JPS6257615A - Inline degassing method for flowing liquid or slurry - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Industrial Application Field of the Invention The present invention relates to an in-line degassing device for a flowing liquid or a flowing slurry.

``Conventional technology'' Chemical treatment is applied to the transport flow that determines various characteristics.

i! to produce a final product or intermediate product that is processed mechanically or by other methods. I
! In the field of T-industry, which performs subsequent process treatments, such process treatments induce and generate by-products containing gases, and entrain air in the transport flow to prevent process treatment or various subsequent process treatments. have undesirable effects on

For example, the wood valve manufacturing process used in papermaking is generally a multi-stage process consisting of a reaction tank to accelerate the reaction, and a vacuum filter to separate reaction products, unreacted products, and unreacted chemicals] A second chemical treatment is performed. Due to their construction, vacuum filters tend to entrain significant amounts of air into their filtrate. This cancer liquid is generally used to dilute the valve slurry when it is transferred to the reaction tank or the vacuum filter. It is estimated that this increase in air or gas will accelerate the reduction in processing efficiency by this amount until the minimum efficiency equilibrium is reached, and therefore the removal of this air will reduce the processing efficiency of the process. This will help increase efficiency and improve the quality characteristics of the final product.

Conventionally, methods for removing air or gas from liquids or slurries as described above include methods using a retention container that allows sufficient residence time to emit mixed air and debris from the liquid or slurry, and methods that use external heating. A method using a container that accelerates the rate of dispersion of scum, and a method that reduces the surface tension of a liquid or slurry by adding various chemicals to promote separation of air or gas are known.

Problems to be Solved by the Invention However, the two-legged conventional system has the following drawbacks:
are doing.

Methods that use a retention container without a degassing mechanism require a large retention container in order to secure the necessary retention time.
Therefore, securing this container requires a large-capacity container, which requires a large amount of cost and space to install the container.

The method of using a vacuum device receiving container involves an increase in investment costs and energy costs due to the resystem that requires an external vacuum pump and its associated equipment.

In the method of performing chemical treatment, not only is the cost of using the chemical extremely high, but the presence of the chemical itself may lead to a decrease in efficiency in continuous processing.

Therefore, the present invention has been made to solve the drawbacks listed in L. It is possible to remove air from liquid or slurry with a simple and small in-line device, and it is also possible to remove air from liquid or slurry using a simple and small in-line device. It is an object of the present invention to provide a device that does not involve mechanical devices or other means, and that does not require mechanically moving parts or energy other than the energy contained in the liquid or slurry to achieve the above [1] goal. This is the purpose.

``Means for solving the problems j A cylindrical body interposed in the middle has a diameter larger than that of the flow path, and a rhombus is arranged inside the square body to circulate the liquid or slurry passing through the cylindrical body.

Furthermore, an exhaust pipe is disposed inside the foot-shaped main body, the one end of which is open toward the downstream side of the central axis of the cylindrical main body, and the other end of which extends outward from the cylindrical main body. This is a technical measure that allows for storage.

``Function 1 Therefore, 1 The in-line deaerator for the flowing liquid or flowing slurry of the present invention first enters into the large-diameter space of the cylindrical body with a flow vertical to the center line of the flow path. This large diameter space reduces fluid flow velocity and reduces fluid pressure.

Next, as the flow liquid or flow slurry passes through the cylindrical body, its flow direction is changed tangentially by the flow, resulting in circular flow. This change in direction results in the creation of a vortex in the continuous downstream flow path. The liquid or slurry passing through the cylindrical body is exposed to a gentle pressure gradient that binds and expands any entrained air or debris. This gas instantly enters the vortex, which is a lower pressure area than the liquid or slurry, flows backward through the vortex, passes through the exhaust pipe, and is released into the outside air.

j' Embodiment 1 Next, an embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

FIG. 1 is a typical example of an application to a pulp manufacturing process and shows that it can also be applied in similar continuous processing systems.

In the figure, ■ indicates the multi-stage unbleached valve cleaning section, 2 indicates the selection and unbleached finished section, 3 indicates the fluorine treatment section and subsequent bleaching section, and 4 indicates the raw material adjustment section for the paper making section and its paper making section. These are the unbleached pulp washing section 1, the selected and unbleached finished section 2,
! A plurality of devices 3 of the present invention are installed in each connection path between the raw processing section, the white section 3, the raw material adjustment section to the paper making section, and the paper making section 4.
5 to 51 are installed.

The pulp fibers accumulated in the tank 5 for discharging the bulb fibers produced by the well-known cooking process are diluted with the filtrate of the filtrate tank 6, which is transferred by the flow path 7. . Although not shown, this discharged water may be guided to several locations during this process.

