JP2016190190A - Sludge treatment system and sludge treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sludge treatment system capable of preventing decay of a fibrous material contained in sludge, thereby stably supplying, as a dehydration auxiliary agent, the fibrous material during dehydration at an intensive treatment plant.SOLUTION: Sludge and a fibrous material are separated from each other at each local treatment plant, and are transported via separate pipelines to an intensive treatment plant. The sludge and the fibrous material are separately stored at the intensive treatment plant, and a sludge treatment, such as dehydration, is carried out by supplying the fibrous material to the sludge.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sludge treatment system and a sludge treatment method, and more particularly, to a sludge treatment system and a sludge treatment method for transferring sludge and fibrous materials separately.

  The sludge in the sewage treatment plant contains a large amount of cellulosic fibrous material derived from toilet paper. In order to stably produce a dehydrated cake with a low water content by a dehydrator, it is known that the fiber content (cellulose component) contained in the sludge is greatly affected. Since the content of the fibrous material contained fluctuates, stable dehydration cannot be performed.

  In recent years, sludge treatment in urban areas does not have sludge treatment facilities for each individual sewage treatment plant, but collects sludge from a plurality of sewage treatment plants (local) through sludge pipes and performs batch treatment at an integrated treatment plant. A method is employed (see, for example, Patent Document 1 and Patent Document 2).

  In general, in a local treatment plant, raw water flowing into a sewage treatment plant is subjected to water treatment and discharged, and sludge is sent to an intensive treatment plant in a state where primary sludge and excess sludge are mixed. The amount of sludge and sludge properties sent from a plurality of local treatment plants fluctuated, and it was sometimes difficult to perform stable sludge treatment (digestion, dehydration, etc.) at an integrated treatment plant.

  In the invention described in Patent Document 1, in a sludge treatment method for separating and dewatering sludge generated in a treatment tank of organic wastewater, cellulosic fibers are recovered from the wastewater flowing into the treatment tank, and this fiber Sludge is dehydrated by adding a minute.

  The invention described in Patent Document 2 prevents sludge from decaying when sludge is sent from each sewage treatment plant to the sludge intensive treatment plant, and generating an odor due to hydrogen sulfide in the intensive treatment plant on the receiving mud side. Is.

JP 2003-80299 A JP 2002-224663 A

  In the conventional method, the sludge properties may be extremely altered during transfer, and it may be difficult to stably produce a dehydrated cake with a low content when performing sludge treatment at an intensive treatment plant. . Specifically, as the temperature is high in summer and the transport distance is longer, the fibrous material also rots due to the effect of organic matter rot in the sludge before being transferred to the intensive treatment plant. As a result, the fiber content in the sludge is reduced and the dewaterability of the sludge is deteriorated. For example, it is necessary to administer a large amount of an expensive flocculant and dewatering aid at the front stage of the dehydrator.

  In invention of patent document 1, although the fiber part is added as a dehydration auxiliary material from the sludge generated in a sewage treatment plant, since the whole fiber part is collect | recovered from sewage, the load of a collection | recovery apparatus is large. In addition, it is usually difficult to recover only the fiber, and other perishable organic substances (food residues, etc.) will also be collected together. The fiber will also be spoiled due to the effects of organic spoilage during storage. To do.

  In the invention of Patent Document 2, it is possible to take measures against odor due to sludge decay, but it is not possible to separate and transfer fibers from the local treatment plant to the central treatment plant.

  The present invention has been made in view of the above problems, and prevents sludge of fibrous materials and individually transfers sludge and fibrous materials from a local treatment plant to an intensive treatment plant. Provided are a sludge treatment system and method capable of stably supplying a fibrous material as a dehydration aid during dehydration. In other words, fibrous materials that have a large impact on the sludge dewaterability and digestion gas production amount are transferred from the local treatment plant to the central treatment plant without being spoiled, and sludge treatment such as stable dehydration and digestion treatment is performed at the central treatment plant. It is an object of the present invention to provide a sludge treatment system and a method thereof.

