CN112574826A - Device and method for preparing fatty acid methyl ester by continuous ester exchange - Google Patents
Device and method for preparing fatty acid methyl ester by continuous ester exchange Download PDFInfo
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- 235000019387 fatty acid methyl ester Nutrition 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 39
- 150000002148 esters Chemical group 0.000 title claims abstract 11
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 114
- 238000006243 chemical reaction Methods 0.000 claims abstract description 99
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims abstract description 63
- 239000007788 liquid Substances 0.000 claims abstract description 42
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims abstract description 23
- 239000002699 waste material Substances 0.000 claims abstract description 18
- 238000001704 evaporation Methods 0.000 claims abstract description 17
- 230000008020 evaporation Effects 0.000 claims abstract description 17
- 239000000463 material Substances 0.000 claims abstract description 17
- 238000005886 esterification reaction Methods 0.000 claims abstract description 8
- 238000002156 mixing Methods 0.000 claims description 47
- 125000005456 glyceride group Chemical group 0.000 claims description 43
- 238000000926 separation method Methods 0.000 claims description 38
- 239000000047 product Substances 0.000 claims description 33
- 235000011187 glycerol Nutrition 0.000 claims description 22
- 239000003513 alkali Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 15
- 150000008028 secondary esters Chemical group 0.000 claims description 11
- 150000004702 methyl esters Chemical class 0.000 claims description 8
- 150000005374 primary esters Chemical group 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 7
- 238000005086 pumping Methods 0.000 claims description 7
- 238000005070 sampling Methods 0.000 claims description 7
- 238000005809 transesterification reaction Methods 0.000 claims description 7
- 230000032050 esterification Effects 0.000 claims description 6
- 238000004062 sedimentation Methods 0.000 claims description 6
- 239000012295 chemical reaction liquid Substances 0.000 claims description 5
- CASUWPDYGGAUQV-UHFFFAOYSA-M potassium;methanol;hydroxide Chemical compound [OH-].[K+].OC CASUWPDYGGAUQV-UHFFFAOYSA-M 0.000 claims description 5
- 239000003054 catalyst Substances 0.000 claims description 4
- 238000007670 refining Methods 0.000 claims description 4
- 239000006227 byproduct Substances 0.000 claims description 3
- 238000004587 chromatography analysis Methods 0.000 claims description 3
- 238000004821 distillation Methods 0.000 claims description 3
- 235000013311 vegetables Nutrition 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 10
- 239000002994 raw material Substances 0.000 abstract description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 abstract description 4
- 239000010775 animal oil Substances 0.000 abstract 1
- 239000003921 oil Substances 0.000 abstract 1
- 235000019198 oils Nutrition 0.000 abstract 1
- 235000015112 vegetable and seed oil Nutrition 0.000 abstract 1
- 239000008158 vegetable oil Substances 0.000 abstract 1
- 125000004185 ester group Chemical group 0.000 description 38
- LDVVTQMJQSCDMK-UHFFFAOYSA-N 1,3-dihydroxypropan-2-yl formate Chemical compound OCC(CO)OC=O LDVVTQMJQSCDMK-UHFFFAOYSA-N 0.000 description 15
- 239000012530 fluid Substances 0.000 description 4
- 230000036632 reaction speed Effects 0.000 description 4
- 230000035484 reaction time Effects 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 239000003225 biodiesel Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000002028 Biomass Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- OGBUMNBNEWYMNJ-UHFFFAOYSA-N batilol Chemical class CCCCCCCCCCCCCCCCCCOCC(O)CO OGBUMNBNEWYMNJ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000005292 vacuum distillation Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11C—FATTY ACIDS FROM FATS, OILS OR WAXES; CANDLES; FATS, OILS OR FATTY ACIDS BY CHEMICAL MODIFICATION OF FATS, OILS, OR FATTY ACIDS OBTAINED THEREFROM
- C11C3/00—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom
- C11C3/04—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom by esterification of fats or fatty oils
- C11C3/10—Ester interchange
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- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
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Abstract
The invention provides a device and a method for preparing fatty acid methyl ester by continuous ester exchange, which take esterified liquid or animal and vegetable oil after the esterification reaction of waste oil and alcohol as raw material, mix with methanol solution of potassium hydroxide according to proportion, carry out two-stage ester exchange reaction in a continuous ester exchange device, then carry out flash evaporation to remove alcohol, remove glycerol from the material liquid after removing alcohol by standing, settling and separating to obtain crude fatty acid methyl ester, and the crude fatty acid methyl ester is rectified and refined to obtain the finished product of fatty acid methyl ester. The invention adopts two-stage ester exchange reaction, has the characteristics of reasonable process, thorough reaction and high product conversion rate, can ensure stable and qualified product quality, and meets the requirement of industrialized production.
