CN101654625B

CN101654625B - Method for refining biodiesel

Info

Publication number: CN101654625B
Application number: CN2008102143184A
Authority: CN
Inventors: 张伟民
Original assignee: Taiwan Wolmo Co Ltd
Current assignee: Taiwan Wolmo Co Ltd
Priority date: 2008-08-22
Filing date: 2008-08-22
Publication date: 2013-08-07
Anticipated expiration: 2028-08-22
Also published as: CN101654625A

Abstract

The invention discloses a method for refining biodiesel, comprising the following steps: (1) after heating animal and vegetable fats to 55 DEG C, mixing the animal and vegetable fats with methyl mixture additives for transesterification; (2) using stack disc separators to separate the semi-finished products of the biodiesel from the products of the transesterification to obtain the semi-finished products of the biodiesel; (3) washing and separating the semi-finished biodiesel a plurality of times and then carrying out film vacuum drying on the washed semi-finished biodiesel, thus obtaining the biodiesel, wherein, the methyl mixture additives are obtained by mixing and then stirring potassium hydroxide and methane. Compared with the current methods for refining the biodiesel, the method of the invention is smoother, simpler and more efficient, and enables the production management to become quite easy with the aid of mechanical equipment, thus effectively reducing the production cost.

Description

A kind of process for extracting of biofuel

Technical field

The present invention relates to a kind of process for extracting of biofuel, relate in particular to and a kind of vegetable and animals oils or discarded edible oil are changed into the process for extracting of biofuel, belong to petrochemical industry.

Background technology

Have much for the production of method of bio-diesel oil at present, but basic principle of work all is with the vegetable and animals oils transesterificationization, it also is the fatty acid methyl ester that the triglyceride in the vegetable and animals oils is transformed the refining of growing up, become the biofuel that is fit to as right material, and then remove with WATER-WASHING METHOD or with colloid and material such as Zi alcohol that biological Enzyme will be wherein, again biofuel is carried out drying at last and form.

Owing to need the reaction times more than 6 hours in the process of biofuel transesterificationization, and can't carry out the water washing process in an inferior stage before ending in the reaction times, therefore, all be to produce with the method for batch group formula traditionally in the arrangement of processing procedure, need to consume the time of waiting for.

On the other hand, normally carry out with stirrer in washing or with the processing procedure that biological Enzyme comes unstuck, stirring action need carry out slowly, fully with till water or biological Enzyme contacts the process of finishing washing, this process also needs to expend the time of waiting for even stirring colloid in biofuel and Zi alcohol.

In order to remedy the neutral gear of waiting time, the dealer need do transesterification groove and washing bath capacity very big usually, makes equipment manufacturing cost significantly improve, and is also very unfavorable to the investor.

Summary of the invention

In order to overcome the existing in prior technology defective, the present invention proposes a kind of mode of production continuously and carries out the transesterification process, and uses clarifixator to carry out moment and finish the washing processing procedure of comprehensive engagement to replace the processing procedure that tradition is washed with the stirrer stirring; In addition, at needs the biofuel work in-process are left standstill, so that with biofuel and saponification glycerol mixture separating process, or the biofuel after the water washing process left standstill so that the mode that biofuel is separated with water and natural glue, also replace with disc formula separating centrifuge (DISCBOWLSEPARATOR), so that moment, just above-mentioned two or more mixture can be separated.Therefore, it is smooth and efficient that whole processing procedure becomes, and the power-assisted by mechanical means makes production management become and is easy to carry out, the dealer can be reduced production costs.

Technical problem to be solved by this invention is achieved through the following technical solutions:

A kind of process for extracting of biofuel comprises: mix with the methyl mixture additive after (1) is heated to 55 ℃ with animal-plant oil and carry out transesterification; Wherein, described methyl mixture additive is stirred together and is got by potassium hydroxide and methanol mixed; (2) with disc formula separating centrifuge the biofuel work in-process are separated from the transesterification product, obtained the biofuel work in-process; (3) the work in-process biofuel is carried out repeatedly washing and separating treatment, and then, the work in-process biofuel after will washing is again carried out the film vacuum drying treatment, namely.

