System and method for producing organic acid through oxidation of electroreduction coupled waste biomass

Abstract

In the system, a cathode module comprises a first upstream raw material part, a first midstream electrolysis part and a first downstream product purification treatment part, and an anode module comprises a second upstream raw material part; and a second midstream electrolysis part and a second downstream product purification treatment part, so that the purposes of electrolyzing the industrial waste gas and generating high-value organic acid are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of carbon dioxide electroreduction, in particular to a system for electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass to produce organic acid. Background Art

[0002] Industrial waste gas refers to the waste gas containing carbon dioxide (CO 2 ), carbon monoxide (CO) and other pollutants. The carbon-containing gases are eventually converted into carbon dioxide and released into the atmosphere, which will lead to a series of environmental deterioration problems such as greenhouse effect and global warming.

[0003] Carbon capture, carbon storage, and carbon utilization together constitute CCUS technology to effectively reduce carbon emissions and achieve industrial decarbonization. Carbon utilization technology, as a key link, affects the operation of the complete carbon cycle. 2 Suitable containers and terrain are needed for storage, but these spaces are often limited. The solution to sustainable decarbonization is to consume it in some way and return it to the carbon cycle in other forms. Among them, electrocatalytic reduction of carbon dioxide has a very broad application prospect due to its mild conditions, controllable products and the ability to be driven by green electricity.

[0004] During the electrolysis of carbon dioxide, the main product at the cathode of the electrolytic cell is CO 2 CO generated by reduction; the basic product at the anode is OH in the solution - Oxygenated O 2 The oxygen evolution reaction has a low utilization value due to its high electrode potential and slow process, so replacing it with a value-added anode reaction is a new strategy; choosing a suitable reaction pair can not only reduce the reaction electrode potential and thus increase the reaction rate, but also generate high value-added products, ultimately improving the energy utilization efficiency and economic benefits of the entire electrolytic cell system.

[0005] Biomass conversion is an important way to utilize carbon sources. It replaces non-renewable fossil fuels to produce high-value-added chemical products to meet the growing demand for energy and chemical consumables. The existing waste biomass is huge and has good potential for resource utilization. Among them, wood cellulose resources are extensive and can be obtained from waste biomass such as waste paper, logging residues and crop straw. 5-Hydroxymethylfurfural (HMF) as an important basic compound can be obtained through cellulose depolymerization and further converted into raw materials for the production of various medicines, fuels and polymer materials, such as maleic acid (MA), formic acid (HCOOH) and 2,5-furandicarboxylic acid (FDCA). MA is mainly used in pharmaceuticals, synthetic resins and oil preservatives; HCOOH is the most basic organic chemical raw material and is widely used in various industrial fields; FDCA has great application potential and can produce degradable plastics. It is a green and renewable substitute for terephthalic acid and can also be used to synthesize new materials.

[0006] The information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0007] In view of the shortcomings or defects of the above-mentioned prior art, a system and method for producing organic acids by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass is provided, which couples electroreduction of carbon-containing flue gas with oxidation of waste biomass to generate high value-added products.

[0008] The purpose of the present invention is achieved through the following technical solutions.