Description
Technical Field
The invention relates to the technical field of production equipment and process methods of biomass energy, in particular to a device and a method for preparing fatty acid methyl ester by continuous ester exchange.
Background
Fatty acid methyl ester (commonly called as biodiesel) is a renewable green clean energy source capable of replacing petroleum diesel, is also an important biochemical basic raw material, and has the potential of large-scale industrialization, at present, in the production process of fatty acid methyl ester, ester exchange reaction of glyceride and methanol mostly uses a conventional stirring reaction device, and a one-step ester exchange method is adopted to prepare the fatty acid methyl ester, the conventional stirring reaction device is difficult to solve the problems of small contact area and slow reaction speed between oil-water two-phase molecules in the production process, higher temperature condition and longer reaction time are needed, and high temperature and longer reaction time further cause energy consumption aggravation and unstable product quality; the one-step ester exchange method production process is easy to cause incomplete reaction of glyceride, the product conversion rate is low, and the monoglyceride contained in the product is difficult to separate and remove through rectification because the molecular weight is close to that of the fatty acid methyl ester, so that the content of the monoglyceride in the produced fatty acid methyl ester product exceeds the standard and cannot meet the index requirement of the national standard (GB/T20828-2015) (the new international standard GB/T20828-2015 is added with the detection requirement of monoglyceride index compared with the old international standard GB/T20828 2014).
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a device and a method for preparing fatty acid methyl ester by continuous ester exchange, which solve the technical problems.
The technical scheme adopted by the invention for solving the technical problems is as follows:
firstly, providing a device for preparing fatty acid methyl ester by continuous ester exchange, which comprises a first tower type superfine contact reactor, a second tower type superfine contact reactor, a first ultramicro mixing reactor, a second ultramicro mixing reactor, a batching tank, a first settling separation tank, a second settling separation tank, a flash evaporation kettle and a waste methanol collecting tank; the batching tank is connected with a first delivery pump, a first ultramicro mixing reactor, a first heat exchanger and the top of a first tower type superfine contact reactor through pipelines, two pipelines are arranged at the bottom of the first tower type reactor, one pipeline is connected with the first delivery pump, the other pipeline is connected with a second delivery pump and the top of a first sedimentation separation tank, the first sedimentation separation tank is provided with a bottom pipeline and a side pipeline, the side pipeline is connected with a third delivery pump, an alcohol-alkali solution tank, a second ultramicro mixing reactor, a second heat exchanger and the top of the second tower type superfine contact reactor, the bottom pipeline is connected with a fourth delivery pump, a third heat exchanger and the side of a flash evaporation kettle, two pipelines are arranged at the bottom of the second tower type superfine contact reactor, one pipeline is connected with the third delivery pump, the other pipeline is connected with the fourth delivery pump, the top of the flash still is connected with the fourth heat exchanger and the waste methanol collection tank through pipelines, the waste methanol collection tank is connected with the methanol distillation system through a seventh delivery pump, the bottom of the flash still is connected with the top of a fifth delivery pump and the top of a second settling separation tank through pipelines, and the second settling separation tank is respectively connected with the methyl ester rectification system and the glycerol rectification system.
An ultramicro mixing reactor in a device for preparing fatty acid methyl ester by continuous ester exchange is static tubular instantaneous mixing equipment, no moving part is arranged in the ultramicro mixing reactor, and the ultramicro mixing reactor mainly utilizes fluid flow to generate thinning shunting, cross mixing and reverse rotational flow in an internal unit, increases the speed gradient of laminar flow movement of fluid, enables the fluid to be divided and uniformly mixed, and realizes the rapid and efficient mixing of various fluid materials; the tower type superfine contact reactor is composed of an upper part and a lower part, the top end of an upper part unit is provided with a cavitation strengthening distributor with a hole plate, the inside of the upper part unit is provided with a filler, the contact area and the contact time of heterogeneous materials can be improved, the lower part unit is a cylindrical device which is sleeved inside and outside and forms an inner reaction chamber and an outer reaction chamber of the reactor, the top of the inner reaction chamber is provided with the distributor, the inner reaction chamber and the outer reaction chamber are both provided with microporous groove type baffles at the bottoms, the reaction materials can be fully mixed, the reaction speed is increased, the inner reaction chamber and the outer reaction chamber of the upper part unit and the lower part unit are equivalent to three ester exchange reaction devices which are connected in series; the middle part of the settling separation tank is provided with an overflow port, so that the separation effect of fatty acid methyl ester and glycerol can be better.
