KR100945234B1 - Method of treating sludge for recycled soil - Google Patents

Abstract

PURPOSE: A method for treating sludge for recycled soil is provided to process the bulk sludge, to shorten a processing time, to increase a moisture elimination rate, and to control a percentage of water content of the processed soil through a hybrid processing without a special apparatus. CONSTITUTION: A method for treating sludge for recycled soil comprises: a mixing step(200) forming a mixture by mixing the sludge and a processing material; and a curing step(600) which injecting the mixture in a curing device and drying the mixture through hot air. The curing step includes a first curing step(600a) and a second curing step(600b) which are connected in series. The first curing step comprises: an injecting step(610) of injecting the mixture of the processing material and sludge; a drying step(630) of the dropped mixture; and a discharging step(640) of the dried mixture. The second curing step comprises: a hybrid drying step(650) desiccating the mixture dropped in the inner part of the vessel-type main body; and the discharging step(670) which discharges the mixture accumulated within the vessel-type main body to the outside.

Description

Method of treating sludge for recycled soil}

The present invention relates to a cover treatment method for treating a waste called sludge or sludge generated in a sewage treatment plant and the like to be used as a useful resource such as landfill cover material or building materials.

Sludge refers to a mud-like substance that is sedimented and separated in the process of treating sewage and wastewater. The sludge has high water content and high organic content, which is easy to rot and difficult to treat. In the past, most of these sludges were buried underground or treated with ocean dumping, and some treatment methods such as incineration, drying, composting, and solidification have been attempted.

In particular, since sewage sludge has been banned from landfills since July 2003, about 5,120 tons, or 77.1% of the 6,645 tons generated per day at the end of 2004, have been dumped at sea.

Sludge offshore dumping is being banned internationally in accordance with the London Treaty (1972), and in order to prevent future sludge offshore dumping, various efficient treatment measures are being taken.

However, incineration of sewage sludge is difficult to install incineration facilities due to high environmental investment, such as high initial capital investment costs and secondary pollutants generated during treatment. In addition, some composting has been attempted, but it is difficult to secure the use of the produced compost, so there is a limit to composting a large amount of sludge.

On the other hand, the Waste Management Act Enforcement Rule suggests that the landfill site criterion should be applied daily by compacting the soil to less than 10 centimeters by using soil that has low permeability, solidified materials or construction waste recycled after completion of the landfill operation. It is. Low water permeability according to the requirements of landfill material on landfill site, water content should be less than elution standard, water content should be 45% or less based on earth and soil so as not to stick to equipment, compressive strength should be more than 0.5kgf / ㎠, odors such as ammonia Requirement such as not to be presented.

However, in the conventional sewage sludge solidification treatment technology, an alkali-based solidifying agent such as quicklime, cement, and fly ash is mixed and cured into sewage sludge. The bad odor problem was serious, and such composition did not facilitate curing, so the compressive strength, permeability coefficient, etc. could not meet the requirements for covering or filling soil according to related laws.

Recently, processes are developed to cover sewage sludge by using a basic material and an acidic material together as a solidifying agent and using cement or quicklime as a binder for curing.

However, these theoretical process methods work well at small and laboratory levels, but often do not yield satisfactory results on high volume processing equipment. For example, if you apply a laboratory method at a large facility level that has tens of tonnes of treatment at a time and hundreds to thousands of tonnes of treatment a day, then the treatments that have the same particle size and water content as soils will be Occasionally there is a very small particle size and water content that cannot be used as cover.

For example, in the conventional sludge treatment apparatus for covering the soil, the sludge was first put in the mixer, the treatment material was added thereto, and then mixed with the internal stirrer. As a treatment apparatus through chemical agitation, stirring the base material to be treated first, and then treating the chemical after stirring is accepted as common sense in the conventional treatment apparatus, and has been continuously followed until now.

However, in the case of the existing sludge treatment apparatus which has introduced sludge as a standard operation process for a long time since the installation, the mixture obtained in the mixing step is not sufficiently mixed, and the granules are not distinct in the mixture. Achieving state has been recognized as a vague limitation of mass processing.