[0009] A system for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass comprises a cathode module and an anode module. The cathode module comprises a first upstream raw material part, a first midstream electrolysis part and a first downstream product purification processing part, wherein: The first upstream raw material section includes: The exhaust tower treats carbon-containing industrial waste gas through desulfurization, denitrification and deoxygenation to discharge CO 2 gas, CO 2 A buffer tank is connected to the waste gas tower to store the carbon-containing industrial waste gas after treatment and recovery of CO 2 gas; The first midstream electrolysis section includes: The cathode electrolyte buffer tank stores the cathode electrolyte that has not participated in the reaction and is recovered. The cathode stirring tank is connected to the CO 2 The buffer tank and the catholyte buffer tank are stirred to make the CO 2 Mix well with the cathode electrolyte, A flow-type electrolytic cell is connected to the cathode stirring tank and performs electrocatalytic reduction of CO at the cathode. 2 ; The first downstream product purification treatment section includes: Flash separator I, which is connected to the flow-type electrolytic cell to separate the gas-liquid products after the reaction to obtain a mixed liquid and a mixed gas, CO 2 A capture tower connected to the flash separator I to capture and separate CO from the mixed gas 2 , CO 2 A purification tower, one end of which is connected to a CO 2 The capture tower, with the other end connected to CO 2 The CO after purification and separation in the buffer tank 2 To recover CO 2 gas, A pressure swing adsorption device is connected to the CO 2 The capture tower separates CO 2 Separate CO from the mixed gas. A CO purification tower is connected to a pressure swing adsorption device to purify the separated CO. The CO buffer tank is connected to the CO purification tower to store the separated CO product. a distillation column I connected to a flash separator I for distilling and separating the cathode electrolyte, a cathode electrolyte purification tower, one end of which is connected to the distillation tower I and the other end of which is connected to the cathode electrolyte buffer tank to purify the separated cathode electrolyte and recover it to the cathode electrolyte buffer tank; The anode module includes a second upstream raw material part, a second midstream electrolysis part and a second downstream product purification treatment part, wherein: The second upstream raw material part includes: A cellulose solution buffer tank is used to store and process the cellulose solution obtained from the waste biomass. Reactor I, which is connected to the cellulose solution buffer tank to hydrolyze cellulose into glucose solution, Reactor II, which is connected to reactor I, isomerizes the glucose in the glucose solution into fructose. Reactor III, which is connected to reactor II to dehydrate fructose into HMF; The HMF buffer tank is connected to the reactor III to store the HMF that has not participated in the reaction and is recovered. The second midstream electrolysis section includes: Anolyte buffer tank, which stores the anolyte that has not participated in the reaction and is recovered, an anode stirring tank, one end of which is connected to the HMF buffer tank and the anolyte buffer tank for stirring to uniformly mix the HMF and the anolyte, and the other end of which is connected to the flow-type electrolytic cell for anodic oxidation of the HMF; The second downstream product purification treatment section includes: Flash separator II is connected to the flow-type electrolytic cell to separate the gas and liquid products after the reaction to obtain O 2 and the second mixed solution, O 2 The purification tower is connected to the flash separator II to purify the separated O 2 , O 2 Buffer tank, which is connected to O 2 The purification tower stores the separated O 2 , The distillation tower II is connected to the flash separator II to separate the anolyte and the mixed organic acid by distillation using the different boiling points of the second mixed liquid components. Anolyte purification tower, which is connected to distillation tower II and anolyte buffer tank to purify and separate the anolyte and recover it to the anolyte buffer tank, The extraction separation tower is connected to the distillation tower II, which uses benzene as an extractant to separate HMF and mixed organic acids. Distillation column III, which is connected to an extractive separation column to separate HMF, The HMF purification tower is connected to the distillation tower III and the HMF buffer tank, and the HMF after purification and separation is recovered to the HMF buffer tank. Distillation tower IV is connected to an extraction separation tower to separate formic acid HCOOH solution from mixed organic acids. The HCOOH purification tower is connected to the distillation tower IV to purify and separate the HCOOH solution. The HCOOH buffer tank is connected to the HCOOH purification tower to store the separated HCOOH. Distillation tower V is connected to distillation tower IV to separate maleic acid MA solution from mixed organic acid. The MA purification tower is connected to the distillation tower V, which purifies and separates the maleic acid MA solution. The MA buffer tank is connected to the MA purification tower to store the separated maleic acid MA solution.

[0010] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the waste gas tower is provided with a 2 Gas exhaust header.

[0011] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, fructose is dehydrated in reactor III to obtain 5-hydroxymethylfurfural HMF.

[0012] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the cathode module and the anode module each form a closed-loop subsystem.

[0013] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the waste biomass includes agricultural waste, waste cotton textiles and logging residues.

[0014] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, agricultural waste includes straw.

[0015] In the system for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the CO 2 The capture tower uses physical adsorption or chemical absorption to capture and separate CO from the mixed gas. 2 .

[0016] In the system for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the distillation tower I is connected to the flash separator I to distill and separate the cathode electrolyte by utilizing the different boiling points of the components of the mixed liquid.

[0017] In the system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, the distillation tower III is connected to the extraction separation tower to separate HMF by utilizing the different boiling points of HMF and the extractant benzene.

[0018] The system for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass is suitable for 2 Other electrode reactions and product combinations with HMF as raw materials.

