JP2018103070A - Multiple rotary disk-type solid-liquid separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple rotary disk-type solid-liquid separator which, when performing dewatering treatment of sludge water having a high concentration of salts, achieves dewatered sludge having such a reduced concentration of salts as to cause no problems even if the dewatered sludge is used as cement materials, with a simple structure and at low cost.SOLUTION: In a multiple rotary disk-type solid-liquid separator, a plurality of rotating axes arranged from upstream to downstream, with a plurality of rotary disks fitted to each of the axes, are axially supported, sludge-containing water is fed from above the rotary disks in the upstream side, and liquid is eliminated and separated through gaps between the rotary disks. Thereby, dewatered sludge placed on the rotary disks is moved from upstream to downstream of the rotary disks and is discharged from a dewatered sludge discharging portion provided at the most downstream side of the rotary disks. A washing water supply device to wash the dewatered sludge on the rotary disks on the way to the dewatered sludge discharging portion is provided above the rotary disks.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a multiple turntable type solid-liquid separation apparatus for dewatering sludge water generated in a wastewater treatment process or the like in a sewage treatment plant, a human waste treatment plant, or other facilities.

  Sludge water generated in sewage treatment plants, human waste treatment plants or other industries is reduced in volume by a dehydration method represented by the following method. First, sludge water is agglomerated in advance to coarsen the sludge particles, and then sludge using a filter press, belt press, screw press, centrifugal dewatering device, vacuum pressure dewatering device or multiple-rotary disk type solid-liquid separation device, etc. A so-called dehydration treatment is performed to increase the solid concentration while discharging water in the system out of the system (see Patent Document 1).

  The water content of the dewatered sludge is 40 to 70% for inorganic sludge and 80 to 90% for organic sludge. When the performance of the dewatering treatment equipment is constant, it depends on the ratio of inorganic and organic substances contained in the sludge. The water content of the dewatered sludge obtained is influenced.

  As the final disposal of the dewatered sludge, various methods such as landfill disposal, composting, incineration, carbonization, fuelization, or use as a cement raw material are carried out in accordance with the characteristics of the contents.

However, the dehydrated sludge sometimes contains a large amount of salts, and causes various adverse effects as follows in each final disposal step. That is, when using heat as incineration at final disposal system, cause harmful effects such as increase of the SO _x and NO _x in the exhaust gas, also have harmful effects corrosion degradation of mechanical parts of the final disposal apparatus according chlorine ions Can occur. Moreover, when using as a cement raw material, there exists a possibility of causing the fall of cement quality by salt content increase. For the reasons described above, it is desired to reduce in advance the salts accompanying dewatered sludge.

Japanese Patent Laid-Open No. 2016-13556

  The present invention provides a multi-spindle type solid-liquid separation device capable of obtaining a dehydrated sludge having a reduced salt concentration with a simple structure and low cost when dewatering sludge water having a high salt concentration. For the purpose.

  The present inventors have found that a dehydrated sludge having a reduced salt concentration can be easily obtained by only slightly changing the structure of a conventionally used multiple-rotary disk type solid-liquid separator, and have reached the present invention. .

  That is, the multiple turntable type solid-liquid separation device according to the present invention supports a plurality of rotating shafts fitted with a plurality of rotating plates from the upstream side to the downstream side, and supports the sludge-containing water from above the upstream rotating plate. The dewatered sludge placed on the rotating disk is moved from the upstream side to the downstream side of the rotating disk by removing the liquid from the gap between the rotating disks and separating it, and provided on the most downstream side of the rotating disk. In the multiple turntable type solid-liquid separator that discharges from the dewatered sludge discharge section, a cleaning water supply device for cleaning the dewatered sludge on the turntable in the middle of the dewatered sludge discharge section is provided above the turntable. It consists of what is characterized by being. According to such a multiple turntable type solid-liquid separation device, the washing water supply device for washing the dewatered sludge on the turntable on the way to the dewatered sludge discharge section is provided above the turntable. The dewatered sludge in the dewatering process can be easily washed with the wash water flowing out from the wash water supply device, and the salt content in the obtained dewatered sludge can be easily reduced at a low cost.

  In this invention, it is preferable that the said sludge containing water is the sludge water by which the coagulation process was carried out. By supplying the agglomerated sludge water as sludge-containing water, dewatering efficiency can be improved.

According to the multiple rotary disk type solid-liquid separator according to the present invention, dehydrated sludge having a low salt content can be obtained from sludge water having a high salt concentration, and SO _x and NO _x generated when heat treating the dehydrated sludge. Therefore, the corrosion deterioration of the machine part can be reduced.
Moreover, since dehydrated sludge with a low salt concentration is obtained, when the obtained dehydrated sludge is used as a cement material, it is possible to prevent deterioration in quality.

