JPH0613159B2 - Sludge treatment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention defines a dehydration treatment area inside a filtration section having a dehydration hole formed over the entire length of a horizontally long right circular cylinder, and first, sludge and the like are filtered. To the front dewatering section through a sludge etc. feeding section, make a flocculated floc shape and feed it toward the axial center direction to fill it, and after half filling with the filling pressure, rotate the screw shaft and discharge side The present invention relates to a method for treating sludge or the like, which enables the dehydration treatment over the entire length of the filtration section by pumping to increase the initial filling degree and efficiently supplies coagulated flocs to contribute to the improvement of the dehydration efficiency and the treatment amount.

[Prior Art] Conventionally, a continuous squeezing machine that has been used to dehydrate sludge or the like throws the sludge or the like on the front side of a horizontally installed cylindrical filtration unit at an upper side orthogonal to the axis. Since it was general that the hopper to be sewn was opened with a length of about 20% or more of the total length, a dehydration hole for filtration cannot be formed in the opening portion occupied by the hopper, therefore, Although a dehydration hole is formed in the other peripheral wall portion of the filtration section under the hopper, sludge and the like are only in contact with the dehydration hole by their own weight, so that only gravity filtration is possible and the moisture content is reduced. There is no effective squeezing force, and therefore, even if the filter section is considerably long, the portion occupied by the hopper has a low dehydration efficiency, and the continuous squeezing machine as a whole must be oversized accordingly. There was a problem such as not becoming.

Further, in the hopper type, since the floc flocs processed by the flocculation and mixing tank using the hopper as the chute is dropped and supplied, the flocs collide with the body of the screw shaft and are broken. Therefore, in order not to break it,
A large amount of flocculant is required, but flocculation flocs containing a large amount of flocculant become viscous and clog the punching part such as gold steel in the filtering part, resulting in a decrease in treatment amount and poor water content. In addition, in order to control the liquid level, electrodes are attached to the hopper to measure the liquid level.However, since it is provided in the sludge passage part, malfunctions are inevitable and the electrode rod is damaged. It has the drawback of being transferred into the screw and destroying punching and the like.

[Problems to be Solved by the Invention] Therefore, according to the present invention, the continuous squeezing machine according to the above-mentioned conventional art is provided with a hopper having a length of about 20% or more of the total length on the upper side orthogonal to the axial center to the front part of the filtering part. Therefore, the dehydration hole cannot be formed in the opening portion, and the dehydration hole is formed in the lower side of the hopper, but sludge and the like supplied only by gravity has a low filling pressure and is preferable. Since it is not possible to contact the dehydration hole with a pressure that produces a dehydration effect, the initial filling point, which is an effective filling pressure, is closer to the discharge side, and in order to produce a cake with a desired water content, it is necessary to lengthen the filtration part accordingly. If there is an existing filling point at the forefront, it is possible to downsize the continuous squeezing machine, and further, if it is pressed in from the direction perpendicular to the screw shaft, the flocculation flocs collide with the screw shaft. Because the floc flocs break , Sludge to prevent the flocculation flocs aggregated in the closed flocculation mixing tank from being pushed into the screw from the axial direction so that the sludge pump pressure is applied to the screw surface at a low pressure so that the flocculation flocs are not broken. The object of the present invention is to provide a processing method of.

[Means for Solving the Problems] That is, according to the present invention, a dehydration hole having a horizontally long right cylindrical shape is formed over the entire length, a side wall is provided at a front end portion and a cake discharge port is provided at a rear end portion, and gold steel is provided inside. A screw shaft having spiral screw blades is rotatably pivoted on a tapered barrel having a large diameter from the front end toward the rear end, and the filter is provided to the filter. Forming a dewatering area over the entire length of the front end, and opening a supply port toward the axial direction on the side wall of the front end to connect a sludge equalizing pumping section composed of a coagulation mixing tank, a stirrer, etc. The flocculated sludge sludge from the pumping unit is first pumped to the front part of the dehydration treatment zone at the front end of the screw blade and then to the axial direction of the screw blade so as to follow the lead direction of the screw blade. While holding in the form of floc After being supplied in a stationary state and sequentially filled up to a semi-dewatering state at the filling pressure, the screw shaft is rotated to dehydrate in the dehydration treatment area, and then the rotation is sequentially performed through the front portion of the dehydration treatment area. The method for treating sludge or the like is characterized in that the cake is extruded from the discharge port by being pumped to the discharge port side while being dehydrated in the dehydration treatment area consisting of the screw shaft.

The dehydration treatment area (hereinafter, simply referred to as a treatment area) in the present invention means a space formed between the inner side of the filtration section and the screw shaft.

