KR101635452B1 - Hollow fiber membrane module and apparatus for gas-liquid mass transfer comprising the same - Google Patents

Abstract

According to the present invention, by omitting the prior art movable facility part and the culture fluid circulating part, high gas-liquid mass transfer can be seen, especially in carbon monoxide fermentation, while lowering the energy requirement. In addition, when the gas-liquid mass transfer device according to the present invention is used, the mono-acid mass transfer rate under abiotic conditions can be remarkably improved as compared with the prior art using PVDF membranes.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hollow fiber membrane module and a gas-

The present invention relates to a hollow fiber membrane module and a gas-liquid mass transfer device including the hollow fiber membrane module.

In general, various strategies adopted to improve the gas-liquid mass transfer rate include increasing the area of the gas-liquid interface, changing the reactor structure in various ways (Munasinghe and Khanal 2010), original impeller design (Ungerman and Heindel 2007) (Kumares and Joshi 2006), a method of changing agitation time and velocity (Birch and Ahmed 1996), and a method using microbubble dispersers (Kaster, Michelsen et al. 1990; Bredwell and Worden 1998; Worden and Bredwell 1998; Bredwell, Srivastava et al. 1999).

Most of these methods increase the interface surface area for mass transfer and increase the power of the volume-to-volume agitator to further increase the bubble cleavage.

However, there is a problem that such a method can not be adopted on a commercial scale due to high energy costs. Furthermore, there is concern that microbes may be damaged due to the high pressure in the incubator (Bredwell, Srivastava et al. 1999).

In order to achieve energy efficient mass transfer, alternative bioreactor structures have been studied for syngas fermentation (Bredwell, Srivastava et al. 1999; Munasinghe and Khanal 2010; Munasinghe and Khanal 2010). In these investigations, the mass transfer efficiency within the reactor was observed through hydrodynamic conditions in the reactor ( k _L a ) by predicting the volumetric mass transfer coefficient.

Among these reactors, continuous stirred tank reactors (CSTR) showed high k _L a values, but they required high impeller rotation rates and consumed large amounts of energy (Bredwell, Srivastava et al. 1999). Higher impeller speeds can efficiently break large bubbles into small bubbles with more favorable surface / volume ratios. Small bubbles additionally have lower rise velocities, so that the contact time with the liquid becomes longer.

Thus, in microbubble dispersion, bubbles that are extremely small and stabilized by surfactants are generated in high shear zones, providing a more energy-efficient way to increase k _L a (Bredwell, Srivastava et al. 1999 ). Although CSTR is currently a widely used reactor, it is basically unsuitable for microbial applications.

It is economically feasible to commercialize syngas fermentation to increase mass transfer between the substrate and the microorganism, but in the case of large reactors, the power-volume ratio of the agitator and the excessive power cost to increase the impeller rotation rate (Bredwell, Srivastava et al. 1999).

Also, the degree of agitation required to provide the necessary gas-liquid mass transfer for microbial growth may damage shear sensitive microorganisms (Chisti 1989).

The CSTR is also limited in performance due to the low biomass concentration at short hydrodynamic residence times and the cell concentration in the incubator being lowered over time as the cells continue to flow out of the culture system during biomass culture As the diameter of the tank increases, the stirring tank often exhibits poor agitation performance because of the multiphase reaction which can cause a significant difference in the reaction rate and selectivity .

To date, Zhao et al. Have used PVDF membranes for gas-phase mass transfer (Zhao, Haddad et al. 2013), which reported k _L a values of 1.36 h ^-1 , It is only at a remarkably low level, and a large improvement is required.