The invention also provides a method for preparing fatty acid methyl ester by continuous ester exchange, which comprises the following steps:
s1: mixing glyceride and methanol according to a mass ratio of 5: 1, adding a potassium hydroxide catalyst which is 0.6 percent of the total amount of the reaction liquid, stirring and mixing uniformly, feeding the mixture into a first ultra-micro mixing reactor through a first conveying pump, heating the mixture to 60 ℃ through a first heat exchanger, feeding the mixture into a first tower type ultra-fine contact reactor for primary ester exchange reaction, closing a valve at the bottom of a batching tank to stop feeding when the material reaches the capacity of 3/4 of the first tower type ultra-fine contact reactor, and sampling and detecting the ester exchange reaction process;
s2: when the first-stage esterification exchange is finished, the conversion rate of the glyceride is required to be more than or equal to 85 percent, if the reaction does not reach the standard, a valve at the bottom of the first tower type superfine contact reactor is opened, the feed liquid enters the first superfine mixing reactor through the first conveying pump again, the temperature of the feed liquid is raised through the first heat exchanger, the feed liquid enters the top of the first tower type superfine contact reactor for further circulation reaction, if the temperature is not enough in the circulation process, the temperature of the feed liquid can be raised through the first heat exchanger, the reaction temperature is kept at 58-62 ℃, and when the conversion rate of the glyceride is more than or equal to 85 percent, the second conveying pump is opened to pump the first-stage ester exchange liquid into the first settling separation tank for settling for 1-2 hours, and then the lower;
s3: pumping the first-stage ester exchange liquid without the glycerol in the first settling separation tank into a second ultramicro mixing reactor by using a third delivery pump, and simultaneously mixing a potassium hydroxide methanol solution in an alcohol-alkali solution tank with the first-stage ester exchange liquid according to the instantaneous flow rate of 1: 10, heating the mixture to 60 ℃ through a second heat exchanger, entering a second tower type superfine contact reactor for secondary ester exchange reaction, closing a third delivery pump and an eighth delivery pump at the bottom of an alcohol-alkali solution tank to stop feeding when the material reaches the capacity of the second tower type superfine contact reactor of 3/4, and sampling and detecting the ester exchange reaction process;
s4: the conversion rate of the glyceride is required to be more than or equal to 98% after the secondary ester exchange is finished, if the reaction does not reach the standard, a tower bottom valve of the second tower type superfine contact reactor is opened, the feed liquid enters the second superfine mixing reactor through the third transfer pump again, the temperature of the feed liquid is raised through the second heat exchanger and then enters the top of the second tower type superfine contact reactor for further circulating reaction, if the temperature is insufficient in the circulating process, the temperature of the feed liquid can be raised through the second heat exchanger, the reaction temperature is kept at 58-62 ℃, when the conversion rate of the glyceride is more than or equal to 98%, a fourth transfer pump is opened to pump the secondary ester exchange liquid into a flash evaporation kettle through the third heat exchanger, and the methanol which is flashed off enters a waste methanol collection tank through the fourth heat exchanger and then enters a methanol rectification system; and (3) pumping the material liquid after flash evaporation into a second settling separation tank by using a fifth delivery pump, standing and settling for 4-5 hours, allowing waste glycerin at the bottom to enter a glycerin rectification system by using a sixth delivery pump, allowing a crude fatty acid methyl ester product obtained by overflowing from an overflow port in the middle of the second settling separation tank to enter a methyl ester rectification system, and rectifying and refining to obtain a fatty acid methyl ester finished product and a byproduct vegetable pitch.
Further, the glyceride conversion was calculated using chromatography.
Further, the concentration of the methanolic potassium hydroxide solution in the alcohol-alkali solution tank of step S3 is 3%.
Compared with the prior art, the invention has the following beneficial effects:
1. the contact area and the contact time of heterogeneous glyceride (hydrophobic phase) and methanol (hydrophilic phase) and the reaction speed are improved.
2. The two-stage ester exchange reaction can better solve the problems that the glyceride reaction is not thorough, the product conversion rate is low and the content of the monoglyceride in the produced fatty acid methyl ester product exceeds the standard due to the one-step ester exchange method production process.
3. The conversion rate of the glyceride is calculated according to the ratio of the actual consumption amount of the methanol to the theoretically calculated consumption amount of the methanol in the reaction process, and the conversion rate has higher practical value for mastering the reaction process.
4. The method has the advantages of reasonable process, advanced equipment, high reaction speed, high product conversion rate and low production cost, can ensure stable and qualified product quality, meets the technical requirements of industrialization, and has higher popularization and application values.
Drawings
FIG. 1 is a schematic view of the overall structure of the present invention;
wherein, 1-a first tower type superfine contact reactor, 2-a second tower type superfine contact reactor, 3-a first superfine mixing reactor, 4-a second superfine mixing reactor, 5-a batching tank, 6-a first settling separation tank, 7-a second settling separation tank, 8-a flash evaporation kettle, 9-a waste methanol collection tank, 10-a first delivery pump, 11-a first heat exchanger, 12-a second delivery pump, 13-a third delivery pump, 14-a second heat exchanger, 15-a fourth delivery pump, 16-a third heat exchanger, 17-a fourth heat exchanger, 18-a fifth delivery pump, 19-a sixth delivery pump, 20-a seventh delivery pump, 21-an alcohol alkali solution tank, 22-a methanol rectification system and 23-a methyl ester rectification system, 24-glycerol rectification system.