[0019] The method for treating a system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass comprises the following steps: Carbon-containing industrial waste gas is desulfurized, denitrified and deoxygenated in the waste gas tower and discharged to the CO 2 Storage in buffer tanks; CO 2 CO stored in buffer tank 2 The gas and the cathode electrolyte stored in the cathode electrolyte buffer tank that has not participated in the reaction enter the cathode stirring tank to be evenly mixed, and then enter the cathode chamber of the mobile electrolytic cell to participate in the reaction; The cellulose solution obtained by treating the waste biomass is stored in the cellulose solution buffer tank, and enters the reactor I to be hydrolyzed into glucose under the action of the catalyst. The glucose solution enters the reactor II to be isomerized into fructose under the action of the catalyst. The fructose solution enters the reactor III to be dehydrated under the action of the catalyst to obtain the HMF solution, and the HMF solution enters the HMF buffer tank for storage; The HMF solution stored in the HMF buffer tank and the anolyte that has not participated in the reaction stored in the anolyte buffer tank enter the anode stirring tank together for uniform mixing, and then enter the anode chamber of the mobile electrolytic cell to participate in the reaction; The mixed solution after the reaction in the cathode chamber of the flow-type electrolytic cell enters the flash separator I to separate the gas and liquid products; The mixed liquid obtained from the flash separator I enters the distillation tower I for liquid-liquid separation, and is distilled using boiling point difference to obtain a cathode electrolyte, which is then further purified in the cathode electrolyte purification tower to obtain a cathode electrolyte, and then flows back to the cathode electrolyte buffer tank for storage; The mixed gas obtained from the flash separator I enters the CO 2 In the capture tower, physical adsorption or chemical absorption is used to capture and separate CO from the mixed gas. 2 Gas, this part of gas continues to be passed into CO 2 In the purification tower, the purified and separated CO 2 Until there are no other gas impurities, finally return to CO 2 Stored in the buffer tank and waiting for the next round of reaction; CO 2 Capture and separation of CO in a capture tower 2 The remaining mixed gas is passed into a pressure swing adsorption device, from which CO gas is separated and enters a CO purification tower, and the CO obtained by purification and separation is purified until there are no other gas impurities, and finally passed into a CO buffer tank for storage to obtain cathode product CO; The mixed solution after the reaction in the anode chamber of the flow-type electrolytic cell enters the flash separator II to separate the gas and liquid products; The mixed gas obtained from the flash separator II enters the O 2 In the purification tower, O 2 Until there are no other gas impurities, finally pass O 2 The anode byproduct O is stored in a buffer tank. 2 ; The mixed solution obtained from the flash separator II enters the distillation tower II for liquid-liquid separation, and the anolyte containing impurities is obtained by distillation using the boiling point difference, and then enters the anolyte purification tower for further purification to obtain the anolyte without other impurities, and flows back to the anolyte buffer tank for storage; The remaining mixed liquid separated from distillation tower II enters the extraction separation tower, where benzene is used as an extractant to separate the HMF component. The mixture of the extractant benzene and the solute HMF enters the distillation tower III, where benzene is first evaporated and then separated to obtain HMF, which enters the HMF purification tower to further purify the HMF until there are no other liquid impurities. Finally, it flows back to the HMF buffer tank for storage and waits for the next round of reaction. The mixed liquid after HMF removal from the extraction separation tower enters the distillation tower IV, where HCOOH is first evaporated and then enters the HCOOH purification tower for condensation and purification until there is no other impurity liquid, and finally flows into the HCOOH buffer tank for storage to obtain formic acid; The mixed liquid after HCOOH removal obtained from distillation tower IV enters distillation tower V, MA is evaporated, enters MA purification tower, condenses and purifies until there is no other impurity liquid, and finally flows into MA buffer tank for storage to obtain maleic acid.

[0020] Compared with the prior art, the present invention has the following beneficial effects: The cathode module and anode module of the system and method for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass can respectively complete the pretreatment of upstream raw materials, the electrolysis in the midstream flow-type electrolytic cell chamber, and the purification and separation of downstream products, thereby building a complete product chain. After each round of electrolysis, the raw materials are separated at the same time as the separated products, such as the CO 2 The HMF at the anode and the electrolyte at both electrodes are purified and recycled to the corresponding buffer tanks for storage and reuse, reducing the loss rate of raw materials and improving the system yield and energy utilization rate through material circulation. The process design of the cathode module and the anode module is also applicable to the CO 2 Other electrode reactions with HMF as raw materials may result in HCOOH as cathode product and FDCA as anode product or CO as cathode product and FDCA as anode product, which may be designed according to the above scheme to achieve the purpose of electrolyzing industrial waste gas and generating high-value organic acids. Two parallel closed-loop subsystems are constructed at the cathode and anode respectively to recycle and reuse raw materials, realize material circulation, and improve the overall energy efficiency of the system and the yield of high-value organic acids; the scheme design is flexible and suitable for CO 2 and other electrode reactions and product combinations using HMF as raw materials; using green electricity to drive electrolysis can promote the consumption of new energy, and the CO obtained by converting carbon-containing substances in electrolytic industrial waste gas 2 It can reduce carbon emissions and environmental pollution, and the anode produces high-value-added organic acids to improve economic benefits, thus achieving energy conservation and emission reduction results overall. 2 and anodic oxidation of waste biomass to produce high-value organic acids, which can improve CO 2 It can improve conversion rate, treat industrial waste gas and reduce carbon emissions, absorb new energy electricity, utilize waste biomass as resources and improve economic benefits, build a dual material cycle and enhance the energy utilization efficiency of the system. It has broad application prospects and good development potential.

