JPH02265624A - Dehydrating process and device - Google Patents

Abstract

PURPOSE:To dehydrate efficiently by bringing a material to be dehydrated into contact with concentrated solution of salt water, sugared water or the like through a film and dehydrating by means of osmotic pressure. CONSTITUTION:When a material 1 to be dehydrated is brought into contact with concentrated solution 3 of salt water, sugared water or the like through a film 2, the water content of the material 1 to be dehydrated is transferred into solution 3 by means of osmotic pressure. The pressure of solution 3 is risen by a pressurizing pump 4 and water content 6 is so prepared and concentrated by a reverse osmosis film 5 as to control the solution 3 so as to retain almost constant high concentration. Dehydration of high efficiency can be carried out effectively by said process, not by mechanical compression.

Description

[Detailed Description of the Invention] This invention provides 1. water-containing solids such as fresh fish and raw vegetables;
Water-containing sludge such as sludge is effectively dehydrated with high efficiency. The present invention relates to a method and an apparatus.

When dehydrating water-containing solids such as fresh fish or water-containing sludge such as sludge at room temperature without using methods such as solar drying, heating, or freezing, mechanical compression is often inconvenient. In other words, in the case of the former (fresh fish, etc.), it goes without saying that compression processing is inappropriate in terms of commercial value, but in both cases, compression densifies the particles and narrows the water flow path, so it is generally Specifically, even if the pressure is increased, the dehydration effect does not increase accordingly.

In view of the above, the present invention does not rely on mechanical compression when dehydrating the above objects at room temperature.

The present invention provides a method and apparatus for effectively dehydrating a material to be dehydrated by bringing it into contact with a solution maintained at a high concentration through a membrane and utilizing the osmotic pressure generated at this time, which will be explained in more detail with reference to the drawings below. do.

Figure 1 is a diagram explaining the principle of the present invention in detail, Figures 2 and 3 are explanatory diagrams of an embodiment for dehydrating water-containing solids such as fresh fish, Figure 4, Figure 5, and Figure 6 are sludge. An explanatory view of an example in which water-containing sludge such as the following is dehydrated is shown, respectively.

In FIG. 1, when the dehydrated material 1 is brought into contact with the raw solution 3 (such as salt water or sugar water) through the membrane 2, the water in the dehydrated material 1 moves to the solution wI3 due to osmotic pressure. At this time, since almost no mechanical compaction occurs in the material to be dehydrated 1,
Excellent dehydration effect can be obtained. This dehydration dilutes the solution [3], which is then pressurized by a pressure pump 4 and transferred to a reverse osmosis membrane 5.
The water 6 is separated and concentrated, and the solution 3 is controlled to always maintain a substantially constant high concentration. Dehydrating the object to be dehydrated 1 4
(The progress of B is caused by osmotic pressure, and since osmotic pressure is proportional to the difference in concentration of the solution, effective dehydration can be achieved by always maintaining a concentrated solution concentration of 1 or more.

Next, an example of dehydration of fresh fish will be explained with reference to FIGS. 2 and 3. The cleaned fish 1° is sealed and packaged with a membrane 2° by a packaging machine 7 and then supplied to a liquid tank 8. The liquid tank 8 is equipped with a conveyor 9 and filled with 3° of a solution such as salt water or sugar water, and the conveyor speed is set in accordance with the residence time to obtain the desired dehydration rate. In order to effectively effect the osmotic action on the entire surface of the fresh fish 1°, the packaging machine 7 is preferably vacuum packed so that air does not enter between the fresh fish 1° and the membrane 2°. As described above, 1゜ fresh fish is dehydrated by the action of osmotic pressure, but the solution 3゜ diluted with leachate is constantly pressurized with a pressure pump 4゜ and water is 6゜ through a reverse osmosis membrane 5゜.
The liquid is separated and concentrated and returned to the liquid tank 8. In the figure, 10 indicates a flow rate regulating valve. With the above configuration, by always keeping the solution 3' at a constant concentration, a high and stable osmotic pressure is maintained, so that effective dehydration of fresh fish etc. is continuously performed.

