JPS60245792A - Energy saving type surface treatment - Google Patents

Abstract

PURPOSE:To save heat energy for heating liq. chemicals when a material to be treated is treated with the liq. chemicals and washed by spraying water, by spraying water at the outlet sides of washing zones, blowing hot air to evaporate water, and feeding generated steam. CONSTITUTION:Washing water is sent to a spray chamber in each of zones 2D- 2F, 2H-2K. The ratio between the amount of the washing water and the amount of washing water sent to the preceding spray chamber is regulated to 100:(1-0.1), and the washing water sent to the preceding spray chamber is sent to the outlet side of the preceding zone through each of by-passes 9D-9F, 9H- 9K. At the outlet sides of the final zones 2F, 2K, fresh water from supply water nozzles 8W, 8X replaces the stuck water, and the amount of the fresh water is made nearly equal to the amount of water sent to the preceding zone. Hot air is blown from blowing nozzles 14, 14' before liq. chemicals zones 2B, 2G, and gen- erated steam is exhausted together with the hot air by suction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spray-type surface treatment method used for purposes such as, and particularly to an energy-saving surface treatment method.

As a pre-treatment method for degreasing metal products, phosphate treatment, etc., the inside of the tunnel-shaped booth is divided into multiple spray chambers, and each spray chamber is equipped with a spray mechanism and a tank for spray liquid. A method is used in which the material is sequentially transferred from a chemical treatment zone to a subsequent water washing zone by a conveyor, while being washed and chemically treated.

In this treatment method, in order to prevent the cleaning effect from decreasing due to an increase in the amount of chemicals carried into each washing zone, conventionally, fresh hot water is generally supplied to the last zone of each washing zone, and the overflow sequentially flows to the previous zone. However, water was drained from the first washing zone following the chemical zone, but waste water was constantly generated and it was necessary to treat this waste water.

As a countermeasure, the steam is discharged from the upper part of the chemical zone.
Systems have been proposed that balance the amount of surplus water from the water supply by evaporation. Although this method has certain effects, this system alone has the following drawbacks.

■ The amount of evaporation must be adjusted according to the amount of surplus water, which is difficult to control and difficult to balance.

■ Since surplus water is to be discharged through evaporation, a large exhaust capacity is required, but the amount of evaporation is insufficient and it is difficult to produce wastewater.

■ As the essential feature is that steam is discharged directly above the chemical zone, it is not possible to prevent mist from being brought into the washing zone, which leads to uneven contamination of the processed material and contamination of the washing water. .

The present invention overcomes the above-mentioned drawbacks of this type of surface treatment method, makes it possible to perform an efficient treatment with a small amount of displacement through-water (which causes surplus water), and makes it possible to carry out water-saving treatment, as well as to reduce the amount of water that can be sprayed into the downstream zone. The purpose of the present invention is to provide an energy-saving and water-saving surface treatment method that reliably prevents mist from being taken out, significantly reduces uneven contamination of objects to be treated, and furthermore, causes extremely little water contamination and virtually eliminates wastewater. .

In order to achieve this objective, the present invention first creates surplus water in the final cleaning zone as in the conventional method, supplies this to the overflow set sequentially to the chemical tank, and exhausts the surplus water in the chemical zone. (As a method of supplying the moisture extracted as vapor from the chemical zone and the chemical solution or cleaning water that adheres to the surface of the workpiece and is carried out, a binoculars pipe branched from the spray piping of the next stage cleaning zone is used. The amount of spray water is set at a fixed range ratio in relation to the amount of spray water in the next cleaning zone.In other words, the amount of cleaning water sent to the spray chamber in the valley zone is The ratio of the amount of cleaning water sent to the spray room and the front spray room is ioo: (i~01).

This increases the washing efficiency, minimizes the amount of chemicals and washing water brought in from the front zone, eliminates the disadvantages of the surplus water supply system, and enables truly effective wastewater pretreatment.

