Patent Description:
In the course of producing various products such as pharmaceutical medicines, cosmetics, foods, and fine chemicals, air bubbles are formed in a liquid form of processing substance, and these air bubbles cause various troubles in production of these products. Because of this, defoaming is performed to a processing substance by using a vacuum deaerator, in this defoaming, it is required to continuously remove the air bubbles in the liquid having from a low viscosity to a high viscosity in a vacuum state. To cope with such a problem, the following prior art references are known as a vacuum deaerator equipped with a refining device. The applicant of the present invention has also brought the deaerator manufactured by M. Techniques Co. , Ltd to the market.

However, while not only the apparatus can remove fine air bubbles, but also be able to connect in-line to realize the various functions such as a continuous defoaming operation under an enclosed environment, a continuous removal of a solvent or a VOC, a centrifugal separation effect, a thin film effect, a refining effect, a crushing effect, and a degassing effect in a single unit, further improvement of washability, high quality control, and high production efficiency are required, in this field of technology, there has been still a problem in smoothly discharging a processing substance in a vessel.

Especially in the case of the processing substance having a high viscosity, the degree of vacuum becomes very high in order to enhance the degassing effect. However, as the degree of vacuum increases, it becomes difficult to discharge the processing substance that has been completed the processing from under the vacuum, thus, in many cases, the substance cannot be discharged.

When such a situation that the substance cannot be discharged occurs, it has been necessary to carry out following interrupted discharge. The interrupted discharge means a discharge operation in which the continuous degassing is temporarily stopped, then, after the degree of vacuum is loosened, or the pressure therein is returned to an atmospheric pressure, the processing substance is discharged from the vessel. When the processing substance is discharged by this interrupted discharge, the inside of the vessel is again evacuated, and then, after the degree of vacuum reaches a target pressure, the processing substance is again supplied to restart the continuous operation, however, when the processing substance accumulates inside of the vessel again, it is necessary to repeatedly carry out the continuous operation and interrupted discharge so that the degree of vacuum is loosened, or the processing substance returned to an atmospheric pressure is discharged from the vessel, thus, the efficiency thereof is very poor.

In Patent Document <NUM>, a vacuum deaerator equipped with a scraper installed inside of the vessel is disclosed; but this scraper merely scrapes off the processing substance that is adhered to an inner wall surface of the vessel. Therefore, as far as the discharge performance is concerned, this has not been to realize the discharge action to a discharge port, in other words, not to realize the push-in action to a discharge pump.

The present invention has an object to provide a vacuum deaerator equipped with a refining device which suppresses the occurrence of a situation in which interrupted discharge is performed in performing degassing treatment on the processing substance having such as high viscosity and continuously discharges the processing substance from high vacuum condition.

In the present invention, processing substance having high viscosity means a highly viscous liquid such as a polymer solution and a paste, and in the terms of viscosity, it can be described in <NUM>,<NUM> mPa·s or more. The highly vacuum condition means that the degree of vacuum thereof is <NUM> Pa or less.

The present invention solves the problems by providing a vacuum deaerator equipped with a refining screen as defined in claim <NUM> as appended hereto, in which in the vacuum deaerator which introduces a liquid form of processing substance into a vessel having a vacuum to perform deaeration and then discharges the processing substance to outside of the vessel, a rotating rotor equipped with the refining screen arranged in the vessel and a rotating discharge blade for the purpose of discharging the processing substance from inside to outside of the vessel that is separately to the rotating rotor are installed. The refining screen is arranged at an outer circumferential part of the rotating rotor. The rotating discharge blade is a screw type rotating discharge blade extending spirally. The rotating discharge blade has a large diameter at its upper part and a small diameter at its lower part. A lower end of the rotating discharge blade reaches the discharge port. The vessel has funnel part at a lower part of the vessel. The rotating discharge blade is configured to push the processing substance along an inner wall surface of the funnel part.

The refining screen performs the function to enhance a degassing effect by refining the processing substance. The refining screen is shown arranged in the rotating rotor.

The rotating discharge blade performs the function to forcibly carry the processing substance toward a discharge port of the vessel by rotating.

The present invention can be implemented by installing a temperature adjusting mechanism on the vacuum vessel.

The present invention can be implemented by installing a discharge pump such as a rotary positive displacement type uniaxial eccentric screw pump or a high vacuum pull-out type diaphragm pump on the discharge port of the vessel for the purpose of continuously pulling out the processing substance from the vessel. By this, because of the synergistic effect of both the push-in action of the processing substance into the discharge pump due to the rotating discharge blade and the suction action of the discharge pump, the continuous discharge can be realized even with a highly viscous processing substance.

The present invention can be provided a vacuum deaerator equipped with a refining screen having an enhanced function of continuously discharging a processing substance.

With this, the processing substance can be continuously discharged from inside of a vessel even in the case of degassing treatment under a high vacuum condition.

In addition, even in performing degassing treatment to a highly viscous processing substance, the occurrence of the situation in which interrupted discharge is performed can be suppressed so that the processing substance can be continuously discharged under a high vacuum condition.

