KR102507702B1 - Method for manufacturing bio oil from oils and fats with high free fatty acids - Google Patents

Abstract

A method for producing bio-oil from high-acid value oil, which can be used as bio-heavy oil and bio-ship oil, is disclosed. A plurality of trays are installed inside the reactor so that a plurality of compartments are formed in a vertical direction inside the reactor, and openings are formed in the plurality of trays to connect upper and lower neighboring compartments, The openings of adjacent stages are crossed with each other, and the raw materials containing glycerin and fatty acids are injected into the raw material inlet located in the middle of the columnar reactor, respectively, and each tray of the reaction zone contains glycerin and fatty acids. Esterification of the raw material to produce glyceride and water, obtaining the produced glyceride through the bottom of the reactor, and the water produced in the esterification reaction is vaporized to a distillation section in the upper part of the reactor in a vapor state moving and separating the active ingredients (reaction raw materials and bio-oil) and water contained in the steam, allowing the separated active ingredients to flow into the reaction zone and removing the separated water in a vapor state through the top of the reactor, The acid value of glyceride is 30 mgKOH/g or less, and the esterification reaction is performed at a reaction temperature of 200 to 250 °C and atmospheric pressure without using a catalyst.

Description

Method for manufacturing bio oil from oils and fats with high free fatty acids}

The present invention relates to a method for producing bio-oil from high-acid value fat and oil, and more particularly, to a method for producing bio-oil that can be used as bio-heavy oil and bio-ship oil from high-acid value fat and oil.

Recently, the main project of bio-heavy oil for power generation started in Korea, and the demand for bio-heavy oil tends to increase steadily. In addition, the demand for low-sulfur oil for ships is expected to increase explosively due to the influence of IMO (International Maritime Organization) 2020, and interest in bio-ship oil is increasing as one of the low-sulfur oils.

The bio-heavy oil for power generation is an alternative fuel to heavy oil (bunker-C oil) manufactured using bio-based oil and fat resources such as animal and vegetable fats and biodiesel process by-products as raw materials, and is currently used as a fuel for heavy oil generators of power generation companies there is. In 2014, a pilot project for bio-heavy oil was started, and after a feasibility assessment, the main project began in 2019.

IMO 2020 is an annex to MARPOL (International Convention for the Prevention of Pollution by Ships) adopted by the International Maritime Organization (IMO), and from January 1, 2020, sulfur oxide environmental (emission) regulations will be enforced. Specifically, sulfur in ship fuel oil Sulfur cap is limited from 3.5% to 0.5%. Accordingly, as one of the measures to reduce sulfur oxide emissions, the demand for the use of low-sulfur marine oil is increasing. In this regard, bio-oil basically has a low sulfur content, so when burned in an internal combustion engine, less sulfur oxides are generated than conventional coal-derived oil.

Since bio-heavy oil or bio-ship fuel oil may cause corrosion of internal devices and equipment if the acid value is high, the acid value of the product must be manufactured below a certain level. For this reason, raw materials of bio-heavy oil or bio-ship fuel oil should use raw materials with a low acid value, and in order to use raw materials with a high acid value, a plan to lower the acid value should be prepared.

Various methods are known for lowering the acid value of fats and oils having a high acid value. As a method of removing free fatty acids in order to lower the acid value of oil in a general oil refining process, there are a method of neutralizing and removing free fatty acids with an aqueous alkali solution and a method of removing free fatty acids by distillation. However, the higher the acid value, the larger the amount of free fatty acid to be removed, and thus the method of removing free fatty acids is less economical. The method of neutralizing with an aqueous alkali solution has a problem in that a large amount of wastewater is generated. In order to use free fatty acids contained in high acid value oil without removing them, a method of converting free fatty acids into bio-oil is proposed.

As a method for producing bio-oil that can be used without removing the free fatty acid of the high acid value oil, one example is to prepare bio-oil (glyceride) by reacting fatty acids with glycerin. At this time, glyceride refers to all mono-, di-, and triglycerides.

The production of bio-oil by reacting fatty acids with glycerin is known as one of the pretreatment methods for using fatty acid-rich oil (maintaining a high acid value) as a raw material for biodiesel (FAME). In general, biodiesel (FAME) is prepared by trans-esterification of bio-oil (glyceride) and methanol (MeOH). At this time, when the fatty acid content of the raw material is high, the amount of the saponification component (soap) produced by the reaction of the fatty acid with the alkali component derived from the reaction catalyst increases, so that the reaction cannot participate and the yield is lowered.

As a solution to this, as shown in Scheme 1 below, as a pretreatment reaction, fatty acids and glycerin are primarily reacted to prepare glycerides, and then the resulting glycerides and methanol are reacted in the presence of a base catalyst 2 Disclosed is a biodiesel production method (trans-esterification) in which biodiesel, fatty acid alkyl ester, is produced by sequentially reacting.

[Scheme 1]

The reaction process of converting fatty acids into bio-oil (glyceride) uses a catalyst or a method of continuously removing water, one of the reaction products, in order to increase reactivity.

US patent US 13/92435 discloses proceeding the reaction in the presence of a solid catalyst. When the reaction is performed using the catalyst, the price of the catalyst used is not only expensive, but also the life of the catalyst is shortened because it is poisoned with impurities or carbon deposition, resulting in high manufacturing cost. In addition, in order to induce a smooth reaction, water is removed by vapor.