  According to the first aspect of the present invention, there is provided a fibrous material separation and recovery device that separates and recovers fibrous material from sludge in at least one of the local treatment plants, and a pump for pumping the sludge from the local treatment plant to the centralized treatment plant. The sludge transport unit that is used to send the fibrous material separated and recovered by the fibrous material separation and recovery device, the fibrous material transport unit that sends the local processing plant to the central processing plant, and the central processing plant, It has a sludge treatment apparatus which mixes the fibrous material sent by the said fibrous material conveyance part with the sludge sent by the sludge conveyance part, and sludge-treats this mixed thing.

  According to a second aspect of the present invention, in the sludge treatment system according to the first aspect, the aggregate treatment plant is provided with a fibrous material storage unit for storing the fibrous material sent by the fibrous material conveying unit. The sludge treatment device mixes the fibrous material stored in the fibrous material storage unit with the sludge sent by the sludge transport unit, and sludges the mixed material. It is comprised by these.

  The invention according to claim 3 is the sludge treatment system according to claim 2, wherein the concentration of the fibrous material for measuring the concentration of the fibrous material in the sludge sent by the sludge transport unit at the aggregation treatment plant. When the concentration of the fibrous material is lower than a predetermined value as a result of measurement by the fibrous material concentration measuring unit, the fibrous material stored in the fibrous material storage unit is mixed. The mixed product is configured to be sludge treated with the sludge treatment apparatus.

  The invention according to claim 4 is the sludge treatment system according to any one of claims 1 to 3, wherein the sludge treatment device is a dehydration treatment device for dehydrating the mixed material, and the mixing. It is characterized by comprising at least one of digestion processing apparatuses for digesting processed products.

  According to a fifth aspect of the present invention, there is provided a fibrous material separation and recovery step for separating and recovering fibrous material from sludge at at least one of the local treatment plants, and a pump for pumping the sludge from the local treatment plant to the centralized treatment plant. The sludge transporting step to send using, the fibrous material separated and recovered in the fibrous material separation and recovery step, the fibrous material transporting step to send from the local treatment plant to the aggregation processing plant, and the aggregation processing plant, A sludge treatment step of mixing the fibrous material sent in the fibrous material conveyance step with the sludge sent in the sludge conveyance step, and sludge treating the mixed material.

  The invention according to claim 6 is the sludge treatment method according to claim 5, wherein the aggregate treatment plant executes a fibrous material storage step for storing the fibrous material sent in the fibrous material conveyance step. The sludge treatment step is configured to mix the fibrous material stored in the fibrous material storage step with the sludge sent in the sludge transporting step, and sludge the mixed material. It is characterized by.

  The invention according to claim 7 is the sludge treatment method according to claim 6, wherein the concentration of the fibrous material for measuring the concentration of the fibrous material in the sludge sent in the sludge conveying step in the aggregation treatment plant. As a result of executing the measurement step and measuring the fibrous material concentration measurement step, the fibrous material stored in the fibrous material storage step is mixed when the concentration of the fibrous material is lower than a predetermined value. The mixed material is configured to be sludge treated in the sludge treatment step.

  The invention according to claim 8 is the sludge treatment system according to any one of claims 5 to 7, wherein the sludge treatment step is a dehydration treatment step of dehydrating the mixed one, and the mixing It is characterized by comprising at least one of digestion processing steps for digesting the processed product.

  According to the present invention, the fibrous material having a great influence on the dewaterability is recovered from the sludge before being spoiled and added to the sludge of the intensive treatment plant as a sludge treatment aid. Therefore, it is necessary to purchase a sludge treatment aid separately. In addition, there is an effect that transportation costs, inventory management, storage space, and the like are unnecessary.

  In addition, the fiber concentration in the sludge supplied to the dehydrator can be constantly maintained at a constant level, and the sludge can be stably reformed to produce a dehydrated cake having a low water content. And since the dehydrated cake of low moisture content is produced | generated stably, the running cost for transport and disposal of a dehydrated cake can be reduced.

  Furthermore, when a fibrous material is added to the digestion tank, the amount of digestion gas produced can be increased. The energy recovered from the sewage treatment plant will increase, contributing to in-house power generation at the sewage treatment plant or energy supply to surrounding facilities.

