction fluid circulation system to reduce the pressure to the separation pressure, and enters the heat pump 18 cold side inlet".

[0105] The present application overcomes the shortcomings of the prior art step-by-step pressure increasing container and step-by-step pressure reducing container, which are independent of each other, have a large number of invalid containers, and require large equipment investment, thereby making the system unnecessarily complex. The present application realizes continuous production of solid extract or separation, has the advantages of simple structure, green energy saving, high automation, reliable operation, excellent process, etc.

Claims

1. A continuous subcritical or supercritical fluid extraction device, characterized in that, It consists of an extractor, a feeder, and a fluid-solid separator. The extractor is a cylindrical structure and is the site for fluid-solid extraction. One end and one side of the extractor have inlets, with the side inlet connected to the outlet of the feeder. The feeder is a continuous feeding device for the extractable material, with an extractable inlet at the top connected to a hopper. The end inlet is the extractant fluid inlet, which enters the extractor and mixes with the powdered or granular extractable material, then transports the powdered or granular raffinate to the extractor outlet. The other end of the extractor is the extractor outlet, which is connected to the inlet of the fluid-solid separator. The fluid-solid separator is used to separate the extractant fluid containing the extractant from the powdered or granular raffinate in the extracted fluid-solid mixture. The fluid-solid separator has an extractant fluid outlet and a raffinate outlet. The separated extractant fluid enters the raffinate separator to separate the extractant and is then recycled. The separated raffinate is discharged from the extractor or enters the next extractor. The outlet of the silo is connected to the extract inlet of the first feed cylinder and the second feed cylinder respectively through two pipes; The pressure balance ports of the first and second feed cylinders are connected to the equilibrium extraction fluid inlet Fb via a pipeline. The extractant outlets of the first and second feed cylinders are connected to the feeder inlet via a combined pipeline. The first lifting roller and the second lifting roller are respectively fixed to the top of the first feeding cylinder and the second feeding cylinder. The first lifting roller and the second lifting roller are respectively connected to the first floating hammer and the second floating hammer through flexible ropes.

2. The continuous subcritical or supercritical fluid extraction equipment as described in claim 1, characterized in that, The material inlet Si of the silo is connected to the material conveying pipeline or conveyor belt.

3. The continuous subcritical or supercritical fluid extraction equipment as described in claim 2, characterized in that, A discharge valve is installed on each of the two pipes that connect the outlet of the silo to the extraction inlet of the first and second feed cylinders.

4. The continuous subcritical or supercritical fluid extraction equipment as described in claim 2, characterized in that, A balancing valve is installed on the pipe connecting the pressure balancing port of the first feed cylinder, the pressure balancing port of the second feed cylinder, and the balancing fluid inlet Fb.

5. The continuous subcritical or supercritical fluid extraction equipment as described in claim 2, characterized in that, Feeding valves are installed on the pipes connecting the extractant outlet of the first feeding cylinder and the extractant outlet of the second feeding cylinder to the feeder inlet.

6. The continuous subcritical or supercritical fluid extraction equipment as described in claim 2, characterized in that, The first and second feeding cylinders are connected to the inlets of the first and second vent valves respectively via pipes, and the outlets of both the first and second vent valves are open to the atmosphere.

7. The continuous subcritical or supercritical fluid extraction equipment as described in claim 1, characterized in that, The extractant outlet Fo of the fluid-solid separator is connected to the extractant return pipeline. The raffinate outlet of the fluid-solid separator is connected in sequence to the cutting valve, buffer bin, and discharge valve through pipelines. The raffinate outlet So of the discharge valve is connected to the raffinate conveying pipeline or conveyor belt.

8. The continuous subcritical or supercritical fluid extraction equipment as described in claim 1, characterized in that, A distributor is installed at the inlet of the extractant, and distribution plates are arranged inside the extractant. A stirrer is installed above the distributor or distribution plates. The extractor is a straight tube, a spiral coil, or a snake tube.

9. A continuous subcritical or supercritical fluid extraction device as described in claim 1, characterized in that, The continuous subcritical or supercritical fluid extraction equipment can be used in series to achieve two or more stages of extraction, or in parallel to achieve extraction by multiple extractors in the same stage, or in both series and parallel.

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