KR102172531B1 - Apparatus for separating and recovering PAO included in POME and, methods thereof - Google Patents

Abstract

The separation and recovery device according to the present invention is a falling thin film evaporation type device having a horizontal multi-pipe structure, and can be implemented in a very compact structure compared to a vertical type, and the unique multi-pipe structure improves the wetting rate to maximize heat transfer performance. It is characterized in that it is possible to separate and recover oils having a high pour point such as palm by-product oil (PAO) through process temperature control.

Description

Device for separating and recovering PAO included in POME, and method thereof {Apparatus for separating and recovering PAO included in POME and, methods thereof}

The present invention relates to a device that evaporates and removes water contained in POME and recovers PAO. More specifically, as a falling thin film evaporation device having a horizontal multi-tube structure, it is implemented in a very compact structure compared to a vertical type. And, due to the unique multi-pipe structure, the wettability is improved to maximize the heat transfer performance, and the process temperature control allows the separation and recovery of oils with a high pour point such as palm by-product oil (PAO). will be.

In addition, the present invention also relates to a PAO recovery method using such an apparatus.

In general, POME (palm oil mill effluent) is produced as a by-product in the production process of CPO (crude palm oil). The process by which POME is made is described in WO 2010/101454 A2 and the like.

POME contains 95% to 97% of water and 3% to 5% of oil (PAO, palm acid oil). Methods for separating and recovering oil such as PAO from high moisture liquid by-products such as POME include a flowing thin film evaporation method in which water is evaporated to remove, a centrifugation method as a physical treatment method, and a chemical treatment method. .

The centrifugal separation method is disadvantageous because of its hardening property at room temperature when the pour point is high and has a problem that it is uneconomical than the flowing thin film evaporation method. In addition, the chemical treatment method has a problem that the process equipment is very complicated and expensive (高價).

In contrast, the falling thin film evaporation method is advantageous because it can utilize waste heat generated from the boiler. 1 shows an example of a conventional flowing thin film evaporation type apparatus, which is disclosed in Korean Patent Application Laid-Open No. 10-2017-0073540.

The device (1) is a vertical evaporation type device in which a pipe (2) is installed vertically, and while the steam supplied from the outside moves upward through the pipe (2), the POME is heated to evaporate water to open the exhaust port (3). It is discharged to the outside through and PAO is discharged through the drain port (4).

However, the apparatus 1 has a problem in that the length of the pipe 2 must be lengthened in order to heat the POME to a high temperature, so that the device becomes too large, and the structure is not suitable for heating the POME to a high temperature.

The present invention has been proposed in order to solve the above-described problems, and has an object to provide a falling thin film evaporation apparatus having a horizontal multi-tube structure that evaporates and removes water contained in POME and recovers PAO.

Another object of the present invention can be implemented in a very compact structure compared to the vertical type, and due to the unique multi-pipe structure, the wettability (wetability) is improved to maximize the heat transfer performance, and the palm by-products through the process temperature control It is to provide a device capable of separating and recovering oil having a high pour point such as oil (PAO).

Another object of the present invention is to provide a PAO recovery method using such a device.

Separation and recovery apparatus 100 and 200 according to the present invention, the frame 10 having a sealed inner space (S); An upper storage tank 30 in which two liquids (first and second liquids) having different vaporization points are mixed and stored; And a plurality of heating units 50 horizontally installed in the inner space S.

The plurality of heating units 50 are installed to form a row with a plurality of layers spaced apart at predetermined intervals. In addition, while the heating fluid moves inside the heating unit 50, the heating unit 50 is heated.

The first and second liquids discharged downward from the upper water storage tank 30 fall into the heating unit 50, but are heated while passing through the plurality of layers sequentially, so that the liquid with a lower evaporation point among the first and second liquids is vaporized. The liquid that is removed and has a high evaporation point moves down to the liquid state and is recovered.

The first and second liquids may be water contained in POME (palm oil mill effluent) and PAO (palm acid oil). POME is generated as a by-product during the production of CPO (crude palm oil). Water is vaporized by the heating unit 50 and discharged to the outside, and PAO moves downward and is recovered.