In the above-mentioned process for extracting, in the step (1), preferred, the consumption of potassium hydroxide accounts for 0.5～0.6% of animal-plant oil gross weight, and the consumption of methyl alcohol accounts for 18～20% of animal-plant oil gross weight;

The time of described transesterification is preferably 6～12 hours, and stirrer starts and stirs at a slow speed in the transesterification process;

Biofuel work in-process separation steps in addition from the transesterification product just in the step (2) is preferably, and finishes in the disc formula of the sending into separating machine that the reaction product of transesterificationization continues and carries out centrifugation; The biofuel that this proportion is lighter is taken in the position of whizzer dish body central authorities in whizzer, pushed then to enter in the pipeline to enter in the clarifixator via control valve and contacted with washing water, washing water then are that the saponification glycerol mixture that proportion is heavier then is discharged from whizzer by in the washing water storage tanks and send into clarifixator by transferpump via control valve.

Washing required equipment described in the step (3) comprises three groups of disc formula separating centrifuges (StackDiscSeparator), two groups of clarifixators, three biofuel work in-process blending grooves, washing water storage tank (WTK), five groups of recycle pumps, and other pipe fitting, control valve etc.

The biofuel of this washing is admitted among the biofuel work in-process blending groove in the step (3), material is sent into disc formula separating centrifuge via control valve to be separated, because biofuel proportion is lighter, in the high speed centrifugation process, taken in after the whizzer position intermediate, being thrown out of whizzer enters in the clarifixator via control valve, simultaneously, because the washing water proportion that contains xanthan gum is heavier, therefore pushed enter side outside the whizzer disc be thrown out of then release that whizzer continued then via control valve to whizzer.

Be trimmed to the molecule of biofuel little of the size near 5 μ (5/1000mm) with clarifixator in the step (3), so that can fill part with the water molecules of washing water contacts, the mixture of biofuel, water and the natural glue of finishing contact and washing is then sent into next disc formula whizzer again and is carried out liquid/liquid separation, the biofuel that proportion is lighter is sent into clarifixator and is carried out next one washing processing procedure, by that analogy.

In the step (3) this biofuel drying process need with equipment comprise a biofuel work in-process blending groove, one group of preheater, a thin-film evaporator, one group of plate-type heat exchanger, one group of biofuel finished product temporary tank, one forms product transfers to pump, one group of waste water temporary tank, one group of waste water pump, one group of vacuum pump, one group of gas-liquid separator, one group of heat transfer oil heater, one group of thermal oil recycle pump, one group of transferpump, one group of thermal oil expansion slot, one group of cooling tower, two groups of cooling water circulating pumps, and pipeline, spare parts such as control valve.

Film vacuum drying treatment described in the step (3) is: the biofuel work in-process are sent in the preheater with transferpump carried out indirect heat exchange with thermal oil, allow the biofuel work in-process that leave preheater maintain 95 ℃, enter thin-film evaporator again, entering biofuel in the thin-film evaporator cylinder body is spread to film and is evenly spread upon in the thin-film evaporator cylinder body, contained moisture content is that start vaporizer enters outside heat exchanger and is condensed at 95 ℃ in the biofuel, the biofuel film of failing to be evaporated then slides along the film evaporator inboard wall of cylinder block and falls into biofuel finished product temporary tank, finishes dehydrating processing procedure.

Description of drawings

Fig. 1 is the refinement processing flow synoptic diagram of biofuel of the present invention;

Fig. 2 is the cell schematics of vegetable and animals oils esterification process for extracting of the present invention;

Fig. 3 is biofuel centrifugation of the present invention and washing methods cell schematics;

Fig. 4 is biofuel drying process cell schematics of the present invention.

Description of reference numerals: vegetable and animals oils esterification manufacture procedure unit 100; Biofuel centrifugation and washing process unit 200; Biofuel drying process unit 300; Animal-plant oil storage tanks 1; Preheater 2,2b; Heat transfer oil heater 3,37; Thermal oil expansion slot 4,4b; Potassium hydroxide (KOH) storage tanks 5; The spiral transferpump 6 of potassium hydroxide; Methyl alcohol (Methane) storage tanks 7; Methyl mixture additive blending groove 8; Agitator 81; Esterification blending groove 9 (totally 6 91-96); Stirrer 911; Disc

formula separating centrifuge

10,17,18,19; Clarifixator 11,20,21; Transferpump 12a, 12b, 12c, 12d; Thermal oil recycle pump 12e, 12o;