The slurry consisting of valve and cellulose solution is transferred via knock-8 to a series of vacuum filters 9, 10.11. The slurry transferred to the vacuum filter 9 is further diluted with the liquid discharged from the filtration tank 6 and accumulated in the vacuum filter 9. The discharged liquid falls into the tank 6 by gravity and is circulated from there as described above. /<The pulp discharged from the gyuto filter 9 is led to a receiver box 12 and diluted with the filtrate in a tank 13.

Then, this slurry overflows into the vacuum washing machine 10, accumulates on the drum 10, and then is transferred to the box 14.
is discharged. Furthermore, this pulp is diluted with the filtrate of the tank 15 and flows overflow into the washer 11, and this valve is then diluted with the filtrate of the tank 15. iJI is discharged from lI1 machine 11 to tank 16 at a medium concentration.

Then, the valve is diluted in a tank 16 using the filtrate in a filtrate tank 17, and the receiver is transferred to a box 19 via a screen 18. The pulp overflows the box 19 and flows into the vacuum washer 20, and the filtrate falls by gravity into the filter tank 17 and is circulated as described above. Then, the valve is extracted from the vacuum washer 20 to a storage tank 21 and temporarily stored there.

Further, the pulp is diluted with the filtrate in the silica water tank 22 and transferred via the quartz tank 23. At exit 1-1 of 1 (I! 23), the pulp slurry is further diluted by the ejected liquid of filtrate 4PV22, and the pulp slurry flows into the box 24.The pulp overflowing from the box 24 flows into the vacuum washer n1 machine 25. The vacuum washing P'II a 25 forms a pulp mat on the vacuum drum.The discharged liquid of the low-concentration valve slurry falls by gravity into the filtration tank 22, from which it is ringed as described above.

In addition, the valve / hecum cleaning fi 25 to tank 26
is discharged to. The filtrate in the filtration tank 27 is used to dilute the pulp in the tank 26, and the pulp after diluting is transferred from the tank 26 to the receiving box 28, where it is further diluted with the discharged liquid in the cancer ice tank 27. Then, the pulp slurry overflows from the box 28 and flows into the vacuum washing machine 29. The vacuum washer 29 forms a pulp mat on the vacuum drum.

The filtrate from the low consistency pulp slurry falls by gravity via the vacuum leg to the filtrate 4f427 and is circulated as described above.

Further, the pulp is transferred from the vacuum washer 29 to the storage tank 30.
In any pulp manufacturing industry, there are multiple processing steps similar to those described above.

Furthermore, 11! The filtrate discharged from the water tank 31 is stored 1i
930 is used to dilute the pulp. The pulp slurry is transferred to a receiving box 33 via a cleaner 32. The pulp slurry is further diluted with the mammary fluid in the cancer water tank 31 and transferred to paper machines 41 and 34.

The paper machine 34 discharges a discharged liquid from the pulp slurry into a filtrate tank 31 from which the filtrate is circulated as described above.

As mentioned above, the various liquids produced in the pulp manufacturing process are normally circulated to each processing stage to dilute the pulp, and each successive processing stage usually undergoes acidic and alkaline treatments alternately. As a result of the reduced effectiveness of the vacuum washer, unreacted chemicals brought in from the previous stage will reduce the effectiveness of chemical treatment in the subsequent stages! The first list is clear. Since the effectiveness of a vacuum washer depends on the amount of air and gas contained in the pulp slurry, reducing the air content in the pulp slurry also improves the effectiveness of the vacuum washer, that is, the effectiveness of subsequent processing stages. is obvious.

From this point of view, it is clear that there are many places in the process where devices that can remove air and mixed gases from filtrate and pulp slurry can be effective. These points of advantage are generally indicated at 35 to 51 in FIG. 1 and represent the installation points in the process where the installation of the apparatus of the invention can provide essential advantages.

Figure 2 ↓ Detailed explanation of the device of the present invention 1! In the figure, 60 is a cylindrical body interposed in the middle of the flow path 7 for liquid, slurry, etc. This cylindrical main body 60 has a diameter larger than that of the flow passage 7 to be coupled, and in this embodiment, the diameter is approximately twice that of the flow passage 7 to be coupled, and the upstream and downstream ends are End face ring plates 64 and 65 are provided in series. This end face ring plate 64,65 is the cylindrical body 6
It has an outer diameter equal to the diameter of 0 and an inner diameter equal to the diameter of the flow channel 7 to which the device of the invention is connected. The flanged connecting cylinders 68a and 68 have a diameter equal to that of the flow path 7.
b, the opening at one end is fixed in close contact with the inner diameter of the ring plates 64 and 65 at both ends, and the flange side is fixed to an intermediate part of the flow path 7, so that liquid or slurry is poured into the cylindrical body 60. inflow,
It is designed to be discharged.