Preferably, the cross-sectional area of the heating unit 50 decreases from the top to the bottom. In addition, it is preferable that a groove 54 is formed on the surface of the heating unit 50 to improve the wettability of the first and second liquids.

The heating unit 50 is formed by combining a plurality of heat transfer pipes 52 in the transverse direction, and a heating fluid is moved inside the heat transfer pipe 52. The groove 54 is a concave portion formed in a portion where the heat transfer pipes 52 having a circular cross section are connected to each other.

More preferably, the heating unit 50 is made by combining three heat transfer tubes 52 to form an inverted triangle. In this case, the first and second liquids of the upper layer fall into the groove 54 of the lower heating unit 50, and then move laterally along the surface of the heat transfer tube 52 and then move downward.

The heat transfer tube 52 is preferably a metal tube having a high heat transfer rate, for example, a stainless steel tube or a copper tube.

The upper and lower heat transfer pipes 52 are connected to each other by a connection pipe 60. The heating fluid is introduced into the heat transfer tube 52 of the uppermost layer, is sequentially moved to the heat transfer tube 52 of the lower layer, and is discharged from the heat transfer tube 52 of the lowermost layer.

In order to promote water evaporation, it is preferable to maintain a pressure lower than atmospheric pressure in the inner space (S). To this end, a blower 16 may be installed in the exhaust port 12.

The separation and recovery method, which is another aspect of the present invention, is for removing water contained in POME, which is generated as a by-product in the production process of CPO, and recovering PAO. Specifically, the separation and recovery method includes the steps of: (a) discharging the POME accommodated in the upper water storage tank 30 downward; And, (b) After the POME discharged from the upper water storage tank 30 is heated while flowing down the surface of the heating unit 50, it falls to the heating unit 50 of the lower layer, and then, the heating unit of the lower layer. It includes a; step of heating while flowing down the surface of (50).

The heating unit 50 is formed to be elongated in the horizontal direction, and a heating fluid is moved therein. The surface of the heating unit 50 may be maintained at 100 ℃ ~ 200 ℃.

While the POME is sequentially passing through the plurality of layers, it is heated to evaporate and remove the water contained in the POME, and the PAO is recovered by moving downward in a liquid state.

The present invention relates to an apparatus and method for evaporating and removing water contained in POME and recovering PAO, and has the following effects.

First, as a falling thin film evaporation type device having a horizontal multi-pipe structure, it can be implemented in a very compact structure compared to a vertical type.

Second, due to the unique multi-pipe structure, the wetting rate is improved and the heat transfer performance is maximized.

Third, it is possible to separate and recover oils having a high pour point such as palm by-product oil (PAO) through process temperature control.

Fourth, it is efficient because it can respond by increasing or decreasing the layer and heat of the heating unit 50 according to the capacity to be treated and the temperature of the POME.

1 is a cross-sectional view showing a vertical falling thin film evaporation type apparatus according to the prior art.
2 is a block diagram showing a PAO separation and recovery device according to a first embodiment of the present invention, a heating fluid supply source, a POME supply source, and a lower reservoir connected to the device.
Figure 3 is a front cross-sectional view showing a PAO separation and recovery device.
Figure 4 is a side cross-sectional view showing a PAO separation and recovery device.
5 is a perspective view showing a heating unit provided in the separation and recovery device.
6 is a cross-sectional view showing a process in which POME (a mixture of water and PAO) dropped from the upper reservoir is heated by a heating unit.
7 is an enlarged view of portion A of FIG. 6.
Figure 8 is a view showing a side of Figure 6;
9 is a front cross-sectional view showing a PAO separation and recovery device according to a second embodiment of the present invention.
10 is a graph showing the relationship between the inlet temperature of the heat medium oil and the moisture content of the recovered PAO.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventors appropriately explain the concept of terms in order to explain their own invention in the best way. Based on the principle that it can be defined, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only examples of the present invention, and do not represent all the technical spirit of the present invention, and various equivalents that can replace them at the time of application And it should be understood that there may be variations.