It is the schematic which shows the outline of a sludge processing system. It is a flowchart which shows operation | movement of the sludge processing method.

  As shown in FIG. 1, the sludge treatment system 1 according to the present embodiment includes, for example, a plurality of local treatment plants 3, 4, 5, fibrous material separation and recovery devices 3 </ b> A, 4 </ b> A, 5 </ b> A, a sludge transport unit 12, 14, 16, a fibrous material transfer unit 13, 15, 17, and an aggregation treatment plant 2 in which a sludge treatment device (for example, a digestion treatment device (digestion tank) 2D or a dehydration treatment device 2A) is provided. It is configured. Note that the digestion processing device 2D and the dehydration processing device 2A may have at least one of them.

  Each of the fibrous material separation / recovery devices 3A, 4A, 5A is installed in each of the local treatment plants 3, 4, 5 separated from each other. In the fibrous material separation / recovery device 3A, a sewer pipe or the like is used from the home. The fibrous material is separated and collected from the collected sludge.

  In the fibrous material separation and recovery apparatus 3A, the fibrous material is separated and recovered from a part of the sludge. However, the fibrous material may be separated and recovered from the entire sludge.

  The sludge transport unit 12 transports sludge from the local processing plant 3 to the central processing plant 2. More specifically, the sludge transport unit 12 is configured to collect the sludge from which the fibrous material is collected by the fibrous material separation and recovery device 3A (if the fibrous material is collected from some sludge, the fibrous material is collected. (Including the sludge that was not present) is sent from the local treatment plant 3 to the centralized treatment plant 2 using the pressure feed pump P1 and the sludge carrying pipe 6. In addition, what was used conventionally is used as it is as the sludge conveyance piping 6 and the pressure feed pump P1.

  Similarly to the sludge transport unit 12, each sludge transport unit 14 and 16 transports sludge from the local treatment plants 4 and 5 to the intensive treatment plant 2, and each of the fibrous material separation and recovery devices 4A and 5A The sludge from which the fibrous material has been collected is sent from the local treatment plants 4 and 5 to the central treatment plant 2 by using the pressure pumps P3 and P5 and the sludge transfer pipes 8 and 10, respectively.

  The fibrous material transfer unit 13 is configured to transfer the fibrous material separated and recovered by the fibrous material separation and recovery device 3A from the local processing site 3 to the aggregation processing site 2, for example, a pumping pump P2 and sludge transfer pipes 6, 8, 10 is sent using a fibrous material transfer pipe 7 different from 10.

  Similarly to the fibrous material conveying unit 13, the fibrous material conveying units 15 and 17 also receive the fibrous material separated and collected by the fibrous material separating and collecting devices 4A and 5A, respectively, in the local processing plants 4 and 5. To the central processing station 2 using, for example, the pumps P4 and P6 and the fibrous material transport pipes 9 and 11 different from the sludge transport pipes 6, 8, 10, and 7, respectively. It has become.

  In the intensive treatment plant 2, using the sludge treatment apparatus, the fibrous material sent by the fibrous material transport units 13, 15, and 17 to the sludge sent by the sludge transport units 12, 14, and 16. Is mixed, and the mixed product is treated with sludge.

  For example, using the dewatering apparatus 2A in the intensive treatment plant 2, the fibrous material sent by the fibrous material transport units 13, 15, 17 to the sludge sent by the sludge transport units 12, 14, 16 The mixture is mixed, and the mixture is dehydrated (immediately; for example, before the decay of the fibrous material begins to impair the function of ensuring the dehydrating property of the fibrous material).

  As described above, the fibrous material is separated and recovered from the sludge at each of the local treatment plants 3, 4 and 5, and the sludge is sent from each of the local treatment plants 3, 4, 5 to the central treatment plant 2 using the pumps P1, P3, and P5. The sludge sent from the local treatment plants 3, 4 and 5 to the central treatment plant 2 and sent from the local treatment plants 3, 4 and 5 to the central treatment plant 2 In addition, since the fed fibrous material is mixed and the mixed material is dehydrated, a dehydrated cake having a low water content can be stably produced.