Birch, D. and N. Ahmed (1996). "Gas sparging in vessels agitated by mixed flow impellers." Powder Technology 88: 3-38. Bredwell, M. D., P. Srivastava, et al. (1999). "Reactor design issues for synthesis-gas fermentations." Biotechnology Progress 15 (5): 834-844. Bredwell, M. D. and R. M. Worden (1998). "Mass-Transfer Properties of Microbubbles: 1. Experimental Studies." Biotechnol. Prog. 14: 31-38. Chisti, M. Y. (1989). Airlift Bioreactors, Elsevier Science Publishing Co., Inc. Kaster, J. A., D. L. Michelsen, et al. (1990). "Increased Oxygen Transfer in a Yeast Fermentation Using a Microbubble Dispersion." Applied Biochemistry and Biotechnology 24 (25): 169-484. Kumaresan, T. and J. B. Joshi (2006). "Effect of impeller design on the flow pattern and mixing in stirred tanks." Chemical Engineering Journal 115 (3): 173-193. Munasinghe, P. C. and S. K. Khanal (2010). "Biomass-derived syngas fermentation into biofuels: Opportunities and challenges." Bioresource Technology 101 (13): 5013-5022. Munasinghe, P. C. and S. K. Khanal (2010). "Syngas fermentation to biofuel: Evaluation of carbon monoxide mass transfer coefficient (kLa) in different reactor configurations." Biotechnology Progress 26 (6): 1616-1621. Ungerman, A. J. and T. J. Heindel (2007). "Carbon monoxide mass transfer for syngas fermentation in a stirred tank reactor with dual impeller configurations." Biotechnol. Prog. 23: 613-620. Wang, J. and W. Wan (2009). "Factors influencing fermentative hydrogen production: A review." International Journal of Hydrogen Energy 34 (2): 799-811. Worden, R. M. and M. D. Bredwell (1998). &Quot; Mass-Transfer Properties of Microbubbles. 2. Analysis Using a Dynamic Model "Biotechnol. Prog. 14: 39-46. Zhao, Y., M. Haddad, et al. (2013). "Performance of a Carboxydothermus hydrogenoformans-immobilized membrane reactor for syngas upgrading into hydrogen." International Journal of Hydrogen Energy 38 (5): 2167-2175.

DISCLOSURE OF THE INVENTION The present invention has been made in order to solve the problems of the prior art as described above, and it is an object of the present invention to provide a gas-liquid mass transfer device capable of exhibiting high gas-liquid mass transfer particularly in carbon monoxide fermentation, .

It is another object of the present invention to provide a gas-liquid mass transfer device capable of remarkably improving the carbon monoxide mass transfer rate while omitting a moving part in the prior art using a PVDF membrane, and to provide a simple structure capable of producing microorganisms and producing products Structure hollow fiber bioreactor.

The present invention also provides a gas-liquid mass transfer device capable of increasing the pressure of the headspace in the reactor without any additional moving device for pressurization, thereby ensuring a high saturated dissolved carbon monoxide value even at a low supply pressure.

According to an aspect of the present invention, there is provided a hollow fiber membrane module comprising: (a) a cap having a through-hole; and (b) a plurality of hollow fiber membranes penetrating the through-hole, wherein the first ends of the plurality of hollow fiber membranes are sealed Wherein the hollow fiber membrane module includes a plurality of hollow fiber membranes and a plurality of hollow fiber membranes. The hollow fiber membrane module according to claim 1, do.

According to another aspect of the present invention, there is provided a gas-liquid mass transfer device including the hollow fiber membrane module and the gas-liquid reactor, wherein the gas-liquid reactor includes a gas inlet and a gas outlet, the gas inlet being fitted with the plug, Wherein a portion from the upper end to the first end is located inside the gas-liquid reactor, a discharge pipe is fitted to the intermediate upper end of the gas discharge port, and a portion from the lower end to the second end of the stopper is located outside the gas- Liquid-medium transferring device.

According to another aspect of the present invention, there is provided a method of manufacturing a hollow fiber membrane, comprising: (a) sealing a first end of a plurality of hollow fiber membranes; (b) passing the plurality of hollow fiber membranes through the through- (C) filling the tube with a sealing agent to cover the other end of the plurality of hollow fiber membranes with both opened tubes so as to come into contact with a lower portion of the cap, and (d) And forming an open end in the plurality of hollow fiber membranes by cutting one end portion in a direction perpendicular to the longitudinal direction.