Furthermore, one of the substantial features of the present invention is that hot air is blown from the outside into the entrance in front of the chemical liquid zone, and during operation at an intermediate position between the chemical liquid zone and the next washing zone, the hot air is It consists in expelling. This prevents outside air from entering the booth entrance, and furthermore, the atmospheric temperature of the chemical zone is maintained high by the hot air, resulting in energy savings in maintaining the temperature of the liquid tank. By arranging the suction position of the generated steam at the above-mentioned part, the air and mist in each washing zone will flow in the direction of the chemical solution zone, making it possible to more reliably prevent the introduction of spray mist and contamination of the washing zone. is significantly reduced.

Embodiments of the present invention will be described below based on the accompanying drawings.

Figures 1 to 3 show examples in which the present invention is applied to degreasing and chemical conversion coating treatment in metal product coating equipment.
A is the degreasing part, B is the chemical forming part, C is the painting part, D is the baking or/
and a drying section, E is a conveyor, and F is a processed object.

The degreasing section A and the chemical conversion section B are configured as a tunnel-shaped booth 1, and in this embodiment, the inside of the booth is divided from the processing object charging side to an inlet section (tray/zone) 2A, a preliminary degreasing zone 2B, a degreasing zone 2B, and a degreasing zone 2B. Zone 2C, 1st washing zone 2D, 2nd washing zone 2E, 3rd washing zone (@final washing zone) 2F,
A chemical conversion zone 2G, a fourth cleaning zone 2H1, a fifth cleaning zone 2I, a sixth cleaning zone 2J, a final cleaning zone 2, and an outlet section 2L are formed separately, and between each zone from the preliminary degreasing zone 2B to the final zone 2K. Boundary zones 2M to 2U for draining liquid are provided.

Spray nozzles 3B, 3C, and 3 are provided in each zone from the preliminary degreasing zone 2B to the final cleaning zone 2K, respectively.
D, 3E, 3F, 3G, 3H.

3■, 3J, and 3K are arranged, and there is a bon 7 at the bottom.
4B-4 are provided with liquid tanks 6B-6K connected to the spray nozzles 3B-3 via feed pipes 5B-5K.

Each of the liquid tanks 6B, 6c, and 6G in the preliminary degreasing zone 2B, degreasing zone 2C, and chemical conversion zone 2G is provided with a chemical solution heating means 7.1' such as an immersion tube burner or a hot water boiler. The preliminary degreasing zone 2B and the degreasing zone 2C are connected by a passage pipe 30, and the filter 3
1.31', each end of a circulation system 34 including a pump 32 and a flotation tank 33 are connected to discharge the degreased oil. - 10,000, Feed pipe 5G and liquid tank 6 of chemical conversion zone 2G
During G, a circulation system 3 equipped with a sludge filter 35
They are connected by 6.

The degreasing zone 2C1 and the first cleaning zone 2D.

The second cleaning zone 2E, the chemical conversion zone 2G, the fourth cleaning zone 2H, the fifth cleaning zone 2, and the sixth cleaning zone 2J are located at the outlet side, that is, from the rear of the spray nozzle in each zone to the boundary zone. To,
Supply spray nozzle 8D, 8E, 8F, 8H, 8I, 8
J.

8K is installed.

The replenishment spray nozzle 8D on the exit side of the degreasing zone 2C is
The first cleaning seam 72D is moved backward by the bypass pipe 9D,
It is connected to the feed pipe 5D connecting the liquid tank 6D of the first cleaning seam 72D and the spray nozzle 3D, and similarly the first cleaning zone 2D
The replenishment spray nozzle 8E is connected to the feed pipe 5E of the second cleaning zone 2E and the second cleaning seat 72 by a bypass pipe 9E.
The replenishment spray nozzles 8F of E are connected to the feed pipes 5F of the third cleaning zone 2F by bypass pipes 9F, respectively.

In addition, the replenishment spray nozzle 8 on the outlet side of the chemical sea 72G
H is the liquid tank 4 of the fourth cleaning zone 2H via the bypass pipe 9H.
Connected to feed pipe 5H connecting H and spray nozzle 3HY,
Similarly, the 8 replenishment spray nozzles in the 4th cleaning zone 2H are connected to the 5 feed pipes in the 5th cleaning zone 2 through the bypass pipe 9, and the replenishment spray nozzles 8J in the 2nd fifth cleaning zone are connected to the bypass pipe 9J. Therefore, the feed pipe 5J of the sixth cleaning zone 2J and the replenishment spray nozzle 8 of the sixth cleaning zone 2J are connected to the feed pipe 5 to the final zone 2 by a bypass pipe 9K, respectively.

As described above (in the present invention, make-up water is forwarded using a feed pipe for the main spray nozzle and a branched bypass pipe. Simply extend the feed pipe and arrange the main spray nozzle and make-up spray nozzle in series. In this case, since the amount of water in the replenishment spray nozzle is much smaller than that in the main spray nozzle, it becomes so-called raindrop-like, and the replenishment spray nozzle cannot form a good mist.

If configured as in the present invention, the pump pressure can be effectively used to spray the zone concerned and make-up water spray to the preceding zone under equal pressure conditions, thereby achieving the desired cleaning and dilution effect.

Each of the above-mentioned pain pipes 9D, 9E, 9F, and 9H.

Control valves 10D, 10E, 10F, IOH, 1, etc. for 9th, 9J, and 9K, respectively (electromagnetic), etc.
0I, IOJ, and IOK are provided, and the control valve '1OD of the bypass W9D is operated by a signal from the level switch 11B provided in the liquid tank 6B of the preliminary degreasing zone 2B. Control valve IOE of bypass pipe 9E
is connected to the level switch IID provided in the liquid tank 6D of the first cleaning zone 2D, and in the same way, the control valve of the No. The control valve 10H of the i9 space W9H is connected to the level switch 11G installed in the liquid tank 6G of the chemical conversion zone 2G, the bypass pipe 9
The level switch 111 of the liquid tank 6I and the level switch 11J of the liquid tank 6J are connected to the I/f switch W9, respectively.

- At each outlet position of the third cleaning zone 2F and the final zone 2, there are fresh water replenishment spray nozzles 8W and 8, respectively.
Each of the replenishment spray nozzles 8W and 8X is supplied with tap water, pure water, etc. through external piping 9W and 9X. And the said replenishment valve V −/
! In order to prevent excess water from entering the third washing zone 2F and final zone 2K due to replenishment from pipes 8W and 8X, abnormal high water level activation valves 12A and abnormal low water level activation valves 12B are installed in piping 9W and 9X, respectively. It is electrically connected to the water level switch 13A and the low water level level switch 13B. .

Abnormally high water level operation pulp 12A is normally open,
The high water level switch 13A is closed to stop the water supply, and at the same time an alarm is issued. The abnormally low water level activation pulp 12B is normally closed, and is opened by a signal from the low water level level switch 13B to supply make-up water and at the same time issue an alarm.

Furthermore, the present invention provides for the inlet side of the chemical zone, that is, in this embodiment, the inlet section 2A in front of the preliminary degreasing zone 2B and the boundary zone (hereinafter referred to as inlet section) 2Q in front of the chemical conversion zone 2G. Inlet ports 14 and 14' for hot air (waste heat) led from outside are provided.

The air inlet 14, 14' is preferably provided in the lower region in the height direction of the booth, and may be configured as a simple opening, but may also be a slit-shaped or spray-shaped nozzle. Further, the number of arrangement is arbitrary, and the arrangement side is also free, such as on one side wall of the booth or on both sides of the booth.

