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Towards an innovative galvanic industry

Final Report Summary - TIGI (Towards an innovative galvanic industry)

Emulsion pertraction technology (EPT) is introduced for the galvanic industry in Europe. With innovative EPT 8000 of the metal platers in Europe enhance the lifetime of the passivating baths from six weeks to two years. In this way the galvanic industry can cope with the following problems: environmental, economical issues, and drain of work to low wages countries. EPT, removes the tramp ions from the passivating bath, keeping the bath quality at a constant level, during 24 hour operation.

Work performed:

Work package (WP) 1: Determination of the inflow of tramp ions in the passivating bath

Although hampered by the reaction on the financial crises by the SME partners, this was established at all SME partners.

WP2: Research on the technical aspects of EPT, product quality and modelling of the PT process

All passivating bath were tested and the transfer coefficient was determined, next to extensive other research. The mathematical model was developed and tested in multiple runs. It was demonstrated that the product quality benefits from treatment with EPT.

WP3: Design and detailed design

In the research and development design of the EPT unit, multiple improvements were discovered during testing the first unit under factory conditions. These improvements were implemented in the other units during the manufacturing phase of the project. The research and development design of the EPT unit is transformed in a compact industrial design, which has advantages over the research and development design.

WP4: Long term testing

At the locations of the metal platers, the EPT unit were tested on the removal capacity of tramp ions. Results were that the EPT maintains the concentration of tramp ions on a stable level. Five out of seven SMEs participated successfully in the long term test, in two cases the results will be provided after the project has ended. Furthermore, using the WP4 results in various calculations for the parameters of the scientific and technical objectives, defined in the DOW, showed that almost every parameter of those objectives was outperformed by the EPTs.

WP5: Technical, economical en environmental evaluation

Technical evaluation: EPT performs well under the right conditions. The following parameters were assessed: concentrations of tramp ions stabilised by means of the EPT at all locations, tramp ions enrichment factor (should be > 1, Selectivity Cr/Fe and Cr/Zn, transport coefficient and mass transport, passivating bath life time extension, waste reduction and product quality. Almost every parameter was reached. Four out of six calculated ROS were within the limit, so was the price of the EPTs. Three LCA scenarios with EPT proofed to be better than the one without EPT.

WP6: Dissemination and exploitation

The final dissemination plan and the exploitation plan were brought together. The scientific dissemination is separated from the main effort as this is a different world compared to the planned commercialisation. Several peer reviewed publications were produced. The dissemination plan is the description of the strategy to be followed. All action and costs components are presented in the commercial plan section.

Project context and objectives:

Project context

The galvanic industry in Europe is facing three major problems: environmental pollutions, economical issues and drain of work to low wages countries. To support this industry sector in overcoming the mentioned problems, the EPT is introduced for the galvanic industry in Europe. With innovative EPT 80 % of the metal platers in Europe enhance the lifetime of the passivating baths from six weeks to two years and improve their product quality significantly. In this way the galvanic industry can solve their problems.

Project objectives

The overall purpose of the project is to greatly enhance the competitive power of the European galvanic industry, by implementing emulsion pertraction technology for this sector.

From this purpose the following strategic objectives are derived:

1. extend the life time of passivating bath and new Cr (VI) free passivating bath liquids now being six to 12 weeks with at least a factor ten (estimate up to two years), directly resulting in a decrease of operational costs;
2. reduce the current waste quantities, produced from spend passivating baths, by 90 %, directly resulting in a contribution to preservation of the environment;
3. improve product quality of the passivating operation by reducing off spec products in terms of insufficient corrosion resistance by 90 %, leading to a competitive advantage towards technological less advanced galvanisers in low wages countries.

The scientific objectives are:

1. develop a modeling theory for mass transfer in the EP process and identify rate limiting steps;
2. the mass transfer for the tramp ions Fe and Znis targeted as 150 mg/h and 4g/h per standard membrane module with 19.6 m2 membrane area;
3. determine the mechanisms of extraction, regeneration and selectivity of extractants newly developed Cr(VI) free baths;
4. establish the top three parameters determining the mechanisms influencing product quality.

The technological objectives for the EPT technology and methodology are:

1. extend the life time of passivating bath and new Cr (VI) free passivating bath liquids from now being 6 to 12 weeks with a factor ten, resulting in a decrease of operational costs;
2. reduce the current waste quantities from spend passivating baths, by 90 %, resulting in a contribution to preservation of the environment;
3. improve product quality of the passivating operation by reducing off spec products in terms of insufficient corrosion resistance by 90 %, leading to a competitive advantage on the world market;
4. the target price of EPT unit, for an average SME, is around EUR 45 000 to EUR 60 000;
5. economical feasible process with a payback time of one year.

Outsourcing: the project offers a solution to the galvanic industry community regarding a European problem. 80 % of all metal platers utilise one or more passivating (the last process step in the galvanic line) bath during their daily production, e.g. in the whole of Europe the production of large low quality galvanised products has decreased enormously, due to the competition of the low wages countries. Therefore, technological advance leading to an innovative minded galvanic industry, producing high quality products for industrial sector.

Project results:

The following of the main scientific and technological foreground is presented:

1. Research regarding the selective extraction and transfer of tramp ions from the passivating liquid to the extractant:

- a mathematical model developed for mass transfer calculations from batch EPT tests;
- selection extractant and possible influence by concentrations of Cr3+ and Co2+, complexing agents, optimal pH, and temperature;
- experiments regarding the selectivity of the removal of tramp ions versus Cr3+, the loading capacity and the stripping behaