Device and novel process for producing fuel ethanol and electronic grade ethanol by rectification-membrane separation coupling method
阅读说明：本技术 一种精馏-膜分离耦合法生产燃料乙醇、电子级乙醇的装置及新工艺 (Device and novel process for producing fuel ethanol and electronic grade ethanol by rectification-membrane separation coupling method ) 是由 顾学红 罗虎 孙振江 洪周 李永恒 王圣贤 陈莽 许旺发 于 2019-11-20 设计创作，主要内容包括：本发明涉及乙醇生产领域,具体公开了一种精馏-膜分离耦合法生产燃料乙醇、电子级乙醇的装置及新工艺。该装置包括原料泵(1)、醪液预热器(2)、粗馏塔(3)、粗馏塔塔顶冷凝器(4)、粗馏塔塔底再沸器(5)、Ⅰ精馏塔(6)、Ⅰ精馏塔塔顶冷凝器(7)、Ⅰ精馏塔塔底再沸器(8)、闪蒸罐(9)、Ⅱ精馏塔(10)、Ⅱ精馏塔塔顶冷凝器(11)、Ⅱ精馏塔塔底再沸器(12)、蒸汽渗透膜分离装置(13)、冷凝罐(14)、去离子膜装置(15),能同时生产燃料乙醇和电子级乙醇两种产品,适应市场多元化的需求。此外,能有效利用装置的富余热能,实现能量充分地互相匹配利用,节约蒸汽消耗,与传统的工艺相比可节省蒸汽达20％以上。(The invention relates to the field of ethanol production, and particularly discloses a device and a novel process for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method. The device includes raw material pump (1), mash preheater (2), gas retort (3), gas retort top condenser (4), gas retort bottom reboiler (5), I rectifying column (6), I rectifying column top condenser (7), reboiler (8) at the bottom of I rectifying column, flash drum (9), II rectifying column (10), II rectifying column top condenser (11), reboiler (12) at the bottom of II rectifying column, vapor permeable membrane separator (13), condensing tank (14), deionization membrane device (15), can produce two kinds of products of fuel ethanol and electronic grade ethanol simultaneously, the demand of adaptation market pluralism. In addition, the surplus heat energy of the device can be effectively utilized, the energy is fully matched and utilized, the steam consumption is saved, and compared with the traditional process, the steam can be saved by more than 20%.)
1. The utility model provides a device of rectification-membrane separation coupling method production fuel ethanol, electronic grade ethanol, including raw material pump (1), mash preheater (2), rough distillation column (3), rough distillation column top condenser (4), rough distillation column bottom reboiler (5), I rectifying column (6), I rectifying column top condenser (7), I rectifying column bottom reboiler (8), flash tank (9), II rectifying column (10), II rectifying column top condenser (11), II rectifying column bottom reboiler (12), condensing tank (14), its characterized in that: also comprises a vapor permeable membrane separation device (13) and a deionization membrane device (15); the raw material pump (1), the mash preheater (2), the coarse distillation tower (3), the overhead condenser (4) of the coarse distillation tower and the bottom reboiler (5) of the coarse distillation tower are sequentially communicated through pipelines; the rectifying tower I (6), the rectifying tower top condenser I (7), the rectifying tower bottom reboiler I (8) and the flash tank I (9) are communicated in sequence through pipelines; the rectifying tower II (10), a rectifying tower top condenser (11) and a rectifying tower bottom reboiler (12) are communicated in sequence through pipelines; the vapor permeable membrane separation device (13), the condensing tank (14) and the deionization membrane device (15) are communicated in sequence through pipelines; the discharge hole of the mash preheater (2) is connected with the feed inlet pipeline of the coarse distillation tower (3); the discharge hole of the condenser (4) at the top of the rough distillation tower is connected with the feed hole of the rectifying tower (6) through a pipeline; the discharge hole of the flash tank (9) is connected with the feed hole of the rectifying tower (10) II through a pipeline; the discharge hole of the condenser (11) at the top of the rectifying tower II is connected with the feed hole pipeline of the vapor permeable membrane separation device (13); a fuel ethanol outlet is arranged on a lower pipeline of the condensation tank (14); the deionization membrane device (15) is provided with an electronic grade ethanol outlet.
