TW200306955A - Method and apparatus for treating organic wastewater capable of recovering phosphorus - Google Patents

Abstract

The present invention provides a method and a device for treating residual sludge by which not only the discharge quantity of residual sludge may be reduced, but also the removal of phosphorus from sludge is feasible. Further, the present also provides a method and an apparatus for biologically treating an organic wastewater wherein a sludge treating system is installed. The method for treating residual sludge in the present invention is to treat the residual sludge produced from a treating process of organic wastewater consisting of biological treatment process and a solid-liquid separating process characterized by that a part or all of the residual sludge is concentrated to produce an effluent and a concentrated sludge, the effluent is then treated to recover phosphorus and returned to the biological treating process, or discharged as a treated water to the outside of system, meanwhile, the produced concentrated sludge is subjected to an ultrasonic treatment and then returned to the biological treating process.

Description

200306955 V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a technology for reducing the amount of excess sludge produced during the biological treatment of sewage or organic industrial wastewater. . [Previous technology] Generally speaking, sewage or organic industrial wastewater is treated by aerobic biological treatment, denitrification, and anaerobic biological treatment. Although the biological treatment method of organic wastewater is very good, a large amount of sludge is generated during the treatment process, and the amount of sludge produced in Japan is more than 10 million people per year. Generally speaking, the remaining sludge is buried or incinerated after dehydration, but the cost of this treatment increases year by year, which is one of the reasons for the increase in the overall cost of wastewater treatment. Therefore, in recent years, technologies for reducing the amount of excess sludge generated have attracted attention. For example, some methods have suggested that the remaining sludge is irradiated with ultrasound to destroy the cell membranes of microorganisms in the remaining sludge, and the contents are converted into liquefied organic matter, and then the liquefied organic matter is returned to the biological treatment tank, and the liquefied organic matter is biologically processed to make the liquefied organic matter. Inorganicization to reduce excess sludge. However, the inventors of the present application conducted experiments on the above-mentioned treatment method of residual sludge based on ultrasound, and found that although the inorganicization of organic matter was achieved with the liquefaction of sludge, at the same time, the phosphorus in the sludge became soluble due to the liquefaction treatment. However, phosphorus cannot be removed in the biological treatment tank, and thus it becomes an obvious problem that the treated water containing high concentration of phosphorus is discharged outside the system. The present invention was created to solve the above problems, and an object of the present invention is to provide not only a reduction in the discharge amount of excess sludge, but also

314708.ptd page 7 200306955. V. Ming Ming explained (2) Technology for removing walls from the remaining sludge at the same time. [Summary of the Invention] The present inventors have found the following processing methods and devices as a means for solving the above problems. 1. An organic wastewater treatment method capable of recovering phosphorus, in the process of treating organic wastewater composed of a biological treatment process and a solid-liquid separation process, the remaining sludge generated is treated, and is characterized by: Part or all of the sludge generates a release liquid and concentrated sludge, and then the generated detachment liquid is subjected to phosphorus recovery treatment and sent back to the biological treatment process or discharged to the system as treated water. At the same time, Ultrasonic treatment is performed on the concentrated sludge generated by the concentration of the remaining sludge, and it is returned to the biological treatment process. 2. As in the method of item 1 above, the phosphorus recovery treatment of the above-mentioned dehydration liquid is performed by adding a coagulant to condense and precipitate phosphate ions in the above-mentioned dehydration liquid, and thereby separating and removing phosphorus from the liquid. . 3. As in the method of item 1 above, the phosphorus recovery treatment is performed on the above-mentioned leaching solution by adding ammonia ions (A mm ο nium I ο η) and osmosis to the above-mentioned leaching solution, or by adding calcium In the above-mentioned detachment solution, maintaining the threshold value of the detachment solution at 9 or more, the packing crystals are precipitated, and the method is performed by separating and removing phosphorus from the liquid. 4. A method for treating organic wastewater, which is characterized in that: biological treatment of organic wastewater is performed in a biological treatment tank, and then solid-liquid separation is performed on the activated sludge mixed liquid discharged from the biological treatment tank to generate precipitated sludge and treat it Water and concentrate part or all of the remaining sludge

