JP4575270B2 - Excess sludge reduction equipment - Google Patents

Description

  The present invention relates to a facility for reducing excess sludge that can efficiently reduce excess sludge generated when wastewater and industrial wastewater are treated with wastewater treatment equipment, and can discharge more purified treated water. It is.

  Domestic wastewater and industrial wastewater are usually treated by a standard activated sludge method or a membrane-separated activated sludge method. At this time, surplus sludge mainly composed of sludge microorganisms is generated. In recent years, the final disposal site for surplus sludge has decreased, and the disposal cost has soared, which has become a heavy burden on companies.

  Until now, various devices for reducing the excess sludge have been created and used, but further improvements are desired in terms of reduction efficiency. In addition, conventionally, since facilities such as a dehydrator, a dryer, and an incinerator for treating excess sludge are required, it is also desired that such facilities be unnecessary. Moreover, it is also desired that the treated water after reducing the excess sludge is further purified and discharged.

  The present invention was devised in view of these problems, and it is an object of the present invention to provide a surplus sludge reduction facility that can reduce excess sludge more efficiently and discharge more purified treated water. .

  This will be described with reference to FIGS. The surplus sludge reduction facility 1 according to claim 1 is a facility for continuously processing surplus sludge S generated when domestic wastewater or industrial wastewater is treated with a wastewater treatment facility, and at least the surplus sludge S is removed. The sludge storage tank 10 provided with a feed pump 12 that is temporarily stored and operated by the air diffuser 11 and the timer 13 and the excess sludge S in the sludge storage tank 10 are automatically fed by the feed pump 12. The digestion / decomposition apparatus 20 is provided with an ultrafine bubble device 23 in which the filtration membrane group 22 and a part of the rising bubbles are in contact with the filtration membrane group. The ozone generator 30 that supplies ozone to the digestion / decomposition tank 21 together with the air supplied from the blower 32 and the treated water W that has passed through the filter membrane group 22 are temporarily passed through the sterilization treatment device 41 provided inside. Storage After, the treated water storage tank 40 to discharge, a discharge ozone that has not dissolved in the digestive decomposition bath 21, a discharging ozone removal device 50 to release by treatment below the specified concentration, it is made comprises a.

  The surplus sludge reduction facility 1 according to claim 2 is a facility for continuously treating surplus sludge S generated when domestic wastewater or industrial wastewater is treated with a wastewater treatment facility, and at least the surplus sludge S is removed. The sludge storage tank 10 provided with a feed pump 12 that is temporarily stored and operated by the air diffuser 11 and the timer 13 and the excess sludge S in the sludge storage tank 10 are automatically fed by the feed pump 12. The digestion / decomposition apparatus 20 is provided with an ultrafine bubble device 23 in which a filtration membrane group 22 and a part of the rising bubbles are in contact with the filtration membrane group. The ozone generator 30 that supplies ozone to the digestion / decomposition tank 21 together with the air supplied from the blower 32, and the treated water W that has passed through the filtration membrane group 22 are temporarily passed through the sterilization treatment device 41 provided inside. Storage Thereafter, the treated water storage tank 40 to be discharged, the exhausted ozone removal apparatus 50 that processes and discharges the exhausted ozone not dissolved in the digestion / decomposition tank 21 to a specified concentration or less, and the filtration membrane group 22 when the filtration is performed. And a membrane cleaning pipe 60 for supplying hypochlorine for powerful cleaning to the group.

  A surplus sludge reduction facility 1 according to claim 3 is the invention according to claims 1 and 2, wherein the filtration membrane group 22 is arranged in a Zenon membrane, an immersion flat membrane, an element type ceramic membrane, and an immersion type ceramic membrane. It is comprised by the film | membrane containing at least any one of these.

  The surplus sludge reduction facility 1 according to claim 1 can efficiently reduce the surplus sludge S by the action of ozone and the like, and further treat the treated water W by the action of the filtration membrane group 22 and the like. It can be cleaned and released.