[0021] The above description is only an overview of the technical solution of the present invention. In order to make the technical means of the present invention clearer and to achieve the extent that those skilled in the art can implement it according to the contents of the specification, and in order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are exemplified below. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0023] In the attached picture: Figure 1 It is a schematic structural diagram according to an embodiment of the present invention.

[0024] The present invention will be further explained below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0026] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0027] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0028] For a better understanding, Figure 1 As shown, a system for producing organic acid by electroreduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass includes a cathode module and an anode module with a flow electrolysis cell as an interface.

[0029] The cathode module includes a first upstream raw material part, a first midstream electrolysis part and a first downstream product purification processing part, wherein: The first upstream raw material section includes: Waste gas tower 1, which treats industrial waste gas through desulfurization, denitrification and deoxygenation, and discharges it through the exhaust head. CO 2 Buffer tank 2, which stores the CO recovered after industrial waste gas treatment 2 gas; The first midstream electrolysis section includes: The cathode electrolyte buffer tank 3 stores the cathode electrolyte that has not participated in the reaction and is recovered. The cathode stirring tank 4 is used to stir the CO 2 Mix well with the cathode electrolyte, The flow-type electrolytic cell 5 has a cathode that electrocatalytically reduces the CO obtained from the exhaust gas. 2 ; The first downstream product purification treatment section includes: Flash separator I6, which separates the gas and liquid products after the reaction. CO 2 The capture tower 7 captures and separates CO from the mixed gas by physical adsorption or chemical absorption. 2 , CO 2 Purification tower 8, which purifies the separated CO 2 , The pressure swing adsorption device 9 separates CO 2 Separate CO from the mixed gas. The CO purification tower 10 purifies the separated CO. The CO buffer tank 11 stores the separated CO product. The distillation tower Ⅰ12 uses the different boiling points of the mixed liquid components to separate the cathode electrolyte by distillation. The cathode electrolyte purification tower 13 further purifies the separated cathode electrolyte and recycles it to the cathode electrolyte buffer tank 3 for use. The anode module includes a second upstream raw material part, a second midstream electrolysis part and a second downstream product purification treatment part, wherein: The second upstream raw material part includes: The cellulose solution buffer tank 14 stores the cellulose solution obtained by processing straw, agricultural waste, waste cotton textiles, etc. Reactor I15, which hydrolyzes cellulose into glucose solution, Reactor II 16, which isomerizes glucose into fructose, Reactor III 17, which dehydrates fructose to HMF; HMF buffer tank 18, which stores HMF that has not participated in the reaction and is recovered, Second midstream electrolysis section: Anolyte buffer tank 19, which stores the anolyte that has not participated in the reaction and is recovered, The anode stirring tank 20 is used to stir the organic raw material HMF and the anode electrolyte to mix evenly. A flow-type electrolytic cell 5, the anode of which oxidizes the organic matter HMF; Second downstream product purification treatment part: Flash separator II 21, which separates the gas and liquid products after the reaction. O 2 Purification tower 22, which purifies the separated by-product O 2 , O 2 Buffer tank 23, which stores the separated by-product O 2 , The distillation tower II 24 separates the anolyte and the mixed organic acid by distillation using the different boiling points of the mixed liquid components. Anolyte purification tower 25 further purifies the separated anolyte and recycles it to anolyte buffer tank 19 for use. Extraction separation tower 26, which uses benzene as an extractant to separate HMF from the product mixed organic acid, The distillation column III 27 further separates HMF by utilizing the different boiling points between HMF and the extractant benzene. The HMF purification tower 28 purifies and separates the HMF and recycles it to the HMF buffer tank for use. The distillation tower IV 29 utilizes the different boiling points of the components in the mixed organic acid whose main components are formic acid HCOOH and maleic acid MA to first separate the product formic acid HCOOH, The HCOOH purification tower 30 further purifies the separated HCOOH solution. HCOOH buffer tank 31, which stores the separated product HCOOH, Distillation tower V32, which separates the product maleic acid MA, MA purification tower 33, which further purifies the separated MA solution, The MA buffer tank 34 stores the separated product MA.