[<FIG>] This is an explanatory drawing of an inner structure of the vacuum deaerator equipped with the refining screen according to the embodiment of the present invention.

Hereinafter, the embodiment of the present invention will be explained on the basis of the drawing.

In the vacuum deaerator equipped with the refining screen, a processing substance in the form of liquid is introduced into a vessel <NUM> having vacuum inside thereof and degassed, then, the processing substance is discharged to outside of the vessel <NUM>.

Inside of the vessel <NUM>, a refining device <NUM> provided on a rotating rotor <NUM> and a discharge device <NUM> to discharge the processing substance to outside of the vessel <NUM> are arranged. The processing substance is discharged to outside of the vessel through a discharge port <NUM> by a rotating discharge blade <NUM> of the discharge device <NUM> after being performed refining and degassing by the refining device <NUM>.

The vessel <NUM> is a container having hermeticity kept in a high vacuum of about <NUM> Pa to <NUM> Pa. In this embodiment, a container main body <NUM> and a cover body <NUM> arranged above the main body are connected so as to be openable and closable. Specifically, the container main body <NUM> comprises a cylindrical part <NUM> on the upper part of the main body and a funnel part <NUM> whose inner diameter is gradually reduced from the cylindrical part <NUM> on the lower part of the main body, and the discharge port <NUM> to discharge the processing substance after the degassing treatment to the outside is arranged on the lower end of the funnel part <NUM>.

The container main body <NUM> is provided with a temperature adjusting mechanism <NUM> such as a jacket which flows a temperature adjusting fluid such as hot water or cold water along the outer wall surface of the main body. Note that the temperature adjusting mechanism <NUM> may also be arranged on the cover body <NUM>. The temperature adjusting mechanism <NUM> may be used to keep the processing substance inside the vessel <NUM> in a prescribed temperature range or to heat or cool the processing substance as necessary.

The cover body <NUM> is provided with a vacuum port <NUM> to keep the inside of the vessel <NUM> in the vacuum state. A gas inside of the vessel <NUM> is discharged to outside by a vacuum pump <NUM> that is connected to the vacuum port <NUM>, so that the pressure inside of the vessel <NUM> becomes in a vacuum state with a prescribed pressure.

Further, the cover body <NUM> is provided with an introduction port <NUM> to charge the processing substance into the vessel <NUM>, so that the processing substance is introduced into a vessel <NUM> from a supply source <NUM> such as a tank that is connected to the introduction port.

The flanges of both the container main body <NUM> and the cover body <NUM> are disposed so as to be faced with each other and are fixed ensuring airtightness under the reduced pressure thereby being configured integral vessel <NUM>. Here, the vessel <NUM> may be divided into two portions at any position, and the connecting means therebetween may be arbitrary changed.

The refining device <NUM> is arranged at the position corresponding to the cylindrical part <NUM> of the container main body <NUM>; this includes a flat disc-shaped rotating rotor <NUM>, a first refining screen <NUM> and a second refining screen <NUM> that are arranged at outer circumferential part of the rotating rotor. The rotating rotor <NUM> is rotated by a cylindrical driving axis <NUM>. Specifically, the driving axis <NUM> is rotated by an electric motor <NUM> for the rotor arranged on the upper outside of the cover body <NUM> via a power transmission unit <NUM> for the rotor.

In an inner circumferential side of the rotating rotor <NUM>, an annular path <NUM> that is connected to the introduction port <NUM> is arranged. The processing substance is radially introduced to the rotating rotor <NUM> from a charging port <NUM> at the front end of the annular path <NUM>.

The upper surface of the rotating rotor <NUM> is made to a smooth flat surface; the charged processing substance is thin-filmed on the upper surface due to a centrifugal force of the rotation of the rotating rotor <NUM>.

The processing substance that advances toward the outer circumferential direction of the rotating rotor <NUM> due to the centrifugal force passes through the first refining screen <NUM> and the second refining screen <NUM> that are annularly arranged, whereby the defoaming effect can be enhanced. The one refining screen may be only used; by using the first refining screen <NUM> having comparatively large mesh such as a punching plate and the second refining screen <NUM> having comparatively small mesh such as a metal mesh, the refinement can be sequentially achieved. Therefore, it is advantageous in that the smooth and appropriate refinement can be achieved. More refining screens such as a third refining screen and a fourth refining screen may also be used.

The processing substance having passed through the rotating rotor <NUM> and the second refining screen <NUM> becomes mist and collides with an inner wall surface of the cylindrical part <NUM>. By this collision, the degassing is further promoted, and the processing substance after the collision forms thin film fluid along the inner wall surface of the cylindrical part <NUM>, so that fine bubbles can also be defoamed.

The discharge device <NUM> is provided with the rotating discharge blade <NUM> that is rotated by a rotary shaft <NUM> and is arranged on the position corresponding to a funnel part <NUM> in the container main body <NUM>.

