JP2020001019A - Method and apparatus for treating organic waste - Google Patents

Abstract

To measure at least one of dehydrated and dried organic waste and measure a water content thereof with high accuracy.SOLUTION: A method for treating an organic waste has a measurement process in which a series of operations are performed continuously, such as: continuously collecting a dewatered product of an organic waste discharged from an outlet of a dehydrator 3; compacting and condensing it; and thereafter measuring a water content by microwave, and also has a measurement process in which a series of operations are performed continuously, such as: continuously collecting a dried product of the organic waste discharged from the outlet of a dryer 5; compacting and condensing it; and thereafter measuring a water content by microwave.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method and an apparatus for treating organic waste.

  In general treatment of organic waste, organic waste is dehydrated using a dehydrator, and is treated as landfill treatment or industrial waste. In recent years, it has been effectively used as a fuel resource by performing drying and carbonization treatment.

  In the drying process, the dried matter and the exhaust gas (heat medium gas or carrier gas) are discharged from the dryer in a mixed state. This mixture is separated into a granular material and a separation gas using a solid-gas separator, and the separated gas is released to the atmosphere through a deodorizing step and a dust collecting step.

  In the operation of a dehydrator or a dryer, it is desired to measure the water content of the dehydrated or dried product. By measuring the water content, for example, dehydration conditions and drying conditions can be changed, and the water content of the dehydrated product and the dried product can be kept constant. In addition, when there is no variation in the water content, it becomes easier to sell dehydrated and dried products as fuel resources. In addition, by measuring the water content, the operation is optimized, the consumption of chemicals and electric power is suppressed, and economical operation management becomes possible.

  As an apparatus and a method for measuring the moisture content of a dehydrated product, there is one disclosed in Patent Document 1 below. The device according to Patent Literature 1 has a microwave moisture content meter disposed in a dewatered cake discharge part of a continuous press-in dewatering machine, and discharges a dehydrated cake between a pair of transmitting and receiving antennas provided to face the microwave moisture content meter. A part of the condensed dewatered cake is continuously passed through to measure the water content of the dewatered cake directly and continuously.

  Patent Document 2 below discloses a device and a method for measuring the water content of a dehydrated product and performing control based on the measured value. Patent Document 2 discloses that a water content meter is arranged at a cake discharge part of a screw press to measure the water content, and when the measured water content of the dewatered cake deviates from a reference water content, rotation of the screw shaft of the screw press is performed. It is an invention that changes the number and the injection rate.

Japanese Patent No. 4342478 Japanese Patent No. 480380

  The measuring devices according to Patent Literatures 1 and 2 target only a dehydrated cake passing through a small space between a pair of transmitting and receiving antennas, and the moisture content of most of the dehydrated cake not passing through the space is unknown. is there. Estimating the water content thus measured as the water content of the entire dewatered cake has a problem in terms of accuracy.

  In addition, when the dewatered cake adheres and clogs between the pair of transmitting and receiving antennas, the clogged dewatered cake is continuously measured, and there is a problem that the water content of the flowing dewatered cake to be measured is not known.

  Therefore, a main object of the present invention is to measure at least one of a dehydrated product and a dried product of an organic waste, and measure the water content of the target with high accuracy. A further object of the present invention is to control at least one of dehydration conditions and drying conditions based on the measured value of the water content to achieve a uniform water content.

The present invention that has solved the above problems is as described below.
<First aspect>
It has a measuring step of continuously performing a series of operations of continuously collecting dehydrated organic waste discharged from an outlet of a dehydrator, consolidating, and measuring a water content by a microwave. Organic waste treatment method.

(Effect)
In the present invention, the dehydrated product is collected after being discharged from the dehydrator. The dehydrated product tends to disperse as it exits the dehydrator. For example, when an in-machine centrifugal dehydrator is used as the dehydrator, when the dehydrated product is discharged from the outlet of the dehydrator, it is discharged from the dehydrator having a gravitational acceleration of 2000 to 3000 G into the atmosphere (that is, 1 G atmosphere). As a result, the dehydrate is dispersed. By collecting the dehydrated material in a dispersed state in this way, a more objective measurement result can be obtained than in Patent Documents 1 and 2. That is, in Patent Documents 1 and 2, since a dehydrated cake passing through a small space between a pair of transmitting and receiving antennas is measured, the measured value may not indicate the water content of the entire dehydrated product. In addition, when the dewatered cake is clogged in the dewatering machine, a problem occurs in the measurement of the water content. If a problem occurs in the measurement of the water content, it becomes difficult to properly control the operation of the dehydrator. Furthermore, since the type of dehydrator is specified, a centrifugal dehydrator that can operate more efficiently cannot be used. In the present invention, the above-mentioned problems of Patent Documents 1 and 2 are solved, and highly accurate measurement of the water content becomes possible. At the same time, a centrifugal dehydrator can be employed for efficient operation.

  Also, by continuously performing a series of operations of "collecting the dehydrated material, consolidating and measuring by microwave", when the moisture content of the dehydrated product discharged from the outlet of the dehydrator changes, The change can be quickly detected. That is, a method of periodically sampling the organic waste discharged from the dehydrator and measuring the water content is also conceivable, but in this case, a change in the water content during the period when no sampling is performed cannot be detected. Therefore, such inconvenience can be solved by performing the continuous operation as in the present invention.

<Second aspect>
Having a measuring step of continuously performing a series of operations of continuously collecting dried matter of the organic waste discharged from the outlet of the dryer and measuring the water content by microwave after consolidation. Organic waste treatment method.

(Effect)
The same operation and effect as in the first aspect are obtained by continuously performing a series of operations of collecting the dried product after being discharged from the dryer, collecting the dried product, compacting, and measuring by microwave. Can be obtained.

<Third aspect>
Collection of the dehydrated product,
The method of treating organic waste according to the first aspect, wherein the dewatered product is extracted by extracting a part of the dewatered product while moving in a flow path connected to the dehydrator.

(Effect)
For example, in the case of a system for storing dehydrated material in a storage tank, even if the dehydrated material stored in the storage tank is collected and the water content is measured, the dewatering effect of the dehydrator cannot be confirmed in real time. There's a problem. By collecting the moving dehydrated material as in the present invention, there is an effect that the dehydration effect can be confirmed in real time.

