CN207877625U - The system for continuously preparing furfural using lignocellulose raw material - Google Patents

Abstract

The utility model is related to a kind of system continuously preparing furfural using lignocellulose raw material, which includes acid solution output unit, raw material mixed cell, feed unit, main body reaction member, discharging unit, stripping reaction tower, separative element and purification unit.The utility model is continuous process system truly, realizes continuously acquiring for product in time, reduces labor intensity, improves production efficiency.Entire technological design is reasonable, and furaldehyde yield is high, and specific energy consumption is low.

Description

The system for continuously preparing furfural using lignocellulose raw material

Technical field

The utility model belongs to furfural production technical field, especially relates to the technology that two-step method continuously prepares furfural.

Background technology

Furfural (also known as furtural) is a kind of important chemical products, is widely used in synthetic plastic, medicine, pesticide etc. The demand of industrial circle, annual whole world furfural is very big.Furfural can selectively extract from oil, vegetable oil therein Unsaturated component can also extract aromatised fraction therein from lubricating oil and diesel oil.With the aggravation and environmental protection of energy crisis It is required that producing the furfural of high added value using reproducible agriculture and forestry organic waste material, more and more paid attention to by people.

At present at industrial scale, the method that can uniquely obtain furfural is still to pass through hydrolysis using corncob as raw material Method obtains.According to pentosan hydralysis in corncob hemicellulose and pentose monomers cyclodehydration whether in the same reactor It carries out, furfural production technology can be divided into one-step method and two-step method again.

One-step method is that the raw material containing hemicellulose is fitted into hydrolyzer, under acid catalysis and certain temperature, makes hemicellulose Element is hydrolyzed into pentose, while pentose is dehydrated to form furfural again.One-step method is easy to operate because its equipment investment is few, in furfural work Industry is widely used.But one-step method is uneven since raw material heats, and furaldehyde yield is low, large steam consumption, and environmental pollution is serious.

Two-step method is that the dehydration of the hydrolysis of hemicellulose and pentose is divided into two steps, respectively in different equipment Middle completion, reaction equation are as follows：

At present at home or in the world, the first step in two-step method --- utilize the work of lignocellulose raw material sugaring Skill --- the method for generally use dilute acid hydrolysis, existing acid hydrolysis device are batch reactors, and labor intensity is big, produces Efficiency is low, takes up a large area, is seriously polluted.In addition, due to acid solution existing for present reactor be only attached to surface of material, material and The problems such as mixing of acid solution is uneven, vapor heating is uneven, cause to hydrolyze sugar decomposition is serious, by-product is more, sugar yield is small, Sugared concentration is low.

Second step in two-step method --- dehydration of pentoses cyclization process, due to the decomposition reaction of furfural itself and and anti- Answer the polycondensation reaction of intermediate so that furaldehyde yield is relatively low.It is right since the developed countries such as America and Europe stop furfural production already The research report of furfural technology is seldom.

Therefore, research and utilization lignocellulose raw material continuously prepares the system of furfural for solving in the prior art Stating technical problem has positive meaning.

Utility model content

The utility model is proposed in view of above-mentioned the problems of the prior art.The utility model provides a kind of utilization The system that lignocellulose raw material continuously prepares furfural, solve at least in the prior art can not successive reaction, furfural receive The problems such as rate is low, and byproduct of reaction is more, and labor intensity is big, and production cost is high, low production efficiency, environmental pollution is serious, Neng Gouyou It raises labour productivity to effect, reduces labor intensity, improve furaldehyde yield, avoid side reaction as far as possible, specific energy consumption is low, Environmental pollution is small, rationally utilizes energy.

According to the utility model, a kind of system continuously preparing furfural using lignocellulose raw material is provided, this is System includes：Acid solution output unit, for exporting the first acid solution and the second acid solution respectively；Raw material mixed cell exports single with acid solution Member is connected, for mixing raw material with the first acid solution to form mixture and continuous conveying mixture；Feed unit, it is mixed with raw material It closes unit to be connected, for receiving mixture, compressing mixture and conveying mixture outward；Main body reaction member, with into Material unit is connected with acid solution output unit, for receiving mixture and the second acid solution respectively, and is filled under the pressure higher than normal pressure Divide stirring and blend mixture and the second acid solution so that it is reacted；Discharging unit is connected with main body reaction member, for reaction Obtained product is separated by solid-liquid separation, and exports the pentose solution containing acid；Strip reaction tower comprising be located at the steam at top Outlet and the first feed(raw material)inlet, and stripped vapor entrance and the acid solution outlet positioned at bottom, wherein the first feed(raw material)inlet is used for The pentose solution containing acid of first temperature of the reception from discharging unit is as raw material to carry out cyclodehydration reaction, stripped vapor Entrance is used to receive the stripped vapor of second temperature, and steam (vapor) outlet is for providing by the steam containing furfural obtained by the reaction, acid solution Outlet from bottom of tower for producing acid solution；Separative element is connected with steam (vapor) outlet, for neutralizing the acid in steam containing furfural, and The salt of gained is detached with steam containing furfural, to provide the steam containing furfural of acid content reduction；And purification unit, it is used for pure Change the furfural of gained.

The utility model is continuous process system truly, realizes continuously acquiring for product in time, drop Low labor intensity improves production efficiency, and the hydrolysis of lignocellulose raw material is only sent out in main body reaction member It is raw, reduce the generation of by-product, sugar obtained by the reaction can be discharged in time, improve sugared yield and sugared concentration.In pentose system During standby furfural, it is catalyst to strip and liquid mineral acid can be used in reaction tower, and catalytic capability is strong, and reaction temperature is low；Vapour Low concentration liquid glucose can also be handled by carrying reaction tower, without being concentrated to liquid glucose, simplify production technology.The utility model uses The technological process of steam counter-flow stripping reaction, reaction process is added without any extractant, the pentose solution containing acid from top to bottom with Steam contacts, and while cyclodehydration reaction generation furfural occurs, the furfural of generation is taken out of by steam, and this avoid furfurals Side reaction occurs in liquid acidic environment for a long time.The utility model stripping reaction tower bottom of tower can not set reboiler, vapour Condensation reflux unit can not be set by putting forward reaction column overhead；Due to usually containing salt and other carbohydrate impurity in the solution containing pentose, Heat exchange is easy to prevent the coking of reboiler surface and prevent reaction from being carried out continuously in reboiler under acidic environment, straight using steam Stripping heating is connect to avoid this problem and save equipment investment.Meanwhile direct steam stripping heating can also be by adjusting steaming Vapour amount controls the residence time of liquid, avoids overreact.The utility model simplifies furfural production process, subsequent furfural point From and simple purification it is easy, entire technological design is reasonable, and compared with traditional one-step technology, the high 10-30% of furaldehyde yield is single Position low energy consumption 10-20%.

In a preferred embodiment, raw material mixed cell may include ribbon mixer, be used for raw material and First acid solution is uniformly mixed under auger effect and forms mixture, and provides continuous feed to feed unit.Using spiral shell Rotation mixer can make raw material and acid solution mix more uniform, it is ensured that sequential hydrolysis reaction is smoothed out.