The upper end of the rotary shaft <NUM> penetrates through the inside of the cylindrical driving axis <NUM> and rotates separately from the rotating rotor <NUM> by an electric motor <NUM> for the blade via a power transmission unit <NUM> for the blade. Note that, the term "separately" means that the rotating discharge blade <NUM> and the rotating rotor <NUM> rotate separately, the rotation directions thereof may be the same or different. Since the rotation of the rotating rotor <NUM> is performed for refining the processing substance, the rotating rotor <NUM> is operated with the optimum rotation number for the purpose. On the other hand, since the rotation of the rotating discharge blade <NUM> is performed to smoothly discharge the processing substance after completion of the degassing treatment to outside of the vessel <NUM>, the rotation of the rotating discharge blade <NUM> is operated with an optimum rotation number for the purpose. Accordingly, regardless of whether the rotation driving sources is the same or not, they rotate separately.

Specifically, the rotation speed of the rotating rotor <NUM> is appropriate in the range of about <NUM> rpm to <NUM> rpm, and the rotation speed of the rotating discharge blade <NUM> is appropriate in the range of about <NUM> rpm to <NUM> rpm, although these rotation speeds are variable depending on the size of the vacuum deaerator.

In this embodiment, the rotating discharge blade <NUM> is a screw type rotating discharge blade extending spirally. The upper part of the rotating discharge blade <NUM> having a large diameter is supported by the rotary shaft <NUM> via a supporting body <NUM>, while the lower part of the rotating discharge blade <NUM> having a small diameter is directly supported by the rotary shaft <NUM>; the lower end of the rotating discharge blade <NUM> reaches the position facing to the discharge port <NUM>. In the case of a highly viscous processing substance, since the processing substance adheres to the inner wall surface of the vessel <NUM> for which causes the processing substance does not easily reach to the center part of the vessel, the upper part of the rotating discharge blade <NUM> having a large diameter has a hollow state without a blade in the center, however, it may be carried out in a such way that the rotating discharge blade <NUM> is provided so as to reach the rotary shaft <NUM> over the entire area in the up and down direction, and no hollow state is existed in the center.

By rotating the rotating discharge blade <NUM>, even with a highly viscous processing substance, occurrence of retaining more than necessary of the processing substance inside the vessel can be suppressed by forcibly being sent to the discharge port <NUM>.

As mentioned above, the processing substance after completion of collision forms a thin film fluid along the inner wall surface of the cylindrical part <NUM> to defoam the finer air bubbles, but it is appropriate to limit the retention amount of the processing substance to such a degree that the function thereof does not impaired. Specifically, it is appropriate to limit the degree at which the processing substance is accommodated in the lower funnel part <NUM> at the most, however when the length of cylindrical part <NUM> in the axial direction is made longer, the retention amount may be retained by halfway.

The lower part of the vessel <NUM>, in this example, the lower part of the cylindrical part <NUM>, is made as the funnel shape according to the present invention which is more advantageous in the point that the funnel shape is gradually pressurized and the push-in effect on the discharge pump <NUM> that is connected to the charging port <NUM> is enhanced.

Depending on the kinds of fluid, the discharge pump <NUM> may not be connected to the charging port <NUM>, but in the case of a highly viscous processing substance, it is preferable to install a rotary positive displacement type uniaxial eccentric screw pump or a high vacuum pull-out type diaphragm pump as the discharge pump <NUM>.

As a result, by rotation of the rotating discharge blade <NUM> arranged along the inner wall surface of the funnel part <NUM>, the processing substance can be pushed into the discharge pump <NUM> while being pressurized, and even with a highly viscous processing substance, the continuous discharge can be realized by the synergistic effect of both the push-in action and the suction action of the discharge pump.

As a result, even in the case of a highly viscous processing substance, the continuous degassing treatment can be carried out with suppressing the necessity of the interrupted discharge.

As an example, one sheet of the rotating discharge blade <NUM> is shown, but it may be multiple sheets of two or more, may be continuously extended or may be intermittently extended.

Claim 1:
A vacuum deaerator equipped with a refining screen (<NUM>, <NUM>), wherein
in the vacuum deaerator which introduces a liquid form of processing substance into a vessel (<NUM>) via an introduction port (<NUM>), the vessel having a vacuum inside thereof to perform deaeration and then discharges the processing substance to outside of the vessel (<NUM>) via a discharge port (<NUM>),
a flat disc-shaped rotating rotor (<NUM>) equipped with the refining screen (<NUM>, <NUM>) arranged in the vessel (<NUM>) and a rotating discharge blade (<NUM>) having function to discharge the processing substance inside of the vessel (<NUM>) to outside of the vessel (<NUM>) that separately rotates from the rotating rotor (<NUM>) are installed,
wherein the refining screen (<NUM>, <NUM>) is arranged at an outer circumferential part of the rotating rotor (<NUM>);
the rotating discharge blade (<NUM>) is a screw type rotating discharge blade extending spirally;
the rotating discharge blade (<NUM>) has a large diameter at its upper part and a small diameter at its lower part;
a lower end of the rotating discharge blade (<NUM>) reaches the discharge port (<NUM>);
the vessel (<NUM>) has funnel part (<NUM>) at a lower part of the vessel (<NUM>); and
the rotating discharge blade (<NUM>) is configured to push the processing substance along an inner wall surface of the funnel part (<NUM>).