  That is, even if the sludge sent from each local treatment plant 3, 4, 5 to the central treatment plant 2 rots, the fibrous material sent from each local treatment plant 3, 4, 5 to the central treatment plant 2 rots. Never do. And after adding the fibrous material (fibrous material that guarantees the dehydration function) sent to the intensive treatment plant 2 to the sludge sent to the intensive treatment plant 2, the dehydration process is performed immediately, so the water content is low. Rate dehydrated cake can be produced stably.

  As described above, a digestion processing apparatus 2D may be provided in place of or in addition to providing the dehydration processing apparatus 2A in at least a part of the aggregation processing sites 2. Then, instead of or in addition to dehydrating the mixed material using the dehydrating device 2A, the mixed material is digested by the digesting device 2D in the intensive treatment facility 2. May be. The digestion process is a process performed to stabilize and reduce sludge by the action of anaerobic microorganisms.

  In the case where the dehydration treatment apparatus 2A and the digestion treatment apparatus 2D are provided in the central processing place 2, the digestion treatment apparatus 2D is first digested, and the digestion process is performed on the water treatment apparatus 2A. To do.

  Further, in the sludge treatment system 1, the aggregate treatment plant 2 is provided with a fibrous material storage unit 2B that (temporarily) stores the fibrous materials sent by the fibrous material conveying units 13, 15, and 17. In addition, the dewatering treatment apparatus 2A mixes the fibrous material stored in the fibrous material storage unit 2B with the sludge sent by the respective sludge transport units 12, 14, and 16, and the mixed material is mixed with the above. Sludge treatment (dehydration treatment, digestion treatment) is designed. Thereby, the fibrous material can be supplied to the sludge treatment apparatus (dehydration treatment apparatus 2A, digestion treatment apparatus 2D) in a stable manner.

  Further, in the sludge treatment system 1, the aggregate treatment site 2 is provided with a fibrous substance concentration measuring unit 2 </ b> C that measures the concentration of the fibrous substance in the sludge sent by each sludge transport unit 12, 14, 16. . And when the density | concentration of a fibrous material is lower than a predetermined value as a result of measuring with 2C of fibrous substance density | concentration measurement parts, the fibrous substance stored in the fibrous substance storage part 2B is mixed, and this mixing is carried out. The above-mentioned sludge treatment (dehydration treatment, digestion treatment) is performed. Thereby, a dehydration process and a digestion process can be performed in the stable aspect in the sludge process apparatus (Dehydration process apparatus 2A, digestion process apparatus 2D).

  Further, as described above, in at least one of the intensive treatment plants 2, the fibers sent by the fibrous material transfer units 13, 15, and 17 to the sludge sent by the sludge transfer units 12, 14, and 16, respectively. The mixture is mixed and the mixture is digested immediately (for example, before the function of securing the organic property of the fibrous material is impaired by the start of the decay of the fibrous material). It has become.

  As described above, the fibrous material is separated and recovered from the sludge at each of the local treatment plants 3, 4 and 5, and the sludge is sent from each of the local treatment plants 3, 4, 5 to the central treatment plant 2 using the pumps P1, P3, and P5. The sludge sent from the local treatment plants 3, 4 and 5 to the central treatment plant 2 and sent from the local treatment plants 3, 4 and 5 to the central treatment plant 2 In addition, since the fed fibrous material is mixed and the mixed material is digested, a large amount of digestion gas can be stably generated by anaerobic fermentation of organic matter.

  That is, even if the sludge sent from each local treatment plant 3, 4, 5 to the central treatment plant 2 rots, the fibrous material sent from each local treatment plant 3, 4, 5 to the central treatment plant 2 rots. Never do. And after adding the fibrous material (fibrous material that guarantees organicity) sent to the intensive treatment plant 2 to the sludge sent to the intensive treatment plant 2, the digestion treatment is carried out immediately after mixing. Digestion gas can be generated stably.