In a preferred embodiment, feed unit may include the feeding screw with compression function, for pair Mixture compress and mixture is transported to main body reaction member.Hydrolysis in main body reaction member is higher than normal pressure Under conditions of carry out, the feeding screw of feed unit can ensure that the material in main body reaction member counter will not leap up back into material list Member, and pressure stability in main body reaction member is maintained, the hydrolysis in guarantee main body reaction member is under a steady pressure It carries out；In addition, by using feeding screw, moreover it is possible to which offer is continuously and stably fed, and is not in clogging.

In a preferred embodiment, feed unit can also include being fed respectively with raw material mixed cell and spiral First taper tremie pipe of device connection, for receiving the mixture from raw material mixed cell, and is conveyed to feeding screw. Feed unit is received using the first taper tremie pipe and conveys mixture, it can be ensured that mixture smoothly enters spiral charging Device, to can avoid because from raw material mixed cell export uniformly mixed mixture mobility it is poor caused by block or It conveys unsmooth.

In a preferred embodiment, main body reaction member may include helical reactors, which is Flat-pushing streaming and without compression function.Hydrolysis, spiral reverse occur in the helical reactors of main body reaction member for mixture When device being answered to be set as laminar flow, can to complete the reaction and improve reaction efficiency so that the mixture in reactor is arbitrary Stage of reaction solid-liquid mixing ratio is consistent, improves the efficiency of hydrolysis.

In a preferred embodiment, main body reaction member can also include being connect with feed unit, for receiving Second taper tremie pipe of mixture is additionally provided with the acid solution being connect with acid solution output unit at the top of the second taper tremie pipe Adding set, for adding the second acid solution.It is received using the second taper tremie pipe in main body reaction member and conveys mixture It can ensure that mixture smoothly enters helical reactors, avoid the solidliquid mixture mobility exported from feed unit is poor from leading The blocking or conveying of cause are unsmooth；It is further supplemented needed for reaction in the acid solution adding set that the top of the second taper tremie pipe is arranged Acid solution to reach the solid-to-liquid ratio of setting so that hydrolysis can be carried out efficiently.

In a preferred embodiment, acid solution adding set can add the second acid solution by spray.Using spray Mode can the second acid solution be more uniformly sprayed to the mixture from feed unit, additionally aid the second acid solution and mixing The uniform mixing of object.

In a preferred embodiment, main body reaction member can also include vapor inlet port, be used to receive height Warm steam.Steam input is able to maintain that the reaction temperature of main body reaction member in suitable range, avoids temperature from declining and draw The reaction rate risen reduces.

In a preferred embodiment, main body reaction member can also include blow valve, to be discharged in reaction process The fixed gas of generation.In such manner, it is possible to ensure pressure in main body reaction member in suitable range, so that hydrolysis Stablize and carries out.

In a preferred embodiment, the temperature and pressure of main body reaction member can be for example, by the temperature of adjustment charging Degree and pressure control the modes such as blow valve to be adjusted and be arranged.It is 100- that main body reaction member, which can be configured to temperature, 200 DEG C, pressure 0.1-1.8MPa；Preferably, temperature is 100-160 DEG C, pressure 0.1-0.8MPa；It is highly preferred that temperature It is 115-125 DEG C, pressure 0.15-0.25MPa；Most preferably, temperature is 120 DEG C, pressure 0.2MPa.

In a preferred embodiment, discharging unit may include the spiral discharging device with compression function, and spiral goes out Glassware is used to carry out squeezing filtering and separation of solid and liquid to product.The spiral discharging device of discharging unit can ensure to export product During material spray will not occur, be able to maintain that pressure stability in main body reaction member；It is additionally capable of providing continuously and stably Discharging, is not in clogging.

In a preferred embodiment, the temperature of the first acid solution is preferably 40-95 DEG C, more preferably 55-65 DEG C, most Preferably 60 DEG C；The temperature of second acid solution is preferably 110-200 DEG C, more preferably 125-135 DEG C, most preferably 130 DEG C.It is any Within the scope of capable of realizing the acid concentration of lignocellulosic hydrolysis the utility model the considerations of, in a preferred embodiment In, the acid concentration of the first acid solution and/or the second acid solution can be 0.1wt%-10wt%.

In a preferred embodiment, the temperature and pressure in raw material mixed cell and in feed unit can pass through Such as the modes such as temperature and pressure for adjusting charging are adjusted and are arranged.Raw material mixed cell can be arranged to temperature 40-90 DEG C, pressure is normal pressure；It is 40-90 DEG C that feed unit, which can be arranged to temperature,.

In a preferred embodiment, the first acid solution and/or the second acid solution can be the acid from acid solution outlet extraction Liquid.Acid cycle utilization can reduce the processing cost of acid solution, and can reduce environmental pollution.

In a preferred embodiment, feeding screw may include compression section, compression section internal diameter and screw pitch along into Material direction tapers into.

In a preferred embodiment, feeding screw can also include material plug section, material plug section be located at compression section it Afterwards and internal diameter and screw pitch remain unchanged.

In a preferred embodiment, spiral discharging device may include compression section, and compression section internal diameter and screw pitch edge go out Material direction tapers into.

In a preferred embodiment, spiral discharging device can also include material plug section, material plug section be located at compression section it Afterwards and internal diameter and screw pitch remain unchanged.

In a preferred embodiment, sieve can be equipped at spiral discharging device wall, spiral discharging device passes through sieve Net discharge liquid；Spiral discharging device end can be equipped with solids discharge mouth, for solid to be discharged.

In a preferred embodiment, separative element can also include filter device, which is used for containing The steam containing furfural that acid amount reduces is filtered, to provide filtered steam containing furfural.Using for filter device can be further It removes the impurity in steam containing furfural and effectively reduces the yield of the aldehyde mud in follow-up Furfural Treating Process, extend primary distillation tower again Boil the service life of device and heat exchange unit.

In a preferred embodiment, which can also include heat exchange unit, the heat exchange unit Including：Material channel, including the second feed(raw material)inlet, the second feed(raw material)inlet are used to receive penta containing acid of the temperature less than the first temperature Sugar juice and material outlet, material outlet are connected with the first feed(raw material)inlet, for providing the first temperature to stripping reaction tower Pentose solution containing acid；And furfural channel, it is mutually isolated with material channel but heat exchange can be carried out, and include that furfural enters Mouthful, furfural entrance is connected with separative element, is used to receive steam containing furfural and furfural outlet, furfural from separative element and goes out Mouth is connected with purification unit, for providing furfuryl aldehyde solution.The heat of the steam containing furfural can be effectively utilized using heat exchange unit Come improve containing acid pentose solution temperature, can faster reach reaction temperature, avoid the waste of energy.