The cylindrical main body 60 is thus formed.

When comparing the same length for the flow path 7 to be incorporated,
It has an inherently larger volume. It is recognized from a common art perspective that this condition reduces the longitudinal velocity of the process fluid due to differences in Nikkei requirements.

1: Inside the foot-shaped main body 60, there is arranged a center 67 for circulating the liquid or slurry passing through the cylindrical main body 6o, and further, inside the cylindrical main body, the - end of the cylindrical main body is disposed. It houses an exhaust pipe 66 that opens toward the flow side of the central axis and has the other end extending outside the cylindrical body.

In the seventh embodiment, a plurality of the blades 67 are held and housed by appropriate means between the downstream end ring plate 65 and the holding plate 69. This ring plate 69 is
The chain type 67 has a radius of curvature of about 1-1/4 with respect to the aperture of the flow passage 7 and an inner diameter of about 1/4. It has a length approximately equal to. This center 67 is connected to the r flow side end face ring plate 65 and the ring plate 6.
The chain type 67 is vertically connected between the 6 blades 67 and has an inner end in contact with the inner diameter surface of the downstream end face ring plate 65 and an outer end thereof in contact with the outer diameter surface of the ring plate 69. are folded over to form a venentury at the inner end of the curve.

Further, the L trachea 66 is fixed to the ring plate 69 in a suitable manner, and the exhaust pipe 66 extends through the ring plate 69. That is, the downstream side of the exhaust pipe 66 extends along the downstream connecting cylinder 68b to approximately the center thereof. The other end side of this exhaust pipe 66 includes a 900-manufacturing part 66a and a flanged extension pipe part 66b.
are connected in a suitable manner and pass through the cylindrical body 60 immediately downstream of the upstream end ring plate 64.

Therefore, the liquid or slurry flowing through the flow passage 7 passes through the upstream connecting cylinder 66a and flows into the cylindrical body 60, where the flow velocity is reduced to reduce pressure loss due to piping resistance. The pressure distribution in the longitudinal section of the blade 67 is made uniform. The resistance provided by the piping directs the flow between the vanes 67, 67 at an angle of 900 to the longitudinal axis of the flow channel 7. The pressure decreases due to the Ventury effect caused by the increase in flow rate between fi67 and fi67, and air and gas bubbles mixed in the liquid expand and coalesce.

Then, a thin flow layer is formed in the flow that has passed between each i67 and 67, and larger gas bubbles are formed due to the continuous Venturian action, and the thin flow layer allows air and gas to flow along the center line of the flow path 7. This results in a vortex 62 moving at an angle of 90° with respect to the current.

The behavior of this liquid or slurry will be explained in more detail with reference to FIGS. The slurry is connected to the connecting cylinder 6.
8a and flows into the apparatus of the present invention. The liquid or slurry.

It flows into the cylindrical body 60 which has a much larger volume than the flow passage 7 of the same size, where the flow velocity decreases.
Internal pressure decreases. The liquid or slurry then flows towards the recirculation section 63, which is composed of a series of bent arms, and this liquid or slurry flows through the flow path 7 section and inside the cylindrical body 60. It is directed to pass through the wing 67, which occupies a relatively small area compared to the air flow, where it is accelerated and passes between each fi 67.67 at an angle of 90'' to the normal streamline. By changing the direction of the line, a vortex 62 is created in the flow path 7 in the downstream part of the device of the present invention.
is generated. The liquid or slurry passing through the plurality of blades 67 encounters a low-pressure area generated by well-known physical laws, which expands and combines the air and gas mixed in the liquid or slurry. It is directed into a thin flow and extends into the flow path 7 connected downstream, producing the vortex flow 62 described above. Due to the existence of a thin flow layer and a low pressure zone, the expanded and coalesced bubbles move into the vortex 62, and the exhaust pipe 66 extended into the vortex 62 stabilizes the vortex 62 and removes the air and gas present in the vortex IN, 62. The dynamic behavior of the system, including the fact that the vortex 62, which has a much lower internal pressure than the rest of the system that serves to discharge the gas, is at a higher pressure than atmospheric pressure will be discussed later. In this way, the air or gas in the vortex 62 is discharged from the vortex 62 into the atmosphere through the exhaust pipe 66.