2. The device for producing fuel ethanol and electronic grade ethanol by the rectification-membrane separation coupling method according to claim 1, wherein the device comprises: the deionization membrane device (15) comprises an ion exchange membrane or a nanofiltration membrane.
3. The device for producing fuel ethanol and electronic grade ethanol by the rectification-membrane separation coupling method according to claim 1, wherein the device comprises: the steam permeable membrane configuration of the steam permeable membrane separation device (13) comprises a plate type, a tubular type and a hollow fiber type.
4. The device for producing fuel ethanol and electronic grade ethanol by the rectification-membrane separation coupling method according to claim 3, wherein the device comprises: the vapor permeable membrane is an organic or inorganic membrane and comprises a PVA membrane, a NaA molecular sieve membrane, a T-shaped molecular sieve membrane, an MOR molecular sieve membrane and a ZSM-5 molecular sieve membrane.
5. A novel process for the production of fuel ethanol, electronic grade ethanol, using a production plant according to any of claims 1 to 4, characterized in that it comprises the following steps:
mature mash from a fermentation working section enters the coarse distillation tower (3) after being preheated, and coarse wine with the concentration of 40 ~ 60% (v/v) obtained at the top of the coarse distillation tower (3) enters the rectifying tower (6) I to remove water and fusel oil;
high-concentration alcohol with the concentration of 85 ~ 95% (v/v) obtained at the top of the rectifying tower I (6) enters the rectifying tower II (10) from the flash tank (9);
meanwhile, about half of mash in the coarse distillation tower (3) is extracted from the coarse distillation tower (3) and enters a rectifying tower II (10), and after the rectifying tower II (10) is further dehydrated, alcohol steam with the concentration of 85 ~ 97% (v/v) is obtained at the top of the tower;
the alcohol steam enters the steam permeable membrane separation device (13) for deep dehydration, high-purity ethanol steam with the concentration of 99.5 ~ 99.9.9% (v/v) is obtained by membrane residue measurement, feed liquid with the ethanol content of 1-5% (v/v) at the permeation side is conveyed to a mash pool for continuous circulation and recovery, and dehydrated ethanol steam is condensed to obtain a fuel ethanol product;
part of high-purity fuel ethanol products are subjected to ion removal membrane to remove trace ions, and then electronic grade ethanol products are obtained.
6. The novel process for producing fuel ethanol, electronic grade ethanol, according to claim 5, wherein: mature mash entering the coarse distillation tower (3) is preheated by tower kettle waste mash of the coarse distillation tower (3), tower bottom waste liquid of the rectifying tower I (6), tower bottom waste liquid of the rectifying tower II (10) and finished anhydrous ethanol of the vapor permeable membrane separation device (13).
7. The novel process for producing fuel ethanol, electronic grade ethanol, according to claim 5, wherein: the heat of the reboiler (5) at the bottom of the coarse distillation tower is from the reflux steam at the top of the rectifying tower (10) II, and the heat of the reboiler (12) at the bottom of the rectifying tower II is from the reflux steam at the top of the rectifying tower I (6).
8. The new process for producing fuel ethanol and electronic grade ethanol according to claim 5, wherein the operation pressure of the top of the crude distillation tower (3) is 0 ~ 0.12MPa (gauge pressure), the operation temperature of the top of the crude distillation tower (3) is 75 ~ 85 ℃, and the operation temperature of the bottom of the crude distillation tower (3) is 85 ~ 95 ℃.
9. The new process for producing fuel ethanol and electronic grade ethanol as claimed in claim 5, wherein the operating pressure at the top of the rectifying tower (6) is 0.2 ~ 0.35MPa (gauge pressure), the temperature at the top of the rectifying tower (6) is 108 ~ 120 ℃, and the temperature at the bottom of the rectifying tower (6) is 130 ~ 150 ℃.