Next, an example of dehydration of water-containing sludge such as sludge will be explained with reference to Fig. 4, Pole No. 5 (X-x sectional view in Fig. 4) and Fig. 6 (detailed view of section Y in Fig. 5). . This dehydrator consists of a rotating cylinder 8'' whose interior is filled with a solution 3'' such as salt water or sugar water and whose outer periphery is made of a porous material 11, and a belt-shaped membrane 2 that moves in pressure contact with the outer periphery of the cylinder 8''. ” and porous belt 12. It also includes a reverse osmosis membrane device 9, which includes a pressure pump 4, a reverse osmosis membrane 5, a flow rate adjustment valve 10, etc. In the figure.

13.34 are rollers that support the belt-shaped membrane 2'' and the porous belt 12, 15 is a rotating joint, arrow R is the rotation method of the rotating cylinder 8'', and arrow S is the moving direction of the membrane 2'' and the belt 12. , respectively. Note that the drive device for the two-rotation cylinder and the belt, the cleaning device, etc. are not shown.

With the above configuration, when the water-containing sludge 1'' is supplied between the belt-shaped membrane 2'' and the porous belt 12 from the direction of arrow A, the water-containing sludge 1'' passes through the membrane 2'' to the porous body 11. Since it comes into contact with the melt 8!3'' that has flowed out to the outer periphery, it is dehydrated by the action of osmotic pressure, moves between the membrane 2'' and the belt 12, and is discharged. At this time, only the pressure based on the tension of the belt 12 is applied to the sludge l'', so the particles are not compacted to the extent that it interferes with dewatering, and by setting the tension of the belt 12 appropriately, dewatering can be effectively achieved. Yes, same as above example**
The solution 3'' diluted with the dehydrated water is separated and concentrated by a reverse osmosis membrane device consisting of a pressure pump 4, a reverse osmosis membrane 5, a flow rate adjustment valve 10, etc., and can be maintained at a high concentration at all times. Therefore, effective dehydration is carried out continuously.

According to the present invention, as is clear from the above description.

9 When dehydrating water-containing solids such as fresh fish and raw vegetables, water-containing sludge such as sludge, etc. at room temperature, without using mechanical compression,
It can be dehydrated effectively with high efficiency and is very useful industrially.

[Brief explanation of drawings]

Figure 1 is a diagram explaining the principle of the present invention in detail, Figures 2 and 3 are explanatory diagrams of an embodiment for dehydrating water-containing solids such as fresh fish, Figure 4, Figure 5, and Figure 6 are sludge. An explanatory view of an example in which water-containing sludge such as the following is dehydrated is shown, respectively. The symbols in the figure represent the following: l -1 Material to be dehydrated 1゛ -1 Fresh fish 1"-1 Water-containing sludge 2 2'2"-1 membrane 3 3° 3"-1 Solution 4 4'4" -1 Pressure pump 5 5°
5"-1 Reverse osmosis membrane 6 6"6"-1 Water 7-1 Packaging machine 8-1 Liquid tank 8"-1 Rotating cylinder] 1-1 Porous body 12-1 Porous body belt

Claims (3)

[Claims] (1) The material to be dehydrated is brought into contact with a concentrated solution such as salt water or sugar water through a membrane to dehydrate it by osmotic pressure, and the solution is concentrated by reverse osmosis to maintain a nearly constant high concentration at all times. A dehydration method characterized by: (2) Equipment for supplying the material to be dehydrated in sealed packaging with a membrane, a liquid tank filled with a solution such as salt water or sugar water and equipped with a conveyor device inside, and a reverse osmosis membrane device for concentrating the solution. It is characterized by continuously dehydrating the dehydrated material using osmotic pressure while maintaining the solution concentration at a nearly constant high concentration.
For example, a dehydrator for fresh fish. (3) A rotating cylinder whose interior is filled with a solution such as salt water or sugar water and whose outer periphery is made of a porous material, a membrane belt and a porous material belt that move in pressure contact with the outer periphery of the rotating cylinder, and which concentrate the solution. Dewatering of water-containing sludge such as sludge, for example, consists of a reverse osmosis membrane device, and is characterized by continuously dewatering the material to be dehydrated supplied between the belts using osmotic pressure while keeping the solution concentration at a nearly constant high concentration. Device.