314708 ptd Page 8 200306955 V. Description of the invention (3) Liquid and concentrated sludge, and then the phosphorus generated from the separated liquid is recovered and sent back to the biological treatment process or discharged out of the system as treated water. At the same time, the concentrated sludge generated by the concentration of the remaining sludge is subjected to ultrasonic treatment and returned to the biological treatment process. 5. The method according to item 4, wherein the phosphorus recovery treatment of the dissociating solution is performed by adding a coagulant to agglomerate and precipitate phosphate ions in the dissociating solution, and separating and removing phosphorus from the liquid. 6. The method according to item 4, wherein the phosphorus recovery treatment of the release liquid is by adding ammonium ions and magnesium to the release liquid, or by adding # 5 to the release liquid and maintaining the release liquid. The pH value is 9 or more, and the phosphorus crystals are precipitated, which is performed by separating and removing phosphorus from the liquid. 7. An organic waste water treatment device for a recyclable wall is used to treat the remaining sludge generated during the treatment of organic waste water consisting of a biological treatment process and a solid-liquid separation process, which is characterized by: A sludge concentrator that concentrates a part or all of the remaining sludge to produce detachment and concentrated sludge; a phosphorus recovery tank that performs phosphorus recovery treatment on the effluent generated by the sludge concentrator; An ultrasonic treatment device for ultrasonic treatment of the generated concentrated sludge; and a pipe for returning the sludge processed by the ultrasonic treatment device to the biological treatment process. 8. The device according to item 7, including a pipe for returning the processing liquid processed in the phosphorus recovery tank to the biological processing process. 9. An organic wastewater treatment device, comprising: a biological treatment tank for receiving organic wastewater for biological treatment; and a biological treatment tank

Page 9 314708.ptd 200306955 _V. I. Note (4) Solid-liquid separation device for solid-liquid separation of the discharged activated sludge mixed liquid to generate precipitated sludge and k-water; concentration A part or all of the discharged sediment sludge, and a sludge concentrator that generates detached liquid and concentrated sludge; a phosphorus recovery tank that performs phosphorus recovery treatment on the detached liquid generated by the sludge thickener; Ultrasonic treatment device for ultrasonic treatment of the generated concentrated sludge; and piping for returning the sludge treated by the ultrasonic treatment device to the biological treatment tank. 10. The device according to item 9, wherein the processing liquid processed by the phosphorus recovery tank is returned to the pipe of the biological processing tank. • Embodiment] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. -Fig. 1 is a schematic diagram showing a processing flow in which an ultrasonic reaction process and a phosphorus recovery process are set up on a system for treating the remaining sludge discharged during the biological treatment of organic wastewater, following the method of the present invention. The organic wastewater 1 is supplied to a biological treatment tank 2 and the organic matter in the organic wastewater 1 is inorganicized by biological treatment according to activated sludge. Here, the biological treatment tank 2 may be a biological treatment tank used in these technologies, such as a standard activated sludge method, an anaerobic and aerobic method, a nitrification and denitrification method, or a biofilm method. * The activated sludge mixture 3 discharged from the biological treatment tank 2 is supplied to the solid-liquid • Isolation device 4 (such as a sedimentation tank) and separated into treated water 5 and sedimentation sludge 6. Although the settled sludge 6 is sent back to the biological treatment tank 2 as the return sludge 7, at least a part of the return sludge 8 is also supplied to the sludge thickener 1 1 and separated into the concentrated sludge 1 2 and the release liquid 1 7 . In addition, a phosphorus release tank 9 may be provided as the front stage of the sludge concentrator 11, for example, by stirring in an anaerobic state,

