JP3674811B2 - Sludge introduction equipment for sludge treatment equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sludge introduction device of a sludge treatment facility, and more specifically, water-containing sludge such as sewage sludge which has not been subjected to pretreatment such as drying and additive addition, from the lower part of a preheater to a kiln bottom of a dry cement kiln for cement raw material firing. The present invention relates to a sludge introduction device for a sludge treatment facility that is introduced and burned up to a section.
[0002]
[Prior art]
Sewage sludge discharged from sewage treatment plants has been used as fertilizer since ancient times, but the reason is that heavy metals are contained in sludge and that the amount of treatment is small when used as fertilizer. In recent years, land reclamation and ocean dumping have become mainstream.
However, sludge discharge from sewage treatment plants has been increasing in recent years, mainly in the Tokyo metropolitan area, and due to the lack of treatment plants for land reclamation and disposal at sea, as well as restrictions on preventing environmental pollution, At present, sludge treatment has shifted to incineration. Several types of sludge incineration facilities have already been proposed.
[0003]
However, in a conventional sludge incinerator using an incinerator, it is necessary to dry the sludge prior to incineration. In addition, the deodorized dry exhaust gas must be deodorized. Thereby, there existed a problem that drying cost, deodorizing cost, and incineration cost increased, and the processing cost as a whole became high.
A method using quick lime for drying sludge has also been proposed. In this method, quick lime is reacted with moisture contained in sludge to produce slaked lime, the residual moisture is evaporated by the reaction heat at that time, and the sludge is utilized as a dry material that can be pneumatically fed as a cement raw material. However, even this method has a problem that quick lime must be added during sludge drying.
[0004]
Therefore, as a prior art for solving such a problem, there is known a “sludge treatment method” disclosed in Japanese Patent Application Laid-Open No. 8-276199, which was previously filed by the applicant of the present patent application.
This is a sludge treatment technology in which water-containing sludge in a sludge tank is directly introduced into a kiln bottom or a preheater of a dry cement kiln and incinerated. According to this technology, water-containing sludge is poured directly into an existing dry cement kiln by a pump without performing any pretreatment to dry or add additives, and at the same time as normal production of cement clinker, It is possible to incinerate water-containing sludge.
[0005]
[Problems to be solved by the invention]
By the way, in this prior art, the water-containing sludge in the storage tank is thus fed into the kiln bottom of the dry cement kiln or the preheater by, for example, about 10% of the amount of cement clinker produced by the pump. Since it was just poured, the introduced water-containing sludge often became sludge-like lump.
As a result, the calcination efficiency of the water-containing sludge is poor, it takes a relatively long time to sufficiently burn the water-containing sludge, and it is easy to produce massive combustion ash, which is also useful as a cement component for the cement clinker in the kiln. There is a problem that the combustion ash cannot be evenly dispersed.
[0006]
OBJECT OF THE INVENTION
It is an object of the present invention to provide a sludge introduction device for a sludge treatment facility that can increase the combustion efficiency of hydrous sludge and can disperse the combustion ash of hydrous sludge relatively uniformly into cement clinker. It is said. Another object of the present invention is to provide a sludge introduction device for a sludge treatment facility that can prevent clogging of water-containing sludge in the sludge flow rate adjustment portion of the sludge introduction pipe.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 is a sludge for sludge treatment equipment in which water-containing sludge is introduced by a sludge introduction pipe between a lower part of a preheater for cement raw material calcining and a kiln bottom of a dry cement kiln for cement raw material firing. The sludge introduction pipe is a pipe material in which the sludge introduction pipe branches into a plurality of branch pipe sections in the middle of the pipe, and this sludge introduction pipe is bent upward in the middle of the pipe to hydrate the sludge into the upper part of the kiln bottom. The branch pipe part to be introduced and the branch pipe part that is bent downward and introduces the water-containing sludge into the lower part of the kiln bottom part are branched, and the opening area of the lower branch pipe part is the upper branch pipe. The sludge treatment facility is provided with a flow rate adjusting means for adjusting the flow rate ratio of the water-containing sludge flowing out from each branch pipe section in the lower branch pipe section of this sludge introduction pipe, which is slightly larger than the opening area of the sludge section Sludge introduction device .