Detailed Description
The following description of the embodiments of the present invention refers to the accompanying drawings and examples:
it should be noted that the structures, proportions, sizes, and other dimensions shown in the drawings and described in the specification are only for the purpose of understanding and reading the present disclosure, and are not intended to limit the scope of the present disclosure, which is defined by the following claims, and any modifications of the structures, changes in the proportions and adjustments of the sizes, without affecting the efficacy and attainment of the same, are intended to fall within the scope of the present disclosure.
In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention.
Referring to fig. 1, fig. 1 illustrates the overall structure of the present invention, and a device for preparing fatty acid methyl ester by continuous transesterification includes a first tower type ultrafine contact reactor 1, a second tower type ultrafine contact reactor 2, a first ultra-micro mixing reactor 3, a second ultra-micro mixing reactor 4, a dosing tank 5, a first settling separation tank 6, a second settling separation tank 7, a flash evaporation kettle 8 and a waste methanol collection tank 9; the batching tank 5 is connected with a first conveying pump 10, a first ultra-micro mixing reactor 3, a first heat exchanger 11 and the top of a first tower type ultra-fine contact reactor 1 through pipelines, two pipelines are arranged at the bottom of the first tower type reactor 1, one pipeline is connected with the first conveying pump 10, the other pipeline is connected with a second conveying pump 12 and the top of a first sedimentation separation tank 6, the first sedimentation separation tank 6 is provided with a bottom pipeline and a side pipeline, the side pipeline is connected with a third conveying pump 13, an alcohol-alkali solution tank 21, a second ultra-fine mixing reactor 4, a second heat exchanger 14 and the top of a second tower type ultra-fine contact reactor 2, the bottom pipeline is connected with a fourth conveying pump 15, a third heat exchanger 16 and the side of a flash evaporation kettle 8, the bottom of the second tower type ultra-fine contact reactor 2 is provided with a pipeline, and the other pipeline is connected with the third conveying pump 13, another pipeline is connected with fourth delivery pump 15, the top of flash kettle 8 is passed through the pipeline and is connected with fourth heat exchanger 17 and useless methanol collection tank 9, useless methanol collection tank 9 is connected with methanol distillation system 22 through seventh delivery pump 20, 8 bottoms of flash kettle are passed through the pipeline and are connected with fifth delivery pump 18 and second settling separation jar 7 tops, second settling separation jar 7 is connected with methyl ester rectification system 23 and glycerine rectification system 24 respectively.
A method for preparing fatty acid methyl ester by continuous ester exchange comprises the following steps:
s1: mixing glyceride and methanol according to a mass ratio of 5: 1, pumping the mixture into a proportioning tank 5, adding a potassium hydroxide catalyst which is 0.6 percent of the total amount of the reaction liquid, stirring and mixing the mixture uniformly, entering a first ultra-micro mixing reactor 3 through a first conveying pump 10, heating the mixture to 60 ℃ through a first heat exchanger 11, entering a first tower type ultra-fine contact reactor 1 for primary ester exchange reaction, closing a valve 25 at the bottom of the proportioning tank 5 to stop feeding when the material reaches the capacity 3/4 of the first tower type ultra-fine contact reactor 1, and sampling and detecting the ester exchange reaction process;
s2: when the first-stage esterification exchange is finished, the conversion rate of the glyceride is required to be more than or equal to 85 percent, if the reaction does not reach the standard, a valve 25 at the bottom of the first tower type superfine contact reactor 1 is opened, the feed liquid enters the first superfine mixing reactor 3 through the first conveying pump 10 again, the temperature of the feed liquid is raised through the first heat exchanger 11 and then enters the top of the first tower type superfine contact reactor 1 for further circulating reaction, if the temperature is not enough in the circulating process, the temperature of the feed liquid can be raised through the first heat exchanger 11, the reaction temperature is kept at 58-62 ℃, and when the conversion rate of the glyceride is more than or equal to 85 percent, the second conveying pump 12 is opened, the first-stage ester exchange liquid is injected into the first settling separation tank 6 for settling for 1-2 hours, and then the lower;
s3: and pumping the first-stage ester exchange liquid without the glycerol in the first settling separation tank 6 into a second ultra-micro mixing reactor 4 by using a third delivery pump 13, and simultaneously mixing a potassium hydroxide methanol solution in an alcohol-alkali solution tank 21 and the first-stage ester exchange liquid according to the instantaneous flow rate of 1: 10, then the mixture is heated to 60 ℃ by a second heat exchanger 14 and enters a second tower type superfine contact reactor 2 for secondary ester exchange reaction, when the volume of the material reaches 3/4 of the second tower type superfine contact reactor 2, a third delivery pump 13 and an eighth delivery pump at the bottom of an alcohol-alkali solution tank 21 are closed to stop feeding, and the ester exchange reaction process is sampled and detected;