In addition, the mixture of the sludge and the treatment material after the mixing step is introduced into the curing machine through the transfer means, in which the hot air drying is performed in a state in which a certain amount of the mixture is added together in a batch treatment method, and after a predetermined time, the mixture is treated with hot air. The process is carried out in which the mixture is discharged all at once.

However, according to this type of curing, in a state in which the mixture is filled with mud dough with no apparent particulate formation, hot air is discharged in contact with a small area of the mixture only by a certain path, and in the state where the sludge itself is like mud dough. Due to the nature of containing water, the efficiency of draining out the contained water was not high.

Therefore, even if much more energy is input than the energy required to theoretically lower the water content in the treatment and cover of the sludge, the water content in the sludge could not be sufficiently lowered. There is a demand for an efficient sludge cover treatment apparatus capable of treating a large amount of sludge at a low cost, and a treatment method capable of having an optimum effect by such an apparatus.

The present invention is to eliminate the problems in the conventional sludge cover treatment method described above, it is possible to cover the waste through a large amount of sludge treatment, and also to reduce the processing time compared to the conventional method on the basis of the same capacity It is an object of the present invention to provide a sludge cover treatment method capable of increasing the water removal rate in sludge.

The sludge cover treatment method of the present invention for achieving the above object,

In the curing step, the mixture of sludge and the treatment material is dropped into the container-type body through the upper opening, and the mixture is dropped into the container-type body by continuing to supply hot air while preventing the discharge of the dropped mixture for a certain period of time. And a hybrid drying process for drying the dropped and loaded mixture and a discharge process for discharging the mixture loaded in the container-type body to the outside.

In the present invention, the hybrid drying process may be separately provided with a load drying process for drying only the mixture loaded with hot air without dropping the mixture.

In the hybrid drying process of the present invention, a dispersion process may be performed together to disperse the injected mixture through a dispersion apparatus so as to fall in the container-type body in a dispersed state.

In the present invention, the mixture may be made in such a manner that the treatment material is first introduced into the mixer vessel upper opening in the mixing step before the curing step and then the sludge is added and then stirred through the stirring apparatus in the mixer vessel.

On the other hand, the curing step in the present invention may be made by connecting the first curing step and the second curing step in a series (series), wherein the first curing step, the mixture of the sludge and the treatment material mixed in the mixing step Input process to drop into the container-type main body through the unit, the drying process of drying the mixture falling through the hot air discharged from the inside of the container-type body, immediately discharge the mixture dropped on the bottom of the container-type body out of the curing machine The discharge process is carried out together (the concept encompasses that these processes can be connected in series or simultaneously), and the second curing step is a hybrid drying process that characterizes the present invention. It may be provided.

According to the present invention, a large amount of sludge can be treated in a short time to cover the soil, and in addition, the treatment time can be shortened compared to the existing method, and the water removal rate in the sludge can be increased to increase the efficiency of the sludge cover.

In addition, in the operation of the sludge cover treatment device is completed, it is possible to adjust the moisture content of the treated cover through the hybrid treatment process without additional equipment, it is possible to improve the utilization rate of the equipment.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 is a simplified block diagram illustrating one embodiment of an apparatus for sludge cover suitable for the method of the present invention, and FIG. 2 is a cross-sectional view schematically showing one embodiment of a curing machine as used in the apparatus of FIG. 3 is a cross-sectional view showing a hybrid drying step performed according to the method of the present invention in a curing machine, and FIGS. 4 to 6 are flowcharts showing the steps of three different embodiments of the sludge cover treatment method of the present invention. .

Referring to these drawings, first, sludge such as sewage treatment sludge is stored in the sludge storage 10 of the sludge treatment plant, and a predetermined amount is carried into the storage hopper 11 (100). Sludge is first mechanically pressed in a sewage treatment plant to remove some moisture, and contains about 80 to 85% of water on average and 50% of organic matter when dried. A certain amount of sludge supplied to the storage hopper 11 among the sludges introduced is introduced into the mixer 25 by the feeder 12 (230), and the mixing stirring 250 is started to form the mixing step 200.