1 is a configuration diagram of a batch reactor conventionally used for producing bio-oil, and as shown in FIG. 1 below, one agitator 3 is installed in one reactor 1. It can be seen that in the batch reactor, there is no input and output of reactants and products in the middle of the reaction, but water, which is a by-product produced by the esterification reaction, is continuously removed through the condenser (5).

Chinese Patent Nos. CN 2012-10580909 and CN 2018-10088660 suggest a method for facilitating moisture removal by reacting under weak vacuum/reduced pressure conditions or reacting under nitrogen flow under normal pressure reaction conditions as a non-catalytic reaction. Korean Patent No. KR 10-1073721 discloses a method of reacting under low vacuum/reduced pressure conditions or reacting under nitrogen flow under normal pressure conditions in order to remove water, which is a reaction by-product, in the presence of a catalyst. As such, when using a batch reactor, a device capable of removing water as a by-product is required to increase reactivity. In the case of the batch reaction process, since raw material input time, product discharge time, temperature rise time, etc. are required, compared to the continuous reaction process, the production rate is low, the manufacturing cost is high, and a lot of manpower is required for operation.

A continuous reaction process is proposed to solve the problems of the batch reaction process and to increase the yield and process efficiency. Figure 2 is a view of a continuous flow stirred tank reactor (Continuous Stirred Tank Reactor, CSTR), as shown in Figure 2, the reaction raw material is introduced by the pump (2), at this time, by the heating device (4) Heat is applied and introduced into the reactor (6). In the reactor 6, the produced reactant is discharged to the bottom of the reactor, and at this time, it is cooled by a cooler 7 and discharged. In addition, water, a by-product produced by the esterification reaction, is distilled to the top of the reactor, which can be removed through a condenser (8).

In the CSTR reactor, it is difficult to reach the reaction target level with one reactor because reactants are not first-in-first-out. To compensate for this, some patents disclose a continuous reaction by connecting several reactors. In order to reach the target reaction level, Chinese Patent No. CN 2017-10598802 discloses a method of reacting by connecting four Kettle type reactors in series, and US Patent US 13/924235 connects two CSTR reactors to Continuous reaction is disclosed. In this way, when several reactors are connected, continuous reaction is possible by increasing the reactivity compared to a single CSTR reactor.

However, the proposed batch and CSTR reactors have a problem in that reactants and products are lost along with water discharged as steam while water, which is a reaction by-product, is removed in the form of steam.

According to US Patent US 13/92435, water is removed by vapor to send a smooth reaction. However, since the vapor stream contains water, feed stock, and glycerin, a loss is also generated in terms of yield, so the feed stock in the vapor stream removed and glycerin must be separated.

According to Korean Patent No. KR 10-1073721, when reacting 583.9 g of soapstock, 654.68 g of glyceride was recovered, and the total amount of distillation was 58.58 g, including about 3.5 ml of low molecular weight fatty acids. are doing It can be seen that about 0.5% by weight of fatty acid compared to the product was lost as vapor, and about 5.5% by weight of the total amount of distillation was fatty acid.

Unlike column type reactors, stirred reactors (batch reactors, CSTR reactors) have a structure in which reactants and products discharged as steam along with water cannot be recovered in the process of removing water, a by-product of the reaction, and thus loss of major materials during the reaction process. this happens Since only water cannot be efficiently removed without loss of reactants and products, it is not free from moisture content in raw materials. In addition, since it is difficult to complete first-in-first-out in an agitated reactor, there are cases in which reaction raw materials in the reactor are discharged without sufficiently participating in the reaction. On the other hand, a column type reactor can secure sufficient reactivity with a single reactor because first-in-first-out is possible.

[Prior art literature]

(Patent Document 1) US Patent US 13/92435

(Patent Document 2) Republic of Korea Patent Registration No. 10-1073721

Accordingly, an object of the present invention is to provide a method for continuously producing bio-oil (glyceride) by reacting fatty acids with glycerin without using a catalyst.

Another object of the present invention is to use a column type reactor to effectively remove water, a by-product, so that a purification process of glycerin as a raw material is not required, and it can be used as a reaction raw material without limiting the water content in glycerin, thereby increasing the reaction efficiency It is to provide a method for producing high and economical bio-oil.

In order to achieve the above object, the present invention has a plurality of trays installed inside the reactor so that a plurality of compartments are formed in the vertical direction inside the reactor, and openings are formed in the plurality of trays, The upper and lower neighboring compartments are connected, but the openings of the adjacent stages are crossed so that each stage of the reaction zone is Esterification of raw materials including glycerin and fatty acids in a tray to produce bio-oil and water, obtaining the bio-oil through the lower part of the reactor, and water generated in the esterification reaction while vaporizing The reaction raw material and bio-oil, which are active ingredients, are evaporated together and move to the distillation zone at the top of the reactor in a vapor state, and in the distillation zone, the water contained in the steam and the reaction raw material and bio-oil, which are active ingredients, are separated, and the separated effective The components flow into the reaction zone at the bottom of the reactor and the separated water is removed through the top of the reactor in a vapor state, the acid value of the bio-oil is 30 mgKOH / g or less, and the esterification reaction is 170 to 350 ° C. It includes a method for producing bio-oil, which is performed without using a catalyst at a reaction temperature and atmospheric pressure of.