[0030] To further illustrate the present invention, in one embodiment, the cathode module is divided into a first upstream raw material part, a first midstream electrolysis part and a first downstream product purification treatment part, wherein the first upstream raw material part includes: an exhaust tower 1, a CO 2 Buffer tank 2; the first midstream electrolysis part includes: cathode electrolyte buffer tank 3, cathode stirring tank 4, flow-type electrolytic cell 5; the first downstream product purification treatment part includes: flash separator I 6, CO 2 Capture tower 7, CO 2 Purification tower 8, pressure swing adsorption device 9, CO purification tower 10, CO buffer tank 11, distillation tower I 12, cathode electrolyte purification tower 13; the anode module is divided into a second upstream raw material part, a second midstream electrolysis part and a second downstream product purification treatment part, wherein the second upstream raw material part includes: cellulose solution buffer tank 14, reactor I 15, reactor II 16, reactor III 17, HMF buffer tank 18; the second midstream electrolysis part includes: anode electrolyte buffer tank 19, anode stirring tank 20, flow-type electrolytic cell 5; the second downstream product purification treatment part includes: flash separator II 21, O 2 Purification tower 22, O 2 Buffer tank 23, distillation tower II 24, anolyte purification tower 25, extraction separation tower 26, distillation tower III 27, HMF purification tower 28, distillation tower IV 29, HCOOH purification tower 30, HCOOH buffer tank 31, distillation tower V 32, MA purification tower 33, MA buffer tank 34. The industrial waste gas is desulfurized, denitrated and deoxygenated in the waste gas tower 1 and the generated CO is removed through the exhaust head. 2 The gas is discharged into the corresponding buffer tank 2 for storage, and enters the stirring tank 4 together with the electrolyte stored in the cathode electrolyte buffer tank 3 for uniform mixing, and then enters the cathode chamber of the electrolytic cell 5 to participate in the reaction; the anode module pre-treats the cellulose solution in the reactor I 15 to the reactor III 17 in sequence, first hydrolyzing the cellulose into glucose, isomerizing the glucose into fructose, and dehydrating the fructose to obtain 5-hydroxymethylfurfural HMF, which enters the corresponding buffer tank for storage, and enters the stirring tank 20 together with the electrolyte stored in the anode electrolyte buffer tank 19 for uniform mixing, and then enters the anode chamber of the electrolytic cell 5 to participate in the reaction; the mixed solution in the cathode chamber enters the flash separator 6 for gas-liquid separation, and the separated mixed liquid enters the distillation tower 12 to obtain the cathode electrolyte by using the boiling point difference, enters the purification tower 13 for further purification, and then is recovered to the buffer tank 3 to wait for the next round of reaction; the separated mixed gas enters the CO 2 Capture tower 7 uses physical adsorption or chemical absorption to separate CO 2 Gas, after further purification, is recovered to CO 2 Waiting for the next round of electrolysis in buffer tank 2; removing CO 2The remaining mixed gas enters the pressure swing adsorption device 9 to separate the CO gas, and after purification, it is passed into the buffer tank 11 for storage to obtain the cathode product CO; the mixed solution in the anode chamber enters the flash separator 21 for gas-liquid separation, and the separated mixed gas enters the O 2 The purification tower 22 separates and purifies O 2 , pass to O 2 In the buffer tank 23, the anode byproduct O is obtained. 2 The separated mixed liquid enters the distillation tower 24 to obtain the anolyte by using the boiling point difference, enters the purification tower 25 for further purification and then is recovered to the buffer tank 19 to wait for the next round of reaction; the remaining mixed liquid after the electrolyte is recovered enters the extraction separation tower 26, and HMF is extracted and separated by using benzene as an extractant by using the solubility difference of each component in benzene, and the mixture of the two enters the distillation tower 27 to be separated again by using the boiling point difference, and finally HMF is purified and recovered to the buffer tank to wait for the next round of electrolysis; the remaining liquid after HMF is separated is subjected to two-step distillation in the order of boiling point from low to high to successively evaporate HCOOH and MA, which are condensed and purified in the purification tower 30 and the purification tower 33 respectively and then enter the corresponding buffer tank 31 and the buffer tank 34 for storage to obtain the anode products HCOOH and MA.

