JPH0642960U - Pretreatment device - Google Patents

Abstract

(57) [Summary] [Purpose] The sludge settling at the V-shaped bottoms of the pretreatment tank is not allowed to rise into the pretreatment tank, but is allowed to flow from the sludge discharge pipe connected to the V-bottom together with the treatment liquid. At the same time as suctioning and discharging, sludge in the processing liquid sucked and discharged from the sludge discharge pipe is efficiently removed. [Structure] Automatic valves 8a to 8d that sequentially open and close at regular time intervals are provided on the drainage pipes 7a to 7d connecting the V-shaped bottoms 4a to 4d of the pretreatment tank 1 and the sludge discharge pipes 6, respectively. Thus, the flow velocity of the treatment liquid sucked from the V-shaped bottoms 4a to 4d to the sludge discharge pipe 6 is increased, and the pretreatment tank 1
The sludge is prevented from soaring inside, and the sludge separation efficiency of the centrifugal separator 13 provided in the sludge discharge pipe 6 is also increased.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pretreatment device for performing a pretreatment for painting or plating.

[0002]

[Prior art]

 The pre-treatment device for pre-treatment of automobile coating is the treatment of degreasing liquid and film forming liquid etc. stored in the main tank of the pre-treatment tank for large objects such as automobile bodies that are transferred on the hanger of the conveyor. It is designed to be immersed in liquid. A plurality of V-shaped bottoms for accumulating sludge that settles on the tank bottom are formed on the bottom of the main tank, and the sludge accumulated on the bottom is sucked out of the tank together with the treatment liquid at each V-shaped bottom. The sludge discharge pipe is connected, and the treated liquid discharged from the sludge discharge pipe is passed through a filter such as a settling tank to remove the sludge, and then returned to the main tank again. 63-761).

[0003]

[Problems to be solved by the device]

 However, filters such as settling tanks do not have very good sludge removal efficiency, and sludge that has settled and accumulated at each V-shaped bottom of the pretreatment tank is sucked all at once by the sludge discharge pipes. There was a problem that the flow rate of the processing liquid sucked from the sludge to the sludge discharge pipe was slow and sludge once settled at each V-bottom rose again.

Therefore, the present invention allows the sludge settling at each V-shaped bottom of the pretreatment tank to be sucked and discharged from the sludge discharge pipe without rising, and at the same time, the sludge sucked and discharged from the sludge discharge pipe can be efficiently removed. This is a technical issue.

[0005]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention provides a pretreatment device provided with a sludge discharge pipe for sucking and discharging sludge settled from a plurality of V-shaped bottoms forming the bottom of the pretreatment tank together with the treatment liquid. In the above, the sludge discharge pipe is provided with a centrifuge for removing sludge in the treatment liquid, and the drain pipes connecting the sludge discharge pipe and the V-shaped bottoms are arranged at regular time intervals. It is characterized by an automatic valve that opens and closes in sequence.

[0006]

[Action]

 According to the present invention, the sludge contained in the treatment liquid sucked and discharged from each V-shaped bottom forming the bottom of the pretreatment tank through the sludge discharge pipe is efficiently removed by the centrifuge. In particular, in the present invention, there is an automatic valve provided in each drainage pipe that connects each V-shaped bottom for accumulating sludge in the pretreatment tank and a sludge discharge pipe for sucking and discharging the sludge from the V-shaped bottom. The sludge concentration in the centrifuge is kept constant because the sludge concentration in the treatment liquid sent to the centrifuge installed in the sludge discharge pipe is constantly maintained at a certain level by opening and closing the sludge at regular intervals. Is remarkably good.

That is, when the treatment liquid is sucked and discharged all at once from each V-shaped bottom of the pretreatment tank, the sludge separation efficiency of the centrifuge decreases because the concentration of sludge contained in the treatment liquid is low. However, as in the present invention, wait until a certain amount of sludge settles and accumulates at each V-shaped bottom of the pretreatment tank, and then suction and discharge the treatment liquid in order from the V-shaped bottom where the sludge settles and accumulates, the treatment. The sludge concentration in the liquid is increased and the sludge separation efficiency of the centrifuge is improved. Further, if the treatment liquid is not sucked simultaneously from the respective V-shaped bottoms but is sequentially sucked, the flow velocity of the treatment liquid is increased and the sludge settling at the V-shaped bottoms is prevented from rising.

[0008]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flow sheet diagram showing an example of a pretreatment device according to the present invention, and FIG. 2 is a time chart showing an opening / closing operation of an automatic valve according to the present invention.

In the figure, reference numeral 1 is a pretreatment tank consisting of a main tank 2 for immersing an object to be treated in a treatment liquid, and a sub-tank 3 for storing the treatment liquid overflowing from the main tank 2. A plurality of V-shaped bottoms 4a, 4b, 4c and 4d for accumulating sludge settling on the tank bottom are formed on the bottom of No. 2 and the sludge settled and accumulated on each of these V-shaped bottoms 4a to 4d is formed. A sludge discharge pipe 6 sucked and discharged by the pump 5 is connected via drainage pipes 7a to 7d provided for the respective V-shaped bottoms 4a to 4d. Further, automatic valves 8a to 8d such as electromagnetic valves that are sequentially opened and closed at fixed time intervals are installed in the drainage pipes 7a to 7d that connect the sludge discharge pipe 6 and the V-shaped bottoms 4a to 4d, respectively. Has been done.