The mixer 25 is, for example, a kind of large container having an effective capacity of about ³ m ³ , and a paddle stirrer is installed inside the mixer to mix chemicals of 1 to 2 tons. Usually, a pin mill (not shown) is provided on the stirrer for pulverizing agglomerated materials among the input materials. The upper portion of the mixer is opened so that the treatment material for sludge and sludge treatment is introduced through the opening (210).

Sludge treatment materials have been developed and used in the past.

In the present embodiment, as a treating material, a solidifying agent and a hardening agent are used, and as a solidifying agent, powdery quicklime (calcium oxide: CaO), calcined gypsum (calcium sulfate hemihydrate: CaSO ₄ 1 / 2H ₂ O), ferrous sulfate (FeSO ₄ ) Is mainly used, and as a hardener, cement such as porcuran cement may be used alone or in a state where cement and quicklime are mixed, but quicklime is used here. The solidifying agent and the curing agent are introduced into the mixer 25 through a meter in the solidifying agent reservoir 21 and the curing agent reservoir 23, respectively.

In general, the most important reactions in sludge cover work are the hydration of quicklime, the hydration of acidic substances in solidifying agents, the neutralization of basic and acidic substances, the hydration of cements, and curing.

Hydration of Quicklime

CaO + H 2 O → Ca (OH) 2 + 15 ㎉ / mol

Quicklime contained in the solidifying agent plays a role of primarily reducing moisture in sewage sludge by hydration reaction when mixed with sewage sludge. Absorbs about 320g of water per kilogram of quicklime and releases about 280㎉ of heat to evaporate 450g of water.

Hydration reaction of cement (water content decrease, strength and dissolution inhibition)

2 (3CaO SiO2) + 6H2O → 3CaO 2SiO2 3H2O + 3Ca (OH) 2

Cement becomes hydrated when it comes into contact with water, turning it into a silica material. At this time, moisture in sewage sludge is absorbed, the strength of solids is gradually increased, and elution of sewage sludge is also suppressed.

Neutralization

H + (αｑ) + OH- (αｑ) → H2O (ℓ)

Neutralization reaction is a reaction in which a low pH acid and a high pH base react to neutralize the pH. The acid component in the solidifying agent and the alkali component in the solidifying agent react to change into neutral compounds, and the produced moisture is changed into water vapor due to the heat of reaction.

Basically, in order to be used as cover material in the state treated with hardener and hardener, certain requirements related to acidity (ph concentration) must be satisfied, and hardener and hardener to keep the environment workable by preventing severe odor even in the process of treatment. The chemical composition and its dosage should be controlled. Many components and compositions are already known for treatment materials for sludge treatment. In this embodiment, the acid and alkali components are used together in the treatment material, and the solidification agent 250t to 350t produced by Hankook Pozotech Co., Ltd. is a hardener 50t to 100t with respect to 1000t (ton) of daily treatment capacity sludge in the loaded state. Used.

Typically, the base material to be treated in the treatment apparatus through chemical stirring is put first, and then the treatment chemicals are put into the agitation, and the conventional slurry treatment apparatus has been followed to this process to date. However, in the present embodiment, the treatment material is first introduced in consideration of the characteristics and throughput of the sludge, and then the sludge is added later. Since the sludge has a large amount of water input into the mixer at one time, in the present embodiment, the sludge input mode that takes some time to input is fully considered, and the sludge contains physical properties such as mud dough containing about 80% of water. Considered.

When the sludge is added first, the reaction time between the water and the treated material of the sludge reacts for a few minutes and the heat released is small. The temperature of the mixture is low, and the mixed state in the mixture is generally uneven, resulting in a lot of sludge but agglomeration and where the treatment material remains in powder form. Therefore, as a whole, there are many places where particle formation is not performed properly. Moreover, the agitation degree is also easy to fall by the characteristic of the conventional apparatus in which a stirring blade is lower.