The blown hot air may be of any type as long as it has a composition that is suitable for chemical treatment, but from the standpoint of energy conservation,
It is preferable to utilize the waste heat generated in the pretreatment and next step treatment targeted by the present invention. In this embodiment, the seizure is caused by exhaust gas from hydrocarbon fuel such as propane used in the drying section, exhaust gas from the chemical heating means 7 and 7' in the degreasing section A and the chemical forming section B, and exhaust air. is used.

That is, in particular, a conduit 16.16' is connected to the exhaust system 15 of the baking and/or drying section, and this conduit 16.
16' to the previous inlet section 14.14' via the blower 17.17' and the control valve 18.18', and the exhaust section of the chemical solution heating means 7.7' to the blower 19.19' and the control valve 18.18'. 20.20' are led to the inlet 14.14' via conduits 16", 16" and connected to the inlet 14.14' via a mixer and a pressure equalizer, if necessary. In addition, if the hot air temperature is too high, evaporation and thermal decomposition will occur, so heat will be generated.

If the wind temperature is too high, it is preferably adjusted to 150 to 200°C by taking in some outside air. Also, depending on the gas components, intermediate phase 2 may be carried out using Z, such as a catalyst.

Furthermore, the present invention not only provides the hot air blowing ports 14 and 14' at the entrance of the busy chemical zone as described above, but also provides an area from the outlet side of the chemical zone to the next cleaning zone, that is, the suction ratio. If the chemical solution side and cleaning side are approximately 5:5~
An intake MS is provided in a region where the ratio is 6:4. In this example,
Intake portions 21 and 22 are provided above each of the boundary portion 2N between the degreasing zone 2C and the first cleaning zone 2D and the boundary portion 2Q between the chemical conversion zone 2G and the fourth cleaning zone 2H. .22 respectively eliminator 23
and an exhaust dust 25 equipped with a road fan 24.

The eliminator 23 includes a degreasing zone 2C and a chemical conversion zone 2.
A return pipe 27 leading to G is provided.

It should be noted that the above-mentioned embodiments are only examples of the present invention.
It can be applied to degreasing equipment alone, chemical conversion equipment alone, degreasing and chemical conversion equipment, etc., and of course also includes increasing or decreasing the number of cleaning stages, omitting a preliminary degreasing zone, adding a hot water washing process or a post-treatment process, etc.

The workpiece F is suspended by the conveyor E and conveyed at a predetermined speed from the entrance 2A to the exit 2L of the booth 1, while passing through the preliminary degreasing zone 2B and the degreasing zone 2C. A predetermined degreasing agent is sprayed by the spray nozzles 3B and 3C in both zones, and then the first cleaning sheet 72D
Spray nozzle 3D while passing through 3rd cleaning noon 2FY
, 3E, and 3F receive the spray 6 of cleaning water, and the highly concentrated chemical solution is washed away.

Next, the slightly processed material F enters the chemical conversion seam 72G, where it is sprayed with a chemical agent by the spray nozzle 3G to form a film, and is sprayed into the fourth cleaning zone 2H or the final cleaning zone 2. The stinging chemical solution is washed away by the washing water spray from the nozzles 3H to 3K.

During such operations, the present invention provides a degreasing section A and a chemical forming section B.
Hot air is continuously blown in from the blow-in ports 14 and 14' provided at the inlet parts 2A and 2Q of the degreasing zone 2C, and the exhaust fan 25 and the load fan 24 are simultaneously driven to perform the first cleaning from the outlet side of the degreasing zone 2C. The internal atmosphere is sucked and discharged by an air intake part 21 provided behind the zone 2D and an air intake part 22 provided from the exit side of the chemical conversion zone 2G to the fourth cleaning zone 2H. The degreasing zone 2c, the first cleaning zone 2D, the second cleaning zone 2E, the chemical conversion zone 2G, and the fourth cleaning zone 2 are used together with the spraying by the above-mentioned spray nozzle.
Replenishment spray nozzles 8D and 8E are placed at each outlet of H1 5th cleaning zone 2 and 6th cleaning zone 2J.