Recycle pump

12f, 12g, 12h, 12i, 12j, 12k, 121; Waste water pump 12m; Finished product is transferred to pump 12n; Cooling water circulating pump 12p, 12q;

Control valve

13,15,26,27,28; Washing water storage tanks 14; Biofuel work in-process blending groove; 22,23,24,29; Thin-film evaporator 30; Plate-type heat exchanger 31; Cooling tower 32; Biofuel finished product temporary tank 33; Waste water temporary tank 34; Gas-liquid separator 35; Vacuum pump 36.

Embodiment

Relevant technology contents of the present invention and bright in detail now cooperates graphic being described as follows:

Seeing also first figure, is the refinement processing flow synoptic diagram of biofuel of the present invention.As shown in the figure: the refinement processing procedure of biofuel of the present invention comprises a vegetable and animals oils transesterification process unit 100, one biological diesel oil centrifugation and washing process unit 200, reaches a biological diesel oil drying process unit 300.

At first, see also the relevant vegetable and animals oils transesterification process unit synoptic diagram of the present invention of second figure.As shown in the figure: the required major equipment of this unit processing procedure comprises an animal-plant oil storage tanks 1, a preheater 2, a heat transfer oil heater 3, a thermal oil expansion slot 4, a potassium hydroxide (KOH) storage tanks 5, the spiral transferpump 6 of a potassium hydroxide, a methyl alcohol (Methane) storage tanks 7, a methyl mixture additive blending groove 8, one agitator 81, many group esterification blending grooves 9 (comprising 91-96), one group of disc formula separating centrifuge 10, one group of clarifixator 11, and many groups are for delivery of the transferpump 12a～12d of fluid, thermal oil recycle pump 12e, and required pipeline, peripheral equipments such as control valve.

During actual job, in animal-plant oil storage tanks 1, put into the vegetable and animals oils through pre-treatment and filtration, in potassium hydroxide storage tanks 5, put into the solid-state potassium hydroxide KOH of purity more than 92%, in methyl alcohol (Methane) storage tanks 7, put into the methyl alcohol of purity more than 100%, and suck thermal oil falling heat-transfer oil pipeline by the outside via thermal oil recycle pump 12e.

When operation begins, starting thermal oil recycle pump 12e earlier begins to allow thermal oil via preheater 2, and enter thermal oil expansion slot 4 and return in the heat transfer oil heater 3 and to form the Self body circulation, starting heat transfer oil heater 3 simultaneously allows thermal oil rising temperature to 75-80 ℃, begin to start transferpump 12c then in order to transferring raw material oil, allow the vegetable and animals oils be to enter esterification blending groove 9 after raw material is increased to 55 ℃ via preheater 2 with the grease temperature again, allow the stock oil that has heated charge into esterification blending groove 91-96 by the control by liquid level switch; Simultaneously, start the spiral transferpump 6 of potassium hydride KH synchronously, and to be in a ratio of 0.5～0.6% ratio with the stock oil gross weight potassium hydroxide is sent into methyl mixture additive blending groove 8, and start transferpump 12a in order to carry methyl alcohol, send into methyl mixture additive blending groove 8 synchronously to be in a ratio of 18～20% methyl alcohol with the stock oil gross weight, allow two kinds of additives in methyl mixture additive blending groove 8, mix; Simultaneously, potassium hydroxide and methyl alcohol that startup agitator 81 will be sent in the methyl mixture additive blending groove 8 stir and concoct, and make the methyl mixture.Finish stir and blending after two kinds of methyl mixture additives send in first esterification blending groove 91 with transferpump 12b again and carry out transesterification with vegetable and animals oils, stirrer 911 starts and stirs at a slow speed in the transesterification process, methyl mixture additive mixed solution and vegetable and animals oils and stock oil are mixed but does not produce emulsion.6～12 hours transesterification time; During material in first esterification blending groove 91 carried out transesterification, above-mentioned program continued to carry out, that is the esterification that stock oil and methyl mixture additive are sent into that continues concocts in the groove 92 and carry out transesterification, and the rest may be inferred;

