JP2007160215A - Method and apparatus for drying sludge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for drying sludge capable of also drying the sludge having a high water content in a short time utilizing natural cold air in a cold area. <P>SOLUTION: The method comprises placing a drying container 3 including the sludge on each drying shelf 2 arranging in a plurality of steps in a drying treatment house 1, in the nighttime, opening the drying treatment house 1, taking the cold air therein and freezing the sludge in the drying container 3, and in the daytime, closing the drying treatment house 1, also melting the frozen sludge by transmitting a visible light ray from a roof plate 4 and a peripheral wall 5 to increase a room temperature, dewatering and drying. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sludge drying method and a drying apparatus for freeze-drying sludge using natural cold air in a cold region.

  As a sludge dewatering and drying device for drying sludge generated in water purification plants, sewage treatment plants, rivers, ponds, and the like to the sun, a plurality of drying shelves 21 to 24 as shown in FIG. 25L is lifted and moved up and down to the height of the drying shelves of the respective stages by lifting and lowering the drying containers (filtering containers) 20 containing sludge at both ends of the drying shelves 21 to 24. , 25R are arranged, and the sludge-containing drying container 20 can be sun-dried while being sequentially moved from the lower drying shelf to the upper drying shelf by the lifter devices 25L, 25R (for example, Patent Documents). 1).

Japanese Patent No. 3616738

  However, in the multi-stage sludge dewatering and drying apparatus as described above, the plurality of drying shelves 21 to 24 are arranged in several stages up and down, so that the site area can be effectively used even when a large amount of sludge is sun-dried. However, since the high water content sludge having a water content of 95 to 97% pumped up from the water is only sun dried, there is a problem that it takes a long time for sun drying.

  Accordingly, an object of the present invention is to provide a sludge drying method and a drying apparatus capable of drying high water content sludge in a short period of time by using natural cold air in a cold region.

  In the sludge drying method of the present invention, a drying container containing sludge is placed on each drying shelf arranged in a plurality of stages in a drying treatment building, and the drying treatment building is opened at night to take in cold air. The sludge inside is frozen, the drying treatment building is closed during the daytime, and the frozen sludge is deiced and dehydrated and dried by transmitting visible light from the roof and surrounding walls to increase the room temperature. Is.

  In the sludge drying apparatus of the present invention, a plurality of drying shelves on which a sludge-containing drying container is placed are disposed in a drying treatment building, and the peripheral wall plate covers substantially the upper half of the roof plate and the peripheral wall of the drying treatment building. Are made of a material that transmits visible light, and a substantially lower half of the peripheral wall is covered with a shield curtain so as to be opened and closed.

  According to the sludge drying method and drying apparatus of the present invention, a drying container containing sludge is placed on each drying shelf arranged in a plurality of stages in the drying treatment building, and the drying treatment building is opened at night to take in cold air. In the daytime, the sludge is frozen, and the drying treatment building is closed.In addition, the frozen sludge is deiced and dried by increasing the room temperature by transmitting visible light from the roof and surrounding walls. It can be efficiently dried in a small number of days, and since natural cold air is used, it can be dried at a low running cost.

  According to the sludge drying apparatus of the present invention, cold air can be easily taken into the drying processing building by opening the shield curtain at night, and visible light is visible from the upper half of the roof plate and the peripheral wall during the daytime. In addition, the shield curtain is closed and the lower half of the peripheral wall is sealed to enhance the greenhouse effect, so that the frozen sludge can be deiced and dehydrated and dried effectively.

  A preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a sludge drying apparatus capable of carrying out the method of the present invention.

  The sludge drying method according to the present invention freezes and dries sludge in a cold region using, for example, a sludge drying apparatus as shown in FIG. In FIG. 1, the sludge drying apparatus has a plurality of drying shelves 2 arranged vertically in a drying treatment building 1, and a drying container 3 containing high water content sludge is placed on each drying shelf 2. I have to.

  The drying treatment building 1 is sown with a roof plate 4 made of a transparent resin plate such as a polycarbonate corrugated plate or a glass plate that allows visible light to pass through the roof, and the substantially upper half 5a of the peripheral wall 5 similarly transmits visible light. A peripheral wall plate 6 made of a transparent resin plate such as a polycarbonate corrugated plate or a glass plate is covered, and a substantially lower half 5b of the peripheral wall 5 is covered with an accordion-type shield curtain 7 or the like so as to be opened and closed. When the shield curtain 7 is used, the shield curtain 7 is preferably made of a transparent material that transmits visible light.

  Thus, at the time of sludge drying, the sludge in the drying container 3 is taken in at night by taking the cold air into the drying treatment building 1 by opening the shield curtain 7 of the drying treatment building 1 and opening the substantially lower half 5b of the peripheral wall 5. By the greenhouse effect of transmitting visible light from the roof plate 4 and the upper half 5a of the peripheral wall 5 during the daytime, and closing the shield curtain 7 of the drying treatment building 1 and closing the lower half 5b of the peripheral wall 5 in a sealed state. The room temperature can be raised, and the frozen sludge in the drying container 3 can be defrosted and dehydrated and dried at this room temperature. As a result, the high water content sludge can be dried in a short period of time.

  If the greenhouse effect cannot be fully expected in the daytime on rainy or cloudy days, increase the room temperature using the residual heat from the compressor motor, etc. used in the adjacent water purification plant. Is advantageous as an energy saving measure.

It is sectional drawing of the drying apparatus of the sludge which can implement the method of this invention. It is a front view of the sludge dehydration drying apparatus of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drying processing building 2 Drying shelf 3 Drying container 4 Roof board 5 Perimeter wall 5a Substantially upper half 5b Peripheral lower half 6 Perimeter wall board 7 Shield curtain

Claims (2)

  Place drying containers with sludge on each drying shelf arranged in multiple stages in the drying treatment building, open the drying treatment building at night and take in cold air, freeze the sludge in the drying vessel, and in the daytime A method for drying sludge, wherein the drying treatment building is closed, and the frozen sludge is deiced and dehydrated by transmitting visible light from a roof plate and a peripheral wall to increase indoor temperature. A plurality of drying shelves for placing sludge-containing drying containers are placed in the drying treatment building, and the peripheral wall plate covering the roof plate of the drying treatment building and the substantially upper half of the peripheral wall is made of a material that transmits visible light. The substantially lower half of the peripheral wall is covered with a shield curtain so that it can be opened and closed.

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