It is a schematic explanatory drawing which shows the multiple turntable type solid-liquid separator which concerns on one embodiment of this invention. It is the perspective view which expanded the principal part of the multiplex turntable type solid-liquid separator of FIG. It is a schematic explanatory drawing of the multiple turntable type solid-liquid separator which concerns on the other embodiment of this invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic explanatory view showing a multiple turntable type solid-liquid separation apparatus according to an embodiment of the present invention. A coagulation tank 1, a multiple turntable type solid-liquid separation apparatus 2, and a dewatered sludge receiving tank 3 are arranged in this order. It is installed at.

  A stirrer 4 is attached to the coagulation tank 1, and one end of a sludge water discharge pipe 5 communicates with the coagulation tank 1. Reference numeral 2 denotes a multiple turntable solid-liquid separator, and reference numeral 6 denotes a housing of the multiple turntable solid-liquid separator 2. The other end of the sludge extraction pipe 5 is connected to the upper end of the housing 6, and a separation liquid discharge pipe 7 is attached to the lower end of the housing 6.

  Rotating shafts 9 fitted with a number of elliptical rotating discs 8 are arranged in the housing 6 from the upstream side to the downstream side, and are supported so as to be rotatable around the shafts. The fixing member 10 is provided horizontally.

  FIG. 2 is an enlarged perspective view of a main part of the multiple turntable type solid-liquid separation device 2. A turntable 8 is arranged between four fixed members 10, and each turntable 8 is interposed via a spacer ring 11. The rotary shaft 9 is fitted.

  The rotating directions of the respective rotating disks 8 are the same, and the adjacent rotating disks 8 are arranged so as to be rotatable without contacting each other.

  The upper portion of the housing 6 is a pressure plate 12 that is inclined from the upstream side to the downstream side. A pressure mechanism 13 is attached to the downstream side of the pressure plate 12, and the pressure plate support shaft 14 serves as a fulcrum. By moving the pressure plate 12 up and down by the pressure mechanism 13, the size of the gap between the distal end portion of the fixing member 10 and the distal end portion of the pressure plate 12 can be changed, and the gap functions as the dewatered sludge discharge portion 15. To do. The dewatered sludge 16 discharged from the dewatered sludge discharge unit 15 falls into the dewatered sludge receiving tank 3. An air cylinder or the like can be used as the pressurizing mechanism 13.

  A washing water supply device 17 for washing dewatered sludge is installed above the rotating plate 8 in the center of the large number of rotating plates 8 installed in the multiple rotating plate type solid-liquid separator 2. As the washing water supply device 17, a shower nozzle, a watering pipe, or the like can be used.

[Action]
Next, the operation of the multiple turntable type solid-liquid separator of the present invention will be described.
Sludge water containing a large amount of inorganic salt having a water content of around 98% discharged from a digested sludge treatment apparatus or the like not shown is supplied from the sludge water supply pipe 18 to the coagulation tank 1, and the organic polymer flocculant alone is used. Alternatively, both the organic polymer flocculant and the inorganic flocculant are added from the flocculant addition pipe 19, and the agitation tank 1 is agitated by the agitator 4, whereby the solid matter in the sludge water is agglomerated.

  The coagulated sludge water is supplied from the sludge water take-out pipe 5 to the upper side of the rotary disk 8 on the upstream side of the multiple rotary disk type solid-liquid separator 2.

  The agglomerated solid matter in the sludge water becomes dehydrated sludge 16 and stays on the upper part of the rotating disk 8 or the fixed member 10, and the water falls from the gap of the rotating disk 8 or the fixed member 10 to the lower part. The dewatered sludge 16 is moved from the upstream side to the downstream side of each rotating disk 8 while the dehydrated sludge 16 is placed on the upper part of the rotating disk 8 or the fixed member 10, and moisture in the dehydrated sludge is sequentially removed during this time. . Then, the dewatered sludge 16 on the upper part of the rotating disk 8 is finally discharged into the dewatered sludge receiving tank 3 as the dehydrated sludge 16 from the dewatered sludge discharge section 15 which is a gap between the fixing member 10 and the pressure plate 12.

  During the dehydration process, the washing water flows out from the washing water supply device 17 and the dewatered sludge on the rotating disk 8 is washed.

  The washing water penetrates into the dewatered sludge 16 to wash away salts, and the washing wastewater immediately falls from the gap of the rotating disk 8, so that the dewatering effect is not reduced so much, and the dewatered sludge with a relatively small amount of washing water. The salt content can be reduced.

  As the water flowing out from the washing water supply device 17, clarified water and sewage treated water can be used, and any water having an electrical conductivity of less than 3,000 μS / cm can be used.

