JPS6137034B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a dehydration system in which an endless band-shaped filter cloth is provided in a rotating state from a gravity dehydration section to a forced dehydration section, and a device is provided for supplying a material to be processed to the gravity dehydration section. Regarding equipment.

In the above device, dewatering to the gravity dehydration part is insufficient due to poor agglomeration of the processed material supplied to the gravity dehydration part or clogging of the filter cloth, and the filter cloth is clogged. The fluidity of the cake sent to the forced dewatering section is high, and the cake protrudes from the sides of the filter cloth during the dewatering process in the forced dewatering section, reducing the solid content recovery efficiency and reducing dewatering performance. There was a problem with the decline.

In view of the above-mentioned points, it is an object of the present invention to prevent the cake from protruding from the lateral side of the filter cloth in the forced dewatering section, thereby improving the dewatering performance.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

A storage tank 1 that supplies and stores materials to be treated such as sludge,
A flocculation system is formed by connecting a pipe R ₁ with a pump 2 and a pipe R 2 to a coagulant storage tank 4 and a pipe R ₂ with a variable capacity pump 5. A agent mixing device 6 is provided, and the material to be treated and the flocculant from both devices 3 and 6 are supplied to a rotary mixer 7 for agglomeration and mixing, and the agglomerated mixture is supplied to a belt press type dehydrator 8. The dewatering device is designed to be incorporated into various water treatment systems for human waste, urban sewage, industrial wastewater, etc., and to dehydrate materials to be treated such as sludge generated therein.

The belt press type dehydrator 8 is provided with an endless belt-shaped first rotary filter cloth 9, and the material to be processed from the mixer 7 is supplied between the first filter cloth 9 and the case side wall and the partition wall 10. A gravity dewatering section 11 is formed in which the moisture is filtered by gravity, and the thickness of the cake fed out on the first rotary filter cloth 9 is filtered on the downstream side of the gravity dehydration section 11 in the rotational direction of the filter cloth. A cake thickness adjustment roll 12 is provided as an example of an adjustment tool for adjusting the cloth 9 in the longitudinal direction and the width direction, and the first
A second rotary filter cloth 13 is provided between the rotary filter cloth 9 and the cake, the thickness of which has been adjusted. A forced dehydration section 14 is formed with a shear dehydration zone C having a shape path, and as the first filter cloth 9 rotates from the gravity dehydration section 11 to the forced dehydration section 14, the object to be treated is dehydrated. It is structured as follows.

In the middle of the rotation of the first filter cloth 9 from the end of the forced dewatering section 14 to the beginning of the gravity dewatering section 11,
A filter cloth cleaning device 15 that acts on each of the front and back sides of the filter cloth,
15, and a filter cloth cleaning device 16 is provided at the middle of rotation of the second filter cloth 13 below the shear dehydration zone C, and both filter cloths 9 and 13 are cleaned by the device 1, respectively.
The structure is such that backwashing is carried out by jetting and supplying cleaning water through nozzles 17 of each of 5, 15, 16.

A sensor S is attached to the lower side of the cake thickness adjuster 12 so as to be able to swing freely around the horizontal axis P with its tip end inserted into the cake placed on the first filter cloth 9.
At the same time, a detector 18 is attached to detect the swing angle of the sensor S, and the signal from the detector 18 is input to the judgment circuit 19.If the cake is soft, the force to swing the sensor S is weak. The detecting device 20 is configured to detect the degree of softness of the cake based on the swing angle of the sensor S based on the fact that the swing angle is small, and on the other hand, if the cake is hard, the swing angle is large.

In the detection device 20, when the degree of softness is detected equal to or higher than the set value, a command signal is input from the determination circuit 19 to the operation circuit 21, the power supply circuit 23 with the alarm device 22 is closed, and the filter cloth 9 is closed. ，
It is configured to operate a stop mechanism 24 for the motor M that drives the filter cloth 13, and when the cake is softer than a setting, it automatically stops the rotation of the filter cloths 9 and 13, and also issues an alarm to notify the user of this. It is designed to notify the operator.

In the above embodiment, the alarm device 22 and the stop mechanism 24 are activated based on the detection of the degree of softness of the cake that is higher than the set value.
However, in the present invention, only one of the two 22 and 24 may be provided, or they may be provided separately or in combination, for example, when the object to be processed is Supply device 3
A variable discharge capacity pump P is provided with an operating mechanism for changing its discharge capacity, and the operating mechanism is automatically operated based on the detection of the degree of softness exceeding the set value, thereby reducing the amount of material to be treated. Various structural modifications are possible, such as configuring it as follows, and these are collectively referred to as a safety mechanism.

Incidentally, a plurality of the sensors S are arranged in parallel in the width direction of the first filter cloth 9, and the difference in the mutual rocking angles of the sensors S is detected, and based on this, the filter of the cake placed on the filter cloth 9 is detected. A dual-purpose configuration may be used to detect the difference in thickness in the cloth width direction.

In addition, the detection device 20 may be configured to continuously detect the degree of softness based on the swing angle of the sensor S. , it may be something like opening and closing that limit switch.

In summary, the present invention provides the above-mentioned dewatering apparatus with a device 20 for detecting the degree of softness of the cake sent out from the gravity dehydrating section 11 on the filter cloth 9, and setting by the detecting device 20. It is characterized by being equipped with a safety mechanism that automatically operates based on the detection of the degree of softness exceeding the value.

In other words, before sending the cake to the forced dewatering section 14, the degree of softness of the cake placed on the filter cloth 9 is detected, and appropriate measures are taken based on the results, such as issuing an alarm or stopping the rotation of the filter cloth 9, so that the cake does not flow. This prevents the cake from being sent to the forced dewatering section 14 with high solid content, and prevents the cake from protruding from the side of the filter cloth 9 in the forced dewatering section 14, thereby avoiding a decrease in solid content recovery efficiency and dewatering. We were able to improve performance.

[Brief explanation of the drawing]

The drawing is a schematic vertical cross-sectional view illustrating an embodiment of the dewatering device according to the present invention. 3... Processing material supply device, 9... Filter cloth, 11...
...Gravity dewatering section, 12...Cake thickness adjuster, 14...
... Forced dehydration section, 20 ... Detection device, 24 ... Stop mechanism.

Claims (1)

[Scope of Claims] 1. An endless band-shaped filter cloth 9 is provided in a rotating state from a gravity dehydration section 11 to a forced dehydration section 14, and a device 3 is provided for supplying the material to be treated to the gravity dehydration section 11. The dewatering apparatus is provided with a device 20 for detecting the degree of softness of the cake sent out from the gravity dewatering section 11 on the filter cloth 9, and based on the degree of softness detected by the detecting device 20 being equal to or higher than a set value. A dewatering device characterized by being equipped with a safety mechanism that automatically operates when 2. A cake thickness adjuster 12 is provided to make the thickness of the cake fed from the gravity dewatering section 11 on the filter cloth 9 constant in the longitudinal direction and the width direction of the filter cloth. The dewatering device according to claim 1, wherein the detection device 20 is provided on the lower side. 3. The dewatering device according to claim 1 or 2, wherein the safety mechanism is a mechanism 24 that automatically stops rotation of the filter cloth 9. 4. The dewatering apparatus according to claim 1 or 2, wherein the safety mechanism is a mechanism that reduces the amount of material supplied by the material supplying device 3.