s4: the conversion rate of the glyceride is required to be more than or equal to 98% after the secondary ester exchange is finished, if the reaction does not reach the standard, a tower bottom valve 25 of the second tower type superfine contact reactor 2 is opened, the feed liquid enters the second superfine mixing reactor 4 through the third transfer pump 13 again, the temperature of the feed liquid is raised through the second heat exchanger 14 and then enters the top of the second tower type superfine contact reactor 2 for further circulating reaction, if the temperature is not enough in the circulating process, the temperature of the feed liquid can be raised through the second heat exchanger 14, the reaction temperature is kept at 58-62 ℃, when the conversion rate of the glyceride is more than or equal to 98%, the fourth transfer pump 15 is opened to pump the secondary ester exchange liquid into a flash evaporation kettle 8 through the third heat exchanger 16, and the methanol which is flash evaporated enters a waste methanol collection tank 9 through the fourth heat exchanger 17 and then enters a methanol rectification system 22; and (3) pumping the material liquid after flash evaporation into a second settling separation tank 7 by using a fifth delivery pump 18, standing and settling for 4-5 hours, allowing waste glycerin at the bottom to enter a glycerin rectification system 24 through a sixth delivery pump 19, allowing a crude fatty acid methyl ester product obtained by overflowing from an overflow port in the middle of the second settling separation tank 7 to enter a methyl ester rectification system 23, and rectifying and refining to obtain a fatty acid methyl ester finished product and a byproduct vegetable pitch.
Specifically, the glyceride conversion was calculated using chromatography.
Specifically, the concentration of the methanolic potassium hydroxide solution in the alcohol-alkali solution tank of step S3 is 3%.
In the embodiment, the raw materials are esterification liquid (fatty acid in waste oil and fat is subjected to esterification reaction with glycerol, the glycerol is removed under the vacuum condition after the reaction is finished, and the main component is glyceride) after the glycerol esterification in the production process of a company, the acid value of the esterification liquid is detected to be 0.5mg KOH/g, the method for preparing fatty acid methyl ester by continuous ester exchange and the method for preparing fatty acid methyl ester by one-step ester exchange in the prior art are respectively adopted in the specific implementation process to carry out a comparative experiment, and the relevant operation flow, steps and relevant parameters are as follows:
example A method of the present invention for preparing fatty acid methyl ester by continuous transesterification is described as an example
(1) Mixing glyceride and methanol according to a mass ratio of 5: 1, adding the mixture into a proportioning tank 5, adding a potassium hydroxide catalyst accounting for 0.6 percent of the total amount of the reaction liquid, stirring and mixing uniformly, entering a first ultra-micro mixing reactor 3 through a first conveying pump 10, heating to 60 ℃ through a first heat exchanger 11, entering the first tower type ultra-fine contact reactor 1 for primary ester exchange reaction, closing a valve 25 at the bottom of the proportioning tank 5 to stop feeding when the material reaches the capacity 3/4 of the first tower type ultra-fine contact reactor 1, sampling to detect that the conversion rate of the glyceride is 89 percent (meeting the index requirement that the conversion rate of the glyceride is more than or equal to 85 percent after the primary ester exchange is finished), opening a second conveying pump 12 to pump the primary ester exchange liquid into a first settling separation tank 6 for settling for 1-2 hours, and then separating and removing the lower glycerol;
(2) and pumping the first-stage ester exchange liquid without the glycerol in the first settling separation tank 6 into a second ultra-micro mixing reactor 4 by using a third delivery pump 13, and simultaneously mixing a potassium hydroxide methanol solution in an alcohol-alkali solution tank 21 and the first-stage ester exchange liquid according to the instantaneous flow rate of 1: 10, then the mixture is fed into the second ultra-micro mixing reactor 4, the mixture is heated to 60 ℃ by a second heat exchanger 14 and then enters a second tower type ultra-fine contact reactor 2 for secondary ester exchange reaction, when the material reaches the capacity 3/4 of the second tower type ultra-fine contact reactor 2, a third delivery pump 13 and an eighth delivery pump at the bottom of an alcohol-alkali solution tank 21 are closed to stop feeding, the conversion rate of the glyceride is detected to be 98.7% by sampling (the conversion rate of the glyceride is equal to or more than 98% after the secondary ester exchange), a fourth delivery pump 15 is opened to feed secondary ester exchange liquid into a flash evaporation kettle 8 through a third heat exchanger 16, and the methanol which is flashed off is fed into a waste methanol collection tank 9 through a fourth heat exchanger 17 and then enters a methanol rectification system 22; and (3) feeding the material liquid after flash evaporation into a second settling separation tank 7 by using a fifth delivery pump 18, standing and settling for 4-5 hours, feeding the waste glycerol at the bottom into a glycerol rectification system 24 by using a sixth delivery pump 19, feeding a crude fatty acid methyl ester product obtained by overflowing from an overflow port in the middle of the second settling separation tank 7 into a methyl ester rectification system 23, and rectifying and refining to obtain a fatty acid methyl ester finished product (commonly called biodiesel), wherein the monoglyceride content of the product is 0.30% according to the detection of an SH/T0796 standard method, and the product meets the index requirement that the monoglyceride content is not more than 0.80% in a new national standard (GB/T20828-.