<Fourth aspect>
Collection of the dried product,
The method for treating organic waste according to the second aspect, wherein a part of the dried product is extracted while the dried product moves through a flow path connected to the dryer.

(Effect)
By extracting a part of the dried product moving through the flow path, the same operation and effect as in the above (3) can be obtained.

<Fifth aspect>
An organic waste treatment device having a measurement device for measuring the water content of dehydrated organic waste,
The measuring device comprises:
A collecting unit for continuously collecting the dehydrated product,
A consolidation unit for consolidating the collected dehydrated product,
An apparatus for treating organic waste, comprising a measuring unit for measuring the moisture content of the compacted dehydrated product by microwaves.

(Effect)
The same operation and effect as those of the first aspect are obtained.

<Sixth aspect>
An organic waste treatment device having a measuring device for measuring the water content of dried organic waste,
The measuring device comprises:
A collecting unit for continuously collecting the dried product,
A consolidation unit for consolidating the collected dried product,
An organic waste treatment apparatus, comprising: a measuring unit for measuring the moisture content of the compacted dried product by microwave.

(Effect)
The same operation and effect as those of the second aspect are obtained.

<Seventh aspect>
The organic waste treatment device has a pipe connected to an outlet of the dehydrator,
The sampling unit of the measuring device is inserted inside the tube,
A moving speed of the dehydrated material moving inside the tube is in a range of 0.5 m / s to 150 m / s;
The organic waste treatment apparatus according to the fifth aspect, wherein an insertion area of the sampling unit with respect to a cross-sectional area of the pipe is 0.05% to 5%.

(Effect)
When the moving speed of the dehydrate is within the general range of 0.5 m / s to 150 m / s, if the insertion area of the sampling part is smaller than 0.05%, the amount of the dehydrate is small and the predetermined amount Since the measurement cannot be started until the dehydrate is accumulated, there is a problem that it is difficult to detect the water content of the dehydrate in real time. Further, when the insertion area of the sampling section is larger than 5%, the amount of dehydrated matter collected increases, and there is a problem that the dehydrated matter is likely to be clogged inside the measuring device.

  Therefore, in the present invention, by setting the moving speed of the dehydrated product and the insertion area of the collection unit within the above range, the amount of dehydrated product can be optimized, and the occurrence of each of the above problems can be prevented. .

<Eighth aspect>
The organic waste treatment device has a pipe connected to an outlet of the dryer,
The sampling unit of the measuring device is inserted inside the tube,
A moving speed of the dried material moving inside the tube is in a range of 0.5 m / s to 150 m / s;
The organic waste treatment apparatus according to the sixth aspect, wherein an insertion area of the collection unit with respect to a cross-sectional area of the pipe is 0.05% to 5%.

(Effect)
With respect to drying, the same operation and effect as in the seventh aspect are exhibited.

  According to the present invention, at least one of a dehydrated product and a dried product of an organic waste can be measured, and the water content of the target can be measured with high accuracy. Further, based on the measured value of the water content, at least one of the dehydration conditions and the drying conditions can be controlled, and the water content can be made uniform.

It is a flow figure of the processing method of the organic waste concerning the present invention. It is a plane sectional view of a pipe and a measuring device. It is a perspective view of a sampling part.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Note that the following description and drawings merely show one embodiment of the present invention, and the contents of the present invention should not be interpreted as being limited to this embodiment.

  FIG. 1 is a flowchart of a method for treating organic waste W as an example of the present invention. The organic waste W treatment apparatus 1 includes a dehydrator 3, a hot air generator 4, a continuous hot air dryer 5, a solid-gas separator 6, and the like. Hereinafter, the configuration and the processing flow of the processing apparatus 1 will be described in detail.

(Organic waste W)
The processing apparatus 1 is for processing the organic waste W. Examples of the organic waste include sewage sludge (including surplus sludge, primary sludge, mixed raw sludge, mixed sludge, digested sludge, sludge mixed and digested with biomass), wastewater treatment sludge, papermaking sludge, and activated sludge. , Building pit sludge, agricultural settlement drainage sludge, and other organic sludge. Among these sludges, it is particularly suitable for treating sewage sludge. In addition, the organic waste W includes one in which an inorganic substance is mixed.
The organic waste W is stored in the organic waste storage tank 2, and is supplied to the dehydrator 3 by the supply pump 21.

(Dehydrator 3)
The processing apparatus 1 has a dehydrator 3 for dehydrating the organic waste W. In the embodiment of FIG. 1, the organic waste W is sent to the continuous hot-air dryer 5 after being dehydrated by the dehydrator 3.

  Examples of the dehydrator 3 include a centrifugal dehydrator, a belt press dehydrator, a screw press dehydrator (including a multi-plate type dehydrator), a rotary press dehydrator, a rotary press dehydrator, and a multiple disk dehydrator. Can be mentioned. Among these dehydrators, a centrifugal dehydrator is particularly suitable.

  The centrifugal dehydrator 3 includes a dehydrator used in a two-liquid refining method in which two types of coagulants are added to organic waste W and the properties of the organic waste W are adjusted. This two-liquid refining type centrifugal dehydrator can easily reduce the maximum particle size and the average particle size of the dehydrated product. There are two-liquid refining type centrifugal dewatering machines, two-liquid refining type centrifugal dewatering machine inside the machine and two-liquid refining type centrifugal dewatering machine outside the machine. The former is two kinds of coagulant (one is inorganic coagulant , And another type is a polymer flocculant. The same applies hereinafter.) Is a dehydrator that supplies sludge inside the machine, and the latter is a dehydrator that supplies two types of flocculant to sludge outside the machine. In the present invention, either type may be used.

  The two-liquid refining type centrifugal dehydrator 3 is provided with a rotating bowl on the outside, and a screw conveyor is provided in the rotating bowl. A supply port is provided at one end of the rotating bowl, and a discharge port is provided at the other end. The organic waste W supplied from the supply port into the rotary bowl is conveyed to the other end while being stirred by the screw conveyor, and is discharged from the discharge port as dehydrated material. The organic waste W is dehydrated by the centrifugal force generated by the rotation of the rotating bowl in the process of moving from one end to the other end in the rotating bowl.

  The in-machine two-liquid refining type centrifugal dehydrator 3 adds the polymer coagulant HC and the inorganic coagulant IC to the organic waste W by injecting them into the rotating bowl. On the other hand, the external two-liquid refining type centrifugal dehydrator 3 adds the polymer flocculant HC and the inorganic flocculant IC to the organic waste W before being supplied to the rotating bowl.

  As the polymer flocculant HC, for example, a polyacrylamide-based or polyacrylate-based one can be used. Examples of the inorganic coagulant IC include, for example, ferric sulfate (particularly, ferric polysulfate (polyiron)), ferrous sulfate, ferric chloride, aluminum sulfate and polyaluminum chloride (PAC), and ferric chloride. Etc. can be used. By using these two types of coagulants, the maximum particle size and the average particle size of the dehydrated product can be reduced. In addition, the water content of the dehydrated product can be reduced.

It is preferable that the injection rate of the inorganic coagulant IC is 5% or more with respect to the solid amount of the sludge supplied to the dehydrator 3. For example, when the amount of solid matter of the sludge supplied to the dehydrator 3 is 4 m ³ / h, it is preferable to inject an inorganic coagulant IC of 0.2 m ³ / h or more. By injecting 5% or more of the inorganic coagulant IC, the properties of the dehydrated material become suitable for drying of the continuous hot air dryer 5, and the dehydrated material adheres to the continuous hot air dryer 5, Can be prevented.

As described above, the more the injection rate of the inorganic coagulant IC is set to more than 5%, the more difficult it is for the dehydrate to adhere and accumulate in the continuous hot-air dryer 5.
However, as the amount of the inorganic coagulant IC increases, the chemical cost increases. In addition, depending on the type of the inorganic coagulant IC, sulfur and hydrogen chloride are volatilized from the inorganic coagulant IC to lower the acid dew point, and the sulfuric acid and hydrochloric acid contained in the inorganic coagulant IC are dissolved out. Corrodes the interior of the In consideration of these disadvantages, the injection rate of the inorganic coagulant IC is preferably set to 30% or less.

  By injecting the inorganic coagulant IC, the water content of the dehydrated product can be reduced. For example, when the injection rate of the inorganic coagulant IC is 5% to 30%, the water content of the dehydrated product can be about 75% to 79%.

  In addition to the inorganic coagulant IC, a polymer coagulant HC is injected into the two-liquid refining type centrifugal dehydrator 3. Like the inorganic coagulant IC, the polymer coagulant HC has a function of coagulating sludge. Therefore, the injection rate of the polymer flocculant HC is preferably changed according to the injection rate of the inorganic flocculant IC. For example, when the injection rate of the inorganic flocculant IC is 5% to 30%, the injection rate of the polymer flocculant HC is about 0.1% to 5% with respect to the solid amount of the sludge supplied to the dehydrator 3. Is preferable.

  Examples of the in-machine two-liquid refining type centrifugal dehydrator include, for example, “Technical Information / Research”, “133 No. 2012/12/13 Technical Information <Technical Information” on the website of the Japan Sewage Works Agency of Japan, April 20, 2015. Introduction> "Two-liquid refining type centrifugal dewatering machine in machine"-Realization of low moisture content dewatered sludge "column can be used.

  When the in-machine two-liquid refining type centrifugal dehydrator 3 is used, when discharged from the outlet of the dehydrator 3, the gravity acceleration from the dehydrator 3 having a gravitational acceleration of 2000 to 3000 G is performed in the air, that is, 1 G. , The dehydrated product is dispersed. Therefore, it is easy to uniformly collect the dehydrated material discharged from the in-machine two-liquid refining type centrifugal dehydrator 3. At the same time, the properties of the dehydrated material suitable for drying by the continuous hot-air dryer 5, particularly the particle size of the dehydrated product, can be easily adjusted to a desired range.

  Further, the one-component refining type centrifugal dehydrator 3 may be used. In that case, either of the in-machine one-component refining type centrifugal dehydrator 3 and the out-of-unit one-component refining type centrifugal dehydrator 3 may be used. good. When using the one-component refining type centrifugal dehydrator 3, only the inorganic coagulant IC is injected without injecting the polymer coagulant HC. The injection rate of the polymer flocculant HC is the same as in the case of the two-liquid refining type centrifugal dehydrator 3. Specifically, the amount of solid matter of the sludge supplied to the dehydrator 3 is preferably 5% or more, and the injection rate of the inorganic coagulant IC is more preferably 30% or less.

(Dehydrated material transfer machine 7)
The sludge (dehydrated product) discharged from the dehydrator 3 is supplied to the dehydrated product transporter 7. The water content of the dehydrate is preferably 81% or less, more preferably 78% or less. When the water content is higher than 81%, the dehydrated substance easily adheres to the inside of the continuous hot-air dryer 5, and the dehydrated substance may be clogged. In the configuration of FIG. 1, the dehydrator 3 and the dehydrated substance transporter 7 are connected by a pipe 30, and the dehydrated substance moves to the dehydrated substance transporter 7 through the inside of the pipe 30.

  A screw conveyor or a belt conveyor that conveys by mechanical power can be used as the dewatered material conveyor 7. In FIG. 1, a screw conveyor is used as the dehydrated product transporter 7. Further, a supply port is provided at a longitudinally intermediate portion (near the center) of the screw conveyor 7 in FIG. 1, and the dehydrate is supplied into the screw conveyor 7 from this supply port.

(How to supply dehydrated material)
When supplying the dehydrated product to the continuous hot-air dryer 5, the supply amount (kg-ds / min) of the dehydrated product to the continuous hot-air dryer 5 is represented by X, and the retained amount of the dehydrated product of the continuous hot-air dryer When (kg-ds) is Y, continuous hot air drying is performed so that the average residence time T during which the dehydrated product defined by the following equation 1 stays in the continuous dryer is within a range of 0.05 to 10 minutes. It is preferably supplied to the machine 5.
T = Y / X Equation 1
The residence time T is preferably in the range of 0.1 to 7 minutes, and more preferably in the range of 0.2 to 5 minutes.
By setting the supply amount of the dehydrated product to the continuous hot-air dryer 5 within the above range, the time during which the dehydrated material stays in the continuous hot-air dryer 5 becomes an appropriate value, and a malodor is generated from the final product. Can be suppressed.