The method for producing bio-oil from high acid value oil according to the present invention continuously produces bio-oil (glyceride) by reacting fatty acids with glycerin without using a catalyst, and effectively removes by-product water by using a column reactor. Therefore, it is possible to increase the reaction efficiency and provide bio-oil economically by not requiring a purification process of glycerin as a raw material and using it as a reaction raw material without limiting the water content in glycerin.

1 is a block diagram of a batch reactor used in the production of conventional bio-oil.
2 is a view showing a CSTR reactor used in the production of conventional bio-oil.
3 is an overall configuration diagram of a columnar reactor used for producing bio-oil according to an embodiment of the present invention.
4 is a detailed view of a columnar reactor according to an embodiment of the present invention.
5 is a chart showing the acid value according to the internal temperature of the reactor and the residence time according to an embodiment of the present invention.

An embodiment or one aspect of the present invention is illustrated for the purpose of explaining the technical idea of the present invention. The scope of rights according to the present invention is not limited to the embodiments or aspects presented below or specific description thereof.

All technical terms and scientific terms used in the present invention have meanings commonly understood by those of ordinary skill in the art to which the present invention belongs, unless otherwise defined. All terms used in the present invention are selected for the purpose of more clearly describing the present invention and are not selected to limit the scope of rights according to the present invention.

Expressions such as "comprising", "including", "having", etc. used in the present invention are open-ended terms that imply the possibility of including other embodiments, unless otherwise stated in the phrase or sentence in which the expression is included. (open-ended terms).

Expressions such as "consisting only of" a corresponding component used in the present invention should be understood as closed-ended terms excluding the possibility of including other components other than the corresponding component.

Singular expressions described in the present invention may include plural meanings unless otherwise stated, and this applies to singular expressions described in the claims as well.

In one aspect of the present invention, the term "about" is used with the intention of including a slight numerical adjustment that falls within the scope of error in a manufacturing process included in a specific numerical value or the scope of the technical idea of the present invention. For example, the term “about” means a range of ±10%, in one aspect ±5%, and in another aspect ±2% of the value to which it refers. In the context of this disclosure, this level of approximation is adequate unless a value is specifically stated requiring a narrower range.

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail as follows.

3 is an overall configuration diagram of a manufacturing apparatus used in a method for manufacturing bio-oil according to an embodiment of the present invention. As shown in FIG. 3, the reactor used in the present invention is a columnar reactor, and a plurality of trays are installed inside the reactor so that a plurality of compartments are formed in a vertical direction inside the reactor. has been Openings are formed at the plurality of stages to connect upper and lower adjacent compartments, and the openings of the adjacent stages are crossed so as to cross each other. In the bio-oil production method of the present invention, glycerin 10 and raw materials containing fatty acids (10', hereinafter, simply referred to as fatty acids, if necessary) are introduced into the raw material inlet located in the middle of the columnar reactor, respectively, Esterification of glycerin and fatty acids in each tray of the reaction zone (13b) located below the raw material inlet of the step to produce bio-oil (glyceride) and water; Obtaining the generated bio-oil (glyceride) through the lower part of the reactor; And in the step of producing bio-oil (glyceride) and water, while the water produced as a by-product is vaporized, a part of the reaction raw material and product, which are active ingredients, are evaporated together and moved to the distillation section at the top of the reactor in a vapor state, and the distillation section Separating water and active ingredients (reaction raw materials and products) contained in the steam in the step of allowing the separated active ingredients to flow into the reaction zone at the bottom of the reactor and removing the separated water in the form of steam through the top of the reactor; . The bio-oil (glyceride) is produced by an esterification reaction at a reaction temperature of 170 to 350 ° C. under normal pressure without using a catalyst for 2 hours or more, and has an acid value of 30 mgKOH / g or less (bio-oil (glyceride) ) can be produced.

In the present invention, the glycerin 10 includes purified glycerin, crude glycerin, etc., specifically, the concentration of glycerin is 3 to 100% by mass, preferably 5 to 99% by mass, more specifically may contain a variety of glycerin, ranging from crude glycerin having a concentration of glycerin of 5 to 85% by mass to purified glycerin of 99 to 100% by mass. In addition, crude glycerin generated in a traditional fatty acid manufacturing process or biodiesel manufacturing process can be used immediately without additional concentration process, and is preferably used in a liquid state.

The fatty acid-containing raw material 10' has a fatty acid content of 15 to 100% by weight, preferably 20 to 97% by weight.

Specifically, the raw material containing the fatty acid includes acid oil produced by processing soap stock, and the soap stock is alkali added in the process of refining vegetable oil. It is a soap substance produced by the reaction of free fatty acids with acid oil, which is produced by treating soap stock with sulfuric acid.

The raw material containing the fatty acid includes a raw material containing a fatty acid component among products or by-products (eg, fatty acid pitch) generated in an oleochemical process. The oleochemical refers to animal/vegetable oils or chemical products derived therefrom, and the raw material containing fatty acids is a by-product or product generated when the oleochemical is manufactured, and the content of the fatty acid is It is preferably 15 to 100% by weight.

