CN107011998B

CN107011998B - Biodiesel production system

Info

Publication number: CN107011998B
Application number: CN201710312728.1A
Authority: CN
Inventors: 杨冠宇; 周红茹
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-05-05
Filing date: 2017-05-05
Publication date: 2020-07-14
Anticipated expiration: 2037-05-05
Also published as: CN107011998A

Abstract

The invention provides a biodiesel production system, which comprises a first production unit and a refined biodiesel production unit; the first production unit comprises a first esterification kettle, a first heat exchanger, a first centrifuge, a first temporary storage tank, a methanol recovery kettle, a second heat exchanger, a first dryer and a second temporary storage tank which are sequentially communicated through a pipeline, the first esterification kettle is communicated with a first methanol tank and a first catalyst adding tank through pipelines, a feeding pipe is arranged at the inlet of the first esterification kettle, the methanol recovery kettle is also communicated with a first condenser, and the first condenser is communicated with a first vacuum pump and a first methanol collecting tank; the refined biodiesel production unit comprises a heat exchanger, a short-path distiller, and a light component temporary storage tank, a heavy component temporary storage tank and a vacuum pump which are respectively communicated with the short-path distiller; the heat exchanger is communicated with the short-range distiller through a pipeline, and the second temporary storage tank is communicated with the heat exchanger through a pipeline. The invention improves the production efficiency and the product yield of the biodiesel.

Description

Biodiesel production system

Technical Field

The invention relates to the technical field of grease light chemical equipment, in particular to a biodiesel production system.

Background

Biodiesel is a typical 'green energy', is a clean and environment-friendly renewable energy source, and is generally obtained by esterification and ester exchange reaction of animal and vegetable oil. Compared with petroleum diesel, the biodiesel has the advantages of no toxicity, no sulfur, no aromatic hydrocarbon, high cetane number, good combustion performance and the like, and is an environment-friendly biofuel capable of replacing the petroleum diesel.

The biodiesel consists of C, H, O three elements, has higher oxygen content than petrochemical diesel, is favorable for promoting the complete combustion of fuel during combustion, can effectively reduce the content of hydrocarbon, carbon monoxide, inhalable particles and sulfur dioxide in exhaust gas, and simultaneously reduces the generation of substances such as carbon deposition and the like which damage engines. The biodiesel is vigorously developed in China, and has very important strategic significance for promoting economic sustainable development, promoting energy source substitution, controlling urban atmospheric pollution and relieving environmental pressure.

At present, the main raw materials for preparing the biodiesel are various waste animal and vegetable oil and byproducts in the oil refining process, such as kitchen waste oil, illegal cooking oil, frying waste oil, acidified oil, fatty acid deodorized distillate and the like.

The production method of biodiesel currently adopts an acid or base catalysis method. The used acid catalyst is usually sulfuric acid, phosphoric acid, hydrochloric acid, organic sulfonic acid and the like, wherein concentrated sulfuric acid is the most commonly used acid catalyst due to low price and abundant resources; the basic catalysts used are preferably NaOH, KOH and sodium methoxide.

The liquid alkali catalysis method has the characteristics of low reaction temperature, high speed, high yield, small corrosion to equipment and the like, but because the method can perform saponification reaction with free fatty acid in the raw oil, the reaction product is emulsified due to the existence of soap, and the subsequent separation is difficult, so the method has strict requirements on the acid value and the water content of the raw oil. The liquid acid catalysis method has lower requirements on raw materials, but has low reaction yield and serious corrosion on equipment.

For the reasons, in the industrial production of biodiesel, an acid catalyst is generally adopted, and in the equipment selection, an enamel reaction kettle is generally adopted as core equipment of esterification or ester exchange reaction, and conventional tower type or kettle type reduced pressure distillation is adopted to produce refined biodiesel. The temperature of conventional tower type reduced pressure distillation is 220-230 ℃, reflux ratio is required to be balanced in the reduced pressure distillation process, entrainment phenomenon is difficult to avoid, and indexes of three items of acid value, free glycerin and total glycerin of a product exceed standards; in the long-time distillation process, polymerization reaction can occur between carbon-carbon double bonds of unsaturated fatty acid in the crude methyl ester, so that the plant asphalt is generated, and the product yield is greatly reduced. In the production process, after the esterification or ester exchange reaction is finished, the acid or alkaline catalyst needs to be neutralized and washed by water to remove the neutralized product, so that a large amount of industrial wastewater is inevitably generated, and the cost of wastewater treatment is increased for enterprises.