The present invention separates water and PAO by using the difference in evaporation point between water and PAO contained in POME, and this technical idea is not only in'water and PAO', but also in'a mixture of two liquid components having a difference in evaporation point'. Can be applied. Therefore, it should be understood that the present invention not only POME, but also'a mixture of two liquid components having a difference in vaporization point' is the scope of the rights. However, in the following description, for convenience of explanation, POME is used as an example.

2 is a block diagram showing a PAO separation and recovery device according to a first embodiment of the present invention, a heating fluid supply source, a POME supply source, and a lower reservoir connected to the device, and FIG. 3 is a front cross-sectional view of the device.

The PAO separation and recovery apparatus 100 according to the present invention includes a frame 10, an upper water storage tank 30, and a plurality of heating units 50 installed under the upper water storage tank 30.

The frame 10 has a sealed inner space (S). An upper water storage tank 30 and a heating unit 50 are installed in the inner space S.

In addition, an exhaust port 12 and an exhaust port 14 are formed in the frame 10.

The exhaust port 12 is installed on the upper portion of the frame 10. Water vapor (steam) produced by evaporation of water is discharged through the exhaust port 12. It is preferable that a blower 16 is installed in the exhaust port 12, which is to promote the vaporization of water by maintaining the pressure of the internal space S lower than atmospheric pressure.

The drain port 14 is installed at the lower end of the frame 10. The liquid PAO is discharged to the lower reservoir 76 through the drain 14. To this end, the lower end of the frame 10 is preferably formed to incline downward toward the drain port 14.

The upper water storage tank 30 is installed on the frame 10. The upper water storage tank 30 receives POME from the POME supply source 74 and stores it therein. Further, a through hole (32 in FIGS. 6 and 8) is formed on the lower surface of the upper water storage tank 30, and POME is discharged downward through the through hole 32 and falls to the heating unit 50. A water level sensor (not shown in the drawing) may be installed in the upper water storage tank 30 to maintain an appropriate POME water level.

The heating unit 50 is installed horizontally under the upper water storage tank 30. In this specification,'horizontal' is used not only to be horizontal in a mathematical sense, but also to include'a case where it is installed to be slightly inclined but is substantially horizontal'.

The heating fluid is moved inside the heating unit 50. After the heating fluid is supplied from the heating fluid supply source 72, for example, a boiler, it heats the heating unit 50 while flowing along the interior of the heating unit 50. It is preferable that the surface of the heating unit 50 is heated to a temperature of 100°C to 200°C by the heating fluid. In this temperature range, water is evaporated and PAO remains in a liquid state when it is approximately atmospheric pressure. Can be separated.

The heating unit 50 may be installed to form a row with a plurality of layers. As shown in FIGS. 3 to 4, the heating unit 50 may form 6 layers and 2 rows, or as shown in FIG. 9, 10 layers and 8 rows. The number of layers and rows may increase or decrease depending on the amount of POME to be treated and the temperature of the supplied POME. For example, if the amount of POME to be treated is large, the number of heat can be increased, and if the temperature of the supplied POME is low, the number of layers can be increased, and if the temperature of the supplied POME is high, the number of layers can be decreased. In this way, the device 100 according to the present invention can flexibly respond to conditions, so it is advantageous and can reduce equipment cost.

The heating unit 50 constituting the upper and lower layers is preferably located on a straight line, and this configuration cooperates with the configuration in which the cross-sectional area of the heating unit 50 decreases from top to bottom, so that the POME of the upper heating unit 50 is It falls in the center of the lower heating unit 50.

The heating unit 50 may be formed by combining a plurality of heat transfer tubes 52 in a transverse direction. The heat transfer tube 52 is a metal tube through which a heating fluid can move (pass), and a metal tube having excellent thermal conductivity, such as a stainless steel tube or a copper tube, may be used as the heat transfer tube 52. In addition, the outer diameter of the heat transfer tube 52 is preferably 10 mm to 30 mm, but is not limited thereto.

Preferably, the heating unit 50 is made by combining the heat transfer tube 52 having a circular cross-section to form an inverted triangle, more preferably three heat transfer tubes 52 are combined to form an inverted triangle to form the heating unit 50 Achieve.

When the three heat transfer tubes 52 are combined to form an inverted triangle to form the heating unit 50, as shown in Figs. 6 to 7, the POME separated from the top is heated while moving along the surface of the heat transfer tube 52, It falls in the center of the lower heating unit 50.