The commonly used method for preparing fatty acid methyl ester by one-step ester exchange is taken as a comparative example
(1) Taking 3 numbers (No. 1, No. 2 and No. 3) of a 500ml four-neck flask, adding 201.70 g, 200.30 g and 198.80 g of glyceride raw materials respectively, adding 30% methanol and 1% potassium hydroxide of the glyceride raw materials respectively, stirring, heating to 60 ℃, timing and carrying out transesterification reaction;
(2) in the ester exchange reaction process, the reaction liquid in the flasks 1, 2 and 3 is controlled at 58-62 ℃, and the reaction completion time is set as follows: number 1 for 30 minutes; number 2 for 60 minutes; number 3 for 90 minutes;
(3) after the three samples are reacted, removing methanol under vacuum condition, respectively filling the material liquid after removing methanol into corresponding No. 1, No. 2 and No. 3 separating funnels, standing and settling for 4-5 hours, separating and removing the glycerol at the bottom to obtain crude fatty acid methyl ester, and carrying out vacuum distillation to obtain a fatty acid methyl ester product;
(4) the conversion of glycerides and the monoglyceride content data of the products, determined after completion of the transesterification reactions No. 1, No. 2 and No. 3, are shown in Table 1 below.
| Sample numbering | Reaction temperature | Reaction time | Conversion rate of glycerides | The monoglyceride content of the |
| 1 | 60℃ | 30 minutes | 92.7％ | 1.07％ |
| 2 | 60℃ | 60 minutes | 96.5％ | 0.96％ |
| 3 | 60℃ | 90 minutes | 95.8％ | 0.98％ |
TABLE 1
From the data of conversion of glycerides and the content of monoglycerides of the product in the table, the following analytical conclusions can be drawn:
the conversion rate of glyceride is lowest when the ester exchange reaction is carried out for 30 minutes (No. 1), which indicates that the reaction is not completed; the highest conversion of glyceride was achieved at 60 minutes (No. 2), indicating that the reaction was substantially complete; the glyceride conversion at 90 minutes (No. 3) fell slightly back from the glyceride conversion at 60 minutes (No. 2), indicating that the reaction was complete and the reverse of the transesterification reaction was initiated;
the highest content of monoglyceride of the product No. 1 indicates that the glyceride conversion reaction is not finished in 30 minutes; the lowest monoglyceride content of the product No. 2 indicates that the glyceride conversion reaction is basically finished in 60 minutes; the monoglyceride content of the product No. 3 is slightly higher than that of the product No. 2, which indicates that the glyceride conversion reaction is finished and the reverse reaction of the glyceride conversion reaction is started;
③ the products No. 1, No. 2 and No. 3 have the monoglyceride content of more than 0.80 percent, and do not meet the index requirement that the monoglyceride content in the new national standard (GB/T20828-2015) is not more than 0.80 percent;
to sum up, the analysis of the first, second and third strips shows that the reaction time is preferably 60 minutes when the fatty acid methyl ester is prepared by adopting the one-step ester exchange method, but the monoglyceride content of the product does not meet the standard requirement in the new national standard (GB/T20828-2015).
Conclusion
According to the embodiment, compared with the related process flow, parameters and product indexes in the comparison experiment of the method for preparing fatty acid methyl ester by continuous ester exchange and the method for preparing fatty acid methyl ester by one-step ester exchange commonly used at present, the method for preparing fatty acid methyl ester by continuous ester exchange improves the defects of the conventional method for preparing fatty acid methyl ester by stirring reaction in one-step ester exchange method, solves the problems of incomplete glyceride reaction, low product conversion rate and overproof monoglyceride content in fatty acid methyl ester products easily caused by the production process of the one-step ester exchange method, adopts a device for preparing fatty acid methyl ester by continuous ester exchange to carry out two-stage ester exchange reaction, has the characteristics of reasonable process, advanced equipment, complete reaction and high product conversion rate, can ensure stable and qualified product quality and meets the requirements of industrialized production, has higher popularization and application value.
Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention.
Many other changes and modifications can be made without departing from the spirit and scope of the invention. It is to be understood that the invention is not to be limited to the specific embodiments, but only by the scope of the appended claims.
