JP2002011499A - Sludge drying equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sludge drying device capable of performing a reliable sludge drying operation by judging beforehand changes in sludge properties, heat transfer efficiency of a sludge dryer, performance deterioration of a sludge supply pump, and the like. . SOLUTION: A sludge drying device includes a heat transfer cylinder 2a into which sludge from a sludge supply pump 1 is supplied, and a main shaft 1 in the heat transfer cylinder 2a.
0 and a jacket 9 provided outside the heat transfer drum 2a to form a vapor space 9a between the heat transfer drum 2a and the heat transfer drum 2a.
The steam supplied into the jacket 9 from the steam inlet 23 is
The water is condensed in the jacket 9 to be drained and discharged from the drain outlet 24. The drain outlet 24 is provided with the drain flow meter 14, and the control device 7 controls the motor 25 for the main shaft 10 and the sludge supply pump 1 based on a signal from the drain flow meter 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a water purification plant, a sewage treatment plant,
The present invention relates to a sludge drying device that uses steam as a heating source to remove water from sludge in order to reduce or recycle sludge discharged from a factory wastewater treatment facility or the like.

[0002]

2. Description of the Related Art A conventional sludge drying apparatus will be described with reference to FIG.

As shown in FIG. 7, the sludge drying apparatus includes a sludge dryer 2 and a sludge supply pump 1 for supplying sludge to the sludge dryer 2, and the sludge from a sludge storage tank of a water treatment facility is supplied with sludge. It is supplied to the sludge dryer 2 by the pump 1. The sludge supplied to the sludge dryer 2 is indirectly heat-exchanged with the heating steam generated in the boiler 3 to evaporate the water held by the sludge to form a low-moisture content dried sludge. It is discharged from the dryer 2. The heating steam that has undergone heat exchange in the sludge dryer 2 is condensed into heating water, discharged as drain from the sludge dryer 2, and heated steam is newly supplied into the sludge dryer 2.

[0004] Gas generated from the sludge in the sludge dryer 2 and vaporized vapor containing fine dust are sucked by the exhaust gas fan 4. Thereafter, the evaporated vapor is condensed by the cooling water in the exhaust gas treatment device 5 and then discharged, and the water-insoluble gas is decomposed by the deodorizing device 6.

[0005] The control device 7 is a component of the sludge drying device,
For example, the operation of the sludge supply pump 1 and the sludge dryer 2 is controlled. In the sludge dryer 2, a main shaft driven by a motor 25 via a V-belt 26 is rotatably arranged.

[0006]

In order for the moisture content of the dried sludge discharged from the sludge dryer 2 to be stable, the amount of the sludge supplied to the sludge dryer 2 is stabilized and the sludge dryer 2 It is necessary for stable heat exchange between the sludge and the heating steam to be performed in the inside.

However, sludge having poor water evaporation properties,
When the heat exchange efficiency in the sludge dryer 2 changes due to an adverse effect of the sludge properties or a decrease in the heat transfer efficiency of the sludge dryer 2, the moisture content of the dried sludge discharged from the sludge dryer 2 increases. Further, when the sludge amount actually supplied to the sludge dryer 2 becomes lower than the set value due to the performance deterioration of the sludge supply pump 1, the sludge cannot be processed as planned. On the other hand, if the components of the sludge supply pump 1 are replaced on the stable side in order to prevent the performance of the sludge supply pump 1 from deteriorating, maintenance costs will increase.

The conventional sludge drying apparatus does not have a function of reliably detecting a change in sludge properties, a decrease in the heat transfer efficiency of the sludge dryer 2 and a decrease in the performance of the sludge supply pump 1, so that a good sludge treatment operation is maintained. In fact, it is difficult to reduce maintenance costs.

The present invention has been made in view of the above points, and it has been found that sludge properties change, the heat transfer efficiency of the dryer decreases, and the like.
It is an object of the present invention to provide a sludge drying device capable of reliably determining a decrease in performance of a sludge supply pump.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a heat transfer cylinder into which sludge supplied by a sludge supply device is introduced, and a rotatably disposed heat transfer cylinder in the heat transfer cylinder, which is driven by a driving device. A main shaft having a blade on an outer periphery thereof, a jacket provided outside the heat transfer drum and forming a steam space between the heat transfer drum and a jacket having a steam inlet and a drain outlet, and a drain outlet is provided at the drain outlet. The sludge drying device is characterized in that a drain meter for measuring the flow rate is installed, and a driving device for the main shaft is controlled by a control device based on a signal from the drain meter.

The present invention is a sludge drying apparatus characterized in that the control device further controls the sludge supply device based on a signal from the drain meter.

The present invention is a sludge drying apparatus characterized in that the drain meter comprises a drain flow meter for measuring a drain flow rate.