3147〇8.pid Page 10 200306955 V. Description of the invention (5) The polyacid acid (P〇1 yph〇sph 〇ric A cid) in the sludge is released to enhance the detachment sent to the phosphorus recovery process 18 Phosphorus concentration in solution 17. In this case, a part of the organic wastewater 1 may be supplied to the phosphorus release tank 9. Once a part of the organic waste water 1 is supplied to the phosphorus release tank 9, the bacteria that have absorbed phosphorus will in turn adsorb the organic matter and release phosphorus, which is preferable. The release liquid 17 discharged from the sludge thickener is supplied to the phosphorus recovery process 18. In the phosphorus recovery process 18, the MAP method of forming Magnesium Ammonium Phosphate (hereinafter also referred to as "MAP") particles by adding ammonium ions and magnesium ions, or adding # 5 and maintaining the pH at 9 or more to form Hydroxy Apatite (hereinafter also referred to as "HAP") HAP method temple is known in the technology of dish recovery method to solidify and separate the dissolution in the dissolving solution 17 Sexual stone was recovered as scale containing crystals of 20%. The treatment liquid 19 after the wall is separated and recovered is sent back to the biological treatment tank 2. In the case where the recovered treatment liquid 19 has a very low phosphorus concentration or organic concentration 'and meets the discharge standard, it can be discharged to the outside of the system as treated water. On the other hand, the concentration obtained from the sludge thickener 1 丨 is applied to the ultrasonic treatment tank 13 to perform ultrasonic treatment. = The concentration of the concentrated sludge 12 supplied to the ultrasonic treatment tank 13 is used to increase the amount of liquefaction 0 to obtain highly efficient liquefied sludge. Therefore, the concentration of the clever mud in the sludge thickener u is preferably concentrated to 1 To 丨 0%, more preferably to 4 to 8%. In addition, the energy consumption of the ultrasonic vibrator used in the ultrasonic processing tank 13 is preferably in the range of 0 to 400 kj / L for the amount of liquid to be processed. In addition, the unit section of the ultrasonic emission angle is Area of energy consumption, most

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Page 11 200306955, V. Description of the invention (6) It is better than 30 w / cm2. The ultrasound-treated sludge 14 flowing out of the ultrasound-treatment tank 1 3 is returned to the bio-treatment tank 2. Like the cyclic nitrification and denitrification method, when the denitrification tank is included in the biological treatment tank, the dissolved organic matter contained in the ultrasonic treatment sludge 14 can be used as an oxygen element donor for the denitrification reaction. Utilization, so the method of supplying the ultrasonic treatment sludge 14 to the denitrification tank can be an effective method for treating organic wastewater. Hereinafter, the present invention will be specifically described using examples. The invention is not limited to this embodiment. # 施 例 1 Figure 2 shows the method used in this example. The method of the present invention: to treat the remaining sludge generated during the biological treatment of organic wastewater, and implement the sludge reduction and phosphorus recovery process. . In this embodiment, a nitrification denitrification tank composed of a denitrification tank 31 and a nitrification tank 32 is adopted as the biological treatment tank 2, and sewage is used as an organic wastewater 1. At a flow rate of 10 m 3 / d, the sewage is supplied to the denitrification tank 31 of the biological treatment tank 2. The concentration of activated sludge in the biological treatment tank 2 is about 3 0 0 0 0 m g—SS / L. The activated sludge mixed liquid from the nitrification tank 32 of the biological treatment tank 2 is supplied to the solid-liquid separation device 4. In this embodiment, a sedimentation tank is used as the solid-liquid separation device 4 to separate the activated sludge mixed liquid into treated water 5 and sedimentation sludge 6. The flow rate of the return sludge 7 from the sedimentary sludge 6 discharged from the solid-liquid separation device 4 is 4 m 3 / d, and the sludge concentration is about 10,000 m g-SS / L. Among them, 3.36m V d is returned to the biological treatment tank 2 as the return sludge 7, and the remaining 0.6 4 m 3 / d is supplied to the phosphorus release tank 9 as the treated sludge 8. And mixed with a part of the organic wastewater 1 0.5 m V d.