Examples of the water-containing sludge here include sewage sludge, activated sludge, and sludge.
Hydrous sludge may be supplied directly from a sludge treatment facility via a pipeline, etc., or transported by a truck equipped with a sealed tank, and once supplied to the sludge tank, it may be supplied from this sludge tank. .
[0008]
Although there is no restriction | limiting in particular in the addition amount of the water-containing sludge to a dry kiln, Usually, it determines suitably by various process conditions, such as the quality of a cement raw material, the usage-amount, and a calcination temperature. However, an amount that allows the water-containing sludge to be introduced into an existing dry kiln without particularly changing the operating conditions is preferable.
For example, when a dry kiln with a cement clinker production amount of 90 to 100 t / h is used, the amount of water-containing sludge added is 9 to 10.0 t / h, which is about 1/10 or less of the weight of the cement clinker produced. It is preferable to add water-containing sludge. This is because if the amount of hydrous sludge added to the cement raw material exceeds 10.0 t / h, firing in the kiln becomes unstable due to moisture from the sludge, and the risk of adversely affecting the quality of the cement clinker increases.
[0009]
In addition, the space from the lower part of the preheater for cement raw material calcining to the kiln bottom of the dry cement kiln for cement raw material firing (hereinafter sometimes referred to as the kiln kiln bottom side) is the lower area of the preheater. It is not limited to the kiln bottom area of the dry kiln, but may be a connecting part of both. In addition, you may introduce | transduce a hydrous sludge into both the lower area | region of a preheater, and the kiln bottom part area of a dry kiln. Also, hydrated sludge is introduced into the upper and lower areas of the kiln bottom of the dry kiln . In this case, the water-containing sludge in the sludge introduction pipe is difficult to flow into the upper branch pipe part due to its own weight, but the water-containing sludge easily flows into the lower branch pipe part. A flow rate adjusting means for adjustment is provided.
In addition, you may introduce | transduce a hydrous sludge from two places in the lower area of a preheater, or the kiln bottom part area of a dry kiln. In this case, the weight of the hydrous sludge flowing through the sludge introduction pipe is equally applied to the left and right branch pipe sections. Thereby, it is preferable to arrange | position a flow ratio adjustment means (for example, needle valve) to a right and left branch pipe part.
[0010]
In addition, the temperature of the introduction part of the hydrous sludge in the kiln kiln bottom side is 800-1000 degreeC, Preferably it is around 900 degreeC. If it is less than 800 degreeC, combustion of a water-containing sludge tends to become inadequate. Moreover, when it exceeds 1000 degreeC, the malfunction which will interfere with furnace operation will arise.
As a method for introducing the hydrous sludge into the kiln kiln bottom side, for example, a method using a pipe pumping structure having various pumps such as a sludge pump can be cited. In addition, for example, a method using various conveyors such as a belt conveyor and a screw conveyor may be used. In short, any apparatus may be used as long as the water-containing sludge can be smoothly transferred.
The number of branch pipes in the sludge introduction pipe may be a predetermined number of two or more . Moreover, the location of the kiln kiln bottom side where each branch pipe part of a sludge introduction pipe | tube is connected is not limited. And the apparatus used for the flow volume adjustment of hydrous sludge may be any apparatus.
[0011]
The flow rate ratio adjusting means here is not limited as long as it is a structure that can adjust the flow rate ratio of the water-containing sludge divided into the branch pipe portions. For example, in addition to the needle valve of claim 3, valve structures such as a rotary valve, a gate valve, a butterfly valve, and a double leaf valve can be mentioned. However, since water-containing sludge such as sewage sludge contains a relatively large amount of fibers and hair that are entangled with the valve body, a needle valve that is less likely to entangle this fiber and hair or a similar valve is preferable. The flow rate ratio adjusting means may be a manual type by an operator or an automatic type having a drive unit such as an electric motor.
[0012]
A second aspect of the present invention is the sludge dispersion introducing apparatus according to the first aspect, wherein the flow rate ratio adjusting means is a needle valve.
The needle valve may be provided in each of the plurality of branch pipe portions, or may be provided only in one branch pipe portion in the case of two branch pipe portions, for example.