  Further, in the sludge treatment system 1, the aggregate treatment plant 2 is provided with a fibrous material storage unit 2B that (temporarily) stores the fibrous materials sent by the fibrous material conveying units 13, 15, and 17. The digester 2D mixes the fibrous material stored in the fibrous material storage unit 2B with the sludge sent by the sludge transport units 12, 14, 16 and digests the mixed material. It comes to handle. Thereby, a fibrous material can be supplied to the digestion processing apparatus 2D in a stable manner.

  Further, in the sludge treatment system 1, the aggregate treatment site 2 is provided with a fibrous substance concentration measuring unit 2 </ b> C that measures the concentration of the fibrous substance in the sludge sent by each sludge transport unit 12, 14, 16. . And when the density | concentration of a fibrous material is lower than a predetermined value as a result of measuring with 2C of fibrous substance density | concentration measurement parts, the fibrous substance stored in the fibrous substance storage part 2B is mixed, and this mixing is carried out. The food is digested by the digestion processing apparatus 2D. Thereby, a predetermined amount of digestion gas can be generated in a stable manner in the digestion apparatus 2D.

  Here, the operation of the sludge treatment system 1 will be described with reference to FIG.

  In the above operation, the fibrous material separation and recovery step (step SA01) for separating and recovering the fibrous material from the sludge at each of the local treatment plants 3, 4, and 5 (the fibrous material was recovered in the fibrous material separation and recovery step) ) Sludge transporting process (step SA02) for sending sludge from each local treatment plant 3, 4, 5 to the centralized treatment plant 2 using each pumping pump P1, P3, P5 and each sludge transporting pipe 6, 8, 10. The fibrous materials separated and recovered in the fibrous material separation and recovery step are transferred from the local treatment plants 3, 4, 5 to the central treatment plant 2, for example, the pressure pumps P2, P4, P6, and the sludge conveyance pipes. It is sent in the sludge transporting process at the fibrous material transporting process (step SA03) to be sent using each of the fibrous material transporting pipes 7, 9, 11 other than 6, 8, 10 and the aggregation processing site 2. The fibrous form sent to the sludge in the fibrous material transport process It was mixed, those which are the mixture (immediately; for example, before the function of the start of the decay of fibrous materials to ensure the dewatering of the fibrous material is damaged) a sludge treatment process of sludge treatment.

  The sludge treatment process includes at least one of a dehydration process (step SA04) and a digestion process (step SA05).

  The dehydration process (step SA04) is a process of dehydrating the above-mentioned mixture, and the digestion process (step SA05) is a process of digesting the above-mentioned mixture.

  When the sludge treatment process is composed of a dehydration process (step SA04) and a digestion process (step SA05), the digestion process is first performed in the digestion process (step SA05), and the digested process is performed. Dehydration is performed in the dehydration process (step SA04).

  In the sludge treatment method of the sludge treatment system 1, the aggregate treatment plant 2 executes a fibrous material storage step (temporarily) for storing the fibrous material sent in the fibrous material conveyance step, and the dehydration treatment step. Mixes the sludge sent in the sludge transporting process with the fibrous material stored in the fibrous material storage process, dehydrates this mixture, and the digestion process sends it in the sludge transporting process. The sludge that has been mixed with the fibrous material stored in the fibrous material storage step is digested. These operations can be grasped as a sludge treatment method.

  Further, in the sludge treatment method, the intensive treatment plant 2 executes a fibrous substance concentration measuring step for measuring the concentration of fibrous substances in the sludge sent in the sludge conveying step, and the measurement is performed in the fibrous substance concentration measuring step. As a result, when the concentration of the fibrous material is lower than the predetermined value, the fibrous material stored in the fibrous material storage step is mixed, and this mixed product is dehydrated and digested in the dehydration processing step. At least one of digestion treatment is performed in the treatment step.

  In the above description, the fibrous material is transferred by the fibrous material conveying units 13, 15, and 17. However, instead of using the fibrous material conveying pipes 7, 9, and 11, the fibrous material separating and collecting device is used. The fibrous material separated and recovered in (1) may be transferred from each of the local treatment plants 3, 4 and 5 to the aggregation treatment plant 2 by a vehicle or the like (for example, a truck). This eliminates the need to provide new piping.