314708 ptd page 12 200306955 V. Description of the invention (7) In the stone chute release tank 9, the polyphosphoric acid in the sludge is discharged under anaerobic energy. Then, the phosphorus is released into the sludge concentrator 1 1 and separated into the release fluid. 7 and the 5 sludge supply sludge 1 2 has a sludge concentration of 5%. For '-Dagger 1 2. > Dehydration liquid I · 13m Vd ° 18 obtained from the sludge concentrator 11. In the phosphorus recovery process 18 in Example 1, go to the seventh and the disc recovery process field τ,> Poly Alununum Chlonde 'PAC is not added in the release solution ^, as an energy agent, by condensing phosphorus And deposited from the liquid, horses agglutinate 2g / L of PAC after the release liquid 17, it is like the first one, the phosphate is not the same as that of the water, the phosphate ion of the treated water is 19 Concentration was reduced to 〇R 凡 · bmS / L. In addition, it is also good treated water with an SS of 1 mg / L or less, which is not in the range of μ million. u This is directly discharged to the first table: the sludge concentrated release solution i 7 and the phosphorus recovery 6 Tian Rongshui 19 in Example 1 the nature of the liquid phosphorus recovery P04-P (mg / L) 40 I · -------- --- 'J, 0.5 SS (mg / L) 45-< 1 The concentrated sludge 1 2 obtained from the sludge thickener 1 1 is supplied to the ultra The sonic reaction tanks 1 and 3 perform ultrasonic processing. The actual power consumption of the ultrasonic transmitter used in the ultrasonic reaction tank 丨 3 is 700 w (the amount of power: 1.8 kw h a day). In addition, the irradiation intensity per sludge amount was 50 kj / l. Ultrasonic-treated sludge 1 4 is returned to the biological treatment tank 2 and the denitrification tank 3

314708.ptd Page 13 200306955 _V. Description of the invention (8) The second table shows the properties of the concentrated sludge 12 before the ultrasonic treatment and the sludge 14 after the ultrasonic treatment in the process of Example 1. As can be seen from Table 2, in this embodiment, compared with the stage before the ultrasonic treatment, the soluble components of the sludge 14 after the ultrasonic treatment are increased, and the sludge is also liquefied. Table 2: Properties of the returned sludge and ultrasonic treated sludge in Example 1 Returned sludge Ultrasonic treated sludge SS (mg / L) 50000 — CODCr (mg / L) 46700 — S-CODCr (mg / L) 20 2300

S-CODCr: solubility COD: Table 3 shows the water quality of the treated water 5 of the biological treatment system of the combined case of the remaining sludge treatment of the present invention in Example 1. As can be seen from Table 3, in this example, good treated water quality with SS of 10 mg / L and CODCr of 30 mg / L was obtained. In addition, a full fill of 0.5 m g / L can also be obtained with good water quality. Table 3: Water quality of sewage and treated water in Example 1 SS (mg / L) 66 8 CODCr (mg / L) 300 28 S-CODCr (mg / L) 190 16 Total nitrogen (mg / L) L) 27 7 Full fill (mg / L) 3.5 0.5

314708.ptd Page 14 200306955 V. Description of the Invention (9) Figure 3 shows the change in the amount of sludge in the biological treatment tank 2 during the combined biological treatment of the remaining sludge treatment in this embodiment. Under continuous operation for about 60 days, the amount of sludge in the biological treatment tank 2 is stably maintained at about 10 kg. Therefore, it can be known that the amount of excess sludge can be reduced by the excess sludge treatment of the present invention. . Embodiment 2 In this embodiment, as in Embodiment 1, a system as shown in FIG. 2 is used as the phosphorus recovery process 18 to perform phosphorus recovery according to the HAP method. Sewage is used as organic wastewater 1 and the sewage is supplied to biological treatment tank 2 denitrification tank 31 at a flow rate of 10 m V d. The activated sludge concentration in the biological treatment tank 2 is about 300 mg-SS / L. The activated sludge mixed liquid from the nitrification tank 32 of the biological treatment tank 2 is supplied to the solid-liquid separation device 4. In this embodiment, as in Embodiment 1, a sedimentation tank method is adopted as the solid-liquid separation device 4, and the activated sludge mixture 3 is separated into treated water 5 and sedimentary sludge 6. The flow rate of the precipitated sludge 6 discharged from the solid-liquid separation device 4 was 4 m 3 / d, and the sludge concentration was about 1,000 mg-SS / L. Among them, 3.36 m3 / d is returned to the denitrification tank 3 1 of the biological treatment tank 2 as the return sludge 7 and the remaining 0.6 4 m 3 / d is supplied to the phosphorus release tank 9 to do 5m3 / d 混。 For the treated sludge 8, and a part of the organic wastewater 1 0. 5m3 / d mixed. In the phosphorus release tank 9, the same treatment as in Example 1 was also performed to release the polyphosphoric acid in the sludge. The sludge treated in the phosphorus release tank 9 is then supplied to a sludge concentrator 11 and separated into a release liquid 17 and a concentrated sludge 12. The sludge concentration of the concentrated sludge 12 was 5%, and the volume of the concentrated sludge was 0.1 3 m 3 / d. The separated liquid 17 obtained from the sludge thickener 11 is supplied to a phosphorus recovery process.