8F, 8H18I, 8J, and 8K have rear spray nozzle feed pipes 5D, 5E, 5F, and 5H, respectively.

Pine conduit 9D connected to 5 engineering, 5J, and 5.

Supply water 6 via 9E, 9F, 9H, 9I, 9J, 9K
send and spray each.

At this time, in the present invention, it is important that the ratio of the amount of water discharged from the spray nozzle 3D and the replenishment spray nozzle 8D sent by the Pinoya conduit is in the range of 100: (1 to 0.1); 3F, 3H, 3I
, 3J, 3K replenishment spray nozzles 8E, 8F,
8H.

Ratio of discharged water i from 8I, 8J, 8K Y100: (1 to
0.1).

The ratio of the amount of cleaning water sent to the spray chamber of each zone to the amount of cleaning water sent to the preceding spray chamber was set to the above range based on the knowledge obtained from actual tests of the method of the present invention.
If the washing water ratio exceeds 0:1', the amount of water supplied will be more than the amount of water that is commensurate with the amount of evaporated water, and not only will it not be possible to perform a substantial water-saving treatment (also, the balance of the chemical solution will be disrupted, and even if other conditions are appropriate, You cannot expect a synergistic effect.On the contrary, it is 100:0.
If it is less than 1, the uneven contamination of the object to be treated will not be improved, and the degree of contamination of the washing water will increase, leading to a decline in quality. In addition, the replenishment spray nozzles 8W, 8 on the exit side to the final zones 2F, 2
Fresh water is supplied to X from external piping 9W and 9X and sprayed. This fresh water supply shall be automatically controlled by high water level and low water level actuation valves.

Accordingly, in this embodiment, the hot air is produced by guiding high-temperature exhaust gas from the baking and/or drying section and exhaust from the chemical heating means 7 through the conduit 16. (If so, the suction port 14
A high-temperature gas curtain is formed in the artificial part of the chemical liquid zone 2B by the jet of hot air from the chemical solution zone 2B, and the intrusion of low-temperature outside air is blocked by this gas curtain. And since the suction and exhaust force is working on the exit side of the degreasing zone 2C as before,
The hot air forming the gas curtain is then forcibly drawn into the degreasing zone 2C, where it flows across the inside of the degreasing zone and is sucked out from the air intake section 21.

At this time, in the degreasing zone 2C, the chemical solution is sprayed by the spray nozzle 3C, but in the past, exhaustion was performed by simply taking in a large amount of outside air at the inlet, and the cooled object to be treated entered and left as it was. Because of this, a large amount of heat was being carried out. However, in the present invention, hot air continuously passes through the degreasing zone 2C to heat the spray mist.

As a result, the entry of outside air is interrupted, and heat is not taken out by the treated object (as a result, the temperature drop of the chemical solution returned to the liquid tank 6C after spraying is significantly reduced. Therefore, thermal efficiency is improved, and the heat source for heating the chemical solution is kept to the minimum required. The fuel ratio will be significantly improved.

Since the chemical solution is sprayed under high temperature conditions in the degreasing zone 2C, the spray mist is vaporized and the volume is about 150.
The steam expands 0 times.

The load fan 2 has an exhaust air volume that is greater than the amount of steam generated.
4, and suction and exhaust is carried out in an area extending from the exit side of the degreasing zone 2C to the first cleaning zone 2D. This exhaust system discharges an amount of water equivalent to the evaporated content in the degreasing zones 2B and 2C and an amount of water equivalent to the amount of spray mist required for the subsequent cleaning zone, and the discharge ratio of these amounts of water is set in advance by the arrangement position of the intake part. be done.

The above is one of the features of the present invention, but simply placing a replenishment spray curtain at the outlet of each zone or providing a direct intake section in the degreasing zone will result in only the vapor being concentrated and being sucked out. Having a replenishment spray in the zone has the negative effect of bringing contaminated water into the next zone.

