JP2004351250A - Method for managing operation of organic sludge fermenting/decomposing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for the operation of an organic sludge fermenting/decomposing apparatus constituted so that the flocculated and dehydrated sludge cake can be fermented/decomposed in a colony where a high-temperature aerobic microbe lives. <P>SOLUTION: The sludge cake of 80-87% moisture content is obtained by dehydrating the anionically and cationically flocculated organic sludge. The obtained sludge cake is dispersed homogeneously in the colony of ≤50% moisture content stored in a fermentation/decomposition tank 18 whose temperature is adjusted to 50-60°C. The sludge cake-dispersed colony is agitated at intervals of 2-3 hours until the colony becomes inviscid so as to ferment/decompose the sludge cake. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to the technical field of an operation management method of an organic sludge fermentation decomposition treatment device.
[0002]
[Prior art]
Today, environmental issues have been widely taken up, but the treatment of organic sludge as a household waste also poses problems, such as global warming and air pollution caused by conventional incineration, and incomplete disposal by landfill. Therefore, further improvement of the processing method has been strongly demanded.
Therefore, as a treatment facility for such organic sludge, means for quantitatively transferring raw water of organic sludge from a sludge storage tank (raw water transfer pipe), means for supplying a coagulant from a coagulant tank (coagulant supply pipe), Means for mixing and reacting raw water and a coagulant (coagulation reaction tank), dehydration means for dewatering the coagulated sludge obtained by the coagulation reaction means, and oxidizing the dewatered cake obtained by the dehydration means with a microbial medium It is provided with an organic sludge treatment means (organic sludge treatment tank) which decomposes and reduces the weight, and a deodorization means (deodorization tank) for deodorizing the odor generated by the organic sludge treatment means with a microorganism medium, and is obtained by the dehydration means. The sludge cake is put into a colony provided in the organic sludge treatment means, and the colony is stirred and mixed well with the sludge cake, whereby the sludge cake is fermented and decomposed to reduce its weight. Those manner is known (Patent Document 1).
[0003]
[Patent Document 1]
JP 2001-300586 A
[Problems to be solved by the invention]
However, although the above-mentioned conventional one is proposed up to the principle or the structure of the treatment apparatus, a suitable operation management method for fermenting and decomposing the sludge cake has not been established. In the treatment, there is a problem that an efficient and stable treatment of organic sludge cannot be performed by trial and error, and there is a problem to be solved by the present invention.
[0005]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and has been made with the object of solving these problems. The invention of claim 1 is directed to coagulating a sludge solution transferred from a sludge storage tank to a cushion tank. After coagulation and solid-liquid separation, the coagulated solid sludge is converted into a sludge cake having a water content of 80 to 87% by a dehydrator. In a fermentation cracking tank, the amount of colony is adjusted to 30 cubic meters or more per 1 ton of sludge cake, and the mixture is supplied evenly once a day to the inside of the colony. The supplied colonies are adjusted while controlling the temperature and moisture so that the temperature in the fermentation decomposition tank is at least 40 ° C., preferably 50 to 60 ° C., and the water content of the colonies is 50% or less. An organic sludge fermentation decomposition apparatus characterized in that agitation at a slow speed is performed to control the colonies so that the colonies are kept in a state of good separation fluidity and to promote fermentation decomposition of the sludge cake. This is the operation management method.
By operating as described above, sludge can be continuously and efficiently fermented and decomposed in a sludge treatment facility.
The invention of claim 2 is the operation management method of the organic sludge fermentation decomposition treatment apparatus according to claim 1, wherein the sludge cake is supplied into the colony once a day. Thus, daily management can be performed on a daily basis.
According to a third aspect of the present invention, in the first or second aspect, the sludge cake is fermented and decomposed in about 24 hours after the sludge cake is supplied to the colony to reduce the volume thereof. It is a method, and by doing so, it is possible to efficiently perform continuous sludge treatment every day.