10. The new process for producing fuel ethanol and electronic grade ethanol according to claim 5, wherein the operating pressure at the top of the rectifying tower II (10) is 0.12 ~ 0.2MPa (gauge pressure), the operating temperature at the top of the rectifying tower II (10) is 95 ~ 105 ℃, and the operating temperature at the bottom of the rectifying tower II (10) is 105 ~ 115 ℃.
Technical Field
The invention relates to the field of ethanol production, in particular to a device and a novel process for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method.
Background
With the continuous development of electronic technology, the cleaning problem of precise electronic components and chips is more and more concerned. The ultra-clean high-purity chemical reagent is mainly used for solving the problems, wherein electronic grade absolute ethyl alcohol is taken as one of ultra-clean high-purity chemicals and is widely applied to various fields of military industry, chemical industry, electronics, energy, machinery, environmental protection, medicine and the like at present. Because the electronic grade ethanol has high quality requirement, has strict requirement on production environment and cannot be widely produced. The common purification technologies include distillation, rectification, reduced pressure distillation, gas absorption and the like, and the purification technologies have characteristics of large equipment investment and high energy consumption, so that the purification technologies are not widely applied. Under the condition of increasingly scarce resources, a new process for producing electronic-grade ethanol with low energy consumption is urgently needed. Chinese patent CN102260140A proposes that gases near azeotropic composition at the top of a rectifying tower are all condensed into liquid, then the liquid is heated to 80-90 ℃ and then sent into an infiltration vaporization membrane component, which causes huge waste of energy consumption, and simultaneously, serious concentration polarization and temperature difference polarization phenomena are generated in the liquid infiltration vaporization process. Chinese patent CN206980234U proposes a filtering device for specific electronic grade ethanol, but the filtering effect is not obvious, and the filtering device cannot be widely applied to market demands. Chinese patent CN204310984U discloses a seven-tower multi-effect differential pressure distillation apparatus for co-producing superior alcohol and fuel ethanol, which can co-produce superior alcohol and fuel ethanol, but cannot produce electronic grade anhydrous ethanol at the same time.
Disclosure of Invention
In view of the above, the present invention is intended to provide a device and a new process for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, which can simultaneously produce two products, namely fuel ethanol and electronic grade absolute ethanol, in a set of device, and simultaneously adopt a rectification-steam permeation coupling mode, so as to effectively utilize surplus heat energy of the device, realize sufficient energy recycling, and achieve the purposes of reducing cost and being environment-friendly.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
the invention provides a device for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, which comprises a raw material pump, a mash preheater, a rough distillation tower, a top condenser of the rough distillation tower, a bottom reboiler of the rough distillation tower, a rectifying tower I, a top condenser of the rectifying tower I, a bottom reboiler of the rectifying tower I, a flash tank, a rectifying tower II, a top condenser of the rectifying tower II, a bottom reboiler of the rectifying tower II and a condensing tank, and is characterized in that: also comprises a vapor permeable membrane separation device and a deionization membrane device; the raw material pump, the mash preheater, the coarse distillation tower, the overhead condenser of the coarse distillation tower and the bottom reboiler of the coarse distillation tower are sequentially communicated through pipelines; the rectifying tower I, the rectifying tower top condenser I, the rectifying tower bottom reboiler I and the flash tank are sequentially communicated through pipelines; the rectifying tower II, a tower top condenser of the rectifying tower II and a reboiler at the tower bottom of the rectifying tower II are sequentially communicated through pipelines; the steam permeable membrane separation device, the condensing tank and the deionization membrane device are sequentially communicated through pipelines; the discharge hole of the mash preheater is connected with a feed inlet pipeline of the coarse distillation tower; the discharge port of the condenser at the top of the rough distillation tower is connected with the feed port pipeline of the rectifying tower I; the discharge hole of the flash tank is connected with the feed hole pipeline of the rectifying tower II; the discharge port of the condenser at the top of the rectifying tower II is connected with the feed port pipeline of the vapor permeable membrane separation device; a fuel ethanol outlet is formed in a lower pipeline of the condensation tank; the deionization membrane device is provided with an electronic grade ethanol outlet.
Further, the deionization membrane device comprises an ion exchange membrane or a nanofiltration membrane.