However, in the present invention, the above-mentioned areas (, degreasing zones 2B, 2
In C, direct exhaust is not performed, but suction and exhaust 7 is carried out at the outlet of the degreasing zone 2C, so the steam generated in the degreasing zones 2B and 2C is drawn together with the hot air blown in while facing moderate resistance by the spray curtain in the degreasing zone. It turns out. As a result, the inside air in the first cleaning zone 2D and subsequent cleaning zones 2E and 2F becomes negative pressure, and the flow of air and spray mist in these zones is directed toward the degreasing zone. Therefore, even if make-up water is sprayed at the outlet of each zone, the mist will not be carried into the next zone, and the highly concentrated liquid that adheres to the workpiece will be reliably washed away with the mist from the next zone. This reduces the level of contamination of the cleaning water.

The above-mentioned effect is almost the same in the chemical conversion part B as well. In other words, a high-temperature gas curtain is formed by the jet of hot air from the inlet 14', which prevents cold mist from entering from the adjacent third cleaning zone 2F, and at the same time prevents the intrusion of cold mist from the workpiece whose temperature has decreased due to cleaning. The temperature of the chemical conversion zone 2G is prevented from decreasing, and the make-up water sprays at the outlet of each zone including the chemical conversion zone 2GY and the mist of these make-up water sprays are prevented from being brought into the next zone.

Next, a specific example of the system of the present invention will be shown.

I Continuous degreasing and chemical conversion treatment of metal products was carried out using the system of the present invention shown in FIG. The surface area of the object to be treated is 0.15
rr? / car parts were processed at a rate of &2000 parts/H.

For degreasing, an alkaline degreaser and a chemical or zinc phosphate chemical agent were used, and the liquid temperature was heated to 50° C. using an immersion tube burner (degreasing) and a hot water boiler (chemical).

■ Inlet ports 14 and 14' are provided in the front zone of the inlet 2A of the degreasing section and in the front zone of the inlet 2Q of the chemical conversion section. - For the latter, a mixed gas of waste gas from the drying furnace and waste heat from the hot water boiler was supplied. During baking, the waste heat from the drying oven is 250℃, which is heated to 11℃ by taking in outside air.
0°C x 30 NM”/min, mixed with waste heat from the immersion tube burner at 300°C x 30 NM3/min,
180℃ x 55NM”/min pressure 100 from the inlet
It was injected with 111Aq. The waste heat of hot water gills is 300℃
This is mixed with the waste heat of the drying oven and heated at 115°C x 30 NMs/min.
, at a pressure of 1001 BAq. Outside temperature is 20℃
It is.

■ The intake parts 21 and 22 are connected to the boundary zone 2N between the degreasing zone and the first cleaning zone, the chemical sea 72G and the fourth cleaning so that the intake ratio is 6:4 on the chemical zone side: cleaning zone side. Provided in boundary zone 2Q between zone 2H,
Limit load fan nominal capacity 115 Ms/m1nX
140 degreasing Aq (degreasing), 132 M'/min X1
It was evacuated with 60 Aq (Kasei).