(Maximum particle size)
It is preferable to provide the dewatered material transporter 7 with a measuring means for measuring the particle size of sludge (dewatered material). As a result of measuring the particle size of the dehydrated product, when the maximum particle size of the dehydrated product is higher than the reference value, the dehydrated product is sent to the digestion tank 20; Send to. The reference value can be arbitrarily determined. When the maximum particle size of the dehydrate is larger than 60 mm, the reference value is sent to the digestion tank 20, and when the maximum particle size of the dehydrate is 60 mm or less, the reference value is sent to the dryer 5. Is preferable.

  When a dehydrated product having a maximum particle size of more than 60 mm is supplied to the continuous hot-air dryer 5, there is a high possibility that the dehydrated product adheres or accumulates in the dryer 5. When the amount of deposition exceeds a certain amount, it is necessary to temporarily stop the operation of the dryer 5 and artificially discharge the deposit. In the present invention, long-term continuous operation of the dryer 5 is realized by not supplying a dehydrated substance having a maximum particle size larger than 60 mm.

  The maximum particle size of the sludge was measured by the method described in JIS M8801 Coal Test Method. Sludge is actually measured visually, and the maximum diameter of the measured value is defined as the maximum particle diameter.

  When the two-liquid refining type centrifugal dehydrator 3 is used, the dehydrated product is likely to be formed into a uniform particle (granular material), and the measurement of the maximum particle size and the average particle size is easy. Therefore, the two-component refining type centrifugal dehydrator 3 is more suitable than the one-component refining type centrifugal dehydrator 3.

  The dehydrated product may not be uniform and granular, that is, the dehydrated product may be agglomerated by moisture or the like. Even if there is such a lump of dehydrated material (lump), it can be supplied to the dryer.

  When the two-liquid refining type centrifugal dehydrator 3 is used and the injection rate of the inorganic coagulant IC is set to 5% or more, the dehydrated product is more likely to be granular. By granulating the dehydrated material, it is easy to stably supply the dehydrated product to the continuous hot-air dryer 5. Further, when the dehydrated product is granular, the resistance to the hot air flowing through the continuous hot air dryer 5 is reduced, and there is an advantage that the chance of contact between the hot air and the dehydrated product can be increased.

(Average particle size)
The average particle size is measured by the following method. When the particle size of the dehydrated product is 500 microns or more, sieving is performed according to the method described in JIS M8801 Coal Test Method, and the sieving result is represented by a rosin-Rammler distribution, where the integrated mass (on the sieve) corresponds to 50%. Is determined as the average particle size. When the particle size of the dehydrated product is less than 500 microns, the particle size distribution is measured using a particle size distribution measuring device 8 (for example, a laser diffraction type particle size distribution measuring device, trade name: SALD-3100, manufactured by Shimadzu Corporation) and accumulated. The particle diameter when the volume corresponds to 50% is determined as the average particle diameter.

  The average particle size of the dehydrated product may be measured and sent to the dryer 5 when the average particle size is 1 mm to 30 mm, and sent to the digestion tank 20 when the average particle size is out of the range. When the average particle diameter is larger than 30 mm, the possibility that the dehydrated product adheres or accumulates in the dryer 5 increases, and thus such control is preferably performed. At the same time, if the average particle size is larger than 30 mm, drying may not be performed sufficiently in the dryer 5 and may be discharged, and there is a concern that the quality of a dried product as a final product may deteriorate.

(Particle size distribution)
In order to stabilize the operation of the continuous hot-air dryer 5, it is preferable to reduce fluctuations in the particle size distribution of the sewage sludge supplied per unit time. This is because a problem occurs when the value of the particle size distribution changes significantly. Specifically, when the value of the particle size distribution of the sludge increases, the moisture of the dried product discharged from the dryer 5 tends to be non-uniform, and when the value of the particle size distribution decreases, the moisture of the dried product tends to be uniform. .

(Hot air generator 4)
The dehydrated material discharged from the dehydrator 3 is sent to the continuous hot-air dryer 5 and is dried in the dryer 5 by contact with hot air. The hot air used for the dryer 5 is generated by the hot air generator 4. Specifically, the burner 4A supplied with the fuel F (LPG or the like) from a fuel tank (not shown) heats the compressed air sent from the storage tank 18 that stores the compressed air generated by the air compressor 17, and Generate hot air. When the organic waste W is sludge, a digestion gas generated when digesting sludge may be used as the fuel F. The control of the hot-air generator 4 measures the outlet temperature of the hot-air generator 4 and controls the amounts of the fuel F and the air A supplied to the hot-air generator 4 so as to reach a target temperature.

  Although the hot air temperature is not particularly limited, 5% or more of the inorganic coagulant IC is injected with respect to the amount of the solid matter of the organic waste W supplied to the dehydrator 3, and the dewatered product is dried by the dryer 5. In this case, the hot air temperature is preferably set to 250 ° C to 500 ° C. By using the hot air in this range, the water content of the dried organic waste becomes a low value of about 10% to 50%, thereby increasing the value as a product.

  The hot air temperature is more preferably 350 to 450 ° C, further preferably 390 to 410 ° C, and most preferably 400 ° C. When the hot air temperature is low, the dehydrated product cannot be dried sufficiently, and the moisture content of the dried product increases. On the other hand, when the hot-air temperature is high, the fuel cost of the hot-air generator 4 increases, and the economic efficiency deteriorates. Therefore, it is most appropriate to set the temperature at around 400 ° C. in order to balance the economics of the moisture content of the dried product and the fuel cost.

(Continuous hot air dryer 5)
The continuous hot-air dryer 5 brings the dehydrated product from the dehydrator 3 into contact with hot air from the hot-air generator 4 to dry the dehydrated product into powder and granules.