In addition, a groove 54 is formed in a portion where the two heat transfer pipes 52 are connected. The groove 54 is formed because the cross section of the heat transfer tube 52 forms a circle, and the groove 54 serves to increase the residence time of the POME. In addition, when the heating unit 50 has an inverted triangular cross-section, the residence time passing through each stage (each layer) increases as compared to a single tube, and accordingly, the flow velocity of the falling POME due to gravity decreases. In addition, in the case of a heat transfer tube having such an inverted triangular cross section, a compact system can be implemented compared to a single tube arrangement.

As such, when the POME flows down the side of the heating unit 50, the structure of the heat transfer pipe combined to form an inverted triangle serves to increase the residence time of the POME, and a decrease in flow rate accordingly improves the wetting rate. In the case of falling thin film heat transfer, the increase of the heat transfer area due to the improvement of the residence time and the wettability is directly connected to the improvement of the heat transfer performance.

The heating fluid may be exhaust gas discharged from the boiler, heat medium oil, or the like, but is not limited thereto. When boiler exhaust gas is used as a heating fluid, it is economical and eco-friendly, so it is advantageous. According to the present invention, in the case of oil having a high pour point, fluidity can be secured by using high-temperature exhaust gas or heat medium oil, so that the oil can be separated and recovered.

The upper and lower heating units 50 are connected to each other by a connecting pipe (60 in FIG. 4). Accordingly, as shown in FIGS. 2 and 4, the exhaust gas supplied from the boiler 72 (heating fluid supply source) is supplied to the uppermost heating unit 50 and then sequentially passed through the lower heating unit 50. Then, it is discharged from the lowermost heating unit 50. For reference, arrows in FIG. 4 indicate the moving direction of the heating fluid.

It is advantageous that the exhaust gas (heating fluid) supplied from the boiler 72 is supplied to the uppermost heating unit 50 because the POME in a low temperature state is heated when the exhaust gas is in a high temperature state.

9 is a front cross-sectional view showing a PAO separation and recovery device according to a second embodiment of the present invention. Among the reference numerals of FIG. 9, the same elements as those of FIGS. 1 to 8 denote the same elements.

As shown in Fig. 9, in the apparatus 200, the heating units 50 are arranged in 10 layers and 8 rows. As described above, the number of layers and rows may be determined in consideration of the amount of POME to be treated and the initial temperature of the POME (the temperature of the POME accommodated in the upper storage tank).

On the other hand, FIG. 10 shows the inlet temperature of the heat medium oil (the temperature of the heat medium oil flowing into the uppermost heating unit) and It shows the relationship between the moisture content (wt%) of the recovered PAO.

As shown in Fig. 10, the higher the inlet temperature of the heating medium oil, the lower the moisture content (wt%) of the recovered PAO. When the inlet temperature is 190°C, the moisture content is 8.7%, which is less than 10%, so it is suitable as a liquid fuel for power generation. Do.

Then, a method of recovering PAO from POME using the apparatus 100 and 200 will be described below.

First, POME is supplied from the POME supply source 74 to the upper water storage tank 30. The POME source 74 may be a pond (or reservoir) containing the POME, but may also be a tank that stores the POME.

Then, the heating fluid is supplied to the heating unit 50 from the heating fluid supply source 72. For example, the exhaust gas of the boiler is supplied to the heating unit 50. The heating fluid is supplied to the heating unit 50 of the uppermost layer.

POME accommodated in the upper water storage tank 30, as shown in Figs. 6 to 8, is discharged downward through the through hole 32, falls to the heating unit 50 of the top layer, and fell to the heating unit 50 of the top layer. Is heated by the heating unit 50 while flowing down the surface of the heating unit 50 and then falls to the heating unit 50 of the lower layer, and the POME dropped to the heating unit 50 of the lower layer is the heating unit 50 ) Is heated by the heating unit 50 while flowing down the surface. While repeating this process, the temperature of POME rises above the vaporization point of water, and accordingly, the water vaporizes and becomes vapor. The steam is discharged to the outside through the exhaust port 12. At this time, the blower 16 makes the internal space a pressure lower than atmospheric pressure by forcibly exhausting the air in the internal space through the exhaust port 12.