According to various embodiments of the present invention, by omitting the prior art movable facility portion and the culture fluid circulation portion, high gas-liquid mass transfer can be seen, especially in carbon monoxide fermentation, while lowering energy requirements.

When the gas-liquid mass transfer device according to the present invention is used, the monodisperse mass transfer rate can be remarkably improved in the abiotic condition compared with the conventional technology using the PVDF membrane, It can also be used as a membrane bioreactor.

According to another embodiment of the present invention, by increasing the ratio of the amount of exhaust / inflow using a small-diameter discharge pipe without an additional moving device, the saturated saturated dissolved carbon monoxide value can be shown even at a low supply pressure while showing a pressurized environment inside the reactor.

The present invention is particularly applicable to syngas processing facilities, gas-liquid reactors, non-food gasification treatment facilities (e.g., fuel and compound production facilities through sugar fermentation).

1 is a photograph showing a manufacturing process of a hollow fiber membrane module according to an embodiment of the present invention.
2 is a schematic view of a gas-liquid mass transfer device according to an embodiment of the present invention. Where GR is the gas regulator, DPG is the digital pressure gauge, and OVC is the overhead vapor trap.

One aspect of the present invention relates to a hollow fiber membrane module including (a) a cap having a through-hole, and (b) a plurality of hollow fiber membranes penetrating the through-hole.

At this time, the first end of the plurality of hollow fiber membranes is sealed, the outer surface of the portion from the lower end of the plug to the second end of the plurality of hollow fiber membranes is sealed, and the second end of the plurality of hollow fiber membranes is sealed, The end is open.

Generally, a hollow fiber membrane is a porous membrane including a lumen, and has a structure including a longitudinally empty tunnel inside. The term "sealed" at one end means that the outer surface of the membrane is not sealed at all, so that the gas can penetrate through the membrane through the lumen. However, in order to prevent the gas from escaping through the inner tunnel in the longitudinal direction, It means that only the seal is sealed.

According to one embodiment, the hollow fiber membrane module further comprises a tube, which surrounds the portion from the lower end to the second end of the plug, and the portion from the lower end to the second end of the plug has the plurality A space between the hollow fiber membranes and a space between the hollow fiber membranes and the tubes are sealed.

That is, when dividing the upper part of the hollow fiber membrane and the lower part of the hollow fiber membrane passing through the through-hole, the upper end of the upper part is sealed so that the inner tunnel is closed as described above, and the lower part is sealed in the hollow The portion up to the end of the desert is sealed so that the gas can only move through the inner tunnel and the outer surface of the membrane is clogged so that it is not permeated through the membrane through the lumen.

According to another embodiment, examples of the material of the hollow fiber membrane include polyvinylidene difluoride (PVDF), polystyrene (PS), polyethersulfone (PES), polydimethylsiloxane (PDMS), polypropylene (PP) (CHF). ≪ / RTI > Examples of the material of the stopper include silicone rubber, butyl rubber, neoprene rubber, and high nitrile rubber, but are not limited thereto and are limited to materials having low gas permeability. Examples of the material of the tube include, but are not limited to, polyurethane (PU), polytetrafluoroethylene (PTFE), and silicone.

According to another embodiment, the ratio of (the length from the top end of the plug to the first end) / (the length from the bottom end of the plug to the second end) may be from 1 to 20.

If the ratio is less than 1, it is not preferable because the narrow gas exhaustion region may cause the exhaust gas to aggregate again in the liquid and consequently the vapor-liquid mass transfer rate may be greatly deteriorated. If the ratio exceeds 20, The amount of gas discharged without gas-liquid mass transfer is increased due to a change in the material rate of the discharged gas, which may increase the amount of raw gas to be used.

Another aspect of the present invention relates to a gas-liquid mass transfer device including a hollow fiber membrane module and a gas-liquid reactor.