  Examples of the continuous hot-air dryer 5 include (1) a type in which dehydrates are dispersed in hot air and dried, such as a spray dryer, a flash dryer, a fluidized-bed dryer, and a rotary dryer; ) The dehydrated material is transported in a stationary state as in a ventilation band dryer, a tunnel dryer (parallel flow band dryer), a spouted dryer, etc., and hot air is brought into contact with the dehydrated material during the transport process. Examples of the drying type and (3) a drying type in which hot air is brought into contact with the dehydrated product while mechanically stirring the dehydrated product, such as a stirring dryer, can be exemplified. The “continuous” of the continuous hot-air dryer 5 means that the continuous hot-air dryer 5 can be operated continuously.

  It is preferable to use a flash dryer 5F among the continuous hot air dryers 5. This is because they are inexpensive and have excellent maintainability.

  Although there are various types of flash dryers 5F, drying the organic waste W using the indirect heating dryer 3 can weaken the adhesion of the indirectly dried product. A flash dryer 5F without a crusher for crushing can be used.

  FIG. 1 shows an example of the flash dryer 5F. The flash dryer 5F is a tubular flash dryer 5CF in which pipes through which hot air flows (hereinafter, also referred to as "pipes") are arranged in an annular shape. The illustrated tubular airflow dryer 5CF includes a pipe 5a to which the hot air sent from the hot air generator 4 first reaches, a pipe 5b extending upward from the pipe 5a, and a pipe 5b extending in a direction to be turned back from the pipe 5b. It comprises a pipe 5c extending horizontally and a pipe 5d extending downward from the pipe 5c. An R-shaped curved pipe is located between adjacent pipes (for example, between the pipes 5a and 5b). The lower end of the pipe 5d is joined to the left end of the pipe 5a, and the insides of the pipes are connected to each other at this joint. An indirect dried product supply port 5X is provided at an intermediate portion of the pipe 5a, and a dried product discharge port 5Y is provided at an intermediate portion of the pipe 5d.

  The hot air generated by the hot air generator 4 is supplied to the pipe 5a. At the same time, the indirect dried material transported by the transporting means 7 falls from the supply port 5X into the hot air (hot airflow) of the pipe 5a. The indirectly dried product that has fallen is dispersed in the form of powder in hot air. Then, the granular material is instantaneously dried while being sent in parallel with the hot air flow (while being conveyed by hot air). More specifically, the hot air accompanied by the granular material flows in the order of the pipe 5a, the pipe 5b, the pipe 5c, and the pipe 5d, and a part thereof is exhausted from the outlet 5Y to the outside. On the other hand, the indirect dried material not exhausted from the outlet 5Y merges with the hot air newly sent from the hot air generator 4, flows again with the pipes 5a, 5b, 5c and 5d, and a part thereof is discharged. The air is exhausted from the outlet 5Y to the outside of the vessel. As described above, a part of the hot air is exhausted from the outlet 5Y, and the other hot air circulates in the pipes 5a to 5d. In this way, the newly charged indirectly dried product and the indirectly dried product circulating in the tube are mixed in the tube, whereby the adhesion and the water content are adjusted. That is, in the tubular flash current dryer 5CF, the indirectly dried product is dried by absorbing heat in hot air. Therefore, the circular tube type flash dryer 5CF has a fundamentally different structure from an indirect heating dryer or the like that dries when an indirectly dried product comes into contact with a heated pipe.

  The indirectly dried product immediately after being supplied to the tubular flash current dryer 5CF often flows on the outer peripheral side of each of the pipes 5a to 5d due to the influence of the centrifugal force. Then, as the drying of the indirectly dried product proceeds, the coagulated state of the indirectly dried product is released and the average particle diameter is reduced, so that the indirectly dried product flows on the inner peripheral side of each of the pipes 5a to 5d, and the drainage provided inside the pipe 5d is formed. It is discharged from the outlet 5Y.

  In the operation of the tubular flash dryer 5CF, it is preferable that the velocity of the hot air in each of the pipes 5a to 5d be 10 m / s or more. More preferably, the speed is set to 15 m / s or more in order to smoothly transport the indirectly dried product by hot air. More preferably, the indirect dried product supplied from the supply port 5X is made to collide with the circulating hot air at a high speed, so that the indirect dried product can be dispersed in the hot air.

  FIG. 1 shows a tubular flash dryer 5CF in which the pipes 5a to 5d are formed in an annular shape. However, the continuous hot-air dryer 5 is not limited to the annular flash-dryer 5F, and may be a straight-tube flash-dryer 5LF in which all pipes are arranged linearly or substantially linearly. The circular tube type flash dryer 5CF is superior in that the installation space is smaller than that of the straight tube type flash dryer 5LF. However, even in the case of the straight tube type flash dryer 5LF, when the tubes are extended in the height direction, the installation space can be reduced.

  It should be noted that, even if the size of the tubular flash dryer 5CF is increased or decreased, there is almost no change in the residence time during which the indirectly dried product stays in the dryer 5CF.

  Instead of the continuous hot-air dryer 5, a stirring heat-transfer dryer may be used, or as the continuous hot-air dryer 5, a flash dryer with a crusher may be used. An indirect heating dryer (steam tube dryer) may be provided instead of the continuous hot air dryer 5. However, the initial cost is overwhelmingly low, the ground contact area of the equipment is not taken, and the delivery time is shortened. Therefore, a continuous hot air dryer 5 (particularly, a circular tube type flash dryer 5CF or a straight tube type flash dryer 5LF) is preferable.

The continuous hot-air dryer 5 of the present invention has a continuous hot-air dryer in which the heat capacity coefficient obtained from the size of the continuous hot-air dryer 5 and the temperature and amount of the supplied hot-air gas is in the range of 2000 to 4000 kcal / m ³ h ° C. Preferably, a dryer 5 is used. The higher the heat capacity coefficient, the more heat energy can be transmitted to the sludge, and that energy can be used for evaporating the water of the sludge. The tubular airflow dryer 5CF has an extremely high heat capacity coefficient as compared with an indirectly heated dryer such as an incline disk dryer, so that sufficient drying can be performed with a short residence time.

(Solid-gas separator 6)
The hot air whose humidity is increased by drying the granules is exhausted from the continuous hot air dryer 5 as exhaust gas and sent to the solid-gas separator 6. Since this exhaust gas contains powder and granules, the powder and granules are separated into a separation gas (gas separated from the powder and granules) using the solid-gas separator 6.