The discharge of air or gas in the vortex 62 is further facilitated by the length of the vortex 62 produced by the above-mentioned action. This provides the necessary time for the gas to be removed from the flow and exhausted.

The air or gas separated in the vortex f&62 is discharged into the atmosphere through the exhaust pipe 66 in the opposite direction of the flow. In the case of extraction, the pressure within the vortex 62 must be lower than the pressure within the flow path 7 but higher than atmospheric pressure.

FIG. 5 shows one method by which the pressure gradient between the pressure within the vortex flow 62 described above and atmospheric pressure may be maintained at an appropriate level. The liquid or slurry is drawn from the tank 71 by a pump 72 and a flow control valve 731 M74.
The function of the device 74 of the present invention, which is flown through the valve 76, generates a vortex in the flow path 7 as described above, and the air and gas mixed therein are moved by the mechanism described above. This air or gas is discharged from the system from the exhaust pipe 9 via the flow path 7a and becomes 4P! It is circulated to an appropriate location such as 71.

As is understood in ordinary technical practice, if the air or gas in the vortex 62 is vented to the atmosphere without other means, the pressure in the vortex 62 generated in the flow path 7 will be Fluctuations in the flow rate of the liquid or slurry through the device 74 of the invention caused by the adjustment of the flow control valve 76, which must be greater than the pressure at the location of the outlet 80, affect the described function of the device 74 of the invention and the pressure in the vortex flow. The effects are also more recognized than prior art techniques. That is, as the flow rate decreases, the passing flow rate decreases, the pressure within the vortex changes, and the length of the vortex changes accordingly, all of which reduce the optimal effectiveness of the device. 0
As recognized by those of ordinary skill in the art, the pressure drop produced by the device 74 of the present invention varies as a function of the flow rate through the device. That is, as the meteor decreases, the pressure loss decreases, and as the meteor increases, the pressure loss also increases. This phenomenon is used to control the properties and effects of the entire system in the following manner. That is, the differential pressure generated in the device 74 of the present invention is continuously determined by Δ14 using a known and appropriate differential pressure detection device 81. As mentioned above, the differential pressure signal generated in proportion to the flow passing through the device 74 of the present invention is transmitted to the regulator 82, and when the signal increases, the opening degree of the flow control valve 76 is decreased, and when the signal decreases, the differential pressure signal is transmitted to the regulator 82. The opening of control valve 76 is increased.

The signal from this regulator 82 is simultaneously transmitted to a second regulator 83, and when the signal increases, the opening degree of the valve 84 is decreased, and when the signal decreases, the opening degree of the valve 84 is increased. That is, this control operation controls the relationship between the pressure in the flow path 77, the pressure in the vortex flow 62, and the pressure at the outlet portion of the exhaust pipe 79 so that the system operates with maximum effect over the entire range of flow rates. It is done like this. Note that this control method can also be achieved by adjusting these control coefficients by L movement.

Note that the present invention is not limited to the illustrated embodiments,
It goes without saying that various improvements and modifications can be made without departing from the spirit of the invention.

1 Effect of the Invention 1 Since the present invention is as described below, it is only necessary to interpose the cylindrical main body 60 in the middle of the flow path, and the piping space is saved.
(2) It is possible to provide an in-line deaerator for wave-fed liquid or flow-fed slurry that does not require installation space and consumes extremely little power.

[Brief explanation of drawings]

Fig. 1 is a front view of a typical raft pulp preparation, bleaching, and papermaking process using the apparatus of the present invention; Fig. 2 is a vertical cross-sectional view of an embodiment of the apparatus of the present invention; and Fig. 3 is a cross-sectional view taken along line A-A. 4 is a perspective view showing the fluid behavior induced by the device of the present invention as a flow of slurry, and FIG. 5 is a front view of the device of the present invention with a pressure control mechanism added thereto. 60 ~ Cylindrical body 7 ~ Magic path 62 ~ Whirlpool
63 ~ Circulation section 64 ~ End surface ring plate 65 ~
End ring plate 66 ~ exhaust pipe 67 ~ rhombus 68a
, 68b ~ Connecting cylinder 69 ~ Ring plate agent 71 times l 2 2 g 6b

Claims (1)

[Claims] A cylindrical body interposed in the middle of a liquid or slurry flow path has a diameter larger than that of the flow path, and within the cylindrical body there are blades that circulate the liquid or slurry passing through the cylindrical body. The cylindrical body further includes an exhaust pipe having one end opened toward the downstream side of the central axis of the cylindrical body and the other end extending outward from the cylindrical body. In-line deaerator for flowing liquid or slurry