  The sludge water with a moisture content of around 98% becomes dehydrated sludge with a moisture content of around 92% at the upper part of the rotating disk 8 in the middle of the multi-turn disk type solid-liquid separator 2 and is discharged from the dewatered sludge discharge section 15. Is dehydrated to dehydrated sludge with a moisture content of around 84%. Further, the water including the cleaning wastewater removed during this time is discharged from the discharge pipe 7.

  In addition, by driving the pressure plate 12 up and down by the pressure mechanism 13, the size of the gap between the tip of the pressure plate 12 and the tip of the fixing member 10 can be changed, and by changing the size of the gap. The moisture content of the dewatered sludge 16 discharged from the dewatered sludge discharge unit 15 can be adjusted to some extent. In other words, the moisture content of the dewatered sludge obtained decreases as the gap becomes narrower. However, the processing amount per unit time decreases as the gap is narrowed.

  FIG. 3 is a schematic explanatory view showing a multiple turntable type solid-liquid separation device according to another embodiment of the present invention, in which a rotary shaft 9 having a large number of circular turntables 8 fitted in a housing 6 is provided from the upstream side. The lower rotating disk group 20 is arranged from one corner to the other corner in the housing 6 while the upper rotating disk group 21 extends from the center to the downstream side. Is only arranged.

  In both of the turntable groups 20 and 21, the adjacent turntables 8 are in contact with each other, and the rotation direction of the turntable 8 in each turntable group is the same, but the turntable group 20 and the turntable 8 rotate. The rotating direction of the rotating disk 8 of the panel group 21 is opposite. A cleaning water supply device 17 is installed above the substantially central portion of the lower rotating disk group 20.

  Also in the multiple turntable type solid-liquid separation device 32 shown in FIG. 3, the sludge water aggregated from the sludge water take-out pipe 5 is on the upstream side of the turntable group 20 below the multiple turntable type solid-liquid separation device 32. It is supplied above the turntable 8.

  The agglomerated solid matter in the sludge water becomes dehydrated sludge 16 and stays at the upper part of the rotating disk 8, and the water falls downward from the gaps of the rotating disks 8. The dewatered sludge 16 is moved from the upstream side to the downstream side of each rotating disk 8 while the dehydrated sludge 16 is placed on the upper part of the rotating disk 8, and the water in the dewatered sludge 16 is sequentially removed during this time.

  Further, the dewatered sludge in the dewatering process on the rotating disk is washed by the wash water flowing out from the wash water supply device 17, and the salt content in the dewatered sludge 16 is lowered.

  The dewatered sludge 16 formed on the upper part of the rotating disk 8 downstream from the center part of the lower rotating disk group 20 is squeezed by each rotating disk 8 of the upper rotating disk group 21, and finally the rotating disk group 20 and the rotation. It is discharged as dehydrated sludge 16 from the dewatered sludge discharge section 15 which is a gap between the panel groups 21.

  In the description of the above two embodiments, the sludge water is coagulated in advance. However, depending on the sludge water to be treated, the coagulation process can be omitted. In addition, only one cleaning water supply device 17 is installed above the turntable 8, but when the salt concentration in the sludge water is high, two or more cleaning water supply devices 17 are installed in the running direction of the dewatered sludge 16. Also good.

  INDUSTRIAL APPLICABILITY The present invention can be widely used as a multiple turntable type solid-liquid separation device for dewatering sludge-containing water.

DESCRIPTION OF SYMBOLS 1 Coagulation tanks 2, 32 Multiple rotary disk type solid-liquid separator 3 Dewatered sludge receiving tank 4 Stirrer 5 Sludge water take-out pipe 6 Housing 7 Release pipe 8 Rotary disk 9 Rotating shaft 10 Fixing member 11 Spacer ring 12 Pressure plate 13 Pressurization Mechanism 14 Pressure plate support shaft 15 Dehydrated sludge discharge part 16 Dehydrated sludge 17 Washing water supply device 18 Sludge water supply pipe 19 Coagulant addition pipes 20 and 21

Claims (2)

A plurality of rotating shafts fitted with a plurality of rotating disks are arranged side by side from the upstream side to the downstream side, and the sludge-containing water is supplied from above the rotating disk on the upstream side to remove liquid from the gaps of the rotating plates and separate them. The multi-rotary disk type solid-liquid separation that moves the dewatered sludge placed on the rotating disk from the upstream side to the downstream side of the rotating disk and discharges it from the dewatered sludge discharge section provided on the most downstream side of the rotating disk In the device
A multiple turntable type solid-liquid separator characterized in that a washing water supply device for washing dewatered sludge on a turntable on the way to a dewatered sludge discharge section is provided above the turntable.   The multiple turntable type solid-liquid separator according to claim 1, wherein the sludge-containing water is coagulated sludge water.

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