  Examples of the solid-gas separator 6 include a cyclone that collects dust by centrifugal force, a gravity settling chamber that collects dust by gravity, a mist separator that collects dust by inertia, a bag filter that collects dust by filter cloth, and filling. A moving particle layer air filter that collects dust by a layer, an electric dust collector that collects dust by electricity, and the like can be used.

(Exhaust treatment)
The separated gas separated from the granular material by the solid-gas separator 6 is removed by a venturi scrubber 11 that collects dust by washing, and then is sucked by an exhaust fan 12 and carried to a mist separator 13. Then, after being further dust-removed by the mist separator 13, the dust is deodorized by the plasma deodorizer 14 and is released into the atmosphere E. The method of treating the separated gas discharged from the solid-gas separator 6 is not limited to the above-described method, and each facility may be appropriately changed.

(Retention of powder and granules)
The granular material is discharged from the lower end of the solid-gas separator 6 and supplied to the granular material upstream transfer device 9 through the pipe 31. When the powdery material having a high moisture accumulates at the lower end of the solid-gas separator 6, the powdery material may adhere to the valve and discharge may not be performed well. Therefore, it is preferable to provide the rotary valve 19 that is scraped by the rotating blades.

  A screw conveyor or a belt conveyor that conveys by mechanical power can be used as the powdery material upstream conveyor 9. In the screw conveyor 9, the supply port of the powder and granules is provided at an intermediate portion in the longitudinal direction of the screw conveyor 9, and the discharge port of the powder and granules is connected to one end of the screw conveyor 9 in the longitudinal direction (right side in the drawing) and the like. It is provided on the end side (left side in the drawing). The granular material supplied from the supply port is conveyed to the one end by the forward rotation of the screw conveyor 9, and is discharged from the discharge port at the one end. Conversely, when the screw conveyor 9 rotates in the reverse direction, the granular material is conveyed to the other end, and is discharged from the discharge port at the other end. In addition, the temperature of the granular material supplied to the screw conveyor 9 is a high temperature of about 65C to 90C.

  The powders and granules discharged from the respective discharge ports (one end side discharge port and the other end side discharge port) of the screw conveyor 9 pass through the pipe 32 and are supplied to separate screw conveyors 10. When the screw conveyor 10 rotates forward or backward, the powder and granules are distributed to one end side and the other end side of the screw conveyor 10. The granular material discharged from the one end side discharge port or the other end side discharge port passes through the pipe 33 and is stored in each container 15 (four containers in the illustrated embodiment).

(Measurement device N)

  The measuring device N can be provided at the position of N4 or N5 downstream of the dehydrator 3 and at the position of N1 or N2 downstream of the dryer 5.

  In addition, while the measuring device N is provided downstream of the dehydrator 3 and the dryer 5, the measuring device N is provided at the position of N 6 inside the dehydrator 3 and at the position of N 3 inside the dryer 5. Is also good.

  Moreover, while the measuring device N is provided downstream of the dehydrator 3 and the downstream of the dryer 5, the measuring device N may be provided at the position of N7 upstream of the dehydrator 3 and at the position of N4 upstream of the dryer 5. .

  In addition, since the code | symbol of N1-N7 of FIG. 1 has illustrated the position in which the measuring device N is provided, it is not necessary to provide the measuring device N in all the positions of N1-N7, and the position other than N1-N7. May be provided with a measuring device N. For example, in order to measure the moisture content of the dried matter discharged from the dryer 5, the measuring device N may be provided in the pipe 32 between the granular material upstream conveyor 9 and the granular material downstream conveyor 10. Alternatively, the measuring device N may be provided in the pipe 33 between the powdery and granular material downstream transporter 10 and the container 15.

  However, it is important to measure the water content of at least one of the dehydrated product discharged from the dehydrator 3 and the dried product discharged from the dryer 5. Therefore, it is desirable to provide the measuring device N on at least one of the downstream side of the dehydrator 3 and the downstream side of the dryer 5 based on the processing step of the organic waste.

  In addition, when measuring the water content of the dehydrated substance discharged from the dehydrator 3, it is preferable to provide it at the position of N5. When measuring the moisture content of the dried matter discharged from the dryer 5, it is preferable to provide the dried matter at the position of N1. This is because the most representative portion of the sludge flowing on the process can be collected at the locations of N5 and N1.

  In addition, although not shown, the measuring device N may be provided at or near a portion where the dehydrated substance supplied from the supply port of the dehydrated substance transporter 7 falls and first lands inside the dehydrated substance transporter 7. It may be.

  In addition, in FIG. 1, the part of N7, the part of N4, and the part of N2 are also comprised by the pipe similarly to the part of N5.

  FIG. 2 shows an example of the measuring device N. The measuring device N is inserted into the inside of the tube 30 through a hole provided at an arbitrary position on the peripheral wall of the tube 30, and a sampling unit 40 that collects dehydrated or dried matter passing through the inside of the tube 30. A transport unit 41 that is disposed outside and transports dehydrated and dried products collected by the collection unit 40 to the outside, and a dehydrated product that is disposed outside the transport unit 41 and transported by the transport unit 41 is a dried product. And a measuring unit 44 disposed outside the consolidating unit 43 and measuring the moisture content of the dehydrated and dried products in the consolidating unit 43. The direction toward the center of the tube 30 is referred to as the center side, and the direction radially outward from the center of the tube 30 is referred to as the outside. The collection unit 40, the transport unit 41, the consolidation unit 43, and the measurement unit 44 are adjacent to each other in order from the center to the outside, and the dehydrated and dried products collected by the collection unit 40 are transported to the outside. . In the illustrated form, the collection unit 40 and the transport unit 41 are formed in a tubular shape, and a screw serving as a transport device 42 is disposed inside the collection unit 40 and the transport unit 41. It is in the form to move the dried product to the outside. The collection unit 40 also plays a role similar to that of the transportation unit 41 because the transportation unit 42 is also provided inside the collection unit 40. The transporting device 42 may use a known means such as a piston instead of the screw. It is preferable that the transport speed at the time of transporting the dehydrated product or the dried product by the transport device 42 is at least an arbitrary speed such that the dehydrated product or the dried product is not excessively accumulated inside the collection unit 40. The measuring unit 44 is configured to measure the water content of the organic waste W by microwaves. The organic waste W after the measurement is returned to the inside of the pipe 30 through a return unit (not shown).