POA occupies most of the liquid separated from the lowermost heating unit 50 and the moisture content is low, and this PAO is discharged to the lower storage tank 76 through the drain hole 14.

1: vertical thin film flow evaporation recovery device 2: pipe
3, 12: exhaust port 4, 14: drain port
10: frame 16: blower
30: upper reservoir 32: through hole
50: heating unit 52: heat transfer tube
54: groove 60: connector
72: heating fluid supply source 74: POME supply source
76: lower reservoir 100, 200: separation and recovery device
S: Inner space of frame

Claims (12)

A frame having an enclosed inner space;
An upper storage tank in which the first and second liquids are mixed and stored; And,
Includes; a plurality of heating units horizontally installed in the inner space,
A plurality of heating units are installed to form a row with a plurality of layers spaced apart at a predetermined interval,
Heating the heating unit while the heating fluid moves inside the heating unit,
The first and second liquids discharged downward from the upper water storage tank fall to the heating unit, but are heated while passing through the plurality of layers sequentially, so that the liquid with a low vaporization point among the first and second liquids is vaporized and removed, and the liquid with a high vaporization point Is recovered by moving down to the liquid state,
Liquids 1 and 2 are water and PAO contained in POME, and POME is generated as a by-product in the production process of CPO.
Separation and recovery device, characterized in that the water is vaporized by the heating unit and discharged to the outside, and the PAO is moved downward and recovered. delete The method of claim 1,
The heating unit is characterized in that the cross-sectional area decreases from the top to the bottom thereof, and a groove 54 is formed on the surface of the heating unit so that wettability of the first and second liquids can be improved. The method of claim 3,
The heating unit is a separation and recovery device, characterized in that a plurality of heat transfer tubes are combined in a transverse direction, and a heating fluid is moved inside the heat transfer tube, and a concave portion to which the heat transfer tubes are connected to each other forms a groove 54. The method of claim 4,
The heating unit is a separation and recovery device, characterized in that the three heat transfer tubes are combined to form an inverted triangle. The method of claim 4,
Separation and recovery device, characterized in that the first and second liquids of the upper layer fall into the grooves 54 of the lower layer, and then move laterally along the surface of the heat transfer tube and then move downward. The method of claim 6,
Separation and recovery device, characterized in that the heat transfer tube is a stainless steel tube or a copper tube. The method of claim 4,
Separation and recovery device, characterized in that the upper and lower heat transfer pipes are connected to each other, and the heating fluid flows into the uppermost heat transfer pipe, sequentially moves to the lower heat transfer pipe, and then discharges from the lowermost heat transfer pipe. The method of claim 8,
Separation and recovery device, characterized in that the inner space maintains a pressure lower than atmospheric pressure. As a method for removing water contained in POME, which is generated as a by-product in the production process of CPO, and recovering PAO,
(a) discharging the POME accommodated in the upper water storage tank downward; And,
(b) heating the POME discharged from the upper water storage tank while flowing down the surface of the heating unit, falling to the heating unit of the lower layer, and heating while flowing down the surface of the heating unit of the lower layer; Including,
The heating unit is formed long in the horizontal direction and the heating fluid is moved therein, and the surface of the heating unit is maintained at 100℃ ~ 200℃,
Separation and recovery method, characterized in that the POME is heated while passing through the plurality of layers sequentially, the water contained in the POME is vaporized and removed, and the PAO is recovered by moving downward in a liquid state. The method of claim 10,
The heating unit is a separation and recovery method, characterized in that the cross-sectional area decreases from the top to the bottom, and a groove 54 is formed on the surface of the heating unit so that the wettability of the POME can be improved. The method of claim 10,
The heating unit is made by combining heat transfer pipes in the transverse direction, but the heat transfer pipes of the upper and lower layers are connected to each other, and the heating fluid flows into the heat transfer pipe of the uppermost layer and sequentially moves to the heat transfer pipe of the lower layer, and then discharges from the heat transfer pipe of the lower layer. Separation and recovery method, characterized in that the.

Images