According to the present invention, there is provided a sludge drying apparatus characterized in that the drain meter comprises a drain water level meter for measuring the water level of the temporarily stored drain.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIGS. 1 to 4 are views showing a first embodiment of a sludge drying apparatus according to the present invention.

1 to 4, the sludge drying apparatus includes a centrifugal thin film type sludge dryer 2 and a sludge supply pump (sludge supply device) 1 for supplying sludge into the sludge dryer 2.

The sludge dryer 2 includes a heat transfer drum 2a having a sludge inlet 21 and a sludge discharge outlet 22, a main shaft 10 rotatably disposed in the heat transfer drum 2a and having a plurality of blades 12 on its outer periphery. , The heat transfer drum 2a disposed outside the heat transfer drum 2a
And a jacket 9 that forms a steam space 9a between them. The main shaft 10 is driven by a motor (drive device) 25 via a V-belt 26, and a distribution ring 11 is mounted on the upper portion of the main shaft 10. Further, the jacket 9 is provided with a steam inlet 23 through which steam flows, and a steam space 9 is provided.
The vapor in a is condensed and becomes drain, and the drain outlet 24
Is discharged from

A drain flow meter 14 is connected to the drain outlet 24 via a steam trap 13, and a signal from the drain flow meter 14 is sent to the control device 7. Control device 7
Controls an inverter 15 for controlling the number of revolutions of the motor 25 to control the drive by controlling the number of revolutions of the motor 25 and an inverter 16 for setting the flow rate of the sludge feed pump 1 to control the drive.

The sludge supplied from the sludge supply pump 1 into the heat transfer cylinder 2a through the sludge inlet 21 adheres to the distribution ring 11 of the main shaft 10 rotating inside the heat transfer cylinder 2a, and then acts on the centrifuge. The particles are scattered from the distribution ring 11 by the force and adhere to the inner surface of the heat transfer drum 2a. As shown in FIG. 3, the sludge attached to the inner surface of the heat transfer drum 2a is scraped off by a blade 12 attached to the main shaft 10 to form a thin film.
The sludge in the heat transfer drum 2a undergoes heat exchange with the heating steam supplied from the steam inlet 23 to the steam space 9a between the heat transfer drum 2a and the jacket 9, and the retained moisture evaporates to reduce the water content. descend. The steam supplied to the steam inlet 23 is generated by the boiler 3. The sludge flows down the inner surface of the heat transfer drum 2a by the action of gravity, and the water gradually evaporates to reach a target moisture content, and is discharged from the lower sludge drainage port 22.

The heated steam supplied from the steam inlet 23 to the steam space 9a in the jacket 9 is condensed by exchanging heat with the sludge to become drain (heated water), and is discharged from the drain outlet 24. Drain then steam trap 13
Through the drain flow meter 14 downstream of the steam trap 13
And the drain flow rate of the condensed heated water is measured by the drain flow meter 14.

During this time, the control device 7 controls the rotation speed control inverter 15 for the main shaft 10 and the flow rate setting inverter 16 for the sludge supply pump 1 based on a signal from the drain flow meter 14. Further, the gas of the heat transfer drum 2a is sucked from the gas outlet 28 as exhaust gas by the exhaust gas fan 4 and discharged outside through the exhaust gas treatment device 5 and the deodorization device 6.

Next, the operation control in the control device 7 will be described with reference to FIG. Figure 4 As shown in, in the normal drying operation, the drain outlet 24 of the sludge from the feed pump 1 and the water content C _K of the feed sludge supplied, drain flow S jacket 9 commensurate with the supplied sludge flow rate F _K Is discharged from

The feed sludge flow rate when the F _K, drain flow S using the moisture content C _D of the dry sludge discharged from the sludge discharge opening 22 of the heat transfer cylinder is calculated by the equation (1).

[0023] _{S = F K (C K -C} D) / (1-C D) (1) drain flow S is governed by variations in the moisture content _{C D} of the dry sludge and water content _{C K} of the feed sludge Therefore, for example, the allowable amount of drainage _{S a} and 1.0 to 1.5 times the calculated value of the formula (1).

Therefore, the drain flow is measured by the drain flow meter 14.
The quantity S is measured and the measured value S_MIs the allowable drain flow rate S_AExample
If it is within the range, the control device 7 determines that the operation is normal. Measurement
Value S _MIs the allowable drain flow rate S_AAnd the permissible drain flow rate S
_AIn the following cases, the control device 7 changes the sludge properties and
That the heat transfer efficiency of the sludge dryer 2 has decreased
And the rotation speed R of the main shaft 10 of the sludge dryer 2_DRaise and dry
Improve performance.

The limit value R of the rotation speed of the main shaft 10_DLRotate up
Even if the number is increased, the measured value S of the drain flow rate _MIs the allowable value S_Arange
If it does not fit inside, the control device 7 controls the sludge supply pump 1
Of the sludge feed pump 1_PRaise
To secure supply. Limit value R of rotation speed_PLSludge up
The measured value S of the drain flow rate even when the rotation speed of the supply pump 1 is increased
_MIs the allowable value S_AIf it does not fit within the range,
Judging that the service life of the pump 1 has expired, the operation of the sludge dryer 2 is stopped.
You.