If simply increasing the stirring time to compensate for this problem there is a problem that the treatment material powder is mixed evenly with the sludge. The treatment material absorbs the water of the sludge upon mixing with the sludge, producing hydrate crystal grains with a larger particle size than the original powder, but when mixed with the sludge too evenly, it is difficult to produce such large particles, and the whole mixture is still It becomes like a wet mud dough. The mixture in this state becomes more difficult to handle because of its tendency to retain moisture in subsequent processes. Therefore, simply increasing the stirring time of the sludge and the treatment material has a limitation through the mixing of the sludge and the treatment material.

The inventor of the present invention, if the treatment material is first introduced as in the present embodiment, the moisture and the treatment material can be obtained for a time to react even before stirring while the sludge is added, and the stirring temperature due to the release of calories at this time can be increased, It has been found that it is possible to form a suitable state of agitation, such as soil dough or lumps, which are brittle rather than mud dough while retaining moisture without increasing the agitation time.

Therefore, in the present embodiment, the treatment material is first introduced into the mixer 25 in consideration of the characteristics and throughput of the sludge, and the sludge is transferred and introduced in the state (230). Since the amount of sludge once introduced into the mixer 25 is more than 0.5 ton, the sludge input time takes 2 to 4 minutes, and during this period, the water of the sludge first introduced is treated while reacting with the treatment material to generate heat. The change of the ash state and the change of the sludge state begin. The treatment and sludge input to the mixer is not a continuous flow method in which the input and discharge are continuously, but is a batch type, and after mixing a certain amount of material into the mixer, the mixer is opened and the mixture is discharged at once to empty the mixer. The next cycle is to prepare the mix.

When the sludge is added, the paddle stirrer is operated at a speed of about 30 revolutions per minute, and the sludge and the processing material are stirred for an average of 30 seconds for 20 to 40 seconds, and a predetermined time such as 30 to 60 seconds is allowed in the mixer. Allow for further chemical reactions. This agitation allows the treatment material powder and sludge to mix, so that the state of the mixture as a whole is mixed relatively evenly within a realistic range.

The sludge, treatment material mixture is transferred from the mixer to the mixture storage hopper 31 as a whole, and is partially transferred from the mixture storage hopper 31 through the conveying means 33 such as a screw conveyor and a belt conveyor (300). Input to the inlet or opening of the upper curing machine (410). In the process of transport, the mixture develops widely in a certain development section 37 to have an opportunity to release internal moisture and gas, and the moisture of the treatment material and sludge continues to react after mixing, and the mixture is slightly more different from the mud dough. It becomes a state of soil containing moisture which can be differentiated, and the heat releases some water and gaseous components of the sludge. Storage hoppers and transport means are installed in compartments to prevent odors from being released into the open atmosphere, in which the space is filled with gases and vapors released from the sludge. By quickly venting and removing vapors and gases from this space, it increases the chances of dropping the sludge's water content on the one hand and, on the other hand, prevents the gas from being released into the atmosphere untreated. To this end, an exhaust duct is installed with a separate exhaust device to be connected to the mixture transport space. The inlet of the exhaust duct may be installed at the final end of the development section 37 of the partitioned space, wherein the inlet duct inlet is at least 30 cm away from the mixture and partly dried or partially agglomerated and powdered quicklime Do not allow lamps to enter the exhaust duct. The exhaust duct creates a negative pressure through the exhaust pump 35 to suck moisture and other exhaust gases from the space where the mixture is transported and to move through the exhaust line so that the exhaust gases can be condensed and deodorized with water vapor.

In this embodiment made through the same step as shown in Figure 4 by the conveying means 33, the mixture is introduced into the first mixture curing machine 41a in a state of about 57% to 65% water content (610).

The container-type body 141 of the curing machine 140 has an inlet or an opening into which the mixture is introduced, and has a steam outlet 615 through which water vapor and gas are discharged. The steam outlet 615 is connected to the exhaust line 611, the exhaust pump 613 is installed in the exhaust line 611 is forced to discharge the steam quickly, preferably to make the inside of the negative pressure to increase the efficiency of steam discharge It is configured to be. At this time, the steam outlet 615 is at least a certain distance α, for example, 30 cm from the mixture to be brought into the curing device, so that the particles that are partly dried and partly agglomerated in the form of powder are not introduced into the exhaust duct.