Because its flow of transferpump of the esterification of many groups blending groove (91-96) and coordinating operation can be adjusted, can allow the process of blending material utilize the time difference and form a successional transesterification processing procedure, this continuous processing procedure then can with hour be finish in time of unit an integer batch, for example finished the transesterification processing procedure of 24 tonnes biofuel in 24 hours, the flow of charging discharging pump is then controlled at per hour 1 tonne; Thus, just do not need to allow this transesterification process unit produce the situation that processing procedure is stagnated;

Be temporary in the biofuel mixed solution of esterification blending groove 9 (91-96) after transesterificationization is finished, its upper strata is the biofuel work in-process, and lower floor is the by product of biofuel processing procedure, wherein contains materials such as methyl alcohol, free fatty acids and raw glycerine.At this moment, disc formula separating centrifuge 10 begins to start, and transferpump 12d then begins will to carry out centrifugation in the disc formula of the sending into separating centrifuge 10 that material continues in the 1st to the 6th the esterification blending groove (91-96) in regular turn; The biofuel that proportion is lighter in the process is taken in the position of dish body central authorities in disc formula separating centrifuge 10, pushed then to enter in the pipeline to enter in the clarifixator 11 via control valve 13 and contacted with washing water, washing water then are by in the washing water storage tanks (WTK) 14 and send into clarifixator 11 by recycle pump 12g via control valve 15, process like this, the biofuel that transesterificationization is finished has namely been finished preliminary washing, sends into the washing processing procedure of preparing to carry out biofuel in the biodiesel work in-process blending grooves 22 (seeing also the 3rd figure) again; Simultaneously, the transesterification process by product in the disc formula separating centrifuge 10 then because proportion is heavier pushed to the centrifugal dish body outside side outlet be thrown out of then outside the whizzer, wait for the raw glycerine pretreatment process that enters next stage.

In Ben Chu, using many esterification grooves simultaneously is in order to enhance productivity; For example, when first esterification blending groove 91 is carrying out esterification, opening for feed can be switched, the processing procedure that allows aforementioned preparation, mixing, stirring mix well continues to carry out, and after 6～12 hours, when last esterification blending groove 96 preparation works are finished, just the transesterification of first esterification blending groove 91 is finished, therefore, can start transferpump 12d in order to transesterification in first esterification blending groove 91 is finished the processing procedure that material pumps into next stage; And after the material pumping of first esterification blending groove 91 is finished, material in second esterification blending groove 92 also transesterificationization finish, switching through control valve, this transferpump 12d then transfers the material in second esterification blending of pumping groove 92, by that analogy, form a successional processing procedure.

Seeing also the 3rd figure, is the present invention's biofuel centrifugation and washing process unit synoptic diagram.As shown in the figure: the major equipment of the required usefulness of this unit processing procedure comprises three groups of disc formula separating centrifuges (StackDiscSeparator) 17～19, two groups of

clarifixators

20,21, four biofuel work in-

process blending grooves

22,23,24,29,14, five groups of recycle pump 12g～12k of washing water storage tank (WTK), and other pipe fitting, control valve etc.

During actual job, be admitted among the biofuel work in-process blending groove 22 by aforementioned vegetable and animals oils esterification manufacture procedure and through the biofuel work in-process of preliminary washing, when liquid level arrives the setting liquid level, recycle pump 12f starts, material is sent into disc formula separating centrifuge 17 via control valve 26 to be separated, because biofuel proportion is lighter, therefore being taken the whizzer position intermediate after in quilt in the high speed centrifugation process is pushed out whizzer and is entered in the clarifixator 20 via control valve 27, simultaneously, because the washing water proportion that contains xanthan gum is heavier, is therefore pushed and entered that side outlet is continued to be pushed out to the outside standby of whizzer then outside the disc formula separating centrifuge 17; So far, the washing water of biofuel and preliminary washing are separated, then are transferred via control valve 28 through the biofuel of washing for the second time and enter biofuel work in-process blending groove 23, and washing processing procedure is for the third time carried out in preparation.By that analogy, this kind washing processing procedure has three times, in order to the natural glue in the biofuel is separated via the washing processing procedure.