In a preferred embodiment, purification unit may include：Primary distillation tower has the primary distillation tower positioned at middle part Feed inlet, the primary distillation tower steam (vapor) outlet positioned at top and aqueous phase liquid entrance boil steam inlet and primary distillation tower again positioned at bottom Bottom liquid exports；Furfuryl aldehyde solution heat exchanger, furfuryl aldehyde solution through furfuryl aldehyde solution heat exchanger be cooled to third temperature through primary distillation tower into Material mouth enters primary distillation tower；It is furnished with condensation reflux unit equipped with fore-running tower reboiler, tower top in primary distillation tower bottom of tower；Condensation reflux unit packet Include primary distillation tower condenser and primary distillation tower liquid separation tank；Fore-running tower reboiler becomes after being used to exchange heat a part of bottom liquid boils steaming again Vapour returns to primary distillation tower through boiling steam inlet again；Primary distillation tower condenser is connected with primary distillation tower steam (vapor) outlet, and being used for will after purification Steam containing furfural condense to the condensate liquid of the 4th temperature；Primary distillation tower liquid separation tank, is connected with primary distillation tower condenser, for receiving Condensate liquid carries out liquid separation to obtain aqueous phase liquid and oil phase liquid, and sends aqueous phase liquid back to primary distillation tower through aqueous phase liquid entrance, It regard oil phase liquid output as chaff aldehyde product.

In a preferred embodiment, separative element may include lye input port to input lye, for neutralizing Acid in steam containing furfural avoids acid from making furfural decomposition or polycondensation in subsequent processing.

In a preferred embodiment, separative element may include cyclone separator, for steaming salt with containing furfural Vapour detaches, to provide the steam containing furfural of acid content reduction.Cyclone separator has simple in structure, easy to operate, high temperature resistant, longevity Order the advantages that long.

In a preferred embodiment, this prepare furfural system can also include acid solution heat exchanger, for receive from The acid solution of acid solution outlet outflow simultaneously carries out thermal energy recycling.

In a preferred embodiment, purification unit can also include refining plant, for chaff aldehyde product into Row is dehydrated and takes off light refined to obtain product furfural.

In a preferred embodiment, purification unit further includes waste water evaporator, waste water evaporator and primary distillation tower tower Bottom liquid outlet is connected, for being evaporated recycling to another part bottom liquid exported from primary distillation tower bottom liquid.

In a preferred embodiment, the first temperature can be set to 80-155 DEG C, and second temperature can be 150-220 DEG C, stripping reaction column overhead temperatures can be set to 140-210 DEG C, and column bottom temperature can be set to 150-220 ℃.Stripping reaction tower tower top pressure can be set to 0.26-2.2MPa, and tower bottom pressure can be set to 0.37-2.2MPa. Stripping the temperature and pressure of reaction tower can be adjusted and be arranged by adjusting temperature and pressure of charging etc..

In a preferred embodiment, third temperature can be set to 20-100 DEG C, and the 4th temperature can be set It is set to 30-90 DEG C, fore-running column overhead temperatures can be set to 100-115 DEG C, and primary distillation tower column bottom temperature can be set to 120-160℃.Primary distillation tower tower top pressure can be set to 0-0.03MPa, and tower bottom pressure can be set to 0-0.35MPa. The temperature and pressure of primary distillation tower can by adjusting charging temperature and pressure, boil ratio, reflux ratio again etc. and be adjusted and be arranged.

In a preferred embodiment, stripping reaction tower bottom of tower can be without reboiler, and stripping reaction column overhead can be with Frozen-free reflux.

Description of the drawings

The following drawings of the utility model is used to understand the utility model in this as the part of the utility model.Attached drawing In show the embodiments of the present invention and its description, for explaining the principles of the present invention.

Fig. 1 is that a kind of utilization lignocellulose raw material described in an embodiment according to the present utility model is continuously made The schematic diagram of the system of standby furfural.

Fig. 2 is a kind of continuous using lignocellulose raw material described in another embodiment according to the present utility model Prepare the schematic diagram of the system of furfural.

Specific implementation mode

In the following description, a large amount of concrete details are given more thoroughly to manage in order to provide to the utility model Solution.It will be apparent, however, to one skilled in the art that the utility model may not need it is one or more of these thin It saves and is carried out.In other examples, in order to avoid obscuring with the utility model, for more well known in the art Technical characteristic is not described.

Fig. 1 diagrammatically illustrates an embodiment according to the present utility model.

As shown in Figure 1, it is a kind of system continuously preparing furfural using lignocellulose raw material, including acid solution exports Unit 10, raw material mixed cell 20, feed unit 30, main body reaction member 40, discharging unit 50 strip reaction tower 60, steam Outlet 61, the first feed(raw material)inlet 62, stripped vapor entrance 63, acid solution outlet 64, separative element 70, purification unit 80.

The system can continuously prepare furfural with following technology utilization lignocellulose raw materials.

The first acid solution that lignocellulose raw material exports in raw material mixed cell 20 with acid solution output unit 10 is with one Certainty ratio is uniformly mixed and forms mixture.Mixture is continuously fed into feed unit 30, and feed unit 30 presses mixture Contract conveying mixture outward.Mixture continuously and stably enters main body reaction member 40, and under the pressure higher than normal pressure Reach the solid-to-liquid ratio of setting so that it is reacted with the second acid solution mixing that acid solution output unit 10 exports.Generation after the completion of reaction Object is continuously and stably delivered to discharging unit 50, and product is separated by solid-liquid separation in discharging unit 50, and the liquid of output is Pentose solution containing acid.It is heated by the heaters first containing sour pentose solution from 60 top of stripping reaction tower to the first temperature Feed(raw material)inlet 62 enters in tower, and the stripped vapor of second temperature enters tower from the stripped vapor entrance 63 of 60 bottom of stripping reaction tower Interior, cyclodehydration reaction occurs in stripping reaction tower 60 and generates furfural for the pentose solution containing acid, and acid is catalyst, then, raw At furfural produced from the steam (vapor) outlet 61 at stripping reaction tower 60 top with steam, acid solution of the acid solution from 60 bottom of stripping reaction tower 64 extraction of outlet；The steam containing furfural of extraction enters the separative element 70 being connected with stripping reaction tower 60, in separative element 70 Acid in steam containing furfural is neutralized, and obtains the steam containing furfural of acid content reduction；The steam containing furfural that acid content reduces enters The purification unit 80 being connected with separative element 70, and be purified in purification unit 80.

In a preferred embodiment, raw material mixed cell 20 may include ribbon mixer, be used for raw material It is uniformly mixed under auger effect with the first acid solution and forms mixture, and continuous feed is provided to feed unit 30.It adopts Raw material and acid solution can be made to mix more uniform with ribbon mixer, it is ensured that sequential hydrolysis reaction is smoothed out.