Further, the vapor permeable membrane configuration of the vapor permeable membrane separation device comprises a plate type, a tubular type and a hollow fiber type.
Furthermore, the vapor permeable membrane is an organic or inorganic membrane, and comprises a PVA membrane, a NaA molecular sieve membrane, a T-type molecular sieve membrane, an MOR molecular sieve membrane and a ZSM-5 molecular sieve membrane.
The invention also provides a new process for producing fuel ethanol and electronic grade ethanol, and the device for producing the fuel ethanol and the electronic grade ethanol by using the rectification-membrane separation coupling method comprises the following steps:
preheating mature mash from a fermentation working section, then feeding the preheated mature mash into the coarse distillation tower, feeding coarse wine with the concentration of 40 ~ 60% (v/v) obtained at the top of the coarse distillation tower into the rectifying tower I, and removing water and fusel oil;
high-concentration alcohol with the concentration of 85 ~ 95% (v/v) obtained at the top of the rectifying tower I enters the rectifying tower II from the flash tank;
meanwhile, about half of mash in the coarse distillation tower is extracted from the coarse distillation tower and enters a rectifying tower II, and after the rectifying tower II is further dehydrated, alcohol steam with the concentration of 85 ~ 97% (v/v) is obtained at the tower top;
the alcohol steam enters the steam permeable membrane separation device for deep dehydration, high-purity ethanol steam with the concentration of 99.5 ~ 99.9.9% (v/v) is obtained by membrane residue measurement, feed liquid with the ethanol content of 1-5% (v/v) at the permeation side is conveyed to a mash pool for continuous circulation and recovery, and dehydrated ethanol steam is condensed to obtain a fuel ethanol product;
part of high-purity fuel ethanol products are subjected to ion removal membrane to remove trace ions, and then electronic grade ethanol products are obtained.
Further, mature mash entering the rough distillation tower is preheated by tower kettle waste mash of the rough distillation tower, tower bottom waste liquid of the rectifying tower I and the rectifying tower II and finished absolute ethyl alcohol of the vapor permeable membrane separation device.
Furthermore, the heat of the reboiler at the bottom of the coarse distillation tower is derived from the reflux steam at the top of the rectifying tower II, and the heat of the reboiler at the bottom of the rectifying tower II is derived from the reflux steam at the top of the rectifying tower I.
Further, the operation pressure at the top of the crude distillation column was 0 ~ 0.12.12 MPa (gauge pressure), the operation temperature at the top of the crude distillation column was 75 ~ 85 ℃ and the operation temperature at the bottom of the crude distillation column was 85 ~ 95 ℃ respectively.
Further, the operation pressure of the top of the rectifying tower I is 0.2 ~ 0.35.35 MPa (gauge pressure), the temperature of the top of the rectifying tower I is 108 ~ 120 ℃, and the temperature of the bottom of the rectifying tower I is 130 ~ 150 ℃.
The operating pressure of the top of the II rectifying tower is 0.12 ~ 0.2.2 MPa (gauge pressure), the operating temperature of the top of the II rectifying tower is 95 ~ 105 ℃, and the operating temperature of the bottom of the II rectifying tower is 105 ~ 115 ℃.
The invention has the following beneficial effects:
1) the invention provides a device for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, which is coupled by a rectification-membrane separation technology, can simultaneously produce two products of the fuel ethanol and the electronic grade ethanol in a set of process devices, realizes the flexible adjustment of product productivity between the fuel ethanol and the electronic grade ethanol, and meets the diversified demands of the market;
2) the invention provides a new process for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, which uses a rectification-membrane separation coupling energy-saving process, can effectively utilize surplus heat energy of a device, realizes the sufficient mutual matching and utilization of energy, saves steam consumption, and has the steam unit consumption of the whole system of 1.1-1.4 tons of steam per ton of fuel ethanol product, thereby achieving the purpose of saving energy of the system, and can save the steam by more than 20 percent compared with the traditional process;
3) the invention provides a new process for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, and the whole process flow has the advantages of energy conservation, high efficiency, small occupied area, zero pollution, simple operation, high resource utilization rate and the like, and has huge market application prospect.