In addition, the biodiesel industrially produced at present is a mixture of fatty acid methyl esters with different carbon numbers, and the product can only be sold as biodiesel, so that the additional value is generally not high.

Disclosure of Invention

The invention aims to provide a biodiesel production system, which is used for solving the problems in the prior art and improving the production efficiency and the product yield of biodiesel.

In order to achieve the purpose, the invention provides the following scheme: the invention provides a biodiesel production system, which comprises a first production unit and a refined biodiesel production unit; the first production unit comprises a first esterification kettle, a first heat exchanger, a first centrifuge, a first temporary storage tank, a methanol recovery kettle, a second heat exchanger, a first dryer and a second temporary storage tank which are sequentially communicated through a pipeline, the first esterification kettle is communicated with a first methanol tank and a first catalyst adding tank through a pipeline, a feeding pipe is arranged at the inlet of the first esterification kettle, the methanol recovery kettle is also communicated with a first condenser, and the first condenser is communicated with a first vacuum pump and a first methanol collecting tank; the refined biodiesel production unit comprises a heat exchanger, a short-path distiller, and a light component temporary storage tank, a heavy component temporary storage tank and a vacuum pump which are respectively communicated with the short-path distiller, wherein the heat exchanger is communicated with the short-path distiller through a pipeline, the light component temporary storage tank is communicated with the bottom of the short-path distiller, and the heavy component temporary storage tank is communicated with the lower part of the short-path distiller; the second temporary storage tank is communicated with the heat exchanger through a pipeline.

Preferably, the top of the first esterification kettle is also communicated with a first auxiliary material adding tank and a second condenser; a first trap is also arranged between the first condenser and the first vacuum pump; the first dryer is also communicated with a second vacuum pump; a first cold trap and a second cold trap are sequentially communicated between the short-path distiller and the vacuum pump; a light component tank is also arranged between the short-path distiller and the light component temporary storage tank; and a heavy component tank is also arranged between the short-path distiller and the heavy component temporary storage tank.

Preferably, the inlet pipe, the pipeline between first methyl alcohol jar and the first cauldron of esterifying, the pipeline between first cauldron of esterifying and the first heat exchanger, the pipeline between first jar of keeping in and the methyl alcohol recovery cauldron, the pipeline between methyl alcohol recovery cauldron and the second heat exchanger, the pipeline between first desicator and the second jar of keeping in, the second jar of keeping in with the pipeline between the heat exchanger the light component jar with the pipeline between the light component jar of keeping in and the heavy component jar with all be provided with the pump on the pipeline between the heavy component jar of keeping in.

Preferably, the system also comprises a second production unit arranged between the first production unit and the refined biodiesel production unit, wherein the second production unit comprises a second methanol tank, a second esterification kettle, a third heat exchanger, a first filter, a third temporary storage tank, a fourth heat exchanger, a second dryer and a fourth temporary storage tank which are sequentially communicated through a pipeline, the second esterification kettle is communicated with the second temporary storage tank, and the fourth temporary storage tank is communicated with the heat exchanger; the second esterification kettle is further communicated with a second catalyst adding tank, a second auxiliary material adding tank, a third condenser and a fourth condenser, the fourth condenser is communicated with a third vacuum pump and a second methanol collecting tank, the fourth condenser is communicated with a second catcher between the third vacuum pump, and the second dryer is communicated with a fourth vacuum pump.

Preferably, a pipeline between the second temporary storage tank and the second esterification kettle, a pipeline between the second methanol tank and the second esterification kettle, a pipeline between the second esterification kettle and the third heat exchanger, a pipeline between the third temporary storage tank and the fourth heat exchanger, and a pipeline between the second dryer and the fourth temporary storage tank are all provided with pumps.

Preferably, the system also comprises a first refining unit, the structure composition of the first refining unit is completely the same as that of the refined biodiesel production unit, and a light component temporary storage tank in the refined biodiesel production unit is connected with a heat exchanger in the first refining unit through a pipeline.