In the present invention, biofuel and water carried out tight to contact in order to wash the equipment that comes unstuck be a kind of clarifixator 11 centrifugal and that high speed shear is parallel that uses, 20,21, in the washing process, clarifixator uses principle centrifugal and that high speed shear is parallel, the molecule of biofuel is trimmed to size near 5 μ (5/1000mm), so that can fill part with the water molecules of washing water contacts, reach the purpose of washing, finish the biofuel of contact and washing, the mixture of water and natural glue is then sent into next disc formula whizzer again and is carried out liquid/liquid separation, biofuel that proportion is lighter is sent into clarifixator and is carried out next one washing processing procedure again, and the rest may be inferred.Because water and the proportion big (about 1.0) that attaches to the natural glue of water molecules, and its proportion of the molecule of biofuel less (between 0.82～0.90), therefore water and the natural glue (xanthan gum) that attaches to water molecules are got rid of to the outer rim of the dish body of separating centrifuge, biofuel is then taken in the middle layer in the dish body, owing to the result of continuous charging, form the continuous process of a continuously feeding and discharging; The biofuel of finishing washing is then sent into next processing procedure and is carried out drying.

The present invention is the water resources that avoids waste, and can use different biofuel work in-process blending grooves will wash washing water packing classification later for utilizing again; For example washing for the second time used washing water can utilize the washing water that wash usefulness as next batch for the first time again, and the used washing water of washing institute can reuse the washing water use of washing usefulness as next batch for the second time for the third time, and the rest may be inferred.For the first time the used washing water of institute and reusable recovery washing water then enter the waste water treatment plant and carry out wastewater treatment.

Seeing also the 4th figure, is biofuel drying process cell schematics of the present invention.As shown in the figure: this unit processing procedure need with major equipment comprise a biofuel temporary tank 24 (in the 3rd figure), one group of preheater 2b, one thermal oil expansion slot 4b, one cluster film distiller 30, a plate-type heat exchanger 31, one group of biofuel finished product temporary tank 33, one group of waste water temporary tank 34, one group of gas-liquid separator 35, one group of vacuum pump 36, one group of thermal oil recycle pump 120, one transferpump 121, one group of heat transfer oil heater 37, one group of cooling tower 32, two groups of cooling water circulating pump 12p and 12q, and pipeline, peripheral equipments such as control valve.

When operation, starting earlier vacuum pump 36 continues thin-film evaporator 30 and the pipeline that is connected thereof and waste water temporary tank 34, biofuel finished product temporary tank 33 to bleed, allow the thin-film evaporator 30 interior pressure of pipeline inner and that be connected be down to till the 50mBar (0.05bar), allow vacuum pump 36 maintain armed state then and when pressure rises to 100mBar (0.1bar), start voluntarily again.

Start cooling tower 32 and cooling water circulating pump 12p or 12q, water coolant is sent into plate-type heat exchanger 31, so that carrying out heat exchange with the water vapour that enters plate-type heat exchanger 31 returns in the cooling tower 32 and dispels the heat, simultaneously, water coolant also must import the axle seal cooling water entrance of thin-film evaporator 30, the axle envelope is cooled off, be back to cooling tower 32 again.

Start thermal oil recycle pump 120, thermal oil is sent into the interlayer of flow through in the circulation line shell-type preheater 2b and thin-film evaporator 30, the thermal oil expansion slot 4b that flows through simultaneously on the other hand returns thermal oil recycle pump 12o and goes into the unbroken circulation of interruption-forming.Then, start heat transfer oil heater 37, allow thermal oil begin heating, allow the thermal oil working temperature be increased to more than 140 ℃.

Startup transferpump 121 is sent into the biofuel in the biofuel work in-process blending groove 24 among the preheater 2b and is carried out indirect heat exchange with thermal oil, allows the biofuel of leaving preheater 2b maintain 95 ℃, enters in thin-film evaporator 30 cylinder bodies again; Though, entering biofuel in thin-film evaporator 30 cylinder bodies is spread to film and is evenly spread upon in thin-film evaporator 30 cylinder bodies, but because the temperature of thermal oil can keep the interior biofuel film of thin-film evaporator 30 cylinder bodies to maintain 95 ℃ working temperature, on the other hand, because the air pressure in thin-film evaporator 30 cylinder bodies maintains 100～150mbar (state of 0.1～0.15bar), moisture content contained in the biofuel is start vaporizer at 95 ℃, the water molecules that is evaporated then follows outlet line and enters in the plate-type heat exchanger 31 and carry out being condensed after the heat exchange with water coolant, enter waste water temporary tank 34 again, and when waste water temporary tank 34 liquid levels arrive preset height, start waste water pump 12m waste water is discharged.