The invention of claim 4 is the operation management method of the organic sludge fermentation decomposition treatment apparatus according to claim 1, 2 or 3, wherein the colonies are replaced and exchanged about once every six months. By doing so, the fermentation decomposition of the organic sludge can be continuously performed.
The invention according to claim 5 is the organic sludge according to claim 4, characterized in that in the start-up operation after colony exchange, the supply amount of the sludge cake is initially reduced and gradually increased to approach a fixed ratio. This is an operation management method of the fermentation decomposition treatment device, and by doing so, the start-up operation can be reliably performed.
The method according to claim 6, wherein an organic supplemental nutrient is added as appropriate to measure the propagation of the high-temperature aerobic microorganisms. Yes, this makes it possible to start up quickly.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a sludge storage tank (including a surplus sludge storage tank). Sludge liquid in the sludge storage tank 1 is transferred to a cushion tank 3 by a sludge transfer pump 2, and further coagulated by a sludge supply pump 4. It is supplied to the reaction tank 5. A flow meter 7 is provided in a sludge supply path 6 from the cushion tank 3 to the coagulation reaction tank 5, and a supply amount (flow rate) of the sludge liquid to the coagulation reaction tank 5 is measured, and a predetermined amount ( (For example, one day) is supplied to the agglutination reaction tank 5. In addition, 8 and 9 are agitators provided in the cushion tank 3 and the coagulation reaction tank 5.
[0007]
On the other hand, 10 is a water supply tank, and the cation dissolving tank 11 and the anion dissolving tank 12 which receive water from the water supply tank 10 automatically dissolve a cationic polymer flocculant and an anionic polymer flocculant, respectively. The respective dissolved coagulant aqueous solutions are supplied to the anion reaction chamber 5a and the cation reaction chamber 5b of the coagulation reaction tank 5 via the coagulant supply pumps 11a and 12a. In the flocculation reaction tank 5, the sludge in the sludge liquid supplied from the cushion tank 8 is coagulated into a sludge solid (precipitate) by the supplied flocculant, and reacted to be separated into solid and liquid.
In addition, 11b and 12b are agitators provided in the dissolution tanks 11 and 12, and 11c and 12c are automatic coagulant supply machines provided in the dissolution tanks 11 and 12.
[0008]
Reference numeral 13 denotes a dehydrator. Although the dehydrator 13 employs a screw press type dehydrator in the present embodiment, the dehydrator 13 has an agglutination reaction in the agglutination reaction tank 5 and solids. A reaction solution separated into a liquid and a solid is supplied through a concentrator 14 for concentrating the reaction solution (reaction water) by, for example, filtering the reaction solution (reaction water). The coagulation reaction liquid is separated into drainage and sludge cake by the dehydrator 13, and the sludge cake is adjusted in the dehydrator 13 so that the water content is 80 to 87%. If the water content of the sludge cake deviates from this value, the fermentation decomposition in a fermentation decomposition tank described later is hindered, and there is a fear that efficient fermentation decomposition cannot be performed.
In addition, the water stored in the water supply tank 10 is supplied to the dehydrator 13 and the concentrator 14 by the water supply pumps 13a and 14a as washing water, and the dehydrator 13 removes the washing water and the dewatered wastewater. The washing water is supplied to the filtrate separation tank 15 and the washing water is supplied to the filtrate separation tank 15 in the concentrator 14.
[0009]
The sludge cake 16 generated by the dewatering process by the dehydrator 13 is supplied to a spraying vehicle 20 provided with a stirring device 19 provided in a fermentation decomposition tank 18 via a carrier 17 constituted by, for example, a belt conveyor. You. The fermentation / decomposition tank 18 is filled with a colony 21 using a tree piece (for example, cedar chip, cedar piece) cut (or pulverized) to a size of about 2 to 15 mm in average diameter as a carrier. The amount of 21 is supplied at a rate of 30 cubic meters (m ³ ) or more per 1 ton (t) of sludge cake. When the ratio of the colony 21 to the sludge cake is smaller than this, the fermentation decomposition rate of the sludge cake in the colony decreases, and the efficiency becomes poor. Therefore, if the amount of sludge generated in one day is known, the required amount of the colony 21 is calculated backward, and a processing facility corresponding to this can be constructed. In addition, cedar chips are preferred as the tree pieces, because cedar wood has many fine pores and is suitable as a carrier that provides a suitable environment for living microorganisms. Incidentally, if the water content of the tree pieces is set to 50% or less in accordance with the water content of the colony 21 described later, there is an advantage that the water content of the colony 21 is promptly adjusted, which is convenient.
