JPH0331490A - Rinsing method for surface treating stage - Google Patents

Abstract

PURPOSE:To efficiently rinse treating materials stuck with liquid chemicals with a small volume of washing water by treating the treating materials in a liquid chemical zone, then subjecting the materials to a spray washing with washing water in an intermediate position without cyclically using the water, then washing the materials in a washing zone. CONSTITUTION:The treating materials Q are carried via a conveyor R from an inlet part 2A into a tunnel shaped booth where the materials are treated and washed successively in liquid chemical zones 2B, 2D, 2H and washing zones 2F, 2J; thereafter, the materials are ejected from an outlet part 2K. The materials Q are spray-washed via mist spray nozzles 9E, 9I in the drain zones 2E, 2I in the intermediate position of the washing zones 2F, 2J of the next stage from the liquid chemical zones 2D, 2H in the above-mentioned surface treatment method. The fresh water or the washing water introduced from washing tanks 1F, 1J of the washing zones 2F, 2J is used as the washing water of this time and the washing water is discharged from drain holes 8E, 8I without being cyclically used. The washing efficiency of the washing zones 2F, 2J is enhanced in this way and the accumulation of the contamination in the washing tanks 1F, 1J is decreased and the feed water is saved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for pre-treating metal surfaces, and in particular to a water-saving surface treatment method.

[Conventional technology]

When painting metal products, etc., the base surface is chemically degreased, chemically converted, or treated with chromic acid, phosphoric acid, etc.

In this metal surface treatment, a method is commonly used in which the object to be treated is treated in a chemical treatment section, and then the chemical solution is washed off in a subsequent cleaning section.

[Problems to be solved by the present invention]

However, in conventional surface treatment methods, as a way to prevent the cleaning effect from decreasing due to an increase in the amount of chemicals brought into each washing tank, fresh water is simply supplied to the final tank of each washing tank and the water is sent forward one by one. Alternatively, a method is used in which water is supplied by spraying the material to be treated while also cleaning the adhering water, and the method is carried out sequentially.

The supplied washing water becomes surplus water, overflows in the first stage washing section, becomes waste water, and is discharged outside the process.

In these conventional methods, excess water is returned to the cleaning tank, so
The level of contamination in the cleaning tank is increasing, and a large amount of water is required to keep the level of contamination low.

[Means for solving problems]

The present invention aims to eliminate the above-mentioned drawbacks of the prior art, and its purpose is to efficiently clean the processed material to which the chemical solution has adhered, and to sufficiently reduce the degree of contamination of the cleaning water in the cleaning section. The goal is to maintain low water levels so that only a small amount of fresh water is required.

In order to achieve the above-mentioned object, the present invention has been developed to remove particles that have been surface-treated in a treatment section containing a chemical solution, and to prevent the surface treatment from adhering to the treatment article at a liquid drain section through which the treated article is transferred from the treatment section to the next cleaning section. The chemical solution is spray-washed with fresh water or washing water introduced from the next-stage washing tank, and the contaminated water after spray washing is not returned to the chemical solution tank or washing tank (it is drained from the liquid drain section). It is.

[Effect]

With the above configuration, the treated object is surface-treated in the chemical solution section, then transferred to the liquid drain section and spray-cleaned, and the spray-cleaned cleaning water is drained. After the treated material is spray-cleaned, it is transferred to the next washing section and thoroughly cleaned. However, when it is washed in the cleaning section, the contaminated water adhering to the treated material is sprayed in the liquid draining section. Since it has been cleaned and is sufficiently diluted, the MWI of cleaning tank contamination is extremely low.

This reduces water supply to the cleaning tank, effectively saving water while maintaining contamination level control.

Next, the present invention will be specifically explained based on the accompanying drawings.

Figure 1 shows an embodiment in which the present invention is applied to a metal painting pretreatment process, where 2A is an inlet, 2B is a preliminary degreasing part, and 2D is a pre-degreasing part.
2F is the main degreasing section, 2F is the cleaning section, 2H is the chemical conversion treatment section, 2J is the cleaning section, 2 is the outlet section, and Q is the treated product.

A tunnel-shaped booth is constructed from the inlet section 2A to the outlet section 2, and in this embodiment, from the processing material inlet side to the inlet section 2A and the preliminary degreasing zone 2B.

Drain zone 2c, main tax 111 zone 2D, drain zone 2E, first cleaning zone 2F, drain zone 2G, chemical conversion zone 2H, drain zone 21゜second cleaning zone 2J
1 Processed material outlet section 2K is divided and formed into a preliminary degreasing zone 2.
Partition plates 1υ to IOU are provided between each zone from B to the second cleaning zone 2J.