On the other hand, because biofuel does not still reach the distillation point under the operating pressure of 100mBar, therefore fail the biofuel oil film of evaporation and then slide along inboard wall of cylinder block and fall into biofuel finished product temporary tank 33, and finished product transfers to pump 12n to start when liquid level reaches setting point, processed oil is delivered to outside processed oil storage tank district store, wait for and selling.

Above-mentioned is preferred embodiment of the present invention only, is not to limit the scope of the present invention.Be that all equalizations of doing according to the present patent application claim change and modification, be all claim of the present invention and contain.

Claims

1. the process for extracting of a biofuel comprises: mix with the methyl mixture additive after (1) is heated to 55 ℃ with animal-plant oil and carry out transesterification; Wherein, described methyl mixture additive is stirred together and is got by potassium hydroxide and methanol mixed; (2) with disc formula separating centrifuge the biofuel work in-process are separated from the transesterification product, obtained the biofuel work in-process; (3) the work in-process biofuel is carried out repeatedly washing and separating treatment, and then, the work in-process biofuel after will washing is again carried out the film vacuum drying treatment, namely;

Washing required equipment described in the step (3) comprises disc formula separating centrifuge, clarifixator, biofuel work in-process blendings groove, washing water storage tank, recycle pump, and other pipe fitting, control valve;

2. according to the described process for extracting of claim 1, it is characterized in that: the consumption of potassium hydroxide accounts for the animal-plant oil gross weight in the step (1)

The consumption of methyl alcohol accounts for the animal-plant oil gross weight

3. according to the described process for extracting of claim 1, it is characterized in that: in the transesterification process reaction raw materials is stirred, the time of described transesterification is

Hour.

4. according to the described process for extracting of claim 1, it is characterized in that: will finish in the step (2) in the disc formula of the sending into separating machine that the reaction product of transesterificationization continues and carry out centrifugation; The biofuel that this proportion is lighter is taken in the position of whizzer dish body central authorities in whizzer, pushed then to enter in the pipeline to enter in the clarifixator via control valve and contacted with washing water, washing water then are that the saponification glycerol mixture that proportion is heavier then is discharged from whizzer by in the washing water storage tanks and send into clarifixator by transferpump via control valve.

5. according to the described process for extracting of claim 1, it is characterized in that: with clarifixator the molecule of biofuel is trimmed to little size to 5 μ m in the step (3), in order to can fully contact with the water molecules of washing water, the mixture of biofuel, water and the natural glue of finishing contact and washing is then sent into next disc formula whizzer again and is carried out liquid/liquid separation, the biofuel that proportion is lighter is sent into clarifixator and is carried out next one washing processing procedure, by that analogy.

6. according to the described process for extracting of claim 1, it is characterized in that: in the step (3) this biofuel drying process need with equipment comprise biofuel work in-process blending groove, preheater, thin-film evaporator, plate-type heat exchanger, biofuel finished product temporary tank, finished product and transfer to pump, waste water temporary tank, waste water pump, vacuum pump, gas-liquid separator, heat transfer oil heater, thermal oil recycle pump, transferpump, thermal oil expansion slot, cooling tower, cooling water circulating pump, pipeline, control valve.

7. according to the described process for extracting of claim 1, it is characterized in that: the film vacuum drying treatment described in the step (3) is: the biofuel work in-process are sent in the preheater with transferpump carried out indirect heat exchange with thermal oil, allow the biofuel work in-process that leave preheater maintain 95 ℃, enter thin-film evaporator again, entering biofuel in the thin-film evaporator cylinder body is spread to film and is evenly spread upon in the thin-film evaporator cylinder body, contained moisture content is that start vaporizer enters outside heat exchanger and is condensed at 95 ℃ in the biofuel, the biofuel film of failing to be evaporated then slides along the film evaporator inboard wall of cylinder block and falls into biofuel finished product temporary tank, finishes dehydrating processing procedure.