Then, the sludge cake 16 supplied to the spraying cart 20 is sprayed evenly and uniformly on the colonies 21 while being stirred. A plurality of air supply ports 22 provided in a matrix are provided on the floor surface 18a where the colonies 21 of the fermentation decomposition tank 18 are deposited, and air is supplied from the air supply ports 22 by an air supply blower 23. The air (outside air) warmed by the duct heater 24 is supplied. The air in the fermentation decomposition tank 18 is supplied to the microorganism deodorizing tank 25 through the exhaust duct 18b and is subjected to a deodorizing action. The deodorized air is exhausted to the atmosphere by the exhaust fan 25a, and The generated drain water is drained to the raw water tank 26.
In the fermentation / decomposition tank 18, gentle stirring by the slow rotation of the stirring device 19 that moves together with the spraying truck 20 is repeated, and water is appropriately adjusted by receiving water from the water supply tank 10. By supplying warm air from the air vent 22 and exhausting the air in the tank, the temperature in the tank is adjusted to at least 40 ° C. or more, preferably 50 to 60 ° C., whereby the sludge sprayed to the colony 21 is adjusted. The cake 16 is fermented and decomposed by the high-temperature aerobic microorganisms living in the colony 21 to reduce its volume. In this case, the colony 21 is kept at the above-mentioned temperature to maintain a smooth and granular state with good separation and fluidity. And the water content are controlled, and the fermentation decomposition of the supplied sludge cake 16 is adjusted to be completed in about 24 hours after the supply. .
Here, it is important to maintain the colony 21 in a smooth state having a water content of 50% or less, and if it exceeds 50%, anaerobic microorganisms may proliferate and smooth fermentation and decomposition may be inhibited. is there.
[0010]
The colony 21 is characterized in that the high-temperature aerobic microorganisms ferment and decompose the tree pieces together with the organic sludge, so that the tree pieces are gradually thinned and the propagation environment of the microorganisms is reduced. The breeding environment may be improved by adding new pieces of wood, but after a suitable period of time, it is preferable to replace and replace.The frequency of replacement and replacement in this case is, for example, about once every six months, once a year, etc. Periodically, it is preferable for management, and the start-up operation after colony exchange is to gradually increase the amount of sludge cake supplied so as to be adjusted to the predetermined ratio. In order to promote the propagation of aerobic microorganisms and to promote fermentation, it is also necessary to mix and supply organic nutrients such as fish meal and food waste oil to sludge cakes as auxiliary fermenting agents to the colonies.
In addition, the temperature and humidity environment in the fermentation / decomposition tank 18 at the time of start-up is to control the water content of the colonies to be high and to increase the temperature in order to promote the growth of high-temperature aerobic microorganisms. It is preferable to manage.
[0011]
In the embodiment of the present invention configured as described above, when the final sludge generated in the terminal sludge treatment plant is decomposed by the organic sludge fermentation decomposition treatment apparatus, when the operation is performed by the operation management method, the efficiency of the organic sludge is reduced. Good fermentation decomposition can be performed continuously and stably.
[0012]
By operating the fermentation decomposition of the amount of sludge generated in one day in one day, daily sludge treatment can be managed continuously on a daily basis, which is convenient. The sludge cake may be supplied to the colony 21 as long as a predetermined amount (regular or irregular) is supplied in accordance with the fermentation decomposition ability of the colony 21. The sludge cake for the day may be supplied to the colony 21 in a plurality of times, or the sludge cake for a plurality of days may be supplied.
In addition, the colony 21 needs air supply for fermentation and curing for fermentation, and it is preferable to stir the colony 21 slowly, in which case, it is necessary to continuously stir. However, if necessary, intermittent stirring can be employed, and by adjusting the stirring in this manner, fermentation decomposition can be promoted more efficiently.
[0013]
Incidentally, as the stirring device 19, a device as shown in FIG. 2 can be employed. This stirrer 19 is of a self-propelled type (self-propelled mechanism is omitted) in order to stir in the longitudinal direction. On the other hand, the stirring is performed in the left-right width direction by rotation of four horizontal stirring shafts 26 having a plurality of fin-shaped blades 26a, and the colonies 21 in the fermentation decomposition tank 18 are spread over the entire tank. Although stirring can be performed efficiently, the stirring speed in this case is preferably slow enough that the colonies 21 are not scattered. The upper and lower horizontal stirring shafts 26 are preferably rotated in directions opposite to each other as shown in FIG. 4 so as to be sent backward with respect to the moving direction, whereby the stirring efficiency of the colony 21 is improved. . The lower side of the horizontal stirring shaft 26 has a larger number of blades, so that the stirring efficiency is increased.
In addition, when the colony 21 is reduced in weight or when the fermentation decomposition ability is reduced, it is required to consider adding a tree piece to increase the decomposition ability.
Furthermore, it has been confirmed that the collected used colonies contain a large amount of organic fermentation degradation products and can be effectively used as organic fertilizers and soil conditioners.
[Brief description of the drawings]
FIG. 1 is a flowchart of an organic sludge fermentation decomposition treatment apparatus.
FIG. 2 is a flow chart of an organic sludge fermentation decomposition treatment system.
FIG. 3 is a front view of the stirring device.
FIG. 4 is a schematic diagram showing a rotation direction and a movement direction of a horizontal stirring rod.
[Explanation of symbols]
Reference Signs List 1 sludge storage tank 3 cushion tank 5 coagulation reaction tank 13 dehydrator 16 sludge cake 18 fermentation decomposition tank 19 stirrer 21 colony

Claims (6)

After the sludge liquid transferred from the sludge storage tank to the cushion tank is coagulated in the coagulation reaction tank and solid-liquid separated, the coagulated solid sludge is converted into a sludge cake having a water content of 80 to 87% by a dehydrator. In a fermentation / decomposition tank in which a colony inhabiting a high-temperature aerobic microorganism using a tree piece as a carrier, the amount of the colony is adjusted to 30 cubic meters or more per 1 ton of sludge cake, and the inside of the colony is adjusted at a predetermined timing. Supply to
Thereafter, the colonies to which the sludge cake has been supplied are subjected to temperature and moisture adjustment so that the temperature in the fermentation decomposition tank is at least 40 ° C., preferably 50 to 60 ° C., and the water content of the colonies is 50% or less. The organic sludge fermentation / decomposition treatment characterized by performing stirring at a slow speed to control the colonies to maintain a state of good separation and fluidity and to promote fermentation / decomposition of the sludge cake. Device operation management method. The method according to claim 1, wherein the sludge cake is supplied into the colony once a day. 3. The method according to claim 1, wherein the sludge cake is fermented and decomposed in about 24 hours after supply to the colony to reduce its volume. 4. The operation management method for an organic sludge fermentation decomposition treatment apparatus according to claim 1, wherein the colonies are replaced and exchanged about once every six months. 5. The operation control of the organic sludge fermentation decomposition treatment apparatus according to claim 4, wherein in the start-up operation after the colony exchange, the supply amount of the sludge cake is initially reduced and gradually increased to approach a fixed ratio. Method. The operation management method for an organic sludge fermentation decomposition treatment apparatus according to claim 4 or 5, wherein an organic supplemental nutrient is appropriately added to measure the propagation of the high-temperature aerobic microorganisms.

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