Preferably, the system further comprises a second refining unit, the second refining unit and the first refining unit have the same structural composition, and the light component temporary storage tank in the first refining unit is connected with the heat exchanger in the second refining unit through a pipeline.

Preferably, the device further comprises a pretreatment unit, wherein the pretreatment unit comprises a fifth heat exchanger, a second filter, a fifth temporary storage tank, an oil refining pot, a sixth heat exchanger, a second centrifuge, a sixth temporary storage tank, a seventh heat exchanger, a third dryer and a seventh temporary storage tank which are sequentially communicated through pipelines, the oil refining pot is communicated with an acid feeding pipe, the third dryer is communicated with a fifth vacuum pump, and the seventh temporary storage tank is communicated with a feeding pipe of the first esterification kettle.

Preferably, the feeding pipe of the fifth heat exchanger, the pipeline between the fifth temporary storage tank and the oil refining kettle, the acid feeding pipe, the pipeline between the oil refining kettle and the sixth heat exchanger, the pipeline between the sixth temporary storage tank and the seventh heat exchanger, and the pipeline between the third dryer and the seventh temporary storage tank are all provided with pumps.

Compared with the prior art, the biodiesel production system has the following beneficial effects:

1) the entrainment phenomenon can be effectively avoided in the purification and refining processes of the biodiesel, so that the indexes of acid value, soap content, free glycerin and total glycerin are ensured to meet the BD100 requirement;

2) the temperature of the short-path distillation is 160-170 ℃ at most, the separation temperature is lower, and the distillation separation time is shorter (generally about ten seconds);

3) the short-path distillation can effectively prevent the polymerization of materials and avoid the generation of plant asphalt, thereby improving the product yield;

4) direct steam is not needed in the short-path distillation, so that water pollution and air pollution are avoided;

5) the method can realize the accurate separation of the methyl palmitate, the methyl oleate, the methyl linoleate and the methyl stearate from the mixed fatty acid methyl ester, and obviously improve the enterprise benefit;

6) the whole set of production equipment and production process has no wastewater discharge and is environment-friendly.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic diagram of a first production unit of a biodiesel production system according to the present invention;

FIG. 2 is a schematic diagram of the structure of a refined biodiesel production unit in the biodiesel production system of the present invention;

FIG. 3 is a schematic diagram of a second production unit in the biodiesel production system of the present invention;

FIG. 4 is a schematic structural view of a first refining unit in the biodiesel production system of the present invention;

FIG. 5 is a schematic structural view of a second refining unit in the biodiesel production system of the present invention;

FIG. 6 is a schematic view showing the structure of a pretreatment system in the biodiesel production system of the present invention;

the method comprises the following steps of 100-a first production unit, 101-a first methanol tank, 102-a first esterification kettle, 103-a first heat exchanger, 104-a first centrifuge, 105-a first temporary storage tank, 106-a methanol recovery kettle, 107-a second heat exchanger, 108-a first dryer, 109-a second temporary storage tank, 110-a first catalyst adding tank, 111-a first auxiliary material adding tank, 112-a second condenser, 113-a first condenser, 114-a first vacuum pump, 115-a first trap, 116-a first methanol collecting tank and 117-a second vacuum pump;

200-refined biodiesel production unit, 201-heat exchanger, 202-short path distiller, 203-vacuum pump, 204-light component temporary storage tank, 205-heavy component temporary storage tank, 206-first cold trap, 207-second cold trap, 208-light component tank, 209-heavy component tank;

300-a second production unit, 301-a second methanol tank, 302-a second esterification kettle, 303-a third heat exchanger, 304-a first filter, 305-a third temporary storage tank, 306-a fourth heat exchanger, 307-a second dryer, 308-a fourth temporary storage tank, 309-a second catalyst addition tank, 310-a second auxiliary material addition tank, 311-a third condenser, 312-a fourth condenser, 313-a second trap, 314-a third vacuum pump, 315-a second methanol collection tank, and 316-a fourth vacuum pump;

400-a first refining unit, 401-a first refining unit heat exchanger, 402-a first refining unit short-path distiller, 403-a first refining unit vacuum pump, 404-a first refining unit light component temporary storage tank, 405-a first refining unit heavy component temporary storage tank, 406-a first refining unit first cold trap, 407-a first refining unit second cold trap, 408-a first refining unit light component tank, 409-a first refining unit heavy component tank;