Wherein the hollow fiber membrane module comprises: (a) a cap having a through-hole; (b) a plurality of hollow fiber membranes penetrating the through-hole, wherein a first end of the plurality of hollow fiber membranes is sealed, The hollow fiber membrane module according to any one of the embodiments of the present invention may further include a hollow fiber membrane module according to various embodiments of the present invention. have.

In addition, the gas-liquid reactor includes a gas inlet and a gas outlet, wherein the gas inlet is fitted with the stopper, the portion from the upper end to the first end of the stopper is located inside the gas-liquid reactor, And a portion up to the second end is located outside the gas-liquid reactor.

In the present invention, a gas-liquid reactor refers to a reactor in which a physical or chemical phenomenon involving mass transfer between a gas and a liquid or accompanying physical phenomenon can occur therein, and does not necessarily mean a reactor in which a chemical reaction occurs.

And the second end is connected to the gas supply unit so that the supplied gas moves through the inner end of the hollow fiber membrane into the gas-liquid reactor through the second end, passes through the cavity of the membrane through the inner lumen, .

According to one embodiment, the gas-liquid reactor may further comprise at least one liquid inlet and at least one liquid outlet.

That is, the gas-liquid reactor may include at least one inlet and outlet of the liquid, respectively, so that the gas can be introduced and discharged continuously or intermittently in the middle of the gas being introduced and discharged.

According to another aspect of the present invention, there is provided a method for manufacturing a hollow fiber membrane, comprising the steps of: (a) sealing a first end of a plurality of hollow fiber membranes; (b) passing the plurality of hollow fiber membranes through the through- (B) filling the tube with a sealant so as to cover the other end of the plurality of hollow fiber membranes with the open tube so as to contact the lower portion of the cap, (d) And forming an open end in the plurality of hollow fiber membranes by cutting a portion of the hollow fiber membrane module in a direction perpendicular to the longitudinal direction.

In accordance with another aspect of the invention the gas outlet from the top of the cap is located inside the gas-liquid reactor is a diameter of a round (10 ^-4 to 10 ^-2 mm, preferably 5 ^10-4 to 5 ㅧ ㅧ ^{10- 3} mm, most preferably 10 ^-3 mm) can be used to provide a pressurized environment inside the reactor by increasing the ratio of emissions / inflow without additional moving devices, thereby ensuring a high saturated dissolved carbon monoxide value.

Hereinafter, various aspects and various embodiments of the present invention will be described in detail with reference to the drawings.

The present invention relates to a vapor-liquid mass transfer module including a hollow fiber membrane bundle and a gas-liquid mass transfer device including the vapor-liquid mass transfer module. More particularly, the present invention relates to a vapor-liquid mass transfer device, .

The gas-liquid mass transfer device according to the present invention may have a structure as shown in FIG. 2 without limitation, and in particular, the module including the hollow fiber membrane bundle serving as a gas injecting part may have a structure as shown in FIG.

1, a plurality of hollow fiber membranes forming a bundle are configured to penetrate through a rubber stopper, the hollow fiber membrane at the lower portion of the rubber stopper is left as an open end, The end of the exposed part is composed of a sealed closed end.

As a result, the gas entering the hollow fiber membrane through the open end of the lower portion of the rubber stopper is discharged through the air gap (lumen) of the hollow fiber membrane surface rather than the sealed closed end of the hollow fiber membrane, .

Hereinafter, the present invention will be described in more detail by way of examples and the like, but the scope and content of the present invention can not be construed to be limited or limited by the following examples. In addition, it is apparent that, based on the teachings of the present invention including the following examples, those skilled in the art can easily carry out the present invention in which experimental results are not presented specifically.