[0013]
[Action]
According to claims 1 to 2 in serial mounting of the invention, a plurality of locations between the lower part of the preheater to the kiln inlet part of the dry cement kiln, dividing the water sludge from the corresponding branch pipe portion of the sludge inlet pipe Inflow. As a result, the dispersibility of the water-containing sludge in the dry cement kiln in which the cement raw material is fired is improved. Thereby, the combustion efficiency of hydrous sludge increases and the time until hydrous sludge burns is shortened. Further, it is difficult to form a massive combustion ash after combustion. As a result, the combustion ash can be dispersed relatively evenly in the cement clinker in the kiln.
[0014]
In particular, according to the first aspect of the present invention, at the time of introducing the water-containing sludge to the kiln kiln bottom side, the ratio of the water-containing sludge flowing out from each branch pipe portion of the sludge introduction pipe is adjusted by the flow rate adjusting means. Therefore, in accordance with the distribution of the furnace temperature, the amount of water-containing sludge that can be incinerated can be appropriately distributed to each sludge introduction portion on the kiln kiln bottom side. Thereby, the combustion efficiency of the water-containing sludge to a dry-type cement kiln further increases.
[0015]
Further, according to the serial mounting of the invention in claim 2, the flow rate ratio adjustment means is a needle valve, the fibers in the water-containing sludge, even like hair contains a large amount, which is the like entangled in the valve body The risk of inconvenience in adjusting the flow rate of hydrous sludge is reduced.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional view of a cement firing facility to which a sludge introduction device for a sludge treatment facility according to an embodiment of the present invention is applied. FIG. 2 is an enlarged cross-sectional view showing the periphery of the branch pipe portion of the sludge introduction pipe.
In FIG. 1, reference numeral 10 denotes a sludge introduction device (hereinafter simply referred to as a sludge introduction device) of a sludge treatment facility. This sludge introduction device 10 is provided in a cement firing facility of a cement manufacturing plant so that the cement raw material is fired. Water-containing sludge (here, sewage sludge) a that is incinerated using the heat of is supplied to this calcination facility.
The cement firing facility is a facility for intermediately producing a cement clinker by firing a cement raw material calcined in the preheater 11 in a dry cement kiln 12. In addition, the dry-type cement kiln 12 used here shall produce a cement clinker at 90-100 t / h.
[0017]
The preheater 11 preheats cement raw material pulverized by a raw material mill (not shown) to a predetermined temperature so that it can be easily fired by a downstream dry cement kiln 12. The preheater 11 is provided with a large number of cyclones mounted on a several-storey steel frame. Further, normally, a gas exhaust system that has a fan and guides the gas generated at the time of calcination to a gas processing facility (not shown) is connected to the uppermost cyclone.
[0018]
The dry cement kiln 12 has a horizontal cylindrical kiln shell slightly inclined downward toward the downstream side. A refractory material is stretched on the inner peripheral surface of the kiln shell.
While rotating this kiln shell in the circumferential direction, heavy oil or fine coal is used as a fuel and heated by a burner, whereby the cement raw material from the preheater 11 is fired to produce a cement clinker in the middle. Thereafter, the cement clinker is cooled by a clinker cooler connected to the downstream portion of the dry cement kiln 12 and sent to the finishing process.
[0019]
Next, the sludge introduction device 10 will be described in detail with reference to FIGS. 1 and 2.
As shown in FIG. 1, the sludge introduction apparatus 10 keeps the water-containing sludge such as the settled sludge from the sewage treatment plant in a slurry state from the lower part of the preheater 11 to the kiln bottom part 12a of the dry cement kiln 12 (kiln kiln bottom). Directly) in a dispersed state and incinerated. More specifically, the hydrated sludge from the externally installed sludge receiving facility is temporarily stored in the sludge tank 14 by the pressure feed pump 13, and then dried from the sludge tank 14 through the sludge introduction pipe 16 by the pressure feed pump 15 as needed. It is introduced into the kiln bottom 12a of the cement kiln 12.