500-a second refining unit, 501-a second refining unit heat exchanger, 502-a second refining unit short-path distiller, 503-a second refining unit vacuum pump, 504-a second refining unit light component temporary storage tank, 505-a second refining unit heavy component temporary storage tank, 506-a second refining unit first cold trap, 507-a second refining unit second cold trap, 508-a second refining unit light component tank, 509-a second refining unit heavy component tank;

600-pretreatment unit, 601-fifth heat exchanger, 602-second filter, 603-fifth temporary storage tank, 604-oil refining kettle, 605-sixth heat exchanger, 606-second centrifuge, 607-sixth temporary storage tank, 608-seventh heat exchanger, 609-third dryer, 610-seventh temporary storage tank and 611-fifth vacuum pump.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide a biodiesel production system, which aims to solve the problems in the prior art and improve the production efficiency and the product yield of biodiesel.

The invention provides a biodiesel production system, which comprises a first production unit and a refined biodiesel production unit; the first production unit comprises a first esterification kettle, a first heat exchanger, a first centrifuge, a first temporary storage tank, a methanol recovery kettle, a second heat exchanger, a first dryer and a second temporary storage tank which are sequentially communicated through a pipeline, the first esterification kettle is communicated with a first methanol tank and a first catalyst adding tank through a pipeline, a feeding pipe is arranged at the inlet of the first esterification kettle, the methanol recovery kettle is also communicated with a first condenser, and the first condenser is communicated with a first vacuum pump and a first methanol collecting tank; the refined biodiesel production unit comprises a heat exchanger, a short-path distiller, and a light component temporary storage tank, a heavy component temporary storage tank and a vacuum pump which are respectively communicated with the short-path distiller, wherein the heat exchanger is communicated with the short-path distiller through a pipeline, the light component temporary storage tank is communicated with the bottom of the short-path distiller, and the heavy component temporary storage tank is communicated with the lower part of the short-path distiller; the second temporary storage tank is communicated with the heat exchanger through a pipeline.

The method takes the short-path distiller as core equipment to purify and refine the biodiesel, the temperature of the short-path distillation is 160-170 ℃ at most, the separation temperature is lower, the distillation separation time is shorter (about ten seconds generally), and the production efficiency is improved; the short-path distillation can effectively prevent the polymerization of materials and avoid the generation of plant asphalt, thereby improving the product yield.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

The first embodiment is as follows:

the present embodiment provides a biodiesel production system, comprising a first production unit 100 and a refined biodiesel production unit;

as shown in fig. 1, the first production unit 100 includes a first esterification reactor 102, a first heat exchanger 103, a first centrifuge 104, a first temporary storage tank 105, a methanol recovery reactor 106, a second heat exchanger 107, a first dryer 108 and a second temporary storage tank 109 which are sequentially communicated through a pipeline, the first esterification reactor 102 is communicated with a first methanol tank 101 and a first catalyst addition tank 110 through a pipeline, an inlet pipe is arranged at an inlet of the first esterification reactor 102, the methanol recovery reactor 106 is further communicated with a first condenser 113, and the first condenser 113 is communicated with a first vacuum pump 114 and a first methanol collection tank 116; the top of the first esterification kettle 102 is also communicated with a first auxiliary material adding tank 111 and a second condenser 112; the first dryer 108 is also communicated with a second vacuum pump 117; the feed pipe, the pipeline between the first methanol tank 101 and the first esterification kettle 102, the pipeline between the first esterification kettle 102 and the first heat exchanger 103, the pipeline between the first temporary storage tank 105 and the methanol recovery kettle 106, the pipeline between the methanol recovery kettle 106 and the second heat exchanger 107, and the pipeline between the first dryer 108 and the second temporary storage tank 109 are all provided with pumps.