  Alternatively, only some of the local processing plants (for example, only 3) may be transported separately, and the remaining local processing plants (4, 5) may be transported in a mixed state.

  The present invention is not limited to the embodiments of the invention described above, and can be implemented in other modes by making appropriate modifications.

DESCRIPTION OF SYMBOLS 1 Sludge processing system 2 Aggregate treatment plant 2A Dehydration processing device 2B Fibrous material storage unit 2C Fibrous material concentration measurement unit 3, 4, 5 Local treatment plant 3A, 4A, 5A Fibrous material separation and recovery device 12, 14, 16 Sludge Conveyance unit 13, 15, 17 Fibrous material conveyance unit P1, P3, P5 Pressure feed pump

Claims (8)

A fibrous material separation and recovery device for separating and recovering fibrous material from sludge in at least one of the local treatment plants;
A sludge transport unit that sends the sludge from the local treatment plant to the central treatment plant using a pressure pump;
A fibrous material transport unit that sends the fibrous material separated and recovered by the fibrous material separation and recovery device from the local processing plant to the aggregation processing plant;
In the intensive treatment plant, the sludge sent in the sludge transport unit is mixed with the fibrous material sent in the fibrous material transport unit, and the sludge treatment device that performs sludge treatment on the mixed material,
A sludge treatment system characterized by comprising: In the sludge treatment system according to claim 1,
The aggregate treatment plant is provided with a fibrous material storage unit for storing the fibrous material sent by the fibrous material conveyance unit,
The sludge treatment apparatus is configured to mix the sludge sent in the sludge transport unit with the fibrous material stored in the fibrous material storage unit, and sludge the mixed material. A sludge treatment system characterized by In the sludge treatment system according to claim 2,
In the intensive treatment plant, it has a fibrous substance concentration measuring unit that measures the concentration of fibrous substances in the sludge sent by the sludge transport unit,
As a result of measurement by the fibrous substance concentration measurement unit, when the concentration of the fibrous substance is lower than a predetermined value, the fibrous substance stored in the fibrous substance storage unit is mixed and mixed. The sludge treatment system is configured to treat sludge with the sludge treatment apparatus. In the sludge treatment system according to any one of claims 1 to 3,
The sludge treatment system is constituted by at least one of a dehydration treatment device for dehydrating the mixed material and a digestion treatment device for digesting the mixed material. A fibrous material separation and recovery step of separating and recovering fibrous material from sludge in at least one of the local treatment plants;
A sludge conveying step for sending the sludge from the local treatment plant to the central treatment plant using a pressure pump;
A fibrous material conveying step of sending the fibrous material separated and recovered in the fibrous material separation and recovery step from the local processing plant to the aggregated processing plant;
In the intensive treatment plant, the sludge sent in the sludge transporting step is mixed with the fibrous material sent in the fibrous material transporting step, and the mixed sludge treatment step for sludge treatment,
The sludge processing method characterized by including. The sludge treatment method according to claim 5,
In the aggregation processing plant, a fibrous material storing step for storing the fibrous material sent in the fibrous material conveying step is executed,
The sludge treatment step is configured to mix the fibrous material stored in the fibrous material storage step with the sludge sent in the sludge transporting step, and sludge the mixture. A sludge treatment method characterized by comprising: The sludge treatment method according to claim 6,
In the intensive treatment plant, execute a fibrous substance concentration measuring step for measuring the concentration of fibrous substances in the sludge sent in the sludge conveying step,
As a result of measurement in the fibrous substance concentration measurement step, when the concentration of the fibrous substance is lower than a predetermined value, the fibrous substance stored in the fibrous substance storage step is mixed and mixed. The sludge treatment method is characterized in that sludge treatment is performed in the sludge treatment step. In the sludge treatment system according to any one of claims 5 to 7,
The sludge treatment step is constituted by at least one of a dehydration treatment step for dehydrating the mixed material and a digestion treatment step for digesting the mixed material.

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