[Operation] According to the present invention constituted by the above means, the thrust bearing of the screw shaft is provided in the central portion of the side wall of the front portion of the filtering portion, and the supply port is opened in the upper portion thereof in the axial direction. , The supply port is via a pump that should pump sludge,
Since it is connected to a sludge equalizing pumping section comprising an aggregating and mixing tank for the sludge and an aggregating admixture tank, the aggregating and admixing tank is filled with sludge and the like, and an appropriate amount of the aggregating admixture is mixed and adjusted. If the pump is operated, sludge containing an appropriate amount of coagulant admixture is injected into the coagulation and mixing tank, and the coagulation and mixing tank agitator pressurizes the coagulated and mixed floc to direct it from the supply port toward the axial direction. Approximately 0.1 to 0.2 kg to the front part of the dehydration section at the front end of the screw blade so that it rides on the screw surface.
Since it is pumped at a sludge pump pressure of / cm ² , this supply does not break the floc.

At this time, since the screw shaft has not been rotated yet, the flocculated flocs due to the sludge or the like that has been pressure-fed gradually fills the front part of the dehydration section, and the filling pressure increases, so that the water content in the filtration section of this section increases. The amount of water that is squeezed out and removed through the dehydration hole increases. When the screw shaft is turned to avoid this timing, the semi-dehydrated sludge and the like is further squeezed and dehydrated in the treatment area while being pressure-fed to the discharge port side to be a complete cake and extruded from the discharge port.

Further, since new sludge and the like are continuously pumped into the treatment area through the front portion of the dehydration section, the dehydration treatment is continuously carried out, so that the front portion of the treatment area is already filled with pressure. Since it is in a semi-dewatered state, the entire length of the filtration section is effectively used for dehydration and an appropriate water content is obtained, so the filtration section is lengthened to increase the filtration area or the retention time of sludge etc. is extended. Since the same effect as described above is obtained, it is possible to reduce the size of the continuous pressing machine.

[Embodiment] An embodiment will be described below with reference to the drawings in order to further clarify the gist of the present invention.

In FIG. 1, a continuous pressing machine A comprises a dewatering section 1 and a sludge equal pressure feeding section 2 (hereinafter simply referred to as a pressure feeding section). The dewatering section 1 is a punching plate and has a small diameter dewatering hole 111a on the entire circumferential surface. A cylindrical portion 111 in the shape of a right circular cylinder formed by innumerable holes, and gold steel attached inside the cylindrical portion 111.
112 is a filtration unit 11 and a supply port 1 for sludge or the like at the front end of the filtration unit 11.
Open 21 toward the axis and screw shaft 13
Side wall 12 which is provided with a thrust bearing 122 and closes the filtering portion 11.
The shaft front portion 13a is pivotally supported on the thrust bearing 122, and the spiral body portion 131 having a tapered shape having a large diameter from the front portion toward the rear portion is rotated along the inside of the gold steel 112. It comprises a screw shaft 13 and a stand 14 on the outlet side (hereinafter, simply referred to as a stand).

In addition, the stand 14 is an upright hollow pillar, and has a side wall of a circle having substantially the same diameter as that of the filtering part in order to drop the cake discharged from the discharge port 113 at the rear of the filtering part 11 into the stand 14. Hole
141 is provided, supports the rear part of the filtering section 11 near the edge of the circular hole 141, and is a side wall portion at the time when the circular hole 141 is opened and concentric with the circular hole 141. A bearing 142 is provided to pivotally support the shaft rear portion 13b of the screw shaft 13, and further, a scraper 143 for adjusting a dehydration degree of discharged sludge to be dehydrated to generate a desired cake, and a scraper 143 for operating the scraper. Is provided with an operating portion 144 for operating the scraper 143 in the axial direction, and the shaft rear portion 13b is further extended by inserting the bearing 142, and is driven from a drive source (not shown) near the rear end. As described above, a sprocket or the like 133 is fixed, the rear end portion is pivotally supported by a bearing 145, and the filtration portion 11 is installed so as to be horizontal.

Further, the pressure feeding unit 2 connects the coagulation / mixing tank 21 and the pressure sensor 22 to a feed port 121 opened orthogonally to the upper portion of the side wall 12 of the dewatering unit 1 and a mud feed pump such as sludge (not shown). And a coagulant-mixing tank agitator 24 for storing the coagulant-mixing agent and appropriately supplying it.

The pressure sensor 22 detects the pressure of sludge or the like in the treatment area S and transmits it to a sludge supply pump (not shown), and adjusts the output of the sludge supply pump to constantly send the sludge or the like at an optimum pressure. Is.

Continuing, the operation of the present embodiment will be described. Sludge and the like filled in a tank for sludge not shown is operated by a mud feed pump to add an appropriate amount of coagulant admixture from an admixture tank not shown. Through the aggregating and mixing tank 21 while being mixed with, by the aggregating and mixing tank agitator 24, the mixture is agglomerated and mixed through the pressure feed pipe 23 disposed along the axis of the screw shaft 13 to the screw surface at a low pressure from the supply port 121. It is pumped into the front of the processing area S so that it rides.

Initially, if there is no sludge or the like in the front part of the processing area S, or if there is a small amount of sludge or the like, the screw blades 132 have not yet rotated so that the sludge or the like is pressed into the front part of the processing area S. Since it gradually fills up while almost staying in the tank, the pressure applied by the mud pump returns to the original atmospheric pressure until it fills up, and during this time, sludge and the like contact the filter section 11 by its own weight and dehydrate little by little by gravity. However, since the effective pressure dehydration action has not yet started, the pressure sensor 22 does not transmit any signal to the mud pump, and the mud pump operates at full power to rapidly remove sludge and the like. It is fed into the front part of the processing area S from the supply port 121.