  That is, since the ozone generated by the ozone generator 30 is supplied to the digestion / decomposition tank 21 to which the excess sludge S is supplied, the excess sludge S is oxidized to come into an organic substance that is easily biodegraded by contact with the ozone. Furthermore, by continuing the contact, it is decomposed into carbon dioxide gas and water (treated water W). Therefore, the excess sludge S is efficiently reduced.

  Moreover, since the treated water W is filtered through the filtration membrane group and then sterilized by the sterilization treatment apparatus and discharged, the purified treated water W can be discharged.

  In the sludge storage tank 10, air is supplied by the air diffuser 11 and the surplus sludge S is aerated, so that sludge microorganisms constituting the surplus sludge S are activated and efficient reduction in the digestion / decomposition tank 21 is achieved. Contribute to. Moreover, since the surplus sludge S is continuously (periodically) supplied to the digestion / decomposition tank 21 by the infeed pump 12 that is operated by the timer 13 provided in the sludge storage tank 10, the amount of surplus sludge S can be reduced efficiently. It can be carried out.

  In addition, since the exhaust ozone which did not melt | dissolve in the digestive decomposition tank 21 is processed and discharged | emitted by the exhaust ozone removal apparatus 50 by the regular density | concentration, for example, 0.1 ppm or less, problems, such as environmental pollution, do not generate | occur | produce.

  In addition, according to the present invention, the amount of excess sludge S can be reduced, and eventually all of it can be eliminated. Therefore, facilities such as dehydrators, dryers, incinerators, etc., which have been conventionally required for treating excess sludge S. Can be made unnecessary. Further, since the amount is reduced by ozone, the bad odor emitted by the high concentration excess sludge S can be eliminated.

  The surplus sludge reduction facility 1 according to claim 2 can efficiently reduce surplus sludge S and further purify the treated water W thereafter, as in the invention according to claim 1. Can be released.

  Moreover, since this equipment is provided with a membrane cleaning pipe 60 for supplying hypochlorite for strong cleaning to the filtration membrane group 22, it is not cleaned by the ultrafineness of the ozone-containing air rising from the ultrafine bubble device. Thus, the filtration membrane group 22 that is blocked can be reliably washed. Since this hypochlorous acid has the ability to dissolve and sterilize the cell nucleus of sludge microorganisms, all the sludge microorganisms that cause clogging of the filtration membrane group 22 can be removed.

  The surplus sludge reduction facility 1 according to claim 3, similarly to the inventions according to claims 1 and 2, efficiently reduces the surplus sludge S and discharges the treated water W in a purified state thereafter. be able to.

  Further, the filtration membrane group 22 is composed of at least one of the four membranes of Zenon membrane, submerged flat membrane, element type ceramic membrane, and submerged ceramic membrane. The treated water W can be discharged.

  Embodiments of the excess sludge reduction facility 1 according to the present invention are shown in FIGS. 1 and 2. This is a facility that continuously treats high-concentration surplus sludge S that is generated when domestic wastewater and industrial wastewater are treated with a wastewater treatment facility. The sludge storage tank 10, the digestion / decomposition device 20, the ozone generator 30, A treated water storage tank 40, a waste ozone removing device 50, and a membrane cleaning pipe 60 are provided.

  The sludge storage tank 10 temporarily stores surplus sludge S that has been transported as input Y, and includes an aeration device 11 and a feed pump 12 that is operated by a timer 13 inside. Air is supplied from the blower 14 to the air diffuser 11.

  In the digestion / decomposition apparatus 20, the excess sludge S in the sludge storage tank 10 is automatically (periodically) supplied by the feed pump 12 that is operated by the timer 13. Further, the digestion / decomposition tank 21 inside thereof is provided with a filtration membrane group 22 and an ultrafine bubble device 23 in which a part of the rising bubbles contacts the filtration membrane group 22. The filtration membrane group 22 is composed of at least one of three types of filtration membranes: a Zenon membrane, an immersion flat membrane, an element ceramic membrane, and an immersion ceramic membrane that pass in series.

  The ozone generator 30 generates high-concentration ozone and supplies it to the digestion / decomposition tank 21. This ozone is mixed with the air supplied from the blower 32 and supplied to the ultrafine bubble device 23 through the mixing tube 31, where it is converted into ultrafine bubbles and supplied to the lower part of the digestion / decomposition tank 21, and surplus sludge. Effective contact with S.