In addition, the raw material containing the fatty acid is animal / vegetable oil milking, oil containing fatty acids from the refining process (eg, palm sludge oil, palm oil mill effluent, palm fatty acid distillate, etc.), recovered oil (eg, , waste cooking oil, brown grease, etc.) and the like, and specifically, animal and vegetable oils having a fatty acid content of 15 to 100% by weight are preferred.

The raw material containing the fatty acid is preferably added in a heated state by the heater 12 before being introduced into the reactor. At this time, the temperature of the heater 12 is 100 to 250 ° C., preferably 150 to 250 ° C. The acid value of the fatty acid is greater than 30 mgKOH / g (high acid value), and is preferably used in a liquid state. By heating the reaction raw material and putting it into the reactor, the internal temperature of the reactor may be kept constant. At this time, since the input amount of fatty acid is relatively larger than that of glycerin, when adding the fatty acid, it may be added by heating.

The mixing ratio (molar ratio) of the fatty acid-containing raw material and glycerin is, specifically, the molar ratio of the fatty acid contained in the fatty acid-containing raw material and the glycerin contained in the glycerin, 3: 0.5 to 3: 2, preferably , 3: 0.75 to 3: 1, if glycerol less than the mixing ratio (molar ratio) of the fatty acid and glycerin is used, the target acid value cannot be satisfied, and if more glycerin is used than the mixing ratio (molar ratio) of the fatty acid and glycerin, the final There is a large amount of unreacted glycerin in the product. In particular, when an excessive amount of glycerin is added, since the prepared bio-oil (glyceride) and glycerin are layer-separated, a process of separating glycerin may be additionally required.

On the other hand, bio-oil having a low acid value can be obtained by using high acid value oil as a raw material through the method for producing bio-oil according to the present invention. The number of days of maintenance with an acid value of greater than g, greater than 60 mgKOH/g, greater than 70 mgKOH/g, greater than 80 mgKOH/g, greater than 90 mgKOH/g, greater than 100 mgKOH/g, greater than 110 mgKOH/g, greater than 120 mgKOH/g, or greater than 130 mgKOH/g And, in particular, it may be an ultra-high acid value of more than 130 mgKOH / g, more than 150 mgKOH / g, or more than 180 mgKOH / g.

According to a specific embodiment of the present invention, through the bio-oil manufacturing method of the present invention, palm oil (PAO) having an acid value of 139 mgKOH/g or palm fatty acid distillate (PFAD) having an acid value of 189 mgKOH/g is used as a fat and oil raw material. Bio-oil with a low acid value reaching 22 mgKOH/g or 26.2 mgKOH/g was obtained depending on the residence time of the reactor.

Hereinafter, the reaction (manufacturing) conditions of the bio-oil (glyceride) according to the present invention will be described in detail. In the present invention, prior to carrying out the continuous reaction in a column type reactor, the reaction conditions were selected as an efficient batch reaction for optimizing the reaction conditions. Specifically, since the esterification reaction according to the present invention is performed in a high temperature region, a high reaction rate and conversion rate of fatty acids can be obtained. The esterification reaction temperature is 170 to 350 ° C, preferably 200 to 250 ° C, the reaction pressure is at normal pressure, and the reaction rate and conversion rate are high even under reduced pressure conditions. If the reaction temperature is out of the range, the reaction rate and conversion efficiency of fatty acids are lowered, or water generated by esterification of fatty acids and glycerin is not smoothly removed, so there is a risk of reverse reaction.

In the present invention, it is preferable to proceed with a non-catalytic reaction, and when a catalyst is used, the reactivity may be better, but the reactivity can be sufficiently increased by effectively removing water as a by-product without using a catalyst. In the case of a catalytic reaction, there is a problem in that the catalyst is difficult to reuse and expensive, so the manufacturing cost is high, and a process (eg, a filter process) for removing the catalyst is additionally required. That is, by not using a catalyst, a process for removing the catalyst is not required and manufacturing cost is lowered, so that bio-oil can be economically produced. In addition, the reaction time of the present invention is 2 hours or more, or 2 hours and 15 minutes or more, and the reaction is completed in about 6 hours. Thus, the reaction time of the present invention may be 2 to 6 hours.

Conventionally, in order to smoothly remove water, which is a by-product of the esterification reaction of fatty acids, it was attempted to increase the reaction conversion rate by reacting under vacuum / reduced pressure conditions or by flowing nitrogen. In order to react under these conditions, facilities for vacuum/reduced pressure operation or nitrogen injection must be provided. However, in the present invention, since the reaction is performed at a high temperature of 170 to 350° C., preferably 200 to 250° C., under atmospheric pressure, water generated in the reaction is continuously removed from the reaction system without any additional equipment. Therefore, the esterification reaction according to the present invention has the advantage of excellent reaction conversion rate to the extent that it is close to a complete reaction beyond the reaction equilibrium without additional equipment.

The bio-oil 18 obtained in the present invention means mono-, di-, triglycerides and mixtures thereof. The target acid value of the bio-oil (glyceride) is different depending on the use of the product, but is 30 mgKOH/g or less, preferably 25 mgKOH/g or less.