[0020]
The sludge introduction pipe 16 is branched into a branch pipe part 16a bent upward in the middle of the pipe and a branch pipe part 16b bent downward. That is, the water-containing sludge flowing in the sludge introduction pipe 16 is divided into two in the middle of this pipe, one flows into the upper branch pipe section 16a and flows into the upper part of the kiln bottom section 12a, and the other flows into the lower branch pipe section 16b. To the bottom of the kiln bottom 12a. The opening area of the lower branch pipe portion 16b is slightly larger than the opening area of the upper branch pipe portion 16a.
A needle valve 17 which is an example of a flow rate adjusting means for adjusting the flow rate ratio of the hydrated sludge a flowing out from the branch pipe portions 16a and 16b is provided at the base portion of the lower branch pipe portion 16b having a large opening area. Yes. By rotating the valve shaft 19 connected to the rotation shaft of the servo motor 18, the tapered valve body 20 is advanced and retracted to adjust the flow rate of the water-containing sludge a. The needle valve 17 is provided only in the lower branch pipe portion 16b as described above. The water-containing sludge a in the sludge introduction pipe 16 is difficult to flow into the upper branch pipe portion 16a due to its own weight, but the lower branch pipe This is because the water-containing sludge a easily flows into the portion 16b.
[0021]
Next, a sludge introduction method for a sludge treatment facility using the sludge introduction apparatus 10 of this embodiment will be described.
As shown in FIG. 1, in the cement firing facility, the cement raw material is calcined while flowing down each cyclone of the preheater 11. Thereafter, the cement raw material flows into the kiln bottom 12a of the dry cement kiln 12 and is fired by the heat of the burner to become a cement clinker.
At this time, in the kiln bottom 12a of the dry cement kiln 12, the water-containing sludge a in the sludge tank 14 is introduced by the sludge introduction device 10 through the sludge introduction pipe 16 at a rate of 4 t / h. It is poured while being dispersed.
A specific introduction route of the hydrous sludge a into the kiln bottom portion 12a will be described. The hydrous sludge a is temporarily stored in the sludge tank 14 by using a pumping pump 13 from a sludge receiving facility (not shown). Thereafter, the pressure pump 15 connected to the lower portion of the sludge tank 14 flows from the sludge introduction pipe 16 to the kiln bottom 12a of the dry cement kiln 12 as needed.
[0022]
At this time, since the upper and lower branch pipe portions 16a and 16b are branched in the middle of the sludge introduction pipe 16, the water-containing sludge a can be divided and flown into the kiln kiln bottom side from two directions. . Thereby, the dispersibility of the water-containing sludge a to the dry cement kiln 12 during firing of the cement raw material is improved as compared with the case where the sludge introduction pipe that is not branched is used. That is, the dispersibility of the water-containing sludge a improves as the number of the branch pipe portions increases. As a result, the combustion efficiency of the hydrous sludge a increases, and the time until the hydrous sludge a burns is shortened. Further, it is difficult to form a massive combustion ash after combustion. Therefore, the combustion ash can be dispersed relatively evenly in the cement clinker in the dry cement kiln 12.
When the water-containing sludge a is introduced to the kiln kiln bottom side, the ratio of the water-containing sludge a flowing out from the branch pipe portions 16a and 16b of the sludge introduction pipe 16 is, for example, 1: 1 or 1: 1.5, Adjustment is performed by operating the needle valve 17. Thereby, according to the distribution of the furnace temperature, the amount of water-containing sludge a that can be incinerated can be appropriately distributed to each sludge introduction portion on the kiln kiln bottom side. As a result, the combustion efficiency of the hydrous sludge a to the dry cement kiln 12 is further increased.
[0023]
The water-containing sludge a thus introduced can be incinerated economically by the burner heat at the time of firing the cement raw material, even if the pretreatment such as deodorization, drying, and additive addition, which is expensive to the water-containing sludge a, is not performed in advance. it can.