314708.ptd Page 15 200306955 k V. Description of the Invention (ίο) 1 8. In the phosphorus recovery process 18 in Example 2, a cylinder filled with phosphate rock was used as the scale recovery process 18, and slaked lime (hydroxide) was added to the release solution 17 to adjust the alkalinity and calcium. The supply of 'P' as HAP: Ca50H (P04) straw crystallized, and deposited and separated for phosphorus recovery according to the HAP method. Table 4 shows the water quality of the sludge concentrating and removing liquid 17 in the phosphorus recovery process 18 and the treated water 19 after the phosphorus recovery is completed. As can be seen from Table 4, in the phosphorus recovery process 18, the dissolved phosphorus was separated from the sludge concentration and separation solution 17 and the soluble phosphorus was separated and removed. The treatment liquid 19 after the phosphorus recovery is discharged directly to the outside of the system. Table H 4: The sludge concentrating and removing liquid 17 and the treated water recovered from phosphorus in Example 2 9 The properties of the treated liquid P 4 -P (mg / L) 36 0.4 PH 7.2 8.1 „All the concentrated sludges 12 obtained in the sludge thickener 11 are supplied to the ultrasonic reaction tank 13 and subjected to ultrasonic treatment under the same conditions as in Example 1. The sludge 1 after ultrasonic treatment 4 Return to the denitrification tank of the biological treatment tank 2

Table 5 shows the properties of the concentrated sludge 12 before the ultrasonic treatment and the sludge 14 after the ultrasonic treatment during the treatment in Example 2. As can be seen from Table 5, in this embodiment, compared with the stage before the ultrasonic treatment, the soluble components of the sludge 14 after the ultrasonic treatment are also increased, and the sludge is also liquefied.

314708 ptd Page 16 200306955 V. Description of the invention (11) Table 5: Properties of the returned sludge and ultrasonic treatment sludge in Example 2 Return sludge Ultrasonic treatment sludge SS (mg / L) 49800 CODCr (mg / L) 46500 — S-CODCr (mg / L) 20 2300 Organic acid (mg / L) < 10 < 10

S-CODCr: Solubility COD Table 6 shows the water quality of the treated water 5 of the biological treatment system of the biological sludge treatment system of Example 2 of the present invention. As can be seen from Table 6, in this example, a good treated water quality with an SS of 8 mg / L and a CoDc of 24 mg / L was obtained. In addition, a good water quality of 0.4 m g / L can be obtained. Table 6: Water quality of sewage and treated water in Example 2 SS (mg / L) 66 8 CODCr (mg / L) 300 28 S-CODCr (mg / L) 190 16 Total nitrogen (mg / L) ) 27 7 Total stone (mg / L) 3.5 0.4 Figure 4 shows the change in the amount of sludge in the biological treatment tank 2 during the combined biological treatment of the remaining sludge treatment in this embodiment. Under continuous operation for about 60 days, the amount of sludge in the biological treatment tank 2 is stably maintained at about 10 kg, so it can be known that the remaining sludge treatment of the present invention can be used

314708 ptd page 17 200306955 k V. Description of the invention (12) to reduce the amount of excess sludge produced. * Comparative Example In the comparative example, the apparatus shown in FIG. 5 was used to liquefy the remaining sludge discharged during the biological treatment of organic wastewater by ultrasonic waves and return it to the nitrogen removal tank 3 1 of the biological treatment tank 2 Processing. Sewage is used as organic waste water 1 and the sewage is supplied to the biological treatment tank 2 denitrification tank 31 at a flow rate of 10 m 3 / d. The activated sludge concentration in the biological treatment tank 2 is about 300 mg-SS / L. The activated sludge mixed liquid from the nitrification tank 32 of the biological treatment tank 2 is supplied to the solid-liquid separation device 4. In this comparative example, a sedimentation tank method is used as the liquid separation device 4, and the activated sludge mixed liquid 3 is separated into treated water 5 and sedimentation sludge 6. The flow rate of the settled sludge 6 discharged from the solid-liquid separation device 4 is M m V d 5 and the sludge concentration is approximately 1 0 0 0 m g—S S / L. In this comparative example, all of the settled sludge 6 discharged from the solid-liquid separation device 4 was supplied to the ultrasonic reaction tank 13 to perform ultrasonic treatment. The ultrasonic processing conditions are the same as those of the first and second embodiments. The sludge 1 4 after the ultrasonic treatment is returned to the biological treatment tank 2. Table 7 shows the properties of the sink before the ultrasonic treatment during the treatment of this comparative example; the properties of the house sludge 6 and the ultrasonic treated sludge 14. As can be seen from Table 7, in this comparative example, it was shown that the sludge was liquefied by ultrasonic treatment. Compared with Examples 1 and 2, the soluble components of the sludge were reduced.