The degummed dried raw material oil is pumped into the first esterification reactor 102 through the feed pipe, and is mixed with methanol pumped into the first esterification reactor 102 from the first methanol tank 101 in the first esterification reactor 102, and the degummed dried raw material oil and the methanol are subjected to esterification reaction under the action of the catalyst added through the first catalyst addition tank 110. The reacted materials are pumped into a first heat exchanger 103, the temperature of the reacted materials is raised to a proper temperature through the first heat exchanger 103, the reacted materials enter a first centrifuge 104 for separation, the separated crude biodiesel enters a first temporary storage tank 105, and a byproduct is mainly glycerol and can be directly sold outside. The crude biodiesel from the first temporary storage tank 105 is pumped into a methanol recovery tank 106, and under the vacuum condition provided by a first vacuum pump 114, the gasified methanol is condensed by a second condenser 112 and then changed into liquid, and the liquid flows into a first methanol collection tank 116 for further rectification treatment. After the methanol recovery is finished, the crude biodiesel is pumped into the second heat exchanger 107, the temperature of the crude biodiesel is raised to a proper temperature through the second heat exchanger 107, the crude biodiesel enters the first dryer 108, under the vacuum condition provided by the second vacuum pump 117, moisture and small molecule volatile matters are removed, and the dried crude biodiesel is pumped into the second temporary storage tank 109.

The first esterification kettle 102 is provided with a mesh jacket layer inside the kettle body, and after the esterification reaction is finished, solid catalysts such as solid acid or immobilized lipase and the like can be retained in the mesh jacket layer, so that the separation of materials and the catalysts is realized, and the low loss and the reutilization of the catalysts are ensured.

The top of the first esterification kettle 102 is provided with a first condenser 113, which has the function of condensing methanol vapor in the esterification reaction process into liquid and refluxing the liquid to the inside of the first esterification kettle 102, so that the methanol loss in the esterification process can be reduced.

The top of first esterification kettle 102 still is provided with first auxiliary material and adds jar 111, can hold the auxiliary material kind and the quantity that need add according to the difference of the nature of material and reaction process is nimble, ensures esterification reaction's effect and the performance of product biodiesel.

A first trap 115 is arranged between the first vacuum pump 114 and the second condenser 112, and the first trap 115 can effectively trap uncondensed methanol vapor and ensure the vacuum degree of the system.

As shown in fig. 2, the refined biodiesel production unit 200 comprises a heat exchanger 201, a short-path distiller 202, and a light component temporary storage tank 204, a heavy component temporary storage tank 205 and a vacuum pump 203 which are respectively communicated with the short-path distiller 202, wherein the heat exchanger 201 is communicated with the short-path distiller 202 through a pipeline, the light component temporary storage tank 204 is communicated with the bottom of the short-path distiller 202, and the heavy component temporary storage tank 205 is communicated with the lower part of the short-path distiller 202; the second temporary storage tank 109 is communicated with the heat exchanger 201 through a pipeline; a light component tank 208 is also arranged between the short-path distiller 202 and the light component temporary storage tank 204; a heavies tank 209 is also provided between the short path still 202 and the heavies hold tank 205. Pumps are arranged on a pipeline between the second temporary storage tank 109 and the heat exchanger 201, a pipeline between the light component tank 208 and the light component temporary storage tank 204, and a pipeline between the heavy component tank 209 and the heavy component temporary storage tank 205.

The dry crude biodiesel is pumped into the heat exchanger 201 from the second temporary storage tank 109, is heated to a proper temperature through the heat exchanger 201, enters the short-path distiller 202, and is differentiated to obtain a first light component substance and a first heavy component substance under the vacuum condition provided by the vacuum pump 203. The first light component substance is the biodiesel, and the first heavy component substance is the mixture of sterol, vitamin E, etc. The first lights stream flows into the lights holding tank 208 and is then pumped into the lights holding tank 204. The first heavies material flows into the heavies tank 209 and is then pumped into the heavies hold tank 205 for sale as a by-product.

The short-path distillation is close to the ultimate vacuum separation, the separation temperature is lower, the distillation separation time is shorter (generally about ten seconds), the polymerization reaction of unsaturated fatty acid carbon-carbon double bonds in the crude methyl ester can be effectively prevented, and the generation of plant asphalt is avoided. According to the production practice, the product yield of the two distillation modes is different by about 6 percent (the product yield of molecular distillation is higher than that of the ordinary tower type reduced pressure distillation).

Between the short path distiller 202 and the vacuum pump 203, there are provided a first cold trap 206 and a second cold trap 207 which can effectively trap condensable gas components from the short path distiller 202, ensuring the degree of vacuum of the system.