4 is a detailed view of a column type reactor for producing bio-oil according to the present invention. As shown in FIG. 4, the esterification reactor used in the present invention is a column type operated under normal pressure conditions. is a reactor In the columnar reactor, a plurality of trays 14a are installed inside the reactor so that a plurality of compartments are formed in a vertical direction inside the reactor, and openings are formed in the plurality of stages. , The upper and lower neighboring compartments are communicated, but the openings of the adjacent stages are formed to cross each other so that the reactants pass through all of the plurality of compartments sequentially.

Inside the columnar reactor, the upper part is referred to as the reactor upper part 13a and the lower part is referred to as the reactor lower part 13b based on the place where the reaction raw material is injected, and the upper part of the reactor is a distillation zone and the lower part of the reactor is a reaction zone. The reaction zone is a full liquid type filled with liquid reaction raw materials and bio-oil as a product. In such a columnar reactor, when glycerin and fatty acid are respectively injected into the raw material inlet located in the middle of the reactor, in the process of being transferred to the bottom of the reactor, the reaction zone 13b is sequentially moved to different trays 14a By doing so, the esterification reaction is continuously performed, short pass of reactants is prevented, first-in first-out is possible, and sufficient reaction time can be secured.

In each tray of the reaction zone, glycerin and fatty acids are esterified to produce bio-oil (glyceride) and water. Among them, water (17) produced as a by-product is vaporized by a high reaction temperature Various types of vapor movement passages according to the type of stage, such as holes, valves, or bubble caps formed in each tray of the reaction zone in a vapor state Passing through (14b), it moves to the distillation zone (13b) at the top of the column type reactor. As water vaporizes and moves to the distillation section at the top of the reactor in a vapor state, it drags the active ingredients, the reaction raw material and bio-oil together, so the vapor components that move to the top of the reactor include water to be removed and effective to be removed. Ingredients (reactants and bio-oil) co-exist.

The distillation zone at the top of the reactor has the same structure as the distillation tower consisting of trays in general chemical processes, and the steam exiting the reaction zone has a high boiling point due to gas-liquid contact in each tray of the distillation zone. The reaction raw material and bio-oil are condensed into a liquid phase, and water with a low boiling point is separated into a gas phase. The separated reaction raw material and bio-oil flow along the tray to the reaction zone at the bottom of the reactor, and water is discharged to the top of the reactor in the form of steam. At this time, water in the form of steam discharged from the top of the reactor is cooled by a condenser, and some is refluxed and returned to the reactor, and some is removed. If water cooled in the condenser and a small amount of active ingredient are refluxed to the reactor, the separation efficiency of water and active ingredient (reaction material and bio-oil) in the distillation zone can be increased.

In the esterification reaction conditions, the water produced by the reaction is removed in the form of vapor, and only the produced bio-oil flows to the bottom of the reactor along the column tray, so the tray of the column type reactor bottom 13b Since there is almost no water, the reaction can be completed without reverse reaction, and the loss of active ingredients can be minimized by returning active ingredients that may be lost as steam from the distillation zone of the reactor to the reaction zone.

A plurality of trays are included inside the columnar reactor, and each tray 14a includes a plurality of vapor passages 14b. At this time, various types such as a bubble cap type, a sieve type, and a valve type may be applied to the vapor movement passage depending on the type of the tray.

In the present invention, bio-oil produced by the esterification reaction of glycerin (10) and fatty acid (10') and glycerin (10) and fatty acid (10'), which are unreacted raw materials, are discharged (15a) to the lower part of the reactor, specifically is cooled by a cooler (16) to obtain bio-oil (glyceride, 18) as a product and glycerin and fatty acids as unreacted raw materials. In addition, each tray prevents short pass of unreacted glycerin (10) and fatty acid (10') and enables first-in first-out, so sufficient retention It guarantees time and improves reaction conversion efficiency. These advantages can form optimal reaction conditions for producing bio-oil with a low acid value.

At this time, in the reaction zone, the flow rate is determined so as to secure a residence time of 2 to 6 hours required for the reaction.

By using a column type reactor, fatty acid and glycerin are esterified to produce low acid value bio-oil (glyceride) reaching a target acid value in only one step.

In addition, it is possible to minimize the amount of fatty acid and glycerin, which are reaction raw materials, and bio-oil (glyceride), which is a product, which are lost as steam exits the reactor together with water, and only water can be efficiently removed. Since it has a reactor structure that can efficiently remove only water, it is possible to use the reaction raw material without restrictions according to the water content. The bio-oil (glyceride) prepared in this way can be used as a substitute for bunker-c oil, such as marine oil and industrial oil, as well as bio-heavy oil.

In a specific embodiment of the present invention, when the continuous reaction column reactor of the present invention is used, the loss rate of glycerides and fatty acids is lower than when using the conventional continuous reaction CSTR reactor, and even if the reaction proceeds at a low temperature It was confirmed that bio-oil having a lower acid value could be obtained (Experimental Example 15).

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. The following examples are intended to explain the present invention in more detail, and the scope of the present invention is not limited by these examples.

analysis method

(1) Acid value (mgKOH / g) was analyzed by KSM ISO 6618 ~ indicator titration method.

(2) Moisture was analyzed using Karl-fisher.

(3) The glycerin concentration of the reaction product was analyzed using KSM 2708-6.7.