Drawings
FIG. 1 is a process flow chart of the distillation-membrane separation coupling method for producing fuel ethanol and electronic grade ethanol according to the embodiment of the invention
Wherein: 1 is a raw material pump; 2 is a mash preheater; 3 is a crude distillation column; 4 is a condensing tank at the top of the crude distillation tower; 5 is a reboiler at the bottom of the crude distillation tower; 6 is a rectifying tower I; 7 is a rectifying tower top condenser I; 8 is a reboiler at the bottom of the rectifying tower I; 9 is a flash tank; 10 is II rectifying tower; 11 is a tower top condenser of the rectifying tower II; 12 is a reboiler at the bottom of the rectifying tower II; 13 is a vapor permeable membrane separation device; 14 is a condensing tank; and 15 is a deionizing membrane unit.
Detailed Description
So that the manner in which the features and aspects of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings.
The core of the specific implementation mode of the invention is to provide a device for producing fuel ethanol and electronic grade ethanol by a rectification-membrane separation coupling method, which comprises a
Here, the
Specifically, the operating pressure of the nanofiltration membrane is 0.1-1 MPa (gauge pressure).
Specifically, the pore diameter of the nanofiltration membrane is 5 nm.
Here, the vapor permeable membrane configuration of the vapor permeable
Preferably, the vapor permeable membrane is an organic or inorganic membrane, and comprises a PVA membrane, a NaA molecular sieve membrane, a T-type molecular sieve membrane, an MOR molecular sieve membrane and a ZSM-5 molecular sieve membrane.
Specifically, the plate, tube, hollow fiber vapor permeable membrane configurations may be composed in one or both of series and parallel connections.
More specifically, the vapor permeable
More specifically, the vapor permeable
More specifically, the vapor permeable
The specific implementation mode of the invention also provides a novel process for producing fuel ethanol and electronic grade ethanol by using the production device, which is characterized by comprising the following steps:
preheating mature mash from a fermentation working section, then feeding the preheated mature mash into the
high-concentration alcohol with the concentration of 85 ~ 95% (v/v) obtained at the top of the rectifying tower I6 enters the rectifying tower II 10 from the
meanwhile, about half of mash in the
the alcohol steam enters the steam permeable
part of high-purity fuel ethanol products are subjected to ion removal membrane to remove trace ions, and then electronic grade ethanol products are obtained.
Here, the mash preheating temperature is 75-80 ℃.
The heat is recycled by adopting differential pressure coupling circulation heat supply, and simultaneously the waste water at the bottom of the rectifying tower and the ethanol steam obtained by membrane dehydration are recycled before being discharged out of the system.
Specifically, the mature mash entering the
Here, the heat of the reboiler 5 at the bottom of the crude distillation tower is derived from the reflux steam at the top of the rectifying
Here, the dehydration process can overcome the limitation of gas-liquid equilibrium without introducing a third component, and simultaneously can avoid the defect of complicated process flow of the traditional process.
The relative volatility of the ethanol and the water is high, so that the separation efficiency of the ethanol and the water in the rectifying tower is improved; the steam output from the top of the rectifying tower directly enters the steam permeable
Here, the ethanol feed liquid entering the vapor permeable
Here, the top vapor of the rectifying column II 10 serves as the heating medium for the rectifying column II 3, and the top vapor of the rectifying column I6 serves as the heating medium for the rectifying column II 10.
Here, the operation pressure at the top of the
Here, the operating pressure at the top of said I rectifying column 6 was 0.2 ~ 0.35.35 MPa (gauge pressure), the temperature at the top of said I rectifying column 6 was 108 ~ 120 ℃ and the temperature at the bottom of said I rectifying column 6 was 130 ~ 150 ℃ C.
Here, the operating pressure at the top of the
The single anion of the electronic grade absolute ethyl alcohol after the ion removal of the deionization membrane device is controlled below 1ppm, and the cation is controlled below 10 ppb.
Here, the high purity fuel ethanol product has a water content of < 0.1%.