  Conventionally, one measurement time (time from sampling to obtaining a measurement result) is long. Therefore, there is a problem that the feedback control and the like cannot be performed in real time. In other words, it often took about half a day to one day from obtaining the organic waste W to obtaining the measurement result. Therefore, the content of the control is appropriate for the operating condition one hour before, and cannot be said to be appropriate for the operating condition of the device 35 at the present time. In addition, even with a general moisture meter (infrared type or halogen type), it took about 30 minutes to 1 hour to obtain a measurement result.

  Therefore, by using a microwave as in the present invention, the time from sampling to execution of the control can be shortened (about 1 minute to 15 minutes), so that occurrence of the time lag as described above can be prevented. it can. In addition, when measuring the moisture content of a dried material, it can be similarly set to about 1 minute to 15 minutes.

  Further, a series of operations of collecting, consolidating, and measuring the organic waste W may be continuously performed. That is, the organic waste W is continuously collected, not intermittently, and the collected organic waste W is continuously compacted and continuously measured, whereby the water content of the organic waste W is reduced. The change can be known in real time. As a result, the dehydrating conditions and drying conditions of the dehydrator 3 and the dryer 5 can be quickly changed according to the change.

  The measuring device N measures moisture by the speed of microwaves (electromagnetic waves), and its transmission speed is greatly affected by the dielectric constant of air and objects. Therefore, before the microwave measurement, the organic waste W is compacted (by pressing or the like) so that the degree of influence of air is always kept at the same level.

  In addition, regarding the collection of the organic waste W, the stored organic waste W may be collected, but it is more preferable to collect the moving organic waste W. For example, even if the water content of the organic waste W stored in the container 15 is measured, the dehydrator 3 and the dryer 5 are operated so as to be in an appropriate operation state, that is, operated so as to have a target water content. I do not know if it is. Therefore, for example, a measuring device N is provided at the position of N1 or N4 in FIG. 1 and the moving organic waste W is collected and measured. It is good to know if it is.

  Further, the sampling unit 40 of the measuring device N is inserted into a tube provided in, for example, N1, N2, N4, N5, or the like. The moving speed of the dehydrated or dried material moving inside the tube is generally in the range of 0.5 m / s to 150 m / s. Further, in FIG. 2, the sampling unit 40 is inserted toward the center of the tube 30, but may be inserted slightly off the center.

  The insertion area D2 of the sampling unit 40 with respect to the cross-sectional area D1 of the pipe (refers to the cross-sectional area in the pipe; the same applies hereinafter) is preferably 0.05% to 5%, more preferably 1% to 5%. If the insertion area D2 of the collection unit 40 is smaller than 0.05%, the amount of dehydrated or dried matter collected is small, and measurement cannot be started until a predetermined amount of dehydrated or dried matter is deposited. However, there is a problem that it is difficult to detect the water content in real time. In addition, when the insertion area of the sampling unit 40 is larger than 5%, the amount of dehydrated or dried matter is increased, and there is a problem that the dehydrated or dried matter is likely to be clogged inside the measuring device N. .

  As shown in FIG. 3, the sampling unit 40 has a shape in which, for example, a pipe extends in the horizontal direction, only the upper part of the pipe is cut in the horizontal direction, and an opening 45 that opens upward is provided. good. In FIG. 3, the opening 45 is hatched for convenience of description, but the hatched portion is usually hollow. With such a shape, dehydrated or dried matter falling from above due to gravity can be received from the opening 45 into the collection unit 40. Preferably, as shown in FIG. 3, it is preferable to provide the opening 45 over the entirety of the sampling unit 40. In this case, the insertion area of the sampling unit 40 indicates the total area of the opening 45.

  The area of the opening 45 with respect to the cross-sectional area D1 of the pipe (refers to the cross-sectional area inside the pipe; the same applies hereinafter) is preferably 0.05% to 5%, more preferably 1% to 5%. If the insertion area of the opening 45 is smaller than 0.05%, the amount of dehydrated or dried matter collected is small, and measurement cannot be started until a predetermined amount of dehydrated or dried matter is deposited. There is a problem that it is difficult to detect the water content in real time. Further, if the insertion area of the opening 45 is larger than 5%, the amount of dehydrated or dried matter collected is increased, and there is a problem that the dehydrated or dried matter is likely to be clogged inside the measuring device N. .

  Further, the length L2 for inserting the sampling unit 40 with respect to the inner diameter L1 of the tube is preferably set to 60% or more, more preferably 80% or more. If the insertion length L2 of the sampling unit 40 is less than 60%, the amount of dehydrated or dried matter collected is small, and measurement cannot be started until a predetermined amount of dehydrated or dried matter is deposited. Therefore, there is a problem that it is difficult to detect the water content of the dehydrated product or the dried product in real time. The inner diameter L1 of the tube is more preferably set to 50 mm or more.

(Control details)
The reason for providing the measuring device N is to monitor the water content of the dehydrated product and the dried product. When the water content is not within the desired range, control for changing the dehydration conditions and the drying conditions may be performed. For example, a measuring device N may be provided at a downstream position (for example, N1) of the continuous hot-air dryer 5, and the operation of the dryer 5 may be controlled based on the measurement result (feedback control). In this case, it is better to measure after the organic waste W is discharged from the solid-gas separator 6 than to measure before the organic waste W is supplied to the solid-gas separator 6. This is because before being supplied to the solid-gas separator 6, the organic waste W moves at a high speed in a flow path (for example, a pipe), and its collection is difficult.

  Among the continuous hot-air dryers 5, a tubular-type flash dryer 5CF is suitable as the dryer 5 according to the present invention. This is because, in the tubular-type flash dryer 5CF, since the time during which the organic waste W stays in the dryer 5CF is short, the time required for one cycle of collection, consolidation, measurement, and control can be reduced. This is because the adjustment of the operation of the dryer 5CF can be promptly changed.