In view of more raw material sources for biodiesel production and larger fluctuation of the acid value of the raw material, a secondary esterification process is required for the raw material with higher acid value (generally more than 60 mgKOH/g) to ensure that the product index can reach the BD100 requirement. Therefore, for the raw material with a high acid value (generally above 60 mgKOH/g), the second production unit 300 is added between the first production unit 100 and the refined biodiesel production unit 200 in this embodiment.

As shown in fig. 3, the second production unit 300 comprises a second methanol tank 301, a second esterification kettle 302, a third heat exchanger 303, a first filter 304, a third temporary storage tank 305, a fourth heat exchanger 306, a second dryer 307 and a fourth temporary storage tank 308 which are sequentially communicated through pipelines, wherein the second esterification kettle 302 is communicated with the second temporary storage tank 109, and the fourth temporary storage tank 308 is communicated with the heat exchanger; the second esterification kettle 302 is also communicated with a second catalyst adding tank 309, a second auxiliary material adding tank 310, a third condenser 311 and a fourth condenser 312, the fourth condenser 312 is communicated with a third vacuum pump 314 and a second methanol collecting tank 315, a second catcher 313 is communicated between the fourth condenser 312 and the third vacuum pump 314, and a fourth vacuum pump 316 is communicated with a second dryer 307; a pipeline between the second temporary storage tank 109 and the second esterification kettle 302, a pipeline between the second methanol tank 301 and the second esterification kettle 302, a pipeline between the second esterification kettle 302 and the third heat exchanger 303, a pipeline between the third temporary storage tank 305 and the fourth heat exchanger 306, and a pipeline between the second dryer 307 and the fourth temporary storage tank 308 are all provided with pumps.

The dry crude biodiesel is pumped from the second temporary storage tank 109 into the second esterification reactor 302, mixed with methanol pumped from the second methanol tank 301 into the second esterification reactor 302 in the second esterification reactor 302, and subjected to esterification reaction under the action of the catalyst added via the second catalyst addition tank 309. After the reaction is finished, the second auxiliary material adding tank 310 is used for adding auxiliary materials to stop the reaction, and under the vacuum condition provided by the third vacuum pump 314, the gasified methanol is condensed by the fourth condenser 312 to become liquid and flows into the second methanol tank 301 for further rectification treatment. The crude biodiesel from which methanol is recovered is pumped into a third heat exchanger, heated to a suitable temperature by a third heat exchanger 303, and then enters a first filter 304, and after filtration is completed, the crude biodiesel enters a third temporary storage tank 305. The crude biodiesel in the third temporary storage tank 305 is pumped into a fourth heat exchanger 306, the temperature of the crude biodiesel is raised to a proper temperature through the fourth heat exchanger 306, the crude biodiesel enters a second dryer 307, moisture and small molecule volatile matters are removed under the vacuum condition provided by a fourth vacuum pump 316, and the dried crude biodiesel is pumped into a fourth temporary storage tank 308.

In order to increase the added value of the biodiesel product, the inventor further refines the first light component substance obtained by the refined biodiesel extraction unit 200 by using the first refining unit 400 and the second refining unit 500 to subdivide and obtain methyl palmitate, methyl oleate, methyl linoleate and methyl stearate products with high purity and excellent color.

As shown in fig. 4 and 5, the first refining unit 400, the second refining unit 500 and the refined biodiesel production unit 200 have the same structural composition, the light component temporary storage tank 204 in the refined biodiesel production unit 200 is connected with the heat exchanger 401 in the first refining unit through a pipeline, and the light component temporary storage tank 404 in the first refining unit is connected with the heat exchanger 501 in the second refining unit through a pipeline.

The first light component substance 400 is pumped into the first refining unit heat exchanger 401 from the light component temporary storage tank 204, is heated to a proper temperature through the first refining unit heat exchanger 401, enters the first refining unit short-distance distiller 402, and is differentiated under the vacuum condition provided by the first refining unit vacuum pump 403 to obtain a second light component substance and a second heavy component substance. The second light component substance is a mixture of methyl palmitate, methyl oleate and methyl linoleate, and the second heavy component substance is methyl stearate. The second light component material flows into the first polishing unit light component tank 408 and is then pumped into the first polishing unit light component holding tank 404. The second heavy component material flows into the first polishing unit heavy component tank 409 and is then pumped into the first polishing unit heavy component holding tank 405. The first refining unit first cold trap 406 and the first refining unit second cold trap 407 can effectively trap the condensable gas components from the first refining unit short-path distiller 402, ensuring the vacuum degree of the system.

