JPH06154796A - Method and equipment for sludge treatment - Google Patents

Abstract

PURPOSE:To solve the problem that decomposition of sludge progresses during transportation through a pipeline and offensive odor is generated by supplying ozone into a sludge treatment tank, bringing ozone into contact with sludge, reacting ozone with sludge to treat sludge and thereafter transporting sludge through a sludge feed pipe. CONSTITUTION:Sewage sludge is introduced into a contact reaction tank 3 through a sludge feed pipe 2 by a sludge feed pump 1. Ozone is supplied to the contact reaction tank 3 through an air diffuser 6 by operating a circulation blower 5 of discharged ozone and brought into contact with sewage sludge. At this time, an agitation motor 7 is driven and sludge is stirred to promote contact with ozone. Offensive odor is removed and also anaerobic bacteria are sterilized by bringing ozone into contact with sludge in such a way. Furthermore decomposition of sludge is controlled by increasing dissolved oxygen. Sedimentation properties (concentration properties) of transported sludge are enhanced. Thereafter sludge treated by ozone is transported to a treatment tower 9 of discharged ozone through a sludge feed pipe 8 by a sludge feed pump 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to sludge treatment, and more particularly to sludge treatment that suppresses anaerobic recent activity in sludge in a sludge pipe to suppress sludge decay.

[0002]

2. Description of the Related Art Conventionally, sludge treatment has been required in various fields. For example, in a sewage treatment plant, the generated sludge amount is about 1% of the sewage treatment amount, and this sludge treatment is often performed independently for each sewage treatment plant.

Generally, in a metropolitan area, a plurality of sewage treatment plants are often close to each other due to factors such as population concentration, and sludge generated from each of these sewage treatment plants is concentrated in one place. By performing the treatment, the sludge treatment time can be shortened and the sludge treatment cost can be reduced.

[0004] In order to carry out the integrated treatment of sludge, it is necessary to transport the sludge generated in each treatment plant to the central sludge treatment plant,
The transportation methods include truck transportation, ship transportation, and pipe transportation.

The above-mentioned sewage sludge to be transported is a mixture of surplus sludge of water treatment system, digestion and desorption liquid, etc. Especially, when the sewage sludge is transported by a pipe, the sewage sludge is transported during the transportation. There is a risk of decay and deterioration.

The sewage sludge to be transported is a mixture of excess sludge in the water treatment system, nitrifying and desorbing liquid, and the like.

[0007] Further, it often takes about 5 to 24 hours until the sewage sludge is transported and processed. The water content of this sludge is 99% (sludge 1%, water 99%)
It is a degree.

[0008]

However, when sludge is intensively processed by pipe transportation or the like, the inside of the transportation pipe (mud feeding pipe) is in an absolutely anaerobic state, and the deterioration of sewage sludge progresses due to the propagation of anaerobic microorganisms. Will be faster. In addition, deposits in the transportation pipes also contribute to the deterioration and alteration of sewage sludge.

When the sewage sludge is deteriorated or deteriorated in this way, the sludge settling property and dewatering property are deteriorated when the sludge is treated in the central sludge treatment plant, and the sludge treatment after the sludge aggregation is stably performed. Will be difficult. Therefore, for example, the dehydration filtration rate is reduced by about 30%, and it is necessary to increase the consumption amount of dehydration chemicals and the number of dehydrators.

Further, as the sludge decays as described above,
In sludge treatment processes such as concentration and dehydration, the amount of offensive odors increases and the working environment deteriorates, and it is also necessary to increase the number of deodorizers installed.

The present invention has been made based on the above background, and an object thereof is to prevent spoilage and deterioration during transportation of sludge, and to contribute to improvement of treatment efficiency in sludge treatment and reduction of cost.

[0012]

Means and Actions for Solving the Problems In order to solve the above problems, the present invention supplies ozone into a sludge treatment tank, treats sludge with ozone to cause a sludge treatment, and then treats the sludge. Provided is a sludge treatment method for transportation to a mud pipe.

Also provided is a sludge treatment device having a sludge treatment tank, an ozone supply means for supplying ozone to the sludge in the sludge treatment tank, and a sludge transportation means for transporting the ozone-treated sludge to a sludge transportation pipe. To be done.

Further, in the sludge treatment device, there is also provided a sludge treatment device having an exhaust ozone circulation supply means for collecting and re-supplying the exhaust ozone generated in the treatment tank.

Usually, ozone is supplied by a method of diffusing ozone gas, flowing in a solution of ozone, or the like. In the present invention, the supplying method and means are not particularly limited, and the gas phase, The supply can be performed in any state such as a solid phase, a liquid phase, or a combination thereof.