In a preferred embodiment, feed unit 30 may include the feeding screw with compression function, preferably Feeding screw includes compression section, and compression section internal diameter and screw pitch are tapered into along feedstock direction, and more preferable feeding screw includes Material plug section, material plug section is located at after compression section and internal diameter and screw pitch remain unchanged.Feeding screw, for pressing mixture It contracts and mixture is transported to main body reaction member 40.Hydrolysis in main body reaction member 40 is under conditions of higher than normal pressure It carries out, the feeding screw of feed unit 30 can ensure that the material in main body reaction member 40 counter will not leap up back into material unit 30, and pressure stability in main body reaction member 40 is maintained, ensure the hydrolysis in main body reaction member 40 in stable pressure It is carried out under power；In addition, by using feeding screw, moreover it is possible to which offer is continuously and stably fed, and is not in clogging.

In a preferred embodiment, feed unit 30 can also include respectively with raw material mixed cell 20 and spiral First taper tremie pipe of feeder connection, for receiving the mixture from raw material mixed cell 20, and be conveyed to spiral into Glassware.Received using the first taper tremie pipe in feed unit 30 and convey mixture, it can be ensured that mixture successfully into Enter feeding screw, to can avoid because from raw material mixed cell 20 export uniformly mixed mixture mobility it is poor and Caused blocking conveys unsmooth.

In a preferred embodiment, main body reaction member 40 may include helical reactors, the helical reactors For flat-pushing streaming and without compression function.Hydrolysis, spiral shell occur in the helical reactors of main body reaction member 40 for mixture Rotation reactor is when being set as laminar flow, to complete the reaction and can improve reaction efficiency so that the mixture in reactor exists Arbitrary stage of reaction solid-liquid mixing ratio is consistent, improves the efficiency of hydrolysis.

In a preferred embodiment, main body reaction member 40 can also include connecting, being used for feed unit 30 The second taper tremie pipe of mixture is received, is additionally provided at the top of the second taper tremie pipe and is connect with acid solution output unit 10 Acid solution adding set, for add the second acid solution.It is received using the second taper tremie pipe and defeated in main body reaction member 40 It send mixture that can ensure that mixture smoothly enters helical reactors, avoids the solidliquid mixture stream exported from feed unit 30 It blocks or conveys unsmooth caused by dynamic property is poor；It is further mended in the acid solution adding set that the top of the second taper tremie pipe is arranged The acid solution needed for reaction is filled to reach the solid-to-liquid ratio of setting so that hydrolysis can be carried out efficiently.

In a preferred embodiment, acid solution adding set can add the second acid solution by spray.Using spray Mode can the second acid solution be more uniformly sprayed to the mixture from feed unit 30, additionally aid the second acid solution and mixed Close the uniform mixing of object.

In a preferred embodiment, main body reaction member 40 can also include vapor inlet port, be used to receive High-temperature steam.The reaction temperature that steam input is able to maintain that main body reaction member 40 avoids temperature from declining in suitable range Caused by reaction rate reduce.

In a preferred embodiment, main body reaction member 40 can also include blow valve, reaction process is discharged The fixed gas of middle generation.In such manner, it is possible to ensure pressure in main body reaction member 40 in suitable range, so that hydrolysis Stable reaction carries out.

In a preferred embodiment, the temperature and pressure of main body reaction member 40 can be for example, by adjustment charging Temperature and pressure controls the modes such as blow valve to be adjusted and be arranged.Main body reaction member 40 can be configured to temperature 100-200 DEG C, pressure 0.1-1.8MPa；Preferably, temperature is 100-160 DEG C, pressure 0.1-0.8MPa；It is highly preferred that Temperature is 115-125 DEG C, pressure 0.15-0.25MPa；Most preferably, temperature is 120 DEG C, pressure 0.2MPa.

In a preferred embodiment, discharging unit 50 may include the spiral discharging device with compression function, spiral Discharger is used to carry out squeezing filtering and separation of solid and liquid to product.It is preferred that spiral discharging device includes compression section, compression section internal diameter It is tapered into along discharging direction with screw pitch；More preferable spiral discharging device further includes material plug section, material plug section be located at compression section later and Internal diameter and screw pitch remain unchanged；There are sieve, spiral discharging device that liquid is discharged by sieve at more preferable spiral discharging device wall；Spiral shell Screwing out glassware end has solids discharge mouth for solid to be discharged.The spiral discharging device of discharging unit 50 can ensure to export product During material spray will not occur, be able to maintain that pressure stability in main body reaction member 40；Additionally it is capable of providing continuous-stable Ground discharges, and is not in clogging.

In a preferred embodiment, the temperature of the first acid solution is preferably 40-95 DEG C, more preferably 55-65 DEG C, most Preferably 60 DEG C；The temperature of second acid solution is preferably 110-200 DEG C, more preferably 125-135 DEG C, most preferably 130 DEG C.It is any Within the scope of capable of realizing the acid concentration of lignocellulosic hydrolysis the utility model the considerations of, in a preferred embodiment In, the acid concentration of the first acid solution and/or the second acid solution can be 0.1wt%-10wt%.

In a preferred embodiment, being added to the second acid solution of main body reaction member 40 can also be such that solid-liquid mixes Object reaches the solid-liquid mass ratio of setting, and preferably solid-liquid mass ratio is 1:3-1:8.

In a preferred embodiment, the temperature and pressure in raw material mixed cell 20 and in feed unit 30 It is adjusted and is arranged for example, by adjusting the modes such as the temperature and pressure fed.Raw material mixed cell 20 can be arranged to temperature Degree is 40-90 DEG C, and pressure is normal pressure；It is 40-90 DEG C that feed unit 30, which can be arranged to temperature,.

In a preferred embodiment, the first acid solution can be the acid solution and the second acid from acid solution outlet extraction Liquid may be the acid solution from acid solution outlet extraction.Acid cycle utilization can reduce the processing cost of acid solution, and can subtract Few environmental pollution.

In a preferred embodiment, separative element 70 can also include filter device, and preferably ceramic filter should Filter device is for being filtered the steam containing furfural that acid content reduces, further to remove the impurity in steam containing furfural. The use of filter device can effectively reduce the yield of the aldehyde mud in follow-up Furfural Treating Process, extend fore-running tower reboiler and change The service life of hot cell.

In a preferred embodiment, which can also include heat exchange unit, the heat exchange unit Including：Material channel and furfural channel.Material channel receives the pentose solution containing acid as raw material, and furfural channel reception, which comes from, to be divided Steam containing furfural from unit 70.Pentose solution containing acid and steam containing furfural lead to respectively by material channel and furfural channel It is mutually isolated but can make the pentose solution containing acid and steam containing furfural to carry out heat exchange between road, respectively by gained after heat exchange Pentose solution containing acid and furfuryl aldehyde solution be sent into stripping reaction tower 60 and purification unit 80.It can be effectively using heat exchange unit The temperature that the pentose solution containing acid is improved using the heat of the steam containing furfural, can faster be reached reaction temperature, avoided The waste of energy.