  The treated water storage tank 40 passes through the filtration membrane group 22 and sterilizes the purified treated water W having a BOD of 5 mg / liter or less by the sterilization treatment device 41 provided therein, and then temporarily stores the treated water W, The treated water W is discharged.

  The exhaust ozone removal device 50 treats and releases exhaust ozone (2000 to 3000 ppm) that has not been dissolved in the digestion / decomposition tank 21 to a specified value that is a concentration defined by the occupational health standards, that is, 0.1 ppm or less. The membrane cleaning tube 60 supplies hypochlorous acid to the filtration membrane group 22 when the filtration membrane group 22 is closed to wash the filtration membrane group 22.

  The effect | action of the excess sludge reduction | decrease equipment 1 which concerns on this embodiment is demonstrated. First, surplus sludge S stored in the sludge storage tank 10 is supplied to the digestion / decomposition tank 21 of the digestion / decomposition apparatus 20 by the feed pump 12 that is periodically operated by the timer 13. In the sludge storage tank 10, air is sent from the blower 14 to the air diffuser 11, and the air is diffused and brought into contact with the excess sludge S to activate the air.

  Next, the ozone generated by the ozone generator 30 and the air from the blower 32 are mixed in the mixing tube 31 and then supplied to the ultrafine bubble device 23 provided in the digestion / decomposition tank 21 where the ultrafine bubbles are supplied. Is generated and diffused into the digestion / decomposition tank 21 to contact the excess sludge S. Thereby, surplus sludge S changes to organic matter in contact with ozone, and further decomposes into carbon dioxide gas and water (treated water W) by coming into contact with ozone for a long time. Therefore, the excess sludge S is efficiently reduced. Note that air from the blower 32 is supplied through an air transfer pipe 33, and the air transfer pipe 33 is provided with an air escape pipe 34 for discharging excess air.

  Thereafter, the treated water W is filtered by the filtration membrane group 22, sterilized by the sterilization treatment device 41, temporarily stored in the treated water storage tank 40, and then discharged. Since this treated water W is filtered by the filtration group and further sterilized by the sterilizing apparatus 41, it is clean. The treated water W passes through the filtration membrane group 22 by the water head pressure H in the digestion / decomposition tank 21 and is sent to the sterilization treatment apparatus 41.

  The ozone (exhaust ozone) remaining in the digestion / decomposition tank 21 reaches the exhaust ozone removal device 50 through the exhaust ozone transfer pipe 51, where it is processed to a concentration of 0.1 ppm or less and discharged. This discharge is performed by the pressure feeding fan 52, the damper 53, and the exhaust ozone discharge pipe. The exhaust ozone removal device 50 is provided with a high concentration ozone decomposition catalyst material 55.

  In the present embodiment, a membrane cleaning pipe 60 for supplying hypochlorous acid is provided to purify the filtration membrane group when the filtration membrane group 22 is closed. The membrane cleaning pipe 60 communicates with the treated water pipe 42 for supplying the treated water W to the sterilization treatment apparatus 41. The treated water pipe 42 is provided with an electromagnetic valve 43 that is periodically operated by the timer 13, and the treated water W is allowed to flow for 8 minutes by opening and closing the electromagnetic valve 43 and then stopped for 2 minutes. The filtration membrane group 22 is washed by the rising bubbles supplied from. Nevertheless, when the filtration membrane group 22 is blocked, the electromagnetic valve 43 is closed, and hypochlorous acid is supplied from the membrane washing tube 60 to wash the filtration membrane group 22.

  The surplus sludge reduction facility 1 having such a configuration can efficiently reduce the excess sludge S by the action of ozone or the like. Further, the treated water W can be further purified and discharged by the action of the filtration membrane group 22 and the like.

  In the present embodiment, a reverse feed pipe 25 is provided between the digestion / decomposition device 20 and the sludge storage tank 10, and the excess sludge S overflowed in the digestion / decomposition tank 21 is returned to the sludge storage tank 10. Further, an inspection port provided with an inspection cap 24 is formed in the digestion / decomposition apparatus 20 so that the concentration of excess sludge S is measured.