Example

Example 1a: Fabrication of hollow fiber module

15 microporous PVDF hollow fiber membranes (0.1 mm, pore size, 1.2 mm OD, 0.7 mm ID, manufactured by ECONITY) were used. The module was manufactured by the method shown in FIG. 1, and the required number of hollow fiber membranes was cut to a desired length, and one end was sealed with a mixed solution of epoxy and hardener (M, ITW, Devcon) (No.1 in FIG. The epoxy and curing agent were thoroughly mixed in equal amounts just prior to use. After joining the hollow fiber membranes to the other side, M was applied to the outside of the hollow fiber membrane bundle so that the gas could not pass through the membrane in the thickness direction, not in the longitudinal direction, thereby completely sealing the outer pores (FIG. Between the upper and lower epoxy treated areas was left for gas permeation. A silicone rubber stopper (No. 3 in Fig. 1) was used as a holder for the hollow fiber membrane bundle. A transparent polyurethane tube (16 mm OD, 12 mm ID, KPC, Korea Pneumatic, South Korea) was used for the role of potting (No. 4 in FIG. 1) to collect the bundle of hollow fiber membranes through the silicone rubber stopper. The bottom polyurethane tube was again filled with M (FIG. 1, No. 5), allowing gas to pass through the lumen of the hollow fiber membrane only. After the M was completely filled, the M in the polyurethane tube was allowed to fully cure for a sufficient time (No. 6 in FIG. 1). The polyurethane tube and the bundle of hollow fiber membranes were cut with a sharp cutter so that the lower end of the hollow fiber membrane was an open end (No. 7 in FIG. 1). The appearance of the open end (No. 8 in FIG. 1) and the appearance of the final hollow fiber module (No. 9 in FIG. 1) were also provided.

At this time, the length of the hollow fiber membrane portion (the portion where the outer surface was not sealed) located between the upper sealed portion and the upper end of the silicon rubber stopper was 195 mm (effective area is As), and the hollow fiber membrane collected inside the polyurethane Was 50 mm in length.

Example 1b: Overall Device Configuration

The overall reactor structure is as shown in FIG. The hollow fiber membrane bioreactor (HFMBR) was immersed in 400 mL deionized water in a 0.5 L (VL) reactor. The inside of the reactor was maintained at the desired temperature (37 DEG C) by continuously circulating water through a jacketed glass shell using a water circulation tank (Jeio Tech., VTRC-620). The reactor port was sealed using a butyl rubber stopper (Bellco Glass, Inc.) to prevent oxygen from passing through the reactor. The top and bottom of the reactor were shut off using a silicon stopper tightly clamped inside the reactor. The gas flow was adjusted using a digital pressure gauge (Cole-Palmer instrument Co., WZ-68935-18) and the correct CO pressure was adjusted. A check valve was installed on the nitrogen line to maintain the flow in one direction. Marprene tubing (Watson-Marlow Pumps Group) was used for gas supply from the cylinder to the reactor. The overhead vapors were collected in a 250 mL Pyrex glass bottle installed outside the reactor. The waste gas was discharged through a stainless steel pipe through the silicon stopper at the top of the reactor, and the waste gas outlet was directly connected to the discharge pipe of the fume hood.

This was the A _s / V _L of the prepared devices was 27.5 m ^-1, membrane permeation rate of the length of the lumen and pass portion (Lu / Ld) is 3.9 (= 195/50), the lumen through the pressure to 37.23 kPa Respectively. As a result, k _L a was measured as 63.72 h ^-1 .

Examples 2 to 6

In Examples 2 to 6, experiments were carried out in the same manner as in Example 1, except that only the luminal penetration pressure was changed to 37.23, 68.94, and 93.76 kPa, respectively. As a result, k _L a was measured as 63.72, 88.56, and 135.72 h ^-1 , respectively.

Examples 7 to 11

Examples 7 to 11 In an experiment was conducted in the same manner as in Example 1 except that for each change in the value of A _s / V _L to 27.5, 45.9, 62.5 m ^-1. As a result, k _L a was measured as 63.72, 102.96, and 155.16 h ^-1 , respectively.

Comparative Example 1

The procedure of Example 1 was followed except that the polyurethane tubing was not added and the hollow fiber membranes were combined and outer sealed, and then cut perpendicularly to the longitudinal direction to form an open end.