As described above, according to the present embodiment, by measuring the drain flow rate by the drain flow meter 14, the change of the sludge property, the heat transfer efficiency of the sludge dryer 2, and the performance of the sludge supply pump 1 are performed. A decrease can be determined. Therefore, maintenance costs can be reduced by extending the replacement cycle of parts, and good drying processing can be maintained.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS.

In the second embodiment shown in FIGS. 5 and 6, a drain tank 17 for temporarily storing drain and a water level gauge 17a installed in the drain tank 17 are provided instead of the drain flow meter 14. The other parts are substantially the same as those of the first embodiment shown in FIGS.

[0029] In FIGS. 5 and 7, to set the permissible water level _{L A} commensurate with allowable drain flow _{S A,} water level gauge 1
The controller 7 if the measured water level L _M allowable water level L _A range 7a judges that the normal operation. On the other hand, the measurement water level L _{when M} water out of the allowable water level L _A is decreased, it is determined that changes and heat transfer efficiency decreases sludge dryer 2 of sludge characteristics is occurring, the main shaft 1 of the sludge drier 2
The drying performance is improved by increasing the rotation speed _{RD of} 0. Spindle 1
The rotational speed of 0 if even increasing the rotation speed to the limit value R _DL measurement level L _M does not fall within the allowable value L _A range, the control unit 7 determines that the degradation of the sludge supply pump 1, the sludge supply pump Assurance of supply amount by increasing the first rotational speed R _P. Even if the rotation speed of the sludge pump 1 is increased to the limit value _{RPL, the} measured water level L
_M may not fall within the allowable value L _A range, it determines that the life of the sludge supply pump 1, to stop the operation of the sludge drier 2.

As described above, according to the present embodiment, it is also possible to determine a change in sludge properties, a heat transfer efficiency of the sludge dryer 2, and a decrease in performance of the sludge supply pump. Therefore, maintenance costs can be reduced by extending the replacement cycle of parts, and good drying processing can be maintained.

[0031]

As described above, according to the present invention, a change in sludge properties, a heat transfer efficiency of a dryer and a decrease in performance of a sludge supply pump can be reliably determined. Therefore, maintenance costs can be reduced by extending the replacement cycle of parts, and good drying processing can be maintained.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a sludge drying apparatus according to the present invention.

FIG. 2 is a configuration diagram showing details of a centrifugal thin film type sludge dryer.

FIG. 3 is an explanatory view showing a function of a blade of the centrifugal thin film type sludge dryer.

FIG. 4 is a flowchart illustrating the operation of the sludge drying device according to the present invention.

FIG. 5 is a configuration diagram showing a second embodiment of the sludge treatment apparatus according to the present invention.

FIG. 6 is a flowchart illustrating the operation of the sludge drying device according to the present invention.

FIG. 7 is a configuration diagram showing a conventional sludge drying device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sludge supply pump 2 Sludge dryer 2a Heat transfer cylinder 4 Exhaust gas fan 5 Exhaust gas treatment device 6 Deodorizing device 7 Control device 9 Jacket 9a Steam space 10 Main shaft 11 Distribution ring 12 Blade 13 Steam trap 14 Drain flow meter 15 Inverter for rotation speed control 16 Flow rate setting inverter 17 Drain tank 17a Drain water level gauge 23 Steam inlet 24 Drain outlet 25 Motor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Katsu Ide 2-4, Suehirocho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture F-term in Toshiba Keihin Works (reference) 3L113 AA04 AB05 AC05 AC15 AC45 AC46 AC48 AC49 AC50 AC53 AC54 AC58 AC63 AC67 BA37 CA11 CB23 CB29 CB34 DA06 DA10 DA18 4D059 AA03 BD11 BD24 BD26 EA20 EB20

Claims (4)

[Claims] 1. A heat transfer drum into which sludge supplied by a sludge supply device is introduced, a main shaft rotatably disposed in the heat transfer drum, driven by a driving device, and having a blade on an outer periphery; Provided outside the heat transfer cylinder, forming a steam space between the heat transfer cylinder and the jacket having a steam inlet and a drain outlet, and installing a drain meter for measuring the drain amount at the drain outlet. A sludge drying apparatus characterized in that a driving device for a main shaft is controlled by a control device based on a signal from the drain meter. 2. The sludge drying device according to claim 1, wherein the control device further controls the sludge supply device based on a signal from the drain meter. 3. The sludge drying apparatus according to claim 1, wherein the drain meter comprises a drain flow meter for measuring a drain flow rate. 4. The sludge drying apparatus according to claim 1, wherein the drain meter comprises a drain water level meter for measuring the water level of the temporarily stored drain.