In a preferred embodiment, purification unit 80 may include：Primary distillation tower has the fore-running positioned at middle part Tower feed inlet, the primary distillation tower steam (vapor) outlet positioned at top and aqueous phase liquid entrance boil steam inlet and fore-running again positioned at bottom Tower bottom liquid exports；Furfuryl aldehyde solution heat exchanger, furfuryl aldehyde solution are cooled to third temperature through primary distillation tower through furfuryl aldehyde solution heat exchanger Feed inlet enters primary distillation tower；It is furnished with condensation reflux unit equipped with fore-running tower reboiler, tower top in primary distillation tower bottom of tower；Condensation reflux unit Including primary distillation tower condenser and primary distillation tower liquid separation tank；A part of bottom liquid becomes after the heat exchange of fore-running tower reboiler boils steam again Primary distillation tower is returned through boiling steam inlet again；Primary distillation tower condenser is connected with primary distillation tower steam (vapor) outlet, for by containing after purification Furfural steam is condensed to the condensate liquid of the 4th temperature；Primary distillation tower liquid separation tank, is connected with primary distillation tower condenser, for receiving condensation Liquid carries out liquid separation to obtain aqueous phase liquid and oil phase liquid, and sends aqueous phase liquid back to primary distillation tower through aqueous phase liquid entrance, will be oily The output of phase liquid is used as chaff aldehyde product.

In a preferred embodiment, separative element 70 may include lye input port to input the alkali for neutralization Liquid avoids acid from making furfural decomposition or polycondensation in subsequent processing to neutralize the acid in steam containing furfural.

In a preferred embodiment, the separation method of separative element 70 can be inertial separation, be separated by filtration, from One or more of heart separation, the utility model preferably using the cyclone separator of centrifugal separation method is belonged to, be used for by Salt and solid impurity are detached with steam containing furfural, to provide the steam containing furfural of acid content reduction.Cyclone separator has structure Be simple and convenient to operate, high temperature resistant, long lifespan the advantages that.

In a preferred embodiment, this prepare furfural system can also include acid solution heat exchanger, for receive from The acid solution of 64 extraction of acid solution outlet of 60 bottom of stripping reaction tower simultaneously carries out thermal energy recycling.

In a preferred embodiment, purification unit 80 can also include refining plant, for chaff aldehyde product Be dehydrated and take off light refined to obtain product furfural.

In a preferred embodiment, purification unit 80 further includes waste water evaporator, for discharge primary distillation tower A part for bottom liquid is evaporated recycling.

In a preferred embodiment, the first temperature can be 80-155 DEG C, and second temperature can be 150-220 DEG C, 60 tower top temperature of stripping reaction tower can be 140-210 DEG C, and column bottom temperature can be 150-220 DEG C, strip 60 tower of reaction tower Pressure on top surface can be 0.26-2.2MPa (gauge pressure), and tower bottom pressure can be 0.37-2.2MPa (gauge pressure).Strip reaction tower 60 Temperature and pressure can be adjusted and be arranged by adjusting temperature and pressure of charging etc..

In a preferred embodiment, third temperature can be 20-100 DEG C, and the 4th temperature can be 30-90 DEG C, Fore-running column overhead temperatures can be 100-115 DEG C, and primary distillation tower column bottom temperature can be 120-160 DEG C；Primary distillation tower tower top pressure can Think that 0-0.03MPa (gauge pressure), tower bottom pressure can be 0-0.35MPa (gauge pressure).The temperature and pressure of primary distillation tower can pass through tune The temperature and pressure of whole charging boils ratio, reflux ratio etc. to be adjusted and be arranged again.

In a preferred embodiment, stripping 60 bottom of tower of reaction tower is without reboiler, and stripping 60 tower top of reaction tower is without cold Solidifying reflux.

Fig. 2 diagrammatically illustrates a preferred embodiment according to the present utility model.Wherein, a kind of utilization is provided The system that lignocellulose raw material continuously prepares furfural, including acid solution output unit 10, raw material mixed cell 20, thread mixing Device 21, feed unit 30, feeding screw 31, the first taper tremie pipe 32, main body reaction member 40, helical reactors 41, the Two taper tremie pipes 42, acid solution adding set 43, vapor inlet port 44, blow valve 45, discharging unit 50, spiral discharging device 51, Liquid glucose collecting tank 52, slag ladle 53 strip reaction tower 60, steam (vapor) outlet 61, the first feed(raw material)inlet 62, stripped vapor entrance 63, acid Liquid outlet 64, separative element 70, ceramic filter 71, cyclone separator 72, lye input port 73, purification unit 80, primary distillation tower Reboiler 81, primary distillation tower 82, primary distillation tower feed inlet 83, primary distillation tower steam (vapor) outlet 84, aqueous phase liquid entrance 85, primary distillation tower condenser 86, primary distillation tower liquid separation tank 87, refining plant 88, primary distillation tower bottom liquid outlet 89, heat exchange unit 90, the second feed(raw material)inlet 91, Material outlet 92, furfural entrance 93, furfural outlet 94, furfuryl aldehyde solution heat exchanger 95, acid solution heat exchanger 110, waste water evaporator 120。

The device can continuously prepare furfural with following techniques.

Lignocellulose raw material is continuously fed into raw material mixed cell 20, and wherein the raw material mixed cell 20 includes spiral Mixer 21, raw material is in ribbon mixer 21 with the first acid solution (as shown by arrow A) from acid solution output unit 10 with one Certainty ratio is uniformly mixed, to form mixture and continuous output mixture.

Uniformly mixed solidliquid mixture enters feed unit 30 comprising feeding screw 31 and the first taper tremie pipe 32；The mixture continuously enters feeding screw 31 by the first taper tremie pipe 32, feeding screw 31 with compression function, Including compression section and material plug section, compression section internal diameter and screw pitch tapers into along feedstock direction, material plug section be located at compression section later and Internal diameter and screw pitch remain unchanged.Feeding screw can compress solidliquid mixture and be exported outward to main body reaction member 40。

Main body reaction member 40 is defeated including helical reactors 41, the second taper tremie pipe 42, acid solution adding set 43, steam Entrance 44 and blow valve 45.Mixture from feeding screw 31 is admitted to the second taper tremie pipe 42.Mixture is second In taper tremie pipe 42 and from acid solution output unit 10 and by the acid solution addition at the top of the second taper tremie pipe 42 is arranged The second acid solution that device 43 is added and (is preferably added by spraying) continues the solid-liquid that mixing reaches setting (as indicated by the arrows) Than subsequently into helical reactors 41, being sufficiently stirred and mixing under the pressure higher than normal pressure, to be reacted.Spiral response Device 41 is preferably flat-pushing streaming and without compression function.The high temperature of second acid solution is capable of providing the heat needed for reaction.

Vapor inlet port 44 can input steam to make up thermal loss to helical reactors 41.It, can root in reaction process Blow valve 45 is opened in due course according to the pressure change in helical reactors 41, discharges fixed gas, it is ensured that system pressure is stablized.