[0031] According to one embodiment of the present invention, a method for treating a system for producing high-value organic acids by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass comprises: Carbon-containing industrial waste gas is desulfurized, denitrified and deoxygenated in the waste gas tower 1 and discharged to the CO 2 Storage in buffer tanks; CO 2 CO stored in buffer tank 2 2 The gas and the cathode electrolyte stored in the cathode electrolyte buffer tank 3 that has not participated in the reaction enter the cathode stirring tank 4 to be evenly mixed, and then enter the cathode chamber of the fluid electrolytic cell 5 to participate in the reaction; The cellulose solution buffer tank 14 stores and processes the cellulose solution obtained by processing straw, agricultural waste, waste cotton textiles, and logging residues, and enters the reactor I 15 to be hydrolyzed into glucose under the action of a catalyst. The glucose solution enters the reactor II 16 to be isomerized into fructose under the action of a catalyst. The fructose solution enters the reactor III 17 to be dehydrated under the action of a catalyst to obtain HMF, and the HMF solution enters the HMF buffer tank 18 for storage; The HMF solution stored in the HMF buffer tank 18 and the anolyte that has not participated in the reaction stored in the anolyte buffer tank 19 enter the anode stirring tank 20 to be evenly mixed, and then enter the anode chamber of the mobile electrolytic cell 5 to participate in the reaction; The mixed solution after the reaction in the cathode chamber of the flow-type electrolytic cell 5 enters the flash separator I 6 to separate the gas-liquid mixture; The mixed solution obtained from the flash separator I6 enters the distillation tower I12 for liquid-liquid separation, and is distilled using boiling point difference to obtain a cathode electrolyte containing a small amount of impurities, and then enters the cathode electrolyte purification tower 13 for further purification to obtain a cathode electrolyte without other impurities, and flows back to the cathode electrolyte buffer tank 3 for storage; The mixed gas obtained from the flash separator I6 enters the CO 2 In the capture tower 7, CO is captured and separated from the mixed gas by physical adsorption or chemical absorption. 2 Gas, this part of gas continues to be passed into CO 2 In the purification tower 8, the CO obtained by purification and separation is 2 Until there are no other gas impurities, finally return to CO 2 The buffer tank 2 is stored and waits for the next round of reaction; CO 2 CO is captured and separated in capture tower 7 2 The remaining mixed gas obtained is passed into the pressure swing adsorption device 9, from which the CO gas is separated and enters the CO purification tower 10, the CO obtained by purification and separation is purified until there are no other gas impurities, and finally passed into the CO buffer tank 11 for storage to obtain the cathode product CO; The mixed solution after the reaction in the anode chamber of the flow-type electrolytic cell 5 enters the flash separator II 21 to separate the gas-liquid mixture; The mixed gas obtained from the flash separator II 21 enters the O 2 In the purification tower 22, O is separated and purified. 2 Until there are no other gas impurities, finally pass O 2 The buffer tank 23 is used to store the anode byproduct O 2 ; The mixed solution obtained from the flash separator II 21 enters the distillation tower II 24 for liquid-liquid separation, and is distilled using boiling point difference to obtain an anolyte containing a small amount of impurities, and then enters the anolyte purification tower 25 for further purification to obtain an anolyte without other impurities, and flows back to the anolyte buffer tank 19 for storage; The remaining mixed liquid separated from the distillation tower II 24 enters the extraction separation tower 26. HMF has a high solubility in benzene, MA is insoluble in benzene, and HCOOH has a low solubility in benzene. Therefore, benzene can be used as an extractant to separate the HMF component. The mixture of the extractant benzene and the solute HMF enters the distillation tower III 27. The boiling point of benzene is lower than that of HMF. Therefore, benzene is first evaporated and then separated to obtain HMF, which enters the HMF purification tower 28. HMF is further purified until there are no other liquid impurities. Finally, it flows back to the HMF buffer tank 18 for storage and waits for the next round of reaction. The mixed liquid after HMF removal from the extraction separation tower 26 enters the distillation tower IV 29. Since the boiling point of MA is relatively high at about 275°C and the boiling point of HCOOH is relatively low at about 100.8°C, HCOOH is first evaporated and enters the HCOOH purification tower 30 for condensation and purification until there is no other impurity liquid, and finally flows into the HCOOH buffer tank 31 for storage to obtain the anode product I formic acid; The mixed liquid after removing HCOOH from distillation tower IV 29 enters distillation tower V 32. At this time, the main component in the liquid is MA. MA is evaporated and enters MA purification tower 33 for condensation and purification until there is no other impurity liquid. Finally, it flows into MA buffer tank 34 for storage to obtain anode product II maleic acid.