(4) The contents of glycerin and oil were quantitatively analyzed using a calibration curve prepared with a KSM 2412 reference (modified) internal standard material. The glycerin internal standard was butanetriol, and the Mono-, Di-, and Triglyceride internal standards were measured using tricaprine to measure the contents of Glycerin, Monoglyceride (Olein, Palmitin), Diglyceride, and Triglyceride (Oil content = Mono- , Di-, Tri-glyceride content sum).

(5) The content of fatty acids was analyzed by GC analysis (Internal standard: C17 acid).

reaction raw material

Raw materials containing fatty acids:

(1) Palm Sludge Oil or Palm Oil Mill Effluent (POME), also called Palm Acid Oil (PAO).

(2) Palm Fatty Acid Distillate (PFAD), a by-product generated during the palm oil manufacturing process.

Purified glycerin: Reagent grade glycerin with a purity of 99% or higher.

Crude glycerin: Glycerin generated from the Oleochemical process (biodiesel, fatty acid manufacturing process, etc.), and the purity of glycerin is low.

[Experimental Examples 1 to 4] Bio-oil production experiment (batch type) according to the reaction temperature .

As an experiment for setting operating conditions in a batch reaction, fatty acid raw materials (PAO) and glycerin (refined glycerin or crude glycerin) were used as reaction raw materials. The acid value, oil (glyceride), moisture, and fatty acid content of the used fatty acid raw material (PAO) are shown in Table 1 below. As the glycerin, various glycerols having a purity of 9 to 99% by weight or more and having different glycerin contents were used. In Experimental Example 1, purified glycerin was used, and in Experimental Examples 2 to 4, crude glycerin was used. The content of glycerin used in the reaction is shown in Table 1 below.

200 g of a raw material (PAO) containing fatty acids and an amount of glycerin having a molar ratio of fatty acids and glycerin of 3:2 were introduced into the reactor, and the reactor temperature was raised to 170 to 250 ° C. The reaction time was calculated from when the reaction temperature was reached . At this time, water (vapor state), which is a reaction product, was continuously removed by cooling to the top of the reactor. Due to the reaction temperature, the final acid value of the finally obtained bio-oil (glyceride) is shown in Table 1 below.

temperature
[℃] Feed CGL Glycerin Content reaction time final acid value
[mgKOH/g] PAO - - - 154.7 Experimental Example 1 250 more than 99% 2hr 1.71 Experimental Example 2 250 35% 2hr 5.26 Experimental Example 3 200 9% 2hr 30.0 Experimental Example 4 170 35% 2hr 73.4

As shown in Table 1, in Experimental Examples 1 to 4, it was confirmed that fatty acids were converted to glycerides at a reaction temperature of 170 to 250 ° C, and the acid value was lowered. In particular, it was confirmed that Experimental Examples 1 to 3 had a reaction temperature of 200 to 250 ° C., good reactivity, and an acid value lower than 30 mgKOH / g after the reaction. On the other hand, in the case of Experimental Example 4, the final acid value did not satisfy the acid value according to the present invention.

[Experimental Examples 5 to 9] Bio-oil production experiment (batch) according to reaction time .

A fatty acid raw material (PAO) and crude glycerin having a purity of 8.8% by weight were used as reaction raw materials. The acid value, oil (glyceride), moisture, and fatty acid content of the fatty acid raw material (PAO) used are shown in Table 2 below.

200 g of fatty acid raw material (PAO) and crude glycerin (9% by weight) having a molar ratio of fatty acid: glycerin of 3: 2 were introduced into the reactor, and the reaction temperature was raised to 200 ° C. while stirring to reach the above temperature Sampling by time was analyzed. Water (vapor state), a reaction product, was cooled and continuously removed from the top of the reactor. Due to the reaction time, the final acid value, content, moisture, etc. of the finally obtained bio-oil (glyceride) are shown in Table 2 below.

reaction time final acid value
[mgKOH/g] Glycerin
[weight%] Oil
[weight%] moisture
[weight%] FFA
[weight%] PAO - 154.7 0 23.02 1.402 75.03 Experimental Example 5 0hr 141.2 1.4 35.46 - 68.46 Experimental Example 6 1hr 86.5 3.34 56.5 0.567 41.95 Experimental Example 7 1hr 45min 47.6 4.61 71.48 0.444 23.08 Experimental Example 8 2hr 15min 30.0 5.15 79.76 0.45 14.53 Experimental Example 9 2hr 30min 21.8 5.31 84.13 0.28 10.59

As shown in Table 2, Experimental Examples 5 to 7 confirmed that the acid value rapidly decreased from the reaction temperature of 200 ° C to the reaction time of 1 hour and 45 minutes, but did not reach the acid value of 30 mgKOH / g. On the other hand, Experimental Example 8 reached an acid value of 30 mgKOH / g with a reaction time of 2 hours and 15 minutes, and Experimental Example 9 reached an acid value of 21.8 mgKOH / g with a reaction time of 2 hours and 30 minutes and an acid value of 30 mgKOH / g or less. Therefore, it was confirmed that the reaction time was 2 hours or more.

[Experimental Examples 10 to 14] Bio-oil production experiment (batch) according to the mixing ratio (molar ratio) of fatty acid and glycerin .