Product after the completion of reaction enters discharging unit 50.The discharging unit 50 includes the spiral discharging with compression function Device 51, liquid glucose collecting tank 52, slag ladle 53, spiral discharging device 51 include compression section and material plug section, and compression section is along discharging direction internal diameter It is tapered into screw pitch, material plug section is located at after compression section and internal diameter and screw pitch remain unchanged.Wherein, product is in spiral discharging It is separated by solid-liquid separation under the squeezing action of device 51.There are sieve, spiral discharging device to pass through sieve discharge liquor at spiral discharging device wall Body, liquid are the pentose solution containing acid, which enters liquid glucose collecting tank 52；Spiral discharging device end has solids discharge mouth to be used for Solid is discharged, which enters slag ladle 53.

The stripped vapor of second temperature enters from the stripped vapor entrance 63 of 60 bottom of stripping reaction tower in tower, the first temperature The pentose solution containing acid enter in tower from first feed(raw material)inlet 62 at stripping reaction tower 60 top, the pentose solution containing acid is in vapour It carries and cyclodehydration reaction generation furfural occurs in reaction tower 60, acid is catalyst, and then, the furfural of generation is anti-from stripping with steam The steam (vapor) outlet 61 at 60 top of tower is answered to produce, acid solution is produced from the acid solution outlet 64 of 60 bottom of stripping reaction tower, the acid solution of extraction A part through acid solution heat exchanger 110 exchange heat, carry out thermal energy recycling, be admitted to ribbon mixer 21 as the first acid solution later, Remaining part is fed directly into acid solution adding set 43 as the second acid solution, for supplementing acid solution and providing thermal energy.

The steam containing furfural of extraction enter with the separative element 70 that is connected of stripping reaction tower 60, lye is from lye input port 73 Into separative element 70, neutralize the acid in steam containing furfural, then steam enter cyclone separator 72 will neutralize obtained salt with The steam containing furfural that the isolated acid content of steam containing furfural reduces, the steam containing furfural that acid content reduces continue through ceramic mistake Filter 71 further removes the impurity in steam, prevents steam from coking and reducing the generation of aldehyde mud in follow-up heat transfer process.

Steam containing furfural enters heat exchange unit 90 by furfural entrance 93, and the pentose solution containing acid passes through the second feed(raw material)inlet 91 enter heat exchange units 90, the pentose solution containing acid and steam containing furfural respectively by material channel and furfural channel, channel it Between be mutually isolated but can make the pentose solution containing acid and steam containing furfural to carry out heat exchange, after heat exchange containing sour pentose solution Stripping reaction tower 60 is entered by the first feed(raw material)inlet 62 after the output of material outlet 92, the furfuryl aldehyde solution of gained is from chaff after heat exchange 94 output of aldehyde outlet.

Then, furfuryl aldehyde solution enters the purification unit 80 being connected with separative element 70, and furfuryl aldehyde solution is through furfuryl aldehyde solution first Heat exchanger 95 is cooled to third temperature, then from primary distillation tower feed inlet 83 enter primary distillation tower 82, in primary distillation tower 82 after purification from The steam containing furfural of the extraction of primary distillation tower steam (vapor) outlet 84 of tower top after purification, then, steam containing furfural after purification enters fore-running Tower condenser 86 carries out being cooled to the 4th temperature, is then fed to primary distillation tower liquid separation tank 87, the liquid separation in primary distillation tower liquid separation tank 87 Aqueous phase liquid and oil phase liquid are obtained, aqueous phase liquid is back to by aqueous phase liquid entrance 85 in primary distillation tower 82, and oil phase liquid is defeated Go out as chaff aldehyde product；A part of bottom liquid of 89 extraction of primary distillation tower bottom liquid outlet exchanges heat through fore-running tower reboiler 81 Become afterwards and boil steam again, returns to primary distillation tower 82 through boiling steam inlet again, rest part bottom liquid is produced as waste water.

In a preferred embodiment, purification unit 80 can also include refining plant 88, for being produced to chaff aldehyde Object be dehydrated and take off light refined to obtain product furfural.

In a preferred embodiment, which can also include waste water evaporator 120, for a part of fore-running 82 bottom liquid of tower is evaporated recycling.

In a preferred embodiment, the first temperature can be set to 80-155 DEG C, and second temperature can be set It is set to 150-220 DEG C, tower top temperature can be set to 140-210 DEG C, and stripping 60 column bottom temperature of reaction tower can be set to 150-220 DEG C, tower top pressure can be set to 0.26-2.2MPa (gauge pressure), and tower bottom pressure can be set to 0.37- 2.2MPa (gauge pressure).Strip reaction tower 60 temperature and pressure can by adjusting temperature and pressure of charging etc. being adjusted and Setting.

In a preferred embodiment, third temperature can be set to 20-100 DEG C, and the 4th temperature can be set It is set to 30-90 DEG C, tower top temperature can be set to 100-115 DEG C, and column bottom temperature can be set to 120-160 DEG C；Fore-running 82 tower top pressure of tower can be set to 0-0.03MPa (gauge pressure), and tower bottom pressure can be set to 0-0.35MPa (gauge pressure). The temperature and pressure of primary distillation tower 82 can by adjusting charging temperature and pressure, boil ratio and reflux ratio again etc. and be adjusted and set It sets.

Embodiment

Using system as shown in Figure 2, furfural is continuously prepared using lignocellulose raw material.

Lignocellulose raw material is continuously fed into raw material mixed cell 20, and wherein the raw material mixed cell 20 includes spiral Mixer 21, raw material are uniformly mixed with the first acid solution (as shown by arrow A) with certain proportion in ribbon mixer 21, to be formed Mixture and continuous output mixture, the first acid solution are a part for the acid solution for stripping 60 bottom of tower of reaction tower, and are changed through acid solution The heat exchange of hot device 110 cools to 60 DEG C.

Uniformly mixed solidliquid mixture enters feed unit 30 comprising feeding screw 31 and the first taper tremie pipe 32；The mixture continuously enters feeding screw 31 by the first taper tremie pipe 32, feeding screw 31 with compression function, Including compression section and material plug section, compression section internal diameter and screw pitch tapers into along feedstock direction, material plug section be located at compression section later and Internal diameter and screw pitch remain unchanged, and feeding screw 31 can compress solidliquid mixture and be exported outward to main body reaction member 40。

Main body reaction member 40 is defeated including helical reactors 41, the second taper tremie pipe 42, acid solution adding set 43, steam Entrance 44 and blow valve 45.Mixture from feeding screw 31 is admitted to the second taper tremie pipe 42.Mixture is second Continue with the second acid solution to mix the solid-to-liquid ratio for reaching setting (as indicated by the arrows) in taper tremie pipe 42, the second acid solution is stripping A part for the acid solution of 60 bottom of tower of reaction tower, by be arranged the acid solution adding set 43 at the top of the second taper tremie pipe 42 into Row addition (is preferably added by spraying), enters helical reactors 41 after solid-liquid mixing, under the pressure higher than normal pressure fully Stirring and mixing, to be reacted.Helical reactors 41 are preferably flat-pushing streaming and without compression function.Second acid solution without Heat exchange cooling, the high temperature itself having are capable of providing the temperature needed for reaction.

