JPH0331489A - 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 transferring the materials to the washing zone of the next stage and washing the materials, then subjecting the materials to a spray washing with fresh water in an intermediate position thereof. 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 while the materials are successively transported through liquid chemical zones 2B, 2D, a washing zone 2F, a liquid chemical zone 2H, and a washing zone 2J; thereafter, the materials are ejected from an outlet part 2K. The materials Q are spray washed with the fresh water 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 washing water is discharged from drain holes 8E, 8I without being cyclically used. The efficient washing is, therefore, executed in the washing zones 2F, 2I 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.

c) Problems to be Solved by the Present Invention] However, in the conventional surface treatment method, as a method to prevent the cleaning effect from decreasing due to an increase in the amount of chemicals brought into each washing tank, the final tank of each washing tank is Either fresh water is simply supplied to the process and the process is carried forward sequentially, or water is supplied while also washing the adhering water by spraying onto the treated material, and the process 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;
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 3] The present invention attempts to solve the above-mentioned drawbacks of the prior art, and its purpose is to efficiently clean processed objects to which chemical solutions have adhered, and to The purpose is to maintain the level of contamination of the washing water at a sufficiently low level (1) so that only a very 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 processing section containing a chemical solution, and to prevent the surface treatment from adhering to the processing section in the liquid draining section through which the processing section passes when the processing section passes through when the processing section carries out the surface treatment. The chemical solution is spray-cleaned with fresh water, and the contaminated water after spray cleaning is drained from the liquid drain section without returning to the chemical solution tank or cleaning tank.

[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 subsequent washing section and thoroughly cleaned. However, when it is washed in the cleaning section, the contaminated water adhering to the treated material is removed by the draining section. Since it is sufficiently diluted by spray cleaning, the 'MM' of contamination in the cleaning tank is extremely low.

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

〔Example〕

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, the inlet section 2A, the preliminary degreasing zone 2B, the Torenson ZC, and the main te.
Grease zone 2D, drain zone 2E, first cleaning zone 2
F, a drain zone 2G, a chemical conversion zone 2H, a drain zone 2■, a second cleaning zone 2J, and a processed material outlet section 2K are formed separately, and between each zone from the preliminary degreasing zone 2B to the second cleaning zone 2J, Partition plates IU to IOU are provided.

Spray nozzles 5B, 5D15F, and 5H15J are provided in the chemical processing zones and cleaning zones from the preliminary degreasing zone 2B to the second cleaning zone 2J, respectively, and pumps 3B, 3D13F, 3H, 3J, and feed pipes are provided at the bottom. Liquid tanks IB to 1J are provided which are connected to the spray nozzles 5B to 5J via 4B14D, 4F, and 4H14J.

Further, water cutoff feed pipes 6E, 6G, 6I, 6K are arranged in the drain zones 2E, 2G12I, 2K and connected to mist spray nozzles 9E, 9G, '111, 9K.

Mist spray is flow rate controller MI device 7E, 7G, 717K
It is sprayed by adjusting the flow rate.

Drain holes 8E, 81 are provided in the drain zones 2E, 21.

R is a conveyor for conveying the processed material.

Through the metal coating pretreatment process having the above-mentioned configuration, metal products were subjected to continuous defoaming to chemical conversion treatment.

Processed items are 40 lockers/hour with a surface area of 4.36m' and the surface! 1IO, 64 m'' shelf boards were processed at a rate of 100 sheets/hour.

For 1B and ID, use an alkaline degreasing agent (180 mj in terms of total alkali contamination degree). For IH, use a phosphorous-resistant zinc-based chemical agent (180 mj l in terms of all floor contamination degree). The amount of water drained from 8E and 8I and sprayed with fresh water to 9G and 9 is 43,017 hours and 173 hours, respectively.
After 17 hours, spray powdered ice on each front stage and 8E.
The operation was carried out while draining water from 8I.

As a result of the above operations, the total alkali contamination level in IF was 2-
The total stain resistance in IJ was constant at 0.5-.

[Comparative example]

Next, stop the fresh water spray supply to 9E and 9I, and
, the amount of fresh water sprayed to 9 and 9 was 2180, respectively.
The treatment was carried out under the same operating conditions except that the operating conditions were 1/hour and 88401/hour.

As a result of the above operations, the total alkali contamination level in the IF was 2.
It became constant at d, and the total acid-contaminated dust at IJ became constant at O and S-.

〔Effect of the invention〕

The degree of contamination of the cleaning water of the cleaning sections IF and IJ in the example was equivalent to that of the comparative example, although the amount of fresh water supplied was about 174, and good water quality was maintained.

Furthermore, since the amount of fresh water supplied can be reduced to about 174 ml, an excellent effect can be obtained in that the burden of wastewater treatment is reduced.

[Brief explanation of drawings]

FIG. 1 is a longitudinal side view of a phosphoric acid film chemical conversion treatment line in which the present invention is carried out, IB to IJ, chemical solution or cleaning water tank, IU to IOU partition plate, 28 to 2K, treatment liquid passage zone, 3B~3J・Pump 4B~4J・・Feed pipe,
5B ~ 5 - Spray nozzle, 6E ~ 6 - Fresh water feed pipe, 7E ~ 7 flow JIFl regulator, 8E181
・Drainage hole, 9E~9K Mist spray nozzle, Q・Processed material, R・・Funbear

Claims (1)

[Claims] 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 water washing method for a surface treatment process, characterized in that spray washing with fresh water is performed at a width position from a chemical solution zone to the next washing zone, and the sprayed washing water is drained without being recycled.