Next, 9 is a forward pipe 11 for sending the treatment liquid in the pretreatment tank 1 to the heat exchanger 10, and a return pipe for returning the treatment liquid heated in the heat exchanger 10 to the pretreatment tank 1 again. The sludge discharge pipe 6 is formed on the forward pipe 11 and the sludge contained in the treatment liquid discharged from the sludge discharge pipe 6 is supplied to the forward pipe 11. A centrifuge 13 for removal is interposed, and a clean treatment liquid from which sludge has been removed by the centrifuge 13 is sent to the heat exchanger 10, whereby the heat exchanger 10 It prevents sludge from adhering to the inside, which lowers the heat transmission coefficient. The sludge separated from the treatment liquid by the centrifugal separator 13 is discharged to the outside of the system from the drain pipe 14 provided in the centrifugal separator 13.

The return pipe 12 for returning the treatment liquid heated by the heat exchanger 10 to the pretreatment tank 1 again blows a jet of the treatment liquid onto the sludge settling on the outlet side slope of the main tank 2. Is connected to the spray riser pipe 15 that drops into the V-shaped bottoms 4a to 4d, and the sludge that settles on the inlet side slope of the main tank 2 drops into the V-shaped bottoms 4a to 4d. A circulation pipe 18 is connected to the processing liquid that has flowed into the sub tank 3 and returns it to the main tank 2 by a pump 17. Reference numeral 19 denotes a hot water circulation pipe for sending hot water in the hot water tank 21 heated by the steam injected from the steam pipe 20 into the heat exchanger 10 by the pump 22.

However, during operation of the pretreatment apparatus, the automatic valves 8a to 8d are designed to be sequentially opened and closed at fixed time intervals in accordance with, for example, the rotation shown in the timing chart of FIG. The automatic valve 8a interposed in the drainage pipe 7a of the V-shaped bottom 4a is opened for a fixed time necessary for discharging the sludge settled and accumulated in the V-shaped bottom 4a. The next automatic valve 8b interposed in the drainage pipe 7b of the letter bottom 4b is opened for a fixed time similar to the automatic valve 8a. Further, at such a timing, the automatic valve 8c interposed in the drainage pipe 7c of the V-shaped bottom 4c is opened during the opening of the automatic valve 8b, and further, the V-shaped bottom is opened during the opening of the automatic valve 8c. The automatic valve 8d provided in the 4d drain pipe 7d is opened.

As a result, a certain amount of sludge is settled and deposited on the V-shaped bottoms 4a to 4d of the pretreatment tank 1, and the collected sludge is sucked from the V-shaped bottoms 4a to 4d instead. Since it is discharged, the treatment liquid having a high sludge concentration is constantly fed to the centrifuge 13 provided in the sludge discharge pipe 6 without interruption. In particular, the automatic valves 8a to 8d are sequentially opened and closed with a time difference of opening the next automatic valve before closing the previously opened automatic valve so that the two automatic valves are always opened in an overlapping manner. If so, the flow of the treatment liquid sent to the centrifuge 13 will not be interrupted at all, and the separation efficiency of the sludge contained in the treatment will be further enhanced, and the heat exchanger 10 The amount of sludge adhering to the inside is greatly reduced.

Further, if the automatic valves 8a to 8d are sequentially opened and closed, the flow velocity of the processing liquid sucked and discharged from the respective V-shaped bottoms 4a to 4d to the sludge discharge pipe 6 is increased, so that the respective V-shaped bottoms 4a to 4d are increased. It is also possible to prevent the problem that sludge once settled up rises into the pretreatment tank 1.

The treatment liquid sent to the heat exchanger 10 via the centrifugal separator 13 is the lowest temperature treatment liquid discharged from the V-shaped bottoms 4 a to 4 d forming the tank bottom of the pretreatment tank 1. Therefore, the efficiency of heat exchange with the warm water sent from the warm water tank 21 to the heat exchanger 10 through the warm water circulation pipe 19 is also very good. In addition, in the embodiment, the sludge discharge pipe 6 constitutes the forward pipe 11 of the treatment liquid circulation pipe 9 in which the heat exchanger 10 is interposed, but the present invention is not limited to this.

[0016]

[Effect of device]

 According to the present invention, sludge contained in the treatment liquid sucked and discharged through the sludge discharge pipe from the plurality of V-shaped bottoms of the pretreatment tank can be removed very efficiently and at the same time, Since the flow velocity of the treatment liquid sucked and discharged from the V-shaped bottom is increased, the sludge once settled on each V-shaped bottom is prevented from soaring in the pretreatment tank, which is a very excellent effect.

[Brief description of drawings]

FIG. 1 is a flow chart showing an example of a pretreatment device according to the present invention.

FIG. 2 is a time chart showing an opening / closing operation of an automatic valve according to the present invention.

[Explanation of symbols]

 1 ... Pretreatment tank 4a-4d ... V-shaped bottom 6 ... Sludge discharge pipe 7a-7d ... Drainage pipe 8a-8d ... Automatic valve 13 ... ·····centrifuge

Claims (2)

[Scope of utility model registration request] 1. A pretreatment apparatus provided with a sludge discharge pipe for sucking and discharging sludge settled from a plurality of V-shaped bottoms forming the bottom of the pretreatment tank to the bottom together with a treatment liquid.
A centrifuge (13) for removing sludge in the treatment liquid is interposed in the sludge discharge pipe (6), and the sludge discharge pipe (6) is connected to each of the V-shaped bottoms (4a to 4d). A pretreatment device characterized in that each drainage pipe (7a to 7d) is provided with an automatic valve (8a to 8d) which is sequentially opened and closed at regular time intervals. 2. The pretreatment device according to claim 1, wherein each of the automatic valves (8a to 8d) is sequentially opened and closed with a time difference of opening the next automatic valve before closing the previously opened automatic valve.