Next, of the sludge and the like sent into the front part of the processing area S, some of it advances to the discharge port 113 side along the gaps of the screw blades 132 and the spiral, but most of it stays at the front part and eventually the front part. When it fills up with water, the internal pressure of the front part suddenly rises, a large amount of contained water begins to be squeezed out, and a large amount of water starts to flow down from the dehydration hole 111a. Transmits rotational force.

Even if the start of the screw shaft 13 is delayed, the pressure sensor 22 detects the excessive pressurization and stops or lowers the operation of the mud supply pump, so that there is no fear of damaging the screw blades 132 and the like. The sludge, etc., which has become semi-dehydrated by pressurizing the contained water and squeezing the contained water in the front part of the treatment area S, is guided to the screw blades 132 of the screw shaft 13 which started to rotate, and to the large diameter side of the part 131. The water contained is squeezed and squeezed more and more in the narrowed treatment area S, and the water contained therein is squeezed and leaches out immediately from the dehydration holes 111a formed in the entire circumference of the filtration section 11, so that the sludge to be dehydrated, etc. By the time it reaches the outlet 113, it has a perfect cake shape. The cake to be dehydrated is scraped off by a scraper 143 near the large diameter end of the body 131, and the
4 As it accumulates on the bottom, it is collected and processed as required. Further, as long as sludge or the like remains in the input tank, the sludge supply pump continuously feeds the sludge into the treatment area S, so that the dehydration treatment can be continuously performed.

As described above, in the present invention, in the conventional continuous pressing machine, there is a charging hopper, and the filtering part of the part hardly contributes to dewatering, but the dewatering action can be effectively performed over the entire length, and, Since the initial filling pressure is raised to dehydrate the semi-dehydrated state in the front part, the same effect can be obtained by making the filtration part longer than the length occupied by the hopper.

It should be noted that in the present embodiment, a description will be given of the scraper in the outlet side stand, which changes the discharge port area by sliding on the large-diameter end peripheral surface of the body part by the operation part capable of horizontally expanding and contracting the rod by appropriate means. However, the present invention is not limited to the examples, and these do not change the gist of the present invention within a range in which the above-mentioned objects, functions, and effects of the invention described below are achieved. Needless to say.

[Effects of the Invention] As described above in detail, according to the present invention, the filtration unit is provided so as to surround and surround the entire length of the screw shaft, and the dehydration treatment region is formed in the entire length, and is provided in the front portion thereof. A supply port is opened on the side wall in the axial direction, and sludge etc. is pressure-fed in the axial direction as coagulation flocs through a coagulation and mixing tank which is sealed from here. It is pressure-fed in the axial direction of this so as to follow the lead direction of
Since the flocculate flocs are supplied while being held on the screw blades while being held in the flocculation flocs, the flocculation flocs are not broken, and therefore a small amount of the flocculating agent is enough to prevent clogging during punching of the filtration unit. The initial filling point can be formed at the forefront of the filtration section, and the filling degree of sludge etc. supplied into the dehydration treatment area can be increased, thus increasing the filtration area and improving the dehydration efficiency and treatment amount. It is possible to further reduce the size, which reduces manufacturing costs and installation costs, and also allows a wide range of installation locations to be selected, such as transportation costs for sludge and cake. It is an excellent invention that has a great ripple effect, such as saving energy.

[Brief description of drawings]

The drawings show one embodiment of the method for treating sludge or the like of the present invention, and FIG. 1 is a side view showing a partial cross section of a main part of a continuous pressing machine. 11 …… Filtration part, 113 …… Discharge port 12 …… Side wall, 121 …… Supply port 13 …… Screw shaft 131 …… Body part 132 …… Screw blade S …… Dehydration treatment area

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area C02F 11/12 D 7824-4D

Claims (1)

[Claims] 1. A horizontally long straight cylindrical shape having a dehydration hole formed along its entire length, a side wall at the front end and a cake discharge port at the rear end,
In addition, a screw shaft equipped with spiral screw blades is rotatably pivotally attached to the filtering part, which is internally provided with gold steel, and has a tapered barrel with a large diameter from the front end to the rear end. To form a dehydration treatment area over the entire length of the filtration section, and to open a supply port in the side wall of the front end in the axial direction to form a sludge equalizing pressure feeding section including a coagulation mixing tank or a stirrer. By connecting, the floc-like sludge from the sludge equalizing pumping unit is first pressure-fed to the front part of the dehydration treatment area at the front end of the screw blade, and is fed in the axial direction of the screw blade along the lead direction. , While being held in a flocculated state on the screw blades while being supplied in a stationary state and sequentially filled to be in a semi-dewatering state at the filling pressure, the screw shaft is rotated to be dehydrated in the dehydration treatment area,
Then, the sludge or the like is characterized in that the cake is pushed out from the discharge port by pumping to the discharge port side while dehydrating in the dehydration processing region consisting of the rotating screw shaft through the front part of the dehydration processing region. Method.