In the present invention, a dispersing device 147 for dispersing the mixture is installed below the inlet through which the mixture is introduced in the curing machine. In the step of entering the upper part of the main body of the curing machine, although the mixture can identify the particulate matter, the water content is high, so that a large part of the particles may fall toward the bottom of the container-type body 141 in the form of agglomerated soil. . Therefore, the dispersing device 147 divides the mixture in the form of a soil mass into smaller particle stages from the initial stage of inputting, and can fall from the inner space of the container-type body 141 of the curing machine in a wide spread state. (620).

In the present embodiment, the dispersing device 147 is formed by installing a plurality of pins 473 protruding from the surface of the cylindrical roller 471 and installing the rotating support 475 similarly to the rotary threshing machine. Bearing devices can be provided for smooth rotation. At this time, the cylindrical roller 471 is rotated by the impact force of the mixture falling through the opening to the one side or the power of a motor or the like without a separate rotational power of the mixture in the state of the mass to the protruding pin 473 of the surface May be scattered into the space of the container body.

In the conventional sludge treatment apparatus, the mixture introduced into the curing machine 140 was in a state close to the wet mud dough, and the mixture was introduced into the curing machine 140 to blow hot air in a state where a certain amount was filled in the curing machine for several hours or more. Since storage and curing were carried out, it was neither necessary nor easy to disperse the mixture when it was introduced at the inlet of the curing machine. However, by the new method, the mixture introduced into the curing machine is predominantly grained rather than kneaded, so that the mixture can be easily scattered inside the container-type body of the curing machine through the dispersion device.

Inside the container type body 141 of the curing machine 140, a plurality of pipes 431 provided with a plurality of hot air spray nozzles 437 are formed in a plurality of layers in order to contact the hot air evenly to the mixture falling in a dispersed state. Are distributed vertically or vertically. The hot air is made through the hot air device 143 provided in the curing machine. The hot air device 143 uses the hot air pipe 431 to heat the heated compressed air in a state in which the heated compressed air made through the blower 433 and the heaters 435 and 43a is evenly distributed in the container-type body space of the curing machine through the hot air pipe. Hot air is supplied by discharge | emission through the nozzle 437 provided in this.

The mixture introduced at the inlet of the mixture curing unit 141 is similar to the soil (soil or lump of soil) with moisture, and the pipe is disposed in the interior space during the fall or the resistance of the air in addition to the dispersing device, while falling from the top to the bottom. It can also fall into smaller clumps or particles as it collides with or collides with upward hot air. The surface area exposed to the outside air of these mixtures is further increased, and the moisture on the surface becomes water vapor due to the hot air, and thus the moisture content of the mixture is lowered to dry (630).

The curing machine may pass through the mixture only once but may be subjected to a plurality of times more than two times for sufficient drying, and in the present embodiment, the mixture may be passed through the first mixture curing machine 41a followed by the first mixture curing machine 41a. The 2nd mixture curing machine 41b which inject | pours the obtained mixture (henceforth a "solidified substance") is further provided. Therefore, the resulting solid obtained by passing the mixture through the first mixture curing machine 41a is fed to the second mixture curing machine 41b again by the transfer device to further dry by hot air.

Here, the first mixture curing machine 41a is composed of two individual curing machines installed in parallel with each other, and the second mixture curing machine 41b is composed of three individual curing machines installed in parallel with each other, but the first mixture curing machine or the first mixture The specific number and capacity of the individual curing machines that make up the curing machine depend on these factors as they depend on the water content required for the material processed through the curing machine, the processing time in each stage curing machine, and the capacity of the hot air device. .