PAO and crude glycerin having a purity of 35% by weight were used as reaction raw materials. The acid value, oil (glyceride), moisture, and fatty acid content of the PAO used are shown in Table 3 below. 200 g of PAO and crude glycerin were charged into the reactor. At this time, the amount of crude glycerin, which is a reaction raw material, was added according to the molar ratio shown in Table 3 below.

The reaction temperature was set to 250 ° C and raised, and in the case of Experimental Example 11, the reaction temperature was raised to 200 ° C. The reaction time was calculated after reaching the reaction temperature.

FFA:Glycerin molar ratio temperature
[℃] reaction time
[hr] final acid value
[mgKOH/g] Glycerin
[weight%] Oil
[weight%] moisture
[weight%] FFA
[weight%] PAO - 154.7 0 23.02 1.402 75.0 Experimental Example 10 3:2 250 2.5 2.82 4.03 88.31 0.26 1.4 Experimental Example 11 3: 1.5 200 3.5 10.64 3.16 89.58 0.396 5.2 Experimental Example 12 3:1 250 5.5 4.50 0.03 97.35 0.17 2.18 Experimental Example 13 3: 0.75 250 4.5 10.49 0.000 96.931 - 5.1 Experimental Example 14 3:0.5 250 3 46.97 0.000 76.535 - 22.8

As shown in Table 3, as a result of the experiment on the molar ratio (mixing ratio) of fatty acids and glycerin, the acid value was lowered to 50 mgKOH / g under all conditions of Experimental Examples 10 to 14, and in particular, Experimental Examples 10 to 13 were It can be seen that when the molar ratio (mixing ratio) was 3:0.75 to 2, the acid value reached 30 mgKOH/g or less.

In the case of Experimental Examples 10 to 12, a small amount of glycerin in the final product was confirmed. If the input amount of glycerin is too large, glycerin is present in the final product, but since the acid value can be easily lowered as more glycerin is added, a step of separating the glycerin present in the final product is additionally required.

[Experimental Example 15] Comparison of bio-oil production using a continuous reaction columnar reactor and a continuous reaction CSTR reactor (raw material PAO).

Bio-oil was prepared using a continuous reaction column reactor and a continuous reaction CSTR reactor, and acid values and loss rates were compared (Table 4 below). The loss ratio (loss rate) of glycerides and fatty acids in Table 4 is calculated by the following Reaction Formula 2, which is the value obtained by dividing the amount of glycerides or fatty acids removed by steam by the amount of bio-oil discharged to the bottom of the reactor it means.

[Scheme 2]

(1) Examples of using a continuous reaction column type reactor

The operating conditions in the batch reaction tested in Experimental Examples 1 to 14 were applied. The reaction temperature was 250 ℃, bio-oil was prepared under normal pressure conditions. A catalyst was not used, and fatty acid raw material PAO (acid value 139mgKOH/g) and crude glycerin (glycerin content 48% by weight) were used as input materials. PAO was introduced into the reactor by heating, and crude glycerin was introduced into the reactor without heating.

FEED flow rate: PAO 13.6 g/min, CGL 1.8 g/min [FFA: Glycerin molar ratio = 3: about 0.8], Prod flow rate: 14.0 g/min, reactor residence time was set to 4.5 hours. The vapor was removed from the top of the reactor. The physical properties of the finally obtained bio-oil (glyceride) are listed in Table 4 below.

(2) Comparative example using a continuous reaction CSTR reactor

The reaction temperature was 250 ℃, bio-oil was prepared under normal pressure conditions. A catalyst was not used, and the input raw materials were fatty acid raw material PAO (acid value 139mgKOH/g) and crude glycerin (CGL, glycerin content 48% by weight) at a molar ratio (mol ratio, mixing ratio) of 3: about 0.8. mixed and used. The mixed reaction raw materials (PAO, CGL) were heated and introduced into the reactor.

Feed flow rate (PAO and CGL mixed input): 9.5 g/min, Prod flow rate 8.6 g/min, and reactor retention time was set to 2 hours. Vapor was removed from the top of the reactor. The physical properties of the finally obtained bio-oil (glyceride) are listed in Table 4 below.

(3) Results

Example (column type reaction) Comparative Example (CSTR reaction) acid value
[mgKOH/g] 22 (staying time 4.5hr) 46.5 (staying time 2hr) 34.6 (staying time 2.25hr) - Loss rate of glycerides & fatty acids (% by weight) 0.2~0.25 2.82

5 is a chart showing the acid value according to the internal temperature of the reactor and the residence time according to the embodiment. In the reaction zone inside the column type reactor used in the examples, the temperature was 140 to 243 ° C from the top to the middle, and the temperature was maintained at 245 ° C from the middle to the bottom. As shown in FIG. 5, as a result of analysis of a sample sampled in the middle of the reaction zone when the retention time of the columnar reactor (Example) was 2.25 hours, the acid value of the bio-oil (glyceride) was 34.6 mgKOH/g. In spite of the temperature range lower than the reaction temperature of 250 ℃, it has an acid value close to 30 mgKOH / g, and when the retention time of the CSTR reactor (comparative example) is 2 hours (reaction temperature is maintained at 250 ℃ during the stay in the reactor ) showed a value lower than the acid value of 46.5 mgKOH/g.