Claims (4)
1. A device for preparing fatty acid methyl ester by continuous ester exchange is characterized in that: comprises a first tower type superfine contact reactor (1), a second tower type superfine contact reactor (2), a first superfine mixing reactor (3), a second superfine mixing reactor (4), a batching tank (5), a first settling separation tank (6), a second settling separation tank (7), a flash evaporation kettle (8) and a waste methanol collecting tank (9); the batching tank (5) is connected with a first conveying pump (10), a first ultramicro mixing reactor (3), a first heat exchanger (11) and the top of a first tower type superfine contact reactor (1) through pipelines, two pipelines are arranged at the bottom of the first tower type reactor (1), one pipeline is connected with the first conveying pump (10), the other pipeline is connected with a second conveying pump (12) and the top of a first sedimentation separation tank (6), the first sedimentation separation tank (6) is provided with a bottom pipeline and a side pipeline, the side pipeline is connected with a third conveying pump (13), an alcohol-alkali solution tank (21), a second ultramicro mixing reactor (4), a second heat exchanger (14) and the top of a second tower type superfine contact reactor (2), the bottom pipeline is connected with a fourth conveying pump (15), a third heat exchanger (16) and a side feed inlet of a flash evaporation kettle (8), the bottom of the second tower type superfine contact reactor (2) is provided with two pipelines, one pipeline is connected with the third delivery pump (13), the other pipeline is connected with the fourth delivery pump (15), the top of the flash kettle (8) is connected with the fourth heat exchanger (17) and the waste methanol collection tank (9) through pipelines, the waste methanol collection tank (9) is connected with the methanol distillation system (22) through the seventh delivery pump (20), the bottom of the flash kettle (8) is connected with the fifth delivery pump (18) and the top of the second settling separation tank (7) through pipelines, and the second settling separation tank (7) is respectively connected with the methyl ester rectification system (23) and the glycerol rectification system (24).
2. A method for preparing fatty acid methyl ester by continuous ester exchange is characterized by comprising the following steps:
s1: mixing glyceride and methanol according to a mass ratio of 5: 1, adding a potassium hydroxide catalyst accounting for 0.6 percent of the total amount of the reaction liquid into a proportioning tank (5), stirring and mixing uniformly, feeding the mixture into a first ultra-micro mixing reactor (3) through a first conveying pump (10), heating the mixture to 60 ℃ through a first heat exchanger (11), feeding the mixture into a first tower type ultra-fine contact reactor (1) for primary ester exchange reaction, closing a valve (25) at the bottom of the proportioning tank (5) to stop feeding when the material reaches the capacity 3/4 of the first tower type ultra-fine contact reactor (1), and sampling to detect the ester exchange reaction process;
s2: when the first-stage esterification exchange is finished, the conversion rate of the glyceride is required to be more than or equal to 85%, if the reaction does not reach the standard, a valve (25) at the bottom of the first tower type superfine contact reactor (1) is opened, the feed liquid enters the first superfine mixing reactor (3) through the first conveying pump (10) again, the feed liquid enters the top of the first tower type superfine contact reactor (1) for further circulation reaction after being heated through the first heat exchanger (11), if the temperature in the circulation process is not enough, the temperature of the first heat exchanger (11) can be heated, the reaction temperature is kept at 58-62 ℃, and when the conversion rate of the glyceride is more than or equal to 85%, the second conveying pump (12) is opened to pump the first-stage ester exchange liquid into the first settling separation tank (6) for settling for 1-2 hours, and then the lower-layer glycerol is separated and removed;
s3: and (3) pumping the primary ester exchange liquid without the glycerol in the first settling separation tank (6) into a second ultra-micro mixing reactor (4) by using a third delivery pump (13), and simultaneously mixing a potassium hydroxide methanol solution in an alcohol-alkali solution tank (21) with the primary ester exchange liquid according to the instantaneous flow rate of 1: 10, heating the mixture to 60 ℃ through a second heat exchanger (14), entering a second tower type superfine contact reactor (2) for secondary ester exchange reaction, closing a third delivery pump (13) and an eighth delivery pump at the bottom of an alcohol-alkali solution tank (21) to stop feeding when the volume of the materials reaches 3/4 of the second tower type superfine contact reactor (2), and sampling to detect the ester exchange reaction process;
s4: the conversion rate of the glyceride is required to be more than or equal to 98 percent after the second-stage ester exchange is finished, if the reaction does not reach the standard, a tower bottom valve (25) of the second tower type superfine contact reactor (2) is opened, the feed liquid enters the second superfine mixing reactor (4) through the third delivery pump (13) again, the feed liquid enters the top of the second tower type superfine contact reactor (2) for further circulating reaction after being heated through the second heat exchanger (14), if the temperature is not enough in the circulating process, the temperature can be raised through the second heat exchanger (14), the reaction temperature is kept at 58-62 ℃, when the conversion rate of the glyceride is more than or equal to 98 percent, a fourth delivery pump (15) is opened to pump the secondary ester exchange liquid into a flash evaporation kettle (8) through a third heat exchanger (16), the methanol removed by flash evaporation enters a waste methanol collecting tank (9) through a fourth heat exchanger (17) and then enters a methanol rectification system (22); and feeding the material liquid after flash evaporation into a second settling separation tank (7) by using a fifth delivery pump (18), standing and settling for 4-5 hours, feeding the waste glycerin at the bottom into a glycerin rectification system (24) by using a sixth delivery pump (19), feeding a crude fatty acid methyl ester product obtained by overflowing from an overflow port in the middle of the second settling separation tank (7) into a methyl ester rectification system (23), and rectifying and refining to obtain a fatty acid methyl ester finished product and a byproduct vegetable pitch.