The second light component substance in the first refining unit light component temporary storage tank 404 is pumped into the second refining unit heat exchanger 501, is heated to a proper temperature through the second refining unit heat exchanger 501, then enters the second refining unit short-distance distiller 502, and is differentiated to obtain a third light component substance and a third heavy component substance under the vacuum condition provided by the second refining unit vacuum pump 503. The third light component substance is methyl palmitate, and the third heavy component substance is a mixture of methyl oleate and methyl linoleate. The third light component material flows into the second polishing unit light component tank 508 and is then pumped into the second polishing unit light component holding tank 504. The third heavy component material flows into the second refining unit heavy component tank 509 and is pumped into the second refining unit heavy component holding tank 505. The second refining unit first cold trap 506 and the second refining unit second cold trap 507 can effectively trap condensable gas components from the second refining unit short-path distiller 502, and the vacuum degree of the system is ensured.

In the biodiesel raw material procurement process, there are many raw materials that have not been pretreated, such as frying waste oil, waste cooking oil, etc., and such raw materials must be treated by the pretreatment unit 600 to remove gum impurities therefrom before entering the biodiesel production system.

As shown in fig. 6, the pretreatment unit 600 comprises a fifth heat exchanger 601, a second filter 602, a fifth temporary storage tank 603, an oil refining kettle 604, a sixth heat exchanger 605, a second centrifuge 606, a sixth temporary storage tank 607, a seventh heat exchanger 608, a third dryer 609 and a seventh temporary storage tank 610 which are sequentially communicated through a pipeline, the oil refining kettle 604 is communicated with an acid feed pipe, the third dryer 609 is communicated with a fifth vacuum pump 611, and the seventh temporary storage tank 610 is communicated with a feed pipe of the first esterification kettle 102; and pumps are arranged on a feeding pipe of the fifth heat exchanger 601, a pipeline between the fifth temporary storage tank 603 and the oil refining pan 604, an acid feeding pipe, a pipeline between the oil refining pan 604 and the sixth heat exchanger 605, a pipeline between the sixth temporary storage tank 607 and the seventh heat exchanger 608, and a pipeline between the third dryer 609 and the seventh temporary storage tank 610.

After being pumped into the fifth heat exchanger 601, the raw oil is heated to a proper temperature by the fifth heat exchanger 601 and then enters the second filter 602, after being filtered, the raw oil enters the fifth temporary storage tank 603, and then the raw oil in the fifth temporary storage tank 603 is pumped into the oil refining kettle 604, and undergoes degumming reaction with acid (aqueous solution of phosphoric acid, citric acid or oxalic acid, etc.) pumped into the oil refining kettle 604 in the oil refining kettle 604. The reacted materials are pumped out of the oil refining pot 604 and enter the sixth heat exchanger 605, the temperature of the reacted materials is raised to a proper temperature through the sixth heat exchanger 605 and then enter the second centrifuge 606 for separation, the separated degummed raw oil enters the sixth temporary storage tank 607, and the by-products are mainly phospholipid and can be sold directly. The degummed raw oil is pumped out of the sixth temporary storage tank 607 to enter the seventh heat exchanger 608, the degummed raw oil is heated to an appropriate temperature through the seventh heat exchanger 608 and then enters the third dryer 609, under the vacuum condition provided by the fifth vacuum pump 611, moisture and small molecule volatile matters are removed, and the dried degummed raw oil is pumped into the seventh temporary storage tank 610 to be prepared to enter the first production system 100.