Furthermore, the water-containing sludge a is dispersed almost uniformly in the kiln butt portion 12a and eventually in the dry cement kiln 12 by the inflow of the branch pipe portions 16a and 16b in a divided state. Therefore, the contact area between the water-containing sludge a and the exhaust gas generated in the dry cement kiln 12 is increased, and the combustion efficiency of the water-containing sludge a is increased. As a result, the time until the water-containing sludge a is burned is shortened, and it is difficult to form a lump of combustion ash after combustion, and the combustion ash of the water-containing sludge a is transferred to the cement clinker intermediately manufactured in the dry cement kiln 12. A high-quality cement clinker that can be dispersed relatively uniformly and has a stable composition component is obtained.
Further, in this embodiment, since the needle valve 17 is employed as the flow rate ratio adjusting means, even if the water-containing sludge a contains a large amount of hair, for example, it is entangled with the valve body 20 and the water-containing sludge a The risk of inconvenience in flow rate adjustment is reduced.
[0024]
Next, a sludge introduction method and apparatus for a sludge treatment facility according to another embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is an enlarged longitudinal sectional view showing the flow rate ratio adjusting means in the sludge introduction device of the sludge treatment facility according to another embodiment of the present invention. FIG. 4 is an enlarged cross-sectional view showing the flow rate ratio adjusting means.
As shown in FIGS. 3 and 4, the sludge introduction device 30 according to another embodiment branches the sludge introduction pipe 16 into two upper and lower branch pipe portions 16a and 16c in the middle of the pipe, An extraction / insertion type cylindrical valve structure 31, which is another example of the flow rate adjusting means, is provided in the branch pipe portion 16 c, and the sludge discharge side of the lower branch pipe portion 16 c is provided with water-containing sludge a This is an example in which a dispersion device 32 is provided.
[0025]
The cylindrical valve structure 31 has a cylinder pipe 33 connected to the kiln bottom part 12a and the lower branch pipe part 16c. A cylindrical insertion / removal valve 34 with both ends sealed for adjusting the flow rate of the water-containing sludge a in the lower branch pipe portion 16c is inserted into the cylinder pipe 33 so as to be removable. Has been.
A pair of flanges 33 a protrude from the outer end of the cylinder tube 33. A pair of slide guide rods 35 parallel to the axis of the cylinder tube 33 are fixed to the outside of each flange 33a in a cantilever state. Further, a pair of flanges 34 b are also provided on the outer end face of the insertion / removal valve 34. A pair of slide rings 37 that are loosely inserted into the corresponding slide guide rods 35 are disposed at both ends of each flange 34b.
The operator holds the handle 34 a of the insertion / removal valve 34 and pushes and pulls the handle 34 a, so that the insertion / removal valve 34 slides along the pair of slide guide rods 35 in the axial direction of the cylinder tube 33. Each flange 33 a has a completely sealed position of the flow path of the lower branch pipe portion 16 c by the insertion / removal valve 34 inserted into the cylinder pipe 33 by adjusting the head protrusion amount of the deployed bolt. A pair of flow path sealing position adjusters 38 for adjusting the above are disposed.
[0026]
Next, with reference to FIGS. 3 and 4, the dispersion device 32 for the hydrated sludge a will be described in detail.
As shown in FIGS. 3 and 4, the dispersing device 32 has an elongated inner tube 39 disposed so as to be able to be taken in and out of the lower portion of the cylinder tube 33 with the outer end portion protruding outward. The end of the inner tube 39 on the side of the kiln butt 12 a is disposed near the end of the cylinder tube 33 on the side of the kiln butt 12 a.
On the other hand, a central portion of a guide plate 41 having a pair of slide rings 40 that are loosely inserted into the slide guide rods 35 is attached to the outer end portion of the inner tube 39. An external compressed air supply device 42 is connected to a pipe end outside the inner pipe 39.
[0027]
When the operator grasps and pushes and pulls the end of the inner pipe 39, the inner pipe 39 slides along the slide guide rod 35 in the axial direction of the cylinder pipe 33, and thereby the kiln bottom part 12 a of the inner pipe 39. The pipe end position moves in the axial direction in the cylinder pipe 33.
As a result, the pipe end of the inner pipe 39 on the side of the kiln bottom 12a has a position where the water-containing sludge a can be most effectively dispersed, that is, the degree of sagging near the end of the cylinder pipe 33 due to the difference in water content. It arrange | positions in the position of several cm from the front-end | tip of the water-containing sludge a which changes. Thereafter, when compressed air from the compressed air supply device 42 is blown outward from the pipe end of the inner pipe 39, the hydrous sludge a that has reached the inside of the one end of the cylinder pipe 33 due to this air pressure is transferred to the kiln bottom part 12a. It spouts while being finely dispersed inside.