Spray nozzles 5B, 5D, 5F, 5F' 5H, 5J, 5 are provided in the chemical treatment zones and cleaning zones from the preliminary degreasing zone 2B to the second cleaning zone 2J, respectively.
J' is arranged and pumps 3B, 3D, 3 are placed at the bottom.
F, 30.3J and feed pipe 4B, 4D, 4F, 4H, 4J
Liquid tanks IB to IJ are provided, which are connected to the spray nozzles 5B to 5J via.

Further, fresh water feed pipes 6E, 6G, 61.6K are arranged in the drain zones 2E, 2G, 21, 2K and connected to mist spray nozzles 9E, 9G, 9I, 9K.

Is the mist spray a flow control NI device? E, 7G, and 717K are used to adjust the flow rate and spray.

Drain holes 8E181 are provided in the drain zones 2E and 2I.

R is a conveyor for conveying the processed material.

(Example 1) Continuous degreasing to chemical conversion treatment of a metal product was performed by the metal coating pretreatment process having the above configuration.

The treated items were treated at a rate of 40 lockers/hour with a surface area of 414.38 m'' and 100 shelf boards with a surface area of 0.64 m'' for 7 hours.

For 1B and 10, use an alkaline degreaser (180 m# in terms of total alkali contamination degree), and for IH, use a zinc phosphate-based chemical agent (180 mZ in terms of total contamination resistance degree), stop the spraying of 5F' and 5J', and apply 9E. The amount of fresh water sprayed to 91 is set to 24017 hours each, and the water is drained from 8E and 81, respectively.The amount of fresh water sprayed to 9G and 9 is set to 4301 hours and 1730 I/hour, respectively, and the overflow is sent to the previous stage. The operation was conducted while draining water from 8E and 8I.

As a result of the above operations, the total alkali contamination level at IF was 2I.
! It becomes constant at 1#, and the all-age contamination degree at IJ is 0.5
It became constant at −.

(Example 2) Next, stop spraying fresh water to 9E and 91 and 5F'
The treatment was carried out under the same operating conditions as in Example 1, except that the amount of spray water from 5J' and the amount of fresh water sprayed to 9G and 9 were set to 8B (17 hours, 22901 / hour), respectively. .

As a result of the above operations, the total alkali contamination level on the 1st floor was 2d.
The contamination level of all ages in the IJ remained constant at 0.5-.

(Example 3) The amount of fresh water sprayed to 9E and 9I was adjusted to 24
Under the same operating conditions as Example 1, the amount of spray water from 5F' and 5J' and the amount of fresh water sprayed from 9G and 9 were set as 01/hour and 22,017 hours and 88 (1/hour, respectively). Processed.

As a result of the above operations, the total alkali contamination level at IF was 2d.
The all-age contamination degree at IJ was constant at O and S-.

[Comparative example]

Fresh water spray supply to 9E and 9I and 5F'5J'
Stop spraying washing water from 969 and increase the amount of fresh water sprayed from 969 to 21001/hour and 864/hour, respectively.
The treatment was carried out under the same operating conditions except for a 17 hour period.

As a result of the above operations, the total alkali contamination level in the IF was 2.
It becomes constant at mj, and the all-age contamination degree at IJ is 0.5d.
It became constant.

Table 1 shows the amount of fresh water supplied in Examples 1 to 3 and Comparative Example.

Table 1 Unit (1I hour) 4B~4J-・Feed pipe, 5B~5J Spray nozzle,
6E~6K...Fresh water feed pipe, flow rate mvtm to 7E~7
, BE, 81-・Drainage hole, 9E-9K・Mist spray nozzle, Q Processed material, R conveyor [Effect of the invention] The degree of contamination of the cleaning water of filter cleaning sections IF and IJ in Examples 1 to 3 is a comparative example Even though it was about 15 to 30% of the amount of fresh water supplied, it was the same, and a good amount of water could be maintained.

Moreover, since the amount of fresh water supplied can be reduced by about 15-30%, an excellent effect can be obtained in that the burden of wastewater treatment is reduced.

[Brief explanation of drawings]

Claims (4)

[Claims] 1. In a surface treatment method in which the treated material is introduced into a tunnel-shaped booth and subjected to surface treatment with a treatment solution containing a chemical solution, the treated material is sequentially transferred to the next cleaning zone and subsequent stages for cleaning, etc. A cleaning method in a surface treatment process, characterized in that spray cleaning with cleaning water is performed at an intermediate position between a chemical zone and the next cleaning zone, and the sprayed cleaning water is drained without being recycled. 2. A cleaning method in a surface treatment step according to claim 1, wherein the cleaning water for spray cleaning is fresh water. 3. 2. A cleaning method in a surface treatment step according to claim 1, wherein the cleaning water for spray cleaning is cleaning water introduced from a cleaning tank in a cleaning zone. 4. A cleaning method in a surface treatment step according to claim 1, wherein the cleaning water to be spray cleaned is both fresh water and cleaning water introduced from a cleaning tank in a cleaning zone.