Vapor inlet port 44 can input steam to make up thermal loss to helical reactors 41.It, can root in reaction process Blow valve 45 is opened in due course according to the pressure change in helical reactors 41, discharges fixed gas, it is ensured that system pressure is stablized.

Product after the completion of reaction enters discharging unit 50.The discharging unit 50 includes the spiral discharging with compression function Device 51, liquid glucose collecting tank 52, slag ladle 53, spiral discharging device 51 include compression section and material plug section, and compression section internal diameter and screw pitch edge go out Material direction tapers into, and material plug section is located at after compression section and internal diameter and screw pitch remain unchanged.Wherein, product is in spiral discharging It is separated by solid-liquid separation under the squeezing action of device 51.Filtered solid material is further processed after continuously entering slag ladle 53.By After the pentose solution containing acid of filter is collected by collecting tank 52, the filtered steam containing furfural with stripping 60 overhead extraction of reaction tower The heat exchange in heat exchange unit 90, the pentose solution containing acid enter stripping from the first feed(raw material)inlet 62 after being preheated to 150 DEG C and react Tower 60, the stripped vapor that temperature is 180 DEG C are input to from stripped vapor entrance 63 in stripping reaction tower 60, the stripped vapor of rising With pentose solution counter current contacting, after the pentose solution containing acid is further heated to 170 DEG C in stripping reaction tower 60, reacting Cyclodehydration reaction is carried out in tower.The furfural of generation enters stripped vapor, is gone out from the steam at 60 top of stripping reaction tower with 170 DEG C Mouth 61 produces (tower top pressure 0.74MPa), 8wt% containing furfural in the steam containing furfural of extraction.

The steam containing furfural of extraction is exported to separative element 70, gas phase neutralization is carried out with 12wt% sodium carbonate liquors, by Cyclone separator 72 detaches the salt of gained with steam containing furfural, to obtain the steam containing furfural of acid content reduction.Then, should Steam containing furfural enters ceramic filter 71, enters heat exchange unit 90 after filtering.

In heat exchange unit 90, filtered steam containing furfural is exchanged heat to obtain temperature with the pentose solution containing acid is 170 DEG C of furfuryl aldehyde solution.

Furfuryl aldehyde solution enters purification unit 80.Furfuryl aldehyde solution after furfuryl aldehyde solution heat exchanger 95 further cools to 85 DEG C from Primary distillation tower feed inlet 83 enters primary distillation tower 82, produces chaff aldehyde steam from primary distillation tower steam (vapor) outlet 84 after purification.It is cold through primary distillation tower Condenser 86 enters primary distillation tower liquid separation tank 87 after condensing to 80 DEG C, and liquid separation obtains aqueous phase liquid and oil phase liquid, wherein aqueous phase liquid It is 6wt%, the aqueous 8wt% of oil phase liquid containing aldehyde concentration.

Aqueous phase liquid is returned from 87 top of primary distillation tower liquid separation tank, and enters primary distillation tower 82, oil phase from aqueous phase liquid entrance 85 Liquid output is used as chaff aldehyde product, into chaff aldehyde storage tank.

The chaff aldehyde product through subsequent dehydration, it is de- light refined after can be used as product furfural.Furaldehyde yield is 88% (phase For the theoretical yield of the pentose solution of 5g/l).

The acid liquor temperature for stripping 64 extraction of acid solution outlet of 60 bottom of reaction tower is 175 DEG C, and a portion is changed through acid solution Hot device 110 exchanges heat, and carries out thermal energy recycling, is admitted to ribbon mixer 21 as the first acid solution later, remaining part is as the Two acid solutions are fed directly into acid solution adding set 43, for supplementing acid solution and providing thermal energy.Fore-running tower reboiler 80 is supplied by steam Heat, a part of bottom liquid of 89 extraction of primary distillation tower bottom liquid outlet becomes after the heat exchange of fore-running tower reboiler 31 boils steaming again Vapour returns to primary distillation tower 32 through boiling steam inlet again, and rest part bottom liquid is produced as waste water, and the waste water of extraction, which can enter, to give up After water evaporimeter 120, recycled after double evaporation-cooling.

The utility model is illustrated by above-described embodiment, but it is to be understood that, above-described embodiment is Purpose for illustrating and illustrating, and be not intended to limit the invention within the scope of described embodiment.In addition ability Field technique personnel are it is understood that the utility model is not limited to above-described embodiment, and introduction according to the present utility model is also More kinds of variants and modifications can be made, these variants and modifications all fall within the utility model range claimed with It is interior.The scope of protection of the utility model is defined by the appended claims and its equivalent scope.

Claims (34)

1. a kind of system continuously preparing furfural using lignocellulose raw material, wherein the system includes：

Acid solution output unit, for exporting the first acid solution and the second acid solution respectively；

Raw material mixed cell is connected with the acid solution output unit, mixed to be formed for being mixed with the first acid solution the raw material Close mixture described in object and continuous conveying；

Feed unit is connected with the raw material mixed cell, for receiving the mixture, being compressed simultaneously to the mixture The mixture is conveyed outward；

Main body reaction member is connected with the feed unit and the acid solution output unit, for receiving the mixture respectively With the second acid solution, and under higher than the pressure of normal pressure the mixture and the second acid solution are sufficiently stirred and mixed so that it is reacted；

Discharging unit is connected with the main body reaction member, for being separated by solid-liquid separation to product obtained by the reaction, and exports Pentose solution containing acid；

Strip reaction tower comprising be located at steam (vapor) outlet and first feed(raw material)inlet at top, and the stripped vapor positioned at bottom Entrance and acid solution outlet, wherein first feed(raw material)inlet is used to receive penta containing acid of the first temperature from discharging unit For sugar juice as raw material to carry out cyclodehydration reaction, the stripped vapor entrance is used to receive the stripped vapor of second temperature, The steam (vapor) outlet is for providing by the steam containing furfural obtained by the reaction, and the acid solution outlet from bottom of tower for producing acid solution；

Separative element is connected with the steam (vapor) outlet, for neutralizing the acid in steam containing furfural, and by the salt of gained and contains chaff Aldehyde steam detaches, to provide the steam containing furfural of acid content reduction；And

Purification unit is used to purify the furfural of gained.

2. system according to claim 1, which is characterized in that the raw material mixed cell includes ribbon mixer, described Ribbon mixer is used to raw material and the first acid solution being uniformly mixed under auger effect and forms the mixture, and to institute It states feed unit and continuous feed is provided.

3. system according to claim 1 or 2, which is characterized in that the feed unit includes the spiral with compression function Feeder, for the mixture compress and the mixture being transported to the main body reaction member.

4. system according to claim 3, which is characterized in that the feed unit includes mixing list with the raw material respectively First the first taper tremie pipe connected with the feeding screw, for receiving the mixing from the raw material mixed cell Object, and it is conveyed to the feeding screw.