3. The continuous transesterification method for obtaining fatty acid methyl esters according to claim 2, wherein the method comprises the following steps: the glyceride conversion was determined using chromatography.
4. The continuous transesterification method for obtaining fatty acid methyl esters according to claim 2, wherein the method comprises the following steps: the concentration of the potassium hydroxide methanol solution in the alcohol-alkali solution tank in the step S3 is 3%.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101058734A (en) * | 2007-05-31 | 2007-10-24 | 张付舜 | Device for industrially synthesizing biological diesel oil by microwave and method thereof |
| CN101781610A (en) * | 2010-03-16 | 2010-07-21 | 刘宽 | Continuous esterification and ester exchange process used for producing biodiesel |
| CN202465637U (en) * | 2012-01-18 | 2012-10-03 | 山东锦江生物能源科技有限公司 | Reaction device for heterogeneous ultra-refined continuous production of biodiesel |
| CN103877958A (en) * | 2014-03-12 | 2014-06-25 | 南京大学昆山创新研究院 | Catalyst for preparing biodiesel and preparation method thereof as well as preparation process of biodiesel |
| CN104120039A (en) * | 2014-07-30 | 2014-10-29 | 河北金谷再生资源开发有限公司 | Method for preparing fatty acid methyl ester through multi-stage ester exchange |
| CN104651060A (en) * | 2015-02-03 | 2015-05-27 | 江苏西方环保科技有限公司 | Biodiesel continuous ester interchange technology |
| CN106929162A (en) * | 2017-03-30 | 2017-07-07 | 迈安德集团有限公司 | A kind of utilization waste grease produces the deacidification technique of glycerine |
| CN108277090A (en) * | 2018-01-30 | 2018-07-13 | 浙江工业大学 | A kind of preparation method of low-sulphur biodiesel |
| CN108949366A (en) * | 2018-07-13 | 2018-12-07 | 中国科学院青岛生物能源与过程研究所 | A kind of ester exchange process and device can be used for producing biodiesel |
| CN111500373A (en) * | 2020-04-27 | 2020-08-07 | 浙江工业大学 | Preparation method of biodiesel |
-
2020
- 2020-11-21 CN CN202011316756.9A patent/CN112574826A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101058734A (en) * | 2007-05-31 | 2007-10-24 | 张付舜 | Device for industrially synthesizing biological diesel oil by microwave and method thereof |
| CN101781610A (en) * | 2010-03-16 | 2010-07-21 | 刘宽 | Continuous esterification and ester exchange process used for producing biodiesel |
| CN202465637U (en) * | 2012-01-18 | 2012-10-03 | 山东锦江生物能源科技有限公司 | Reaction device for heterogeneous ultra-refined continuous production of biodiesel |
| CN103877958A (en) * | 2014-03-12 | 2014-06-25 | 南京大学昆山创新研究院 | Catalyst for preparing biodiesel and preparation method thereof as well as preparation process of biodiesel |
| CN104120039A (en) * | 2014-07-30 | 2014-10-29 | 河北金谷再生资源开发有限公司 | Method for preparing fatty acid methyl ester through multi-stage ester exchange |
| CN104651060A (en) * | 2015-02-03 | 2015-05-27 | 江苏西方环保科技有限公司 | Biodiesel continuous ester interchange technology |
| CN106929162A (en) * | 2017-03-30 | 2017-07-07 | 迈安德集团有限公司 | A kind of utilization waste grease produces the deacidification technique of glycerine |
| CN108277090A (en) * | 2018-01-30 | 2018-07-13 | 浙江工业大学 | A kind of preparation method of low-sulphur biodiesel |
| CN108949366A (en) * | 2018-07-13 | 2018-12-07 | 中国科学院青岛生物能源与过程研究所 | A kind of ester exchange process and device can be used for producing biodiesel |
| CN111500373A (en) * | 2020-04-27 | 2020-08-07 | 浙江工业大学 | Preparation method of biodiesel |
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