For example, the blower air is 20 degrees Celsius room temperature and 60% relative humidity inhaled in a normal atmosphere, and the temperature of hot air is controlled at 100 degrees Celsius in the range of 80 degrees Celsius to 100 degrees Celsius. The air discharged through the steam outlet becomes air having a relative humidity of 95% at a temperature of 65 ° C., and the moisture content of the material introduced into the first mixture curing unit 41a is 65%, and the second mixture curing unit 41b is Assuming that the water content of the coarse output 40% is to be a first mixture curing groups is made by installing a three separate curing of 120m ³ volume in parallel, the second mixture in parallel groups of two separate curing of 120m ³ volume quantity produced The operating plan may be made such that the capacity of the blower to supply hot air in these curing machines is 20 to 24 m ³ per minute for all individual curing machines.

In this case, the size (height) of the first mixture curing machine 41a, which is the first curing machine, and the second mixture curing machine 41b, which is the second curing machine, varies the hot air temperature, and the amount of air flowing through the nozzle, The treatment time and treatment method of the mixture curing machine 41a and the second mixture curing machine 41b which is the secondary curing machine may be different, so that a more suitable treatment may be performed on the mixture or solids.

The dispersing device 147 of the curing machine may be used only for the first mixture curing machine or only for the second mixture curing machine depending on the state of the injected material, but it is preferable that the dispersing device is installed in every individual curing machine that forms the mixture curing machine. However, the dispersing device of the first mixture curing machine is mainly used for dispersing the mixture which is weakly lumped by water, and the dispersing device of the second mixture curing machine is mainly for crushing the dried solids in agglomerated state. . Accordingly, the configuration or type of the dispersion device used in the curing machine may also vary. For example, the first mixture curing machine does not have a separate motor for the dispersing device, and strikes the mixture on one side of the dispersing device made of cylindrical rollers having a plurality of pins on the surface thereof, and the dispersing device is rotated at a low speed by the impact, and the second mixture In the curing machine, it is possible to use a dispersing device which is rapidly rotated by a motor (not shown) to crush and crush the masses which are partially dried and harden to each other.

The curing machine 141 is formed in a container shape having a height (6 m to 8 m) higher than the average width (for example, 4 m x 4 m) or diameter of the container such as a tower so that the mixture can be sufficiently separated and dried while falling. It is preferable. The hot air nozzle 437 formed of a hole formed in the hot air pipe may be opened as it is or may have a cover member thereon.

The mixture that is dried by the hot air and dropped on the bottom of the main container of the curing machine is a discharge device 145 or curing machine including a feeding screw (453: 45a) that rotates continuously, a motor (451), a bearing (455), etc. to rotate it. Collected by a funnel structure with an inclination implemented in the container-shaped body of the collected and can be continuously discharged out of the curing machine at the same time (640). Purely drying the first mixture curing machine 140 takes a short time of about a few minutes, it may take only a few tens of minutes to process the same amount filled in one batch of curing machine. In this way, the first curing step is performed (600a).

The resultant solids discharged to the outside through the discharge device of the first mixture curing machine are introduced into the upper opening of the second mixture curing machine through a separate transfer device. At this time, the discharge passage is blocked by the shield 148 as shown in Figure 3 inside the container-shaped body of the second mixture curing machine, while one side is introduced and dropped through the upper opening, one side is stacked and stacked at the bottom. In this process, the hot air is continuously supplied through the nozzle, and a hybrid drying process of drying the solids falling on the floor and the solids loaded on the floor is performed (650).

When a predetermined amount of one batch is loaded in the second mixture curing unit, a loading drying process is performed in which hot air is supplied and dried only for the loaded solids without falling solids (660). The loading drying process may vary depending on the moisture content requirement of the solids to be discharged, and may be assumed even when there is no separate loading drying process that usually follows several hours or a hybrid drying process.

When the drying is performed by hot air treatment, the shield is opened and the solids loaded on the second mixture curing machine are discharged as cover soil through the transfer screws 453 and 45b (670). This completes the second curing step (600b), the curing step 600 is terminated.

Here, as shown in FIG. 1, the first mixture curing device and the second mixture curing device are installed in series with each other in series, but after one step curing process is completed, the first curing device is finished, and the same curing device is used to feed solids in the form of a feedback bag. The second stage curing process may be performed. Thus, the plant can be flexibly operated depending on whether the number of curing units is sufficient or insufficient for the sludge treatment capacity.