[0028]
Thus, because the pipe end of the inner pipe 39 is moved to the most effective dispersion position of the water-containing sludge a, according to the hardness of the water-containing sludge a in which the degree of sagging changes due to the difference in water content, The water-containing sludge a can be dispersed well. In addition, in this way, compressed air is blown from the inside of the radiation to the water-containing sludge a in the cylinder pipe 33 so that the water-containing sludge a is blown to the outside. Can do.
Other configurations, operations, and effects are the same as those in the above embodiment, and thus description thereof is omitted.
[0029]
【The invention's effect】
According to this invention, since the water-containing sludge is divided and introduced into a plurality of locations on the kiln kiln bottom side, the dispersibility of the water-containing sludge in the dry cement kiln is improved. Thereby, the combustion efficiency of hydrous sludge increases and the time until this hydrous sludge burns is shortened. Moreover, it becomes difficult to form massive combustion ash after combustion. As a result, the combustion ash can be dispersed relatively evenly in the cement clinker in the kiln.
[0030]
In particular, according to the first aspect of the present invention, the flow rate ratio of the hydrated sludge flowing out from each branch pipe portion of the sludge introduction pipe is adjusted by the flow rate adjusting means, so that it matches the distribution of the furnace temperature. Thus, it is possible to distribute an amount of water-containing sludge that can be incinerated satisfactorily to each sludge introduction portion on the kiln kiln bottom side. As a result, the combustion efficiency of the water-containing sludge into the dry cement kiln is further increased.
[0031]
Further, according to the invention of claim 2, since the needle valve is adopted as the flow rate ratio adjusting means, even if the water-containing sludge contains a large amount of hair or the like, it is entangled with the valve body, and the water-containing sludge This reduces the possibility of inconvenience in adjusting the flow rate.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing a cement firing facility to which a sludge introduction device for a sludge treatment facility according to an embodiment of the present invention is applied.
FIG. 2 is an enlarged cross-sectional view showing the vicinity of a branch pipe portion of a sludge introduction pipe according to one embodiment of the present invention.
FIG. 3 is an enlarged vertical sectional view showing a flow rate ratio adjusting means in a sludge introduction device of a sludge treatment facility according to another embodiment of the present invention.
FIG. 4 is an enlarged cross-sectional view showing a flow ratio adjusting means according to another embodiment of the present invention.
[Explanation of symbols]
10 Sludge introduction equipment for sludge treatment equipment,
11 Preheater,
12 Dry cement kiln,
12a Kiln bottom,
16 Sludge introduction pipe,
16a, 16b, 16c Branch pipe part,
17 Needle valve (flow rate adjusting means),
30 Sludge introduction device,
31 cylindrical valve structure,
33 cylinder pipe,
34 Removable valve
39 Inner pipe,
42 compressed air supply device,
a Hydrous sludge.

Claims (2)

A sludge introduction device for a sludge treatment facility that introduces hydrous sludge by a sludge introduction pipe between the lower part of the preheater for cement raw material calcining and the kiln bottom of a dry cement kiln for cement raw material firing,
The sludge introduction pipe is a pipe material branched into a plurality of branch pipe parts in the middle of the pipe,
This sludge introduction pipe has a branch pipe part that bends upward in the middle of the pipe and introduces hydrous sludge into the upper part of the kiln bottom part, and a branch pipe that bends downward and introduces the hydrous sludge into the lower part of the kiln bottom part The opening area of the lower branch pipe part is slightly larger than the opening area of the upper branch pipe part,
A sludge introduction device for a sludge treatment facility, in which a flow rate adjusting means for adjusting a flow rate ratio of hydrous sludge flowing out from each branch pipe portion is provided at a lower branch pipe portion of the sludge introduction pipe . The sludge dispersion introducing apparatus according to claim 1, wherein the flow rate ratio adjusting means is a needle valve.

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