3] 4708.ptd Page 18 200306955 V. Explanation of the invention (13) Table 7: Properties of the returned sludge and ultrasonic treated sludge in the comparative example Return sludge Ultrasonic treated sludge SS (mg / L) 52000 CODCr (mg / L) 50000 — S-CODCr (mg / L) 24 630 Kj-N 3330 — S-Kj-N 6 51.7

S-CODCr: Soluble C0D

Kj-N: Kjeldahl Nitrogen S-Kj-N: Dissolved Kjeldahl Nitrogen Table 8 shows the quality of the treated water 5 of the biological treatment system of the comparative example of the remaining sludge treatment in the comparative example. . As can be seen from Table 8, in this comparative example, compared with Examples 1 and 2, the treated water SS and COD c of the comparative example had a higher structure, and it was found that the water quality of the comparative example was poor. In addition, the SS of the treated water is also higher than that of the embodiment, and this may be as shown in Fig. 6. Because the amount of sludge in the biological treatment tank is reduced, the sludge in the biological treatment tank 2 also flows out to the treated water 5 . In addition, the treatment water 5 has a filling of 4.1 mg / L, and the stone water from S S is added, so the treatment water 5 has a higher filling than the raw water.

314708 ptd Page 19 200306955 k V. Description of the invention (14) Table 8: Water quality of sewage and treated water in the comparative example Sewage treated water-SS (mg / L) 66 76 CODCr (mg / L) 300 118 S- CODCr (mg / L) 190 29 Total nitrogen (mg / L) 27 6 Full scale (mg / L) 3.5 4.1 Figure 6 shows the biological treatment tank in the process of the combined biological treatment of the remaining sludge treatment of the comparative example 2 Changes in the amount of sludge within. In this comparative example, the outflow of sludge was extremely intense, and the operation was stopped on the 35th day. In the system of this comparative example, stable biological treatment cannot be performed. [Industrial Applicability] According to the method for treating excess sludge of the present invention, the amount of excess sludge generated during the treatment of organic wastewater by biological treatment can be significantly reduced, and the sludge can be simultaneously removed. Of phosphorus. In addition, the amount of power required to reduce the amount of excess sludge produced can be achieved with a small amount of power. That is, according to the present invention, since ultrasonic treatment for sedimentation sludge treatment is adopted, it can be achieved with a small and simple processing device in addition to a small amount of power consumption.

314708 ptd Page 20 200306955 Brief description of the drawings [Simplified illustration of the drawings] Figure 1 shows the method according to the present invention for performing ultrasonic treatment and phosphorus recovery on the remaining sludge discharged from the biological treatment process of organic wastewater. A schematic diagram of the processing flow of processing. Fig. 2 is a flow chart showing a biological treatment system for an organic wastewater used in an embodiment of the present invention and combining sludge reduction treatment and phosphorus recovery treatment according to the present invention. FIG. 3 is a graph showing changes in the amount of sludge in the biological treatment tank in Example 1. FIG. Fig. 4 is a graph showing changes in the amount of sludge in the biological treatment tank in Example 2. Fig. 5 is a flow chart showing a biological treatment system of an organic wastewater used in a comparative example and combined with sludge reduction treatment according to ultrasonic treatment. Fig. 6 is a graph showing changes in the amount of sludge in the biological treatment tank in the comparative example. In each drawing, reference symbols refer to the following constituent elements. 1 Organic wastewater 2 Biological treatment tank 3 Activated sludge mixture 4 Solid-liquid separation device 5 Processed water 6 Settled sludge 7 Reclaimed sludge 8 Recycled sludge part 9 Phosphorus release tank 10 Treated sludge 11 Sludge concentration Machine 12 concentrated sludge