In the embodiment of FIG. 5, the curing step 500 is performed by omitting the first curing step 600a in the embodiment of FIG. 4 and including only the second curing step 600b. That is, the curing step is all made in a single stage curing machine, it is made by applying a hybrid drying process 510, loading drying process 520, discharge process 530 sequentially or in series. In this case, a method of reducing the mixing rate of the hybrid drying process and increasing the time of the loading drying process may be used to lower the moisture content.

In the embodiment of FIG. 6, the curing step 400 is performed in both stages of the single step as in the embodiment of FIG. 5, but only the hybrid drying process 410 and the discharge process 430 have no loading drying process. Therefore, hot air drying is performed only once until one batch of the mixture has dropped all to the curing machine through the upper opening, and immediately after the mixture has dropped, the shield of the outlet is opened and the mixture is discharged. In this example, the number of curing machines can be reduced, which may be advantageous in terms of equipment cost.

Meanwhile, steam and gas generated at all stages of sludge treatment, such as the original sludge, mixer, and curing machine, are harmless to the environment through a separate deodorization tower 61 and a condenser (not shown) for condensation and deodorization treatment. May be discharged. Derivative 63 represents a wastewater reservoir for storing condensate obtained through the condenser.

In the present embodiment, the solidified mixture discharged from the second mixture curing machine 41b is collected in the discharge air hopper 51, and the discharge air hopper 51 opens the lower discharge port to load the mixture on a vehicle or the like. At this time, the solidified mixture discharged from the curing machine has a very small and fragile particle group or is taken out as a soil composed of individual particles, and is easily broken even if there is a lump by its own pressure.

The solidified mixture loaded on the vehicle forms the soil covering the surface of landfill and the like is completed.

In the above embodiment, in order to increase the sludge throughput, the processing capacity of the mixer, curing device, and feeder can be designed large, and the mixing device and curing device having a certain unit processing capacity can be connected in parallel to design an appropriate capacity for each step. Even sludge treatment can be performed without any phenomena.

1 is a simplified block diagram showing one embodiment of an apparatus for sludge cover suitable for the method of the present invention;

FIG. 2 is a schematic cross-sectional view of one embodiment of a curing machine such as used in the apparatus of FIG.

Figure 3 is a cross-sectional view showing a hybrid drying step made according to the method of the present invention in the curing machine,

4 to 6 are flowcharts showing the steps of three different embodiments of the sludge cover treatment method of the present invention.

Claims (5)

In the sludge cover treatment method comprising a mixing step of mixing the sludge and the treatment material to form a mixture and a curing step of putting the mixture into the curing machine and drying through hot air, The curing step is made by connecting the first curing step and the second curing step in series (series), In the first curing step, the input process of dropping the mixture of the sludge and the treatment material mixed in the mixing step into the container-type body through the upper opening, the drying of the mixture dropped through the hot air discharged from the inside of the container-type body Drying process, and the discharge process to immediately discharge the mixture dropped on the bottom of the container-type body out of the curing machine is made, In the second curing step, the mixture passed through the first curing step is dropped into the container-type body through the upper opening, and the hot air is continuously supplied while the mixture that has been dropped for a predetermined period is not discharged from the container-type body. Sludge cover treatment, characterized in that it comprises a hybrid drying process for drying the mixture falling in the container-type body and the mixture in the drop-loaded state and the discharge process for discharging the mixture loaded in the container-type body to the outside Way. The method of claim 1, Next to the hybrid drying process, the sludge cover treatment method further comprises a loading drying process for drying only the mixture in a loaded state with hot air without falling of the mixture. The method of claim 1, In the hybrid drying process, the sludge cover treatment method is characterized in that the mixture is dispersed to disperse through the dispersing apparatus to fall in the container-type body in a dispersed state. The method of claim 1, The mixing step is a sludge cover treatment method characterized in that the treatment material is first introduced through the mixer vessel upper opening and then the sludge is added and then stirred through a stirring device in the mixer vessel. delete

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