  In addition, although various control methods of the continuous hot-air dryer 5 can be considered, a change in the temperature of the hot air used in the continuous hot-air dryer 5 can be exemplified. For example, the temperature of the hot air is changed to an arbitrary temperature in a range of about 250 ° C. to 500 ° C., and the organic waste W is dried to a target moisture content.

  Further, a measuring device N may be provided at a downstream position (for example, N4 or N5) of the dehydrator 3, and the operation of the dehydrator 3 may be controlled based on the measurement result. The control of the dehydrator 3 includes, for example, in the case of the in-machine two-liquid refining type centrifugal dehydrator 3, a change in the injection amount of the polymer flocculant HC or the inorganic flocculant IC, and a change in the number of rotations of the rotary bowl. Can be mentioned. When the dewatering machine 3 is a centrifugal dewatering machine or a belt press dewatering machine, changes in centrifugal force, differential speed, tension of the filter cloth, running speed of the filter cloth, stirring speed of the coagulation mixing tank, and the like are given. be able to.

  As described above, according to the method and apparatus 1 for treating organic waste W according to the present invention, the water content of the organic waste W discharged from the dehydrator 3 and the dryer 5 is set to a value close to the target value. Can be changed. As a result, the value of the organic waste W as a fuel resource or the like can be increased.

  Further, by controlling the amount of the organic waste W supplied to the dehydrator 3 and the amount of the coagulant used for dehydration to be increased or decreased, the water content of the dehydrated product can be made uniform. When the moisture content of the dehydrated product becomes uniform, there is an advantage that operation control in a subsequent step (for example, a drying step) becomes easy. In addition, when the processing capacity of the dewatering machine 3 has a surplus, by increasing the supply amount of the organic waste W, the dewatering processing amount per unit time can be increased. Conversely, when the organic waste W exceeding the processing capacity of the dewatering machine 3 is supplied, the load on the dewatering machine 3 can be reduced by reducing the supply amount of the organic waste W. The product life of the machine 3 can be extended. In addition, by optimizing the amount of the coagulant used for dehydration, the addition of an extra coagulant can be prevented, so that the running cost can be suppressed.

  Further, when the moisture content of the dried matter discharged from the dryer 5 is measured by the measuring device N and the amount of hot air and the temperature of the hot air used for the dryer 5 are controlled based on the measured value, the amount of hot air By optimizing the temperature of the hot air and the temperature of the hot air, waste of the auxiliary fuel used for the hot air generator 4 can be suppressed. In addition, by quickly changing the drying conditions based on the measured moisture content, the moisture content of the dried product can be made uniform. For example, when the dried product is used as a fuel resource, the product value is increased. Can be.

  Although FIG. 1 illustrates the processing apparatus 1 including both the dehydrator 3 and the dryer 5, the present invention is not limited to such a form, and any one of the dehydrator 3 and the dryer 5 may be used. The processing apparatus 1 having only one of them may be used. In this case, the measuring device N may be provided downstream of one of the dehydrator 3 and the dryer 5. Then, one of the dehydrator 3 and the dryer 5 may be controlled based on the water content measured by the measuring device N.

1: Treatment device, 2: Sludge storage tank, 3: Dehydrator, 4: Hot air generator, 5: Continuous hot air dryer, 5a to 5d: Pipe, 5F: Flash dryer, 5CF: Circular tubular dryer , 5X: supply port, 5Y: discharge port, 6: solid-gas separator, 7: dehydrated product transporter, 8: particle size distribution measuring device, 9: powder / particle upstream transport, 10: powder / particle downstream transport, 11: venturi scrubber, 12: exhaust fan, 13: mist separator, 14: plasma deodorizer, 15: container, 17: air compressor, 18: storage tank, 19: rotary valve, 20: digestion tank, 21: supply pump Reference numerals 31 to 33: tube, 40: sampling unit, 41: transport unit, 42: transport equipment (screw, piston, etc.), 43: consolidation unit, 44: measuring unit, 45: opening, E: atmosphere, F: fuel , M: motor, N: (moisture content) measuring device , N1~N7: an example of the installation location of the measurement device, W: sludge

Claims (8)

  It has a measuring step of continuously performing a series of operations of continuously collecting dehydrated organic waste discharged from an outlet of a dehydrator, consolidating, and measuring a water content by a microwave. Organic waste treatment method.   Having a measuring step of continuously performing a series of operations of continuously collecting dried matter of the organic waste discharged from the outlet of the dryer and measuring the water content by microwave after consolidation. Organic waste treatment method. Collection of the dehydrated product,
2. The method for treating organic waste according to claim 1, wherein a part of the dehydrated product is extracted while moving through a flow path connected to the dehydrator. Collection of the dried product,
3. The method for treating organic waste according to claim 2, wherein the drying is performed by extracting a part of the dried product while moving in a flow path connected to the dryer. An organic waste treatment device having a measurement device for measuring the water content of dehydrated organic waste,
The measuring device comprises:
A collecting unit for continuously collecting the dehydrated product,
A consolidation unit for consolidating the collected dehydrated product,
An apparatus for treating organic waste, comprising a measuring unit for measuring the moisture content of the compacted dehydrated product by microwaves. An organic waste treatment device having a measuring device for measuring the water content of dried organic waste,
The measuring device comprises:
A collecting unit for continuously collecting the dried product,
A consolidation unit for consolidating the collected dried product,
An organic waste treatment apparatus, comprising: a measuring unit for measuring the moisture content of the compacted dried product by microwave. The organic waste treatment device has a pipe connected to an outlet of the dehydrator,
The sampling unit of the measuring device is inserted inside the tube,
A moving speed of the dehydrated material moving inside the tube is in a range of 0.5 m / s to 150 m / s;
The organic waste treatment apparatus according to claim 5, wherein a length of inserting the collection unit with respect to an inner diameter of the pipe is 60% or more. The organic waste treatment device has a pipe connected to an outlet of the dryer,
The sampling unit of the measuring device is inserted inside the tube,
A moving speed of the dried material moving inside the tube is in a range of 0.5 m / s to 150 m / s;
7. The organic waste treatment apparatus according to claim 6, wherein a length of inserting the sampling unit with respect to an inner diameter of the pipe is 60% or more.

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