5. system according to claim 1, which is characterized in that the main body reaction member includes helical reactors, described Helical reactors are for flat-pushing streaming and without compression function.

6. system according to claim 1 or 5, which is characterized in that the main body reaction member includes with described into material list Member connection, the second taper tremie pipe for receiving the mixture, are additionally provided at the top of the second taper tremie pipe and institute The acid solution adding set for stating the connection of acid solution output unit, for adding second acid solution.

7. system according to claim 6, which is characterized in that the acid solution adding set is by spraying addition described second Acid solution.

8. system according to claim 1, which is characterized in that the main body reaction member further includes vapor inlet port, For receiving high-temperature steam.

9. the system according to claim 1 or 8, which is characterized in that the main body reaction member further includes blow valve, with row Go out the fixed gas generated in reaction process.

10. system according to claim 9, which is characterized in that the main body reaction member can be configured to temperature and be 100-200 DEG C, pressure 0.1-1.8MPa.

11. system according to claim 1, which is characterized in that the discharging unit includes that the spiral with compression function goes out Glassware, the spiral discharging device are used to carry out squeezing filtering and separation of solid and liquid to the product.

12. system according to claim 1, which is characterized in that the temperature of the first acid solution is 40-95 DEG C；Second acid solution Temperature is 110-200 DEG C；The acid concentration of first acid solution and the second acid solution is 0.1-10wt%.

13. system according to claim 1, which is characterized in that the main body reaction member can be configured to temperature and be 100-200 DEG C, pressure 0.1-1.8MPa.

14. system according to claim 1, which is characterized in that the raw material mixed cell can be configured to temperature and be 40-90 DEG C, pressure is normal pressure；It is 40-90 DEG C that the feed unit, which can be configured to temperature,.

15. system according to claim 1, which is characterized in that first acid solution is from acid solution outlet extraction Acid solution.

16. system according to claim 1, which is characterized in that second acid solution is from acid solution outlet extraction Acid solution.

17. system according to claim 3, which is characterized in that the feeding screw includes compression section, the compression section Internal diameter and screw pitch are tapered into along feedstock direction.

18. system according to claim 17, which is characterized in that the feeding screw further includes material plug section, the material Plug section is located at after the compression section and internal diameter and screw pitch remain unchanged.

19. system according to claim 11, which is characterized in that the spiral discharging device includes compression section, the compression Section internal diameter and screw pitch are tapered into along discharging direction.

20. system according to claim 19, which is characterized in that the spiral discharging device further includes material plug section, the material Plug section is located at after the compression section and internal diameter and screw pitch remain unchanged.

21. system according to claim 11, which is characterized in that have sieve, the spiral shell at the spiral discharging device wall It screws out glassware and liquid is discharged by the sieve；The spiral discharging device end has solids discharge mouth for solid to be discharged.

22. system according to claim 1, wherein the separative element further includes filter device, which is used for The steam containing furfural reduced to the acid content is filtered, to provide filtered steam containing furfural.

23. according to the system described in claims 1 or 22, wherein the system further includes heat exchange unit comprising：

Material channel, including the second feed(raw material)inlet, the second feed(raw material)inlet are used to receive penta containing acid of the temperature less than the first temperature Sugar juice；And material outlet, the material outlet are connected with first feed(raw material)inlet, for being carried to the stripping reaction tower For the pentose solution containing acid of the first temperature, and

Furfural channel is mutually isolated with material channel but can carry out heat exchange, and includes furfural entrance, furfural entrance and institute It states separative element to be connected, for receiving the steam containing furfural from separative element；It is exported with furfural, furfural outlet and the purifying Unit is connected, for providing furfuryl aldehyde solution.

24. system according to claim 23, wherein the purification unit includes：

There is primary distillation tower primary distillation tower feed inlet, primary distillation tower steam (vapor) outlet and aqueous phase liquid positioned at top positioned at middle part to enter Mouth boils steam inlet and the outlet of primary distillation tower bottom liquid again positioned at bottom；

Furfuryl aldehyde solution heat exchanger, furfuryl aldehyde solution are cooled to third temperature through furfuryl aldehyde solution heat exchanger and enter just through primary distillation tower feed inlet Evaporate tower；

It is furnished with condensation reflux unit equipped with fore-running tower reboiler, tower top in the primary distillation tower bottom of tower；The condensation reflux unit includes Primary distillation tower condenser and primary distillation tower liquid separation tank；

The fore-running tower reboiler becomes after being used to exchange heat a part of bottom liquid boils steam again, is returned through boiling steam inlet again Primary distillation tower；

Primary distillation tower condenser is connected with primary distillation tower steam (vapor) outlet, for condensing steam containing furfural after purification to the 4th temperature The condensate liquid of degree；

Primary distillation tower liquid separation tank, is connected with primary distillation tower condenser, for receiving the condensate liquid, carries out liquid separation to obtain water phase liquid Body and oil phase liquid, and send the aqueous phase liquid back to primary distillation tower through the aqueous phase liquid entrance, the oil phase liquid is exported As chaff aldehyde product.

25. system according to claim 1, wherein the separative element includes that lye input port is used for inputting lye Neutralize the acid in steam containing furfural.

26. system according to claim 1, wherein the separative element includes cyclone separator, for by the salt with Steam containing furfural detaches, to provide the steam containing furfural of acid content reduction.

27. system according to claim 1, wherein the system also includes acid solution heat exchangers, for receiving from the acid The acid solution of liquid outlet outflow simultaneously carries out thermal energy recycling.

28. system according to claim 24, wherein the purification unit further includes refining plant, for described thick Furfural product be dehydrated and take off light refined to obtain product furfural.

29. system according to claim 24, wherein the system also includes waste water evaporator, the waste water evaporator It is connected with the outlet of primary distillation tower bottom liquid, for being steamed to another part bottom liquid exported from primary distillation tower bottom liquid Hair recycles.

30. system according to claim 1, wherein first temperature can be arranged to 80-155 DEG C, and described second Temperature can be arranged to 150-220 DEG C, and stripping reaction column overhead temperatures can be arranged to 140-210 DEG C, strip reaction tower Column bottom temperature can be arranged to 150-220 DEG C.

31. system according to claim 1, wherein in terms of gauge pressure, the stripping reaction tower tower top pressure can be set For 0.26-2.2MPa, stripping reaction tower tower bottom pressure can be arranged to 0.37-2.2MPa.

32. system according to claim 24, wherein the third temperature can be arranged to 20-100 DEG C, the 4th temperature Degree can be arranged to 30-90 DEG C, and fore-running column overhead temperatures can be arranged to 100-115 DEG C, and primary distillation tower column bottom temperature can It is arranged to 120-160 DEG C.

33. system according to claim 24, wherein in terms of gauge pressure, the primary distillation tower tower top pressure can be arranged to 0-0.03MPa, tower bottom pressure can be arranged to 0-0.35MPa.

34. system according to claim 1, wherein the stripping reaction tower bottom of tower is without reboiler, stripping reaction column overhead Frozen-free reflux.