[0032] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0033] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A system for producing organic acids by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass, characterized in that: It includes a cathode module and an anode module. The cathode module comprises a first upstream raw material part, a first midstream electrolysis part and a first downstream product purification processing part, wherein: The first upstream raw material section includes: The exhaust tower treats carbon-containing industrial waste gas through desulfurization, denitrification and deoxygenation to discharge CO2 gas. A CO2 buffer tank connected to the waste gas tower to store the CO2 gas obtained after the treatment and recovery of carbon-containing industrial waste gas; The first midstream electrolysis section includes: The cathode electrolyte buffer tank stores the cathode electrolyte that has not participated in the reaction and is recovered. A cathode stirring tank is connected to the CO2 buffer tank and the cathode electrolyte buffer tank to stir and mix the CO2 and the cathode electrolyte evenly. A flow-type electrolytic cell connected to the cathode stirring tank and electrocatalytically reducing CO2 at the cathode; The first downstream product purification treatment section includes: Flash separator I, which is connected to the flow-type electrolytic cell to separate the gas-liquid products after the reaction to obtain a mixed liquid and a mixed gas, A CO2 capture tower is connected to the flash separator I to capture and separate CO2 from the mixed gas. The CO2 purification tower has one end connected to the CO2 capture tower and the other end connected to the CO2 buffer tank to purify and separate the CO2 to recover the CO2 gas. A pressure swing adsorption device is connected to the CO2 capture tower to separate CO from the mixed gas after CO2 separation. A CO purification tower is connected to a pressure swing adsorption device to purify the separated CO. The CO buffer tank is connected to the CO purification tower to store the separated CO product. a distillation column I connected to a flash separator I for distilling and separating the cathode electrolyte, a cathode electrolyte purification tower, one end of which is connected to the distillation tower I and the other end of which is connected to the cathode electrolyte buffer tank to purify the separated cathode electrolyte and recover it to the cathode electrolyte buffer tank; The anode module includes a second upstream raw material part, a second midstream electrolysis part and a second downstream product purification treatment part, wherein: The second upstream raw material part includes: A cellulose solution buffer tank is used to store and process the cellulose solution obtained from the waste biomass. Reactor I, which is connected to the cellulose solution buffer tank to hydrolyze cellulose into glucose solution, Reactor II, which is connected to reactor I, isomerizes the glucose in the glucose solution into fructose. Reactor III, which is connected to reactor II to dehydrate fructose into HMF; The HMF buffer tank is connected to the reactor III to store the HMF that has not participated in the reaction and is recovered. The second midstream electrolysis section includes: Anolyte buffer tank, which stores the anolyte that has not participated in the reaction and is recovered, An anode stirring tank, one end of which is connected to the HMF buffer tank and the anolyte buffer tank for stirring to evenly mix the HMF and the anolyte, and the other end of which is connected to the flow-type electrolytic cell for anodic oxidation of the HMF; The second downstream product purification treatment section includes: Flash separator II is connected to the flow-type electrolytic cell to separate the gas-liquid products after the reaction to obtain O2 and the second mixed liquid. The O2 purification tower is connected to the flash separator II to purify and separate the O2. The O2 buffer tank is connected to the O2 purification tower to store the separated O2. The distillation tower II is connected to the flash separator II to separate the anolyte and the mixed organic acid by distillation using the different boiling points of the second mixed liquid components. Anolyte purification tower, which is connected to distillation tower II and anolyte buffer tank to purify and separate the anolyte and recover it to the anolyte buffer tank, The extraction separation tower is connected to the distillation tower II, which uses benzene as an extractant to separate HMF and mixed organic acids. Distillation column III, which is connected to an extractive separation column to separate HMF, The HMF purification tower is connected to the distillation tower III and the HMF buffer tank, and the HMF after purification and separation is recovered to the HMF buffer tank. Distillation tower IV is connected to an extraction separation tower to separate formic acid HCOOH solution from the mixed organic acid. The HCOOH purification tower is connected to the distillation tower IV to purify and separate the HCOOH solution. The HCOOH buffer tank is connected to the HCOOH purification tower to store the separated HCOOH. Distillation tower V is connected to distillation tower IV to separate maleic acid MA solution from mixed organic acid. MA purification tower, which is connected to the distillation tower V to purify and separate the maleic acid MA solution, The MA buffer tank is connected to the MA purification tower to store the separated maleic acid MA solution.

2. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 1, characterized in that: Preferably, the exhaust tower is provided with an exhaust head for exhausting CO2 gas.

3. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 1, characterized in that: In reactor III, fructose is dehydrated to obtain 5-hydroxymethylfurfural HMF.

4. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 1, characterized in that: Waste biomass includes agricultural waste, waste cotton textiles and logging residues.

5. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 4, characterized in that: Agricultural waste includes straw.

6. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 1, characterized in that: The CO2 capture tower captures and separates CO2 from the mixed gas by using a physical adsorption method or a chemical absorption method.

7. The system for producing organic acid by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass as claimed in claim 1, characterized in that: The system is applicable to other electrode reactions and product combinations using CO2 and HMF as raw materials.

8. The method for treating a system for producing organic acids by electro-reduction of carbon-containing industrial waste gas coupled with oxidation of waste biomass according to any one of claims 1 to 7, characterized in that: It includes the following steps, Carbon-containing industrial waste gas is desulfurized, denitrified and deoxygenated in the waste gas tower and then discharged into the CO2 buffer tank through the exhaust header for storage; The CO2 gas stored in the CO2 buffer tank and the cathode electrolyte stored in the cathode electrolyte buffer tank that has not participated in the reaction enter the cathode stirring tank to be evenly mixed, and then enter the cathode chamber of the mobile electrolytic cell to participate in the reaction; The cellulose solution obtained by treating the waste biomass is stored in the cellulose solution buffer tank, and enters the reactor I to be hydrolyzed into glucose under the action of the catalyst. The glucose solution enters the reactor II to be isomerized into fructose under the action of the catalyst. The fructose solution enters the reactor III to be dehydrated under the action of the catalyst to obtain the HMF solution, and the HMF solution enters the HMF buffer tank for storage; The HMF solution stored in the HMF buffer tank and the anolyte that has not participated in the reaction stored in the anolyte buffer tank enter the anode stirring tank together for uniform mixing, and then enter the anode chamber of the mobile electrolytic cell to participate in the reaction; The mixed solution after the reaction in the cathode chamber of the flow-type electrolytic cell enters the flash separator I to separate the gas and liquid products; The mixed liquid obtained from the flash separator I enters the distillation tower I for liquid-liquid separation, and is distilled using boiling point difference to obtain a cathode electrolyte, which is then further purified in the cathode electrolyte purification tower to obtain a cathode electrolyte, and then flows back to the cathode electrolyte buffer tank for storage; The mixed gas obtained from the flash separator I enters the CO2 capture tower, where the CO2 gas is captured and separated from the mixed gas by physical adsorption or chemical absorption, and this part of the gas is continuously passed into the CO2 purification tower to purify and separate the CO2 until there are no other gas impurities, and finally passed back to the CO2 buffer tank for storage and waiting for the next round of reaction; The remaining mixed gas obtained after capturing and separating CO2 in the CO2 capture tower is passed into the pressure swing adsorption device, from which CO gas is separated and enters the CO purification tower, and the purified and separated CO is passed into the CO buffer tank for storage to obtain cathode product CO; The mixed solution after the reaction in the anode chamber of the flow-type electrolytic cell enters the flash separator II to separate the gas and liquid products; The mixed gas obtained from the flash separator II enters the O2 purification tower to separate and purify O2 until there are no other gas impurities, and finally enters the O2 buffer tank for storage to obtain the anode byproduct O2; The mixed solution obtained from the flash separator II enters the distillation tower II for liquid-liquid separation, and the anolyte containing impurities is obtained by distillation using the boiling point difference, and then enters the anolyte purification tower for further purification to obtain the anolyte without other impurities, and flows back to the anolyte buffer tank for storage; The remaining mixed liquid separated from distillation tower II enters the extraction separation tower, where benzene is used as an extractant to separate the HMF component. The mixture of the extractant benzene and the solute HMF enters the distillation tower III, where benzene is first evaporated and then separated to obtain HMF, which enters the HMF purification tower to further purify the HMF until there are no other liquid impurities. Finally, it flows back to the HMF buffer tank for storage and waits for the next round of reaction. The mixed liquid after HMF removal from the extraction separation tower enters the distillation tower IV, where HCOOH is first evaporated and then enters the HCOOH purification tower for condensation and purification until there is no other impurity liquid, and finally flows into the HCOOH buffer tank for storage to obtain formic acid; The mixed liquid after HCOOH removal obtained from distillation tower IV enters distillation tower V, MA is evaporated, enters MA purification tower, condenses and purifies until there is no other impurity liquid, and finally flows into MA buffer tank for storage to obtain maleic acid.

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