In the description of the present invention, it should be noted that the terms "top", "bottom", and the like refer to orientations or positional relationships based on those shown in the drawings, and are used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," "seventh," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims

1. A biodiesel production system characterized by: comprises a first production unit and a refined biodiesel production unit;

the first production unit comprises a first esterification kettle, a first heat exchanger, a first centrifuge, a first temporary storage tank, a methanol recovery kettle, a second heat exchanger, a first dryer and a second temporary storage tank which are sequentially communicated through a pipeline, the first esterification kettle is communicated with a first methanol tank and a first catalyst adding tank through a pipeline, a feeding pipe is arranged at the inlet of the first esterification kettle, the methanol recovery kettle is also communicated with a first condenser, and the first condenser is communicated with a first vacuum pump and a first methanol collecting tank;

the refined biodiesel production unit comprises a heat exchanger, a short-path distiller, and a light component temporary storage tank, a heavy component temporary storage tank and a vacuum pump which are respectively communicated with the short-path distiller, wherein the heat exchanger is communicated with the short-path distiller through a pipeline, the light component temporary storage tank is communicated with the bottom of the short-path distiller, and the heavy component temporary storage tank is communicated with the lower part of the short-path distiller; the second temporary storage tank is communicated with the heat exchanger through a pipeline;

the top of the first esterification kettle is also communicated with a first auxiliary material adding tank and a second condenser; a first trap is also arranged between the first condenser and the first vacuum pump; the first dryer is also communicated with a second vacuum pump; a first cold trap and a second cold trap are sequentially communicated between the short-path distiller and the vacuum pump; a light component tank is also arranged between the short-path distiller and the light component temporary storage tank; and a heavy component tank is also arranged between the short-path distiller and the heavy component temporary storage tank.

2. The biodiesel production system of claim 1, wherein: pipeline between inlet pipe, first methyl alcohol jar and the first cauldron of esterifying, pipeline between first cauldron and the first heat exchanger of esterifying, pipeline between first jar and the methyl alcohol recovery cauldron of keeping in, pipeline between methyl alcohol recovery cauldron and the second heat exchanger, pipeline between first desicator and the second jar of keeping in, the second keep in the jar with pipeline between the heat exchanger the light component jar with pipeline between the light component jar of keeping in between the jar reaches the heavy component jar with all be provided with the pump on the pipeline between the heavy component jar of keeping in.

3. The biodiesel production system of claim 1, wherein: the second production unit comprises a second methanol tank, a second esterification kettle, a third heat exchanger, a first filter, a third temporary storage tank, a fourth heat exchanger, a second dryer and a fourth temporary storage tank which are sequentially communicated through a pipeline, the second esterification kettle is communicated with the second temporary storage tank, and the fourth temporary storage tank is communicated with the heat exchanger; the second esterification kettle is further communicated with a second catalyst adding tank, a second auxiliary material adding tank, a third condenser and a fourth condenser, the fourth condenser is communicated with a third vacuum pump and a second methanol collecting tank, the fourth condenser is communicated with a second catcher between the third vacuum pump, and the second dryer is communicated with a fourth vacuum pump.

4. The biodiesel production system of claim 3, wherein: and pumps are arranged on a pipeline between the second temporary storage tank and the second esterification kettle, a pipeline between the second esterification kettle and the third heat exchanger, a pipeline between the third temporary storage tank and the fourth heat exchanger and a pipeline between the second dryer and the fourth temporary storage tank.

5. The biodiesel production system according to any one of claims 1 to 4, wherein: still include first refining unit, first refining unit with the structure of smart biodiesel production unit constitutes completely the same, light component in the smart biodiesel production unit keeps in the jar with heat exchanger in the first refining unit passes through the tube coupling.

6. The biodiesel production system of claim 5, wherein: the light component temporary storage tank in the first refining unit is connected with the heat exchanger in the second refining unit through a pipeline.

7. The biodiesel production system of claim 6, wherein: still include the preprocessing unit, the preprocessing unit includes that the fifth heat exchanger, second filter, the fifth that loop through the pipeline intercommunication keeps in jar, oil refining pot, sixth heat exchanger, second centrifuge, the sixth jar of keeping in, seventh heat exchanger, third desicator and the seventh jar of keeping in, oil refining pot intercommunication has the sour inlet pipe, third desicator intercommunication has the fifth vacuum pump, the seventh jar of keeping in with the inlet pipe intercommunication of first esterification kettle.

8. The biodiesel production system of claim 7, wherein: and pumps are arranged on the feeding pipe of the fifth heat exchanger, the pipeline between the fifth temporary storage tank and the oil refining kettle, the acid feeding pipe, the pipeline between the oil refining kettle and the sixth heat exchanger, the pipeline between the sixth temporary storage tank and the seventh heat exchanger, and the pipeline between the third dryer and the seventh temporary storage tank.