  As shown in FIG. 3, the treated water discharged by the head pressure H in the digestion / decomposition tank 21 is further pressurized and discharged by the delivery pump 44, and the delivery pump 44 and the delivery pump 12 are discharged by the timer 13. And may be operated alternately. 61 and 62 are on-off valves and on-off valves, which are arranged upstream of the delivery pump 44 in the treated water pipe 42 and in the membrane cleaning pipe 60, respectively.

It is a partial section side view lineblock diagram showing an embodiment of surplus sludge reduction equipment concerning the present invention. It is a partial cross section plane block diagram of the excess sludge reduction | decrease installation shown in FIG. FIG. 3 is a partially modified view of FIG. 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surplus sludge reduction | decrease equipment 10 Sludge storage tank 11 Aeration apparatus 12 Inflow pump 13 Timer 14 Blower 20 Digestion decomposition apparatus 21 Digestion decomposition tank 22 Filtration membrane group 23 Ultrafine bubble apparatus 24 Inspection cap 25 Reverse feed pipe 30 Ozone generator 31 Mixing pipe 32 Blower 33 Air transfer pipe 34 Air escape pipe 40 Treated water storage tank 41 Sterilization treatment device 42 Treated water pipe 43 Solenoid valve 44 Delivery pump 50 Waste ozone removal device 51 Waste ozone transfer pipe 52 Pumping fan 53 Damper 54 Waste ozone discharge Pipe 55 High-concentration ozone decomposition catalyst material 60 Membrane cleaning pipe 61 On-off valve 62 On-off valve H Water head pressure S Excess sludge V Valve W Treated water Y Input

Claims (3)

  A facility for continuously treating surplus sludge (S) generated when wastewater and industrial wastewater are treated with wastewater treatment equipment, and at least temporarily store surplus sludge, and a diffuser ( 11) and a sludge storage tank (10) provided with a feed pump (12) operated by a timer (13), and excess sludge in the sludge storage tank is automatically supplied by the feed pump and digested inside A digestion / decomposition apparatus (20) provided with an ultrafine bubble device (23) in which a filtration membrane group (22) and a part of the rising bubbles are in contact with the filtration membrane group in the decomposition tank (21); An ozone generator (30) that supplies ozone to the digestion / decomposition tank together with the air supplied from the blower (32), and a sterilization treatment device (41) provided internally with treated water (W) that has passed through the filtration membrane group. ) To temporarily store and then release Treated water storage tank (40), the digested decomposition exhaust ozone undissolved in tanks, normal concentration processes below discharge ozone removing device to be released (50), excess sludge volume reduction facility consisting comprise. A facility for continuously treating surplus sludge (S) generated when wastewater and industrial wastewater are treated with wastewater treatment equipment, and at least temporarily store surplus sludge, and a diffuser ( 11) and a sludge storage tank (10) provided with a feed pump (12) operated by a timer (13), and excess sludge in the sludge storage tank is automatically supplied by the feed pump and digested inside A digestion / decomposition apparatus (20) provided with an ultrafine bubble device (23) in which a filtration membrane group (22) and a part of the rising bubbles are in contact with the filtration membrane group in the decomposition tank (21), An ozone generator (30) for supplying ozone to the digestion / decomposition tank together with the air supplied from the blower (32), and a sterilization treatment apparatus (41) provided internally with treated water (W) that has passed through the filtration membrane group. ) Through temporary storage and then release A treated water storage tank (40), a waste ozone removal apparatus (50) that discharges exhaust ozone that has not been dissolved in the digestion / decomposition tank to a specified concentration or less, and the filtration membrane when the filtration membrane group is closed A membrane cleaning pipe ( 60 ) for supplying hypochlorine for powerful cleaning to the group, and an excess sludge reduction facility. The surplus according to claim 1 or 2, wherein the filtration membrane group ( 22 ) is constituted by a membrane containing at least one of a Zenon membrane, a submerged flat membrane, an element type ceramic membrane, and a submerged ceramic membrane. Sludge reduction equipment

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