Dish The amount of water discharged by the intake section 21 of the degreasing section is approximately 22
At 0 A/H, the amount of water taken out due to adhesion of the treated material is 301
It was J/H. Therefore, the first flushing water of 2101/H was used.
The degreasing zone outlet is sprayed from the liquid tank of the cleaning zone 2D via the bypass pipe 9D' and the replenishing spray 8D, and the amount of spray from the main spray nozzle 3D is 900001/H (10
0:0.23). Similarly, the output bypass pipe 9E of the first cleaning zone 2D and the replenishment spray 8E
1/H and sgelage 2501/H tap water at the outlet of the third cleaning zone 2F using a replenishing spray 8W.
10700 spray lids from main spray nozzles 3E and 3F
07/H (100:0.23). The amount of water discharged by the intake section 22 of the chemical conversion section is 180 A/H, and the amount of water brought in due to adhesion and the amount of water taken out are offset, so the amount of water discharged is 180 A/H.
The cleaning water is transferred from the liquid tank of the fourth cleaning zone 6H to the bypass pipe 9.
H, spray at the outlet of the chemical conversion zone using the replenishment spray nozzle 8H, and increase the amount of spray from the main spray nozzle 3H to 7700.
0 [/H (100:0.23). The following equal amounts of cleaning water are sequentially sprayed at the outlet of the front zone using the downstream liquid tank or bypass pipe and the replenishment spray nozzle, and the final cleaning zone is replenished with pure water "Y 18017H Tespray", and the main spray nozzles 3■, 3J , the spray amount from 3K is 77,000
The ratio was A/H (100:0.23).

■ As a result of the above operations, the total amount of make-up water is 4301/hour.
This is about 1/20 or less of the amount of fresh water that would be required if fresh water was supplied in each zone! 1/2 of the case where the surplus is made in the final zone and sent forward to an overflow set or overspray type.
It was ~1/3 or less. And the amount of degreaser used is 1/3
The amount of chemical agent used decreased by 20% to 30% or more, and the degreasing state and the chemical conversion coating state of the treated object were also good.

Further, the indoor temperature of the degreasing zone 2C was stably maintained at 50±5° C., the indoor temperature of the chemical sea 72G was stably maintained at 50±1° C., and the fuel ratio was about 315 when the present invention was not adopted.

According to the present invention as described above, it is possible to prevent the temperature drop in the chemical liquid zone and to significantly reduce the thermal energy for heating the chemical liquid, and it is also possible to prevent mist from being carried in by hot air suction by the rabbit, and to improve the washing efficiency. Or, it can be done completely without wastewater treatment. In particular, as hot air is used, baking can effectively utilize the waste heat of a drying oven or a chemical heating means, so it also achieves appropriate energy savings and has excellent effects such as reducing processing costs.

[Brief explanation of the drawing]

FIG. 1 is a plan view schematically showing one embodiment of the energy-saving surface treatment method according to the present invention, FIG. FIG. 3 is a longitudinal sectional front view of the degreasing section inlet in FIG. 2; 1...Booth, 2A, 2Q...Entrance, 2B, 2
C, 2G... Chemical zone, 2D, 2E, 2F, 2H, 2I, 2J, 2K. ...Washing zone, 3B-3K...Spray nozzle,
5B~5K...Feed pipe, 6B~6K...Liquid tank, 8D
, 8E, , 8F, 8H, 8I, 8J, 8K. 8W, 8X...Replenishment spray, 9D, 9E, 9F, 9H, 9I, 9J, 9K...
Bino 4 pipe, 14.14'...Inlet, 21.2
2...Intake part. Patent applicant Wako Plant Co., Ltd.

Claims (1)

[Claims] 1. In a spray-type surface treatment method in which a metal surface is treated with an aqueous solution containing a chemical agent and then washed with water in multiple stages, the cleaning solution with water in multiple stages is sent to the spray chamber of each zone. At the same time, it is sent to the outlet side of the front stage zone of each zone by bypass, and the adhering water is replaced with fresh water at the outlet side of the final zone in approximately the same amount as the amount sent to the front stage in each zone. An energy-saving surface treatment method characterized by sucking and discharging generated steam together with the hot air during operation in a chemical zone or an intermediate position between the chemical zone and the next cleaning zone while blowing hot air into the surface from the outside. 2. The ratio of the amount of washing water sent to the spray room of each washing zone to the amount of washing water sent to the previous spray room is 100: (1 to 0
. , 1). 3. The energy-saving surface treatment method according to claim 1, wherein waste heat from a baking furnace, a drying furnace, a deodorizing device, a chemical solution heating means, etc. is used as the hot air source.