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Claims (1)

200306955 6. Scope of patent application 1. A method for treating organic waste water that can recover phosphorus is used for treating the remaining sludge generated during the treatment of organic waste water consisting of a biological treatment process and a solid-liquid separation process, and its characteristics In order to concentrate a part or all of the remaining sludge to generate a dissolution liquid and concentrated sludge, and then perform a phosphorus recovery treatment on the generated dissolution liquid and return it to a biological treatment process or discharge it out of the system as treated water. At the same time, the concentrated sludge generated by the concentration of the remaining sludge is subjected to ultrasonic treatment and returned to the biological treatment process. 2. The method according to item 1 of the scope of patent application, wherein the phosphorus recovery treatment of the above-mentioned dehydration liquid is to form a phosphate agent by condensing and precipitating phosphate ions in the above-mentioned desorption liquid, thereby separating and removing phosphorus from the liquid. get on. 3. The method of claim 1 in the scope of patent application, wherein the phosphorus recovery treatment of the release liquid is performed by adding ammonium ions and magnesium to the release liquid, or by adding calcium to the release liquid and maintaining it. The pΗ value of the release liquid is 9 or more, and the phosphorus crystals are precipitated. This is performed by separating and removing phosphorus from the liquid. 4. A method for treating organic wastewater, characterized in that: biological treatment of organic wastewater is performed in a biological treatment tank, and then solid-liquid separation is performed on the activated sludge mixture liquid discharged from the biological treatment tank to generate precipitated sludge and treated water And concentrate a part or all of the remaining sludge to generate detachment liquid and concentrated sludge, and then perform phosphorus recovery treatment on the generated detachment liquid and return it to the biological treatment process or discharge it to the system as treated water In addition, at the same time for the 314708 ptd page 23 200306955 6. Scope of patent application Concentrated sludge undergoes ultrasonic treatment 'and returned to the biological treatment process. '5. The method according to item 4 of the scope of the patent application, wherein the phosphorus recovery treatment of the above-mentioned release liquid is to condense the acid ions in the release liquid by adding a coagulant, and to separate and remove the liquid from the liquid. Phosphorous way to proceed. 6. The method according to item 4 of the scope of patent application, wherein the filling and recovery treatment of the release liquid is performed by adding the ions and magnesium to the release liquid, or by adding calcium to the release liquid and maintaining it. The pH of the deliquoring solution is 9 or more, and the phosphorus crystals are precipitated. This is performed by separating and removing phosphorus from the liquid. 7. —An organic wastewater treatment device capable of recovering phosphorus is used to treat the remaining sludge generated during the organic wastewater treatment process composed of the biological treatment process and the solid-liquid separation process, which is characterized by: Sludge concentrator for concentrating part or all of the above-mentioned remaining sludge to produce detached liquid and concentrated sludge; _ scale recovery tank for phosphorus recovery treatment of detached liquid generated by sludge thickener; Ultrasonic treatment device for ultrasonic treatment of the generated concentrated sludge; and φ returns the sludge processed by the ultrasonic treatment device to the pipe of the biological treatment process. 8. The device according to item 7 of the scope of patent application, which includes a pipe for returning the processing liquid processed by the phosphorus recovery tank to the biological processing process. 9. An organic wastewater treatment device, comprising: receiving organic Page 24 3] 4708 ptd 200306955 6. Biological treatment tank for biological treatment of patent application wastewater; solid-liquid separation of the activated sludge mixed liquid discharged from the biological treatment tank to generate sediment sludge and solids of treated water Liquid separation device; a sludge concentrator that concentrates part or all of the precipitated sludge discharged from the solid-liquid separation device to generate detached liquid and concentrated sludge; performs phosphorus recovery treatment on the detached liquid generated by the sludge thickener A phosphorus recovery tank; an ultrasonic treatment device that performs ultrasonic treatment on the concentrated sludge generated by the sludge thickener; and a pipe that returns the sludge processed by the ultrasonic treatment device to the biological treatment tank. 10. The device according to item 9 of the scope of patent application, which includes a pipe for returning the processing solution processed by the phosphorus recovery tank to the biological processing tank. 314708 ptd Page 25