In addition, it can be seen that when the retention time of the column type reactor (Example) is 4.5 hours, the acid value reaches 30 mgKOH/g or less.

Considering that the reaction results under lower temperature conditions in the column type reactor (Example) are similar to or better than the reaction results under high temperature conditions in the CSTR reactor (Comparative Example), the reaction efficiency in the column type reactor (Example) is higher. Confirmed good.

[Experimental Example 16] Production of bio-oil using a continuous reaction column type reactor (raw material PFAD)

Bio-heavy oil was prepared by continuously introducing and reacting reaction raw materials PFAD and crude glycerin in a column type reactor at 250 ° C. and atmospheric pressure without a catalyst. The reaction raw materials used were PFAD (acid value 189mgKOH/g; ultra-high acid value maintained), crude glycerin (glycerin content 36%), and PFAD 12.8g/min, crude (crude) so that the molar ratio of fatty acid (FFA): glycerin was 3: 0.9. ) glycerin was added at 3.3 g/min. PFAD was heated and introduced into the reactor, and crude glycerin was introduced into the reactor without heating.

Water, which is a reaction product, and water contained in crude glycerin were removed as steam from the top of the reactor, and bio-oil (glyceride), unreacted glycerin, and fatty acids were discharged from the bottom of the reactor at 13.3 g/min. At this time, the residence time in the reactor is about 5 hours.

The acid value of the bio-oil produced when the residence time is 5 hours is 26.2 mgKOH/g, and when using the continuous reaction column reactor of the present invention, the acid value is 30 mgKOH even when a raw material with a very high acid value (raw material with a high fatty acid content) is used It was confirmed that bio-oil of / g or less could be produced.

From the above description, those skilled in the art to which the present invention pertains will be able to understand that the present invention can be embodied in other specific forms without changing its technical spirit or essential features. In this regard, the embodiments described above should be understood as illustrative in all respects and not limiting. The scope of the present invention should be construed as including all changes or modifications derived from the meaning and scope of the claims to be described later and equivalent concepts rather than the detailed description above are included in the scope of the present invention.

Claims (13)

A plurality of trays are installed inside the reactor so that a plurality of compartments are formed in a vertical direction inside the reactor, and openings are formed in the plurality of trays to connect upper and lower neighboring compartments, The openings of the two stages cross each other so that raw materials containing glycerin and fatty acids are injected into the raw material inlet located in the middle of the columnar reactor, and each tray of the reaction zone contains glycerin and fatty acids. Esterifying raw materials to produce bio-oil and water;
Obtaining the generated bio-oil through the bottom of the reactor; and
As the water produced in the esterification reaction is vaporized, the reaction raw material and bio-oil, which are active ingredients, are evaporated together and moved to the distillation zone at the top of the reactor in a vapor state, and in each stage of the distillation zone, the water contained in the steam and the effective Separating a reaction raw material and bio-oil, which are components, allowing the separated active ingredient to flow to a reaction zone at the bottom of the reactor and removing the separated water in a vapor state through the top of the reactor; Including,
The acid value of the bio-oil is 30 mgKOH / g or less,
The esterification reaction is carried out at a reaction temperature of 170 to 350 ° C. and atmospheric pressure without using a catalyst, a method for producing bio-oil. The method of claim 1, wherein the water is separated and removed from the distillation zone at the top of the columnar reactor by passing through steam passages formed at each stage. The method of claim 2, wherein the plurality of steam passages formed at each stage are selected from the group consisting of bubble caps, valves, and holes. The method of claim 1, wherein the lower part of the column type reactor is a reaction zone in which glyceride, which is a product produced by esterification of glycerin and fatty acids, is obtained,
The upper part of the columnar reactor is a distillation zone in which water, a by-product produced by esterification, is vaporized and removed in a vapor state. The method of claim 4, wherein the residence time of glycerin and fatty acids in the reaction zone is 2 hours or more. The method of claim 1, wherein the mixing ratio (molar ratio) of the fatty acids and glycerin is 3:0.5 to 3:2. The method of claim 1, wherein the acid value of the raw material containing the fatty acid is greater than 30 mgKOH/g. The method of claim 1, wherein the reaction temperature of the esterification is 170 to 350 ° C. The method of claim 1, wherein the reaction product bio-oil has an acid value of 25 mgKOH/g or less. The method of claim 1, wherein the glycerin has a concentration of 3 to 100% by mass. The method of claim 1, wherein the water, the active ingredient, the reaction raw material, and the bio-oil are separated by a boiling point. According to claim 7, wherein the raw material containing the fatty acid is fatty acid oil (acid oil) prepared from soap stock (soap stock) produced when free fatty acid is removed in the process of refining vegetable oil; Products or by-products generated in the process of animal and vegetable fats and oils or oleochemicals derived therefrom; Oil containing fatty acids derived from animal/vegetable oil extraction or refining; A method for producing bio-oil, which is selected from the group consisting of animal and vegetable fats and oils selected from the group consisting of waste cooking oil, recovered oil such as brown grease, and mixtures thereof, and mixtures thereof. The method for producing bio-oil according to claim 1, wherein the reaction time of the method for producing bio-oil is 2 hours or more.

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