As a result, the initial k _L a remained high at 67.2 h ^-1 , but the kLa values of Examples 1 to 11 remained within the range of 3% for at least 72 hours, whereas in Comparative Example 1, the k _L a remained at about 34% and the durability problem in which the k _L a value is decreased is confirmed.

Claims (10)

A hollow fiber membrane module comprising: (a) a cap having a through-hole; (b) a plurality of hollow fiber membranes penetrating the through-
Wherein a first end of the plurality of hollow fiber membranes is sealed,
The outer surface of the portion from the lower end of the cap to the second end of the plurality of hollow fiber membranes is sealed,
Wherein the second ends of the plurality of hollow fiber membranes are open,
Wherein the hollow fiber membrane module further comprises a tube,
The tube surrounds the portion from the lower end to the second end of the stopper
Wherein a portion between the lower end of the cap and the second end portion is sealed between a space between the plurality of hollow fiber membranes and a space between the hollow fiber membrane and the tube. delete The method of claim 1, wherein the material of the hollow fiber membrane is selected from the group consisting of polyvinylidene difluoride (PVDF), polystyrene (PS), polyethersulfone (PES), polydimethylsiloxane (PDMS), polypropylene (PP) CHF);
The material of the plug is selected from silicone rubber, silicone rubber, butyl rubber, neoprene rubber, and high nitrile rubber;
Wherein the material of the tube is selected from the group consisting of polyurethane (PU), polytetrafluoroethylene (PTFE), and silicone. The hollow fiber membrane module according to claim 1, wherein the ratio of the length from the upper end of the plug to the first end / (the length from the lower end of the plug to the second end) is 1 to 20. A vapor-liquid mass transfer device comprising a hollow fiber membrane module and a gas-liquid reactor,
The hollow fiber membrane module includes (a) a cap having a through-hole, (b) a plurality of hollow fiber membranes penetrating the through-hole,
Wherein a first end of the plurality of hollow fiber membranes is sealed,
The outer surface of the portion from the lower end of the cap to the second end of the plurality of hollow fiber membranes is sealed,
The second end of the plurality of hollow fiber membranes is open,
The gas-liquid reactor includes a gas inlet and a gas outlet,
Wherein the gas inlet is fitted with the plug,
A discharge pipe is fitted in the upper end of the cap of the gas discharge port,
Wherein a portion from an upper end of the cap to the first end is located inside the gas-liquid reactor,
Wherein a portion from the lower end to the second end of the cap is located outside the gas-liquid reactor. 6. The gas-liquid mass transfer apparatus according to claim 5, wherein the gas-liquid reactor further comprises at least one liquid inlet and at least one liquid outlet. 7. The hollow fiber membrane module of claim 5 or 6, wherein the hollow fiber membrane module further comprises a tube,
The tube surrounding a portion of the plug from the lower end to the second end,
Wherein a portion between the lower end of the cap and the second end is sealed between the hollow fiber membranes and a space between the hollow fiber membrane and the tube. The method of claim 5 or 6, wherein the material of the hollow fiber membrane is selected from the group consisting of polyvinylidene difluoride (PVDF), polystyrene (PS), polyethersulfone (PES), polydimethylsiloxane (PDMS) Mixed hollow fibers (CHF);
Wherein the material of the cap is selected from silicone rubber, silicone rubber, butyl rubber, neoprene rubber, and high nitrile rubber. The method of claim 5 or 6, wherein the ratio of the length from the upper end of the plug to the first end / (the length from the lower end of the plug to the second end) is 1 to 20 Gas-liquid mass transfer device. (a) sealing a first end of a plurality of hollow fiber membranes,
(b) passing the plurality of hollow fiber membranes through the through-hole of a cap having a through-hole,
(c) placing both open tubes on the other end of the plurality of hollow fiber membranes so as to come into contact with the lower portion of the plug, filling the tube with a sealing agent and curing the same,
(d) cutting the other end of the plurality of hollow fiber membranes perpendicularly to the longitudinal direction to form open ends in the plurality of hollow fiber membranes.

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