The sludge transportation means may be a pump or the like, but the transportation means is not particularly limited. A blower or the like can be used as the exhaust ozone circulation supply means, but the exhaust ozone circulation supply means is not particularly limited.

By collecting the exhaust ozone by the exhaust ozone circulation supply means and supplying it again, the ozone treatment can be efficiently performed. Therefore, both the amount of ozone used and the amount of exhausted ozone are reduced, which is economically advantageous.

By contacting ozone with sludge as described above, anaerobic bacteria and the like are sterilized, and a bad odor removing action is also obtained. Further, since the dissolved oxygen also increases, the progress of sludge decay can be suppressed. Therefore, decay of sludge during transportation of sludge is suppressed.

Further, since the sludge condensability is also improved, the sludge settling treatment can be carried out quickly after transportation.

[0020]

EXAMPLE In this example, ozone and ozone water were supplied to the sludge by using the sludge treatment device shown in FIG. 1, and the sludge was brought into contact with ozone to suppress spoilage and deterioration.

In FIG. 1, reference numeral 1 denotes a sludge pump for supplying sludge to the contact reaction tank 3 through the sludge pipe 2, and reference numeral 4 denotes a sludge pump for feeding the ozone-treated sludge to the sludge pipe 8.

Reference numeral 5 is an exhaust ozone circulating blower for circulating exhaust ozone and re-supplying it to the contact reaction tank 3 through the air diffuser 6, 7
Is a stirring motor that stirs the sludge in the contact reaction tank 3 to promote the contact reaction between ozone and sludge, and 9 is an exhaust ozone treatment tower that processes the exhaust ozone.

The sludge treated with ozone by the above apparatus is transported to a sludge treatment center or the like through the sludge pipe 8.

A mud receiving tank may be used instead of the contact reaction tank 3.

When the sludge and ozone are brought into contact with each other by the above-mentioned apparatus to carry out the transportation, the anaerobic bacteria in the sludge are sterilized to prevent the sludge from spoiling and deteriorating during the transportation, and the odor is removed. Also got.

Further, since ozone and ozone water are uniformly and slowly stirred by the stirring motor 7 and the circulation bag is provided by the exhaust ozone circulation blower, the ozone treatment effect is increased.

Further, since the sludge flocculation property is also improved, the amount of the flocculation-precipitating agent for dehydration introduced into the chemical is reduced, and the dehydration filtration rate is also shortened.

[0028]

INDUSTRIAL APPLICABILITY In the present invention, the bad odor is removed by the contact reaction effect of ozone (ozone gas, ozone water, etc.) and sludge. In addition, anaerobic bacteria are sterilized and dissolved oxygen increases, so that spoilage can be suppressed. Therefore, the sedimentation property (concentration property) of the transported sludge is also improved.

Further, since the sludge condensability is improved, the amount of chemicals such as a coagulant for dewatering can be reduced, and the dewatering filtration rate can be shortened. Further, the odor contained before the ozone treatment can be removed by the ozone treatment.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a sludge treatment device according to an embodiment of the present invention.

[Explanation of symbols]

Reference numeral 1 denotes a sludge pump for supplying sludge to the contact reaction tank 3 through the sludge pipe 2, and 4 denotes a sludge pump for feeding the ozone-treated sludge to the sludge pipe 8. Reference numeral 5 is an exhaust ozone circulation blower that circulates the exhaust ozone and re-supplies it to the contact reaction tank 3 through the air diffuser 6, and 7 is a stirring motor that agitates the sludge in the contact reaction tank 3 to accelerate the contact reaction between ozone and sludge. , 9 is a blower which is a waste ozone treatment tower for treating waste ozone 2 ... Ozone generator 3 ... Ozone-containing water production device 4 ... Ozone decomposition device 5 ... Injection pump 7 ... Sludge pressure feed pipe

Claims (3)

[Claims] 1. A sludge treatment method in which ozone is supplied into a sludge treatment tank, sludge and ozone are brought into contact with each other to treat sludge, and then the sludge is transported to a sludge pipe. 2. A sludge treatment device having a sludge treatment tank, an ozone supply means for supplying ozone to the sludge in the sludge treatment tank, and a sludge transportation means for transporting the ozone-treated sludge to a sludge transportation pipe. 3. The sludge treatment device according to claim 2, further comprising an exhaust ozone circulation supply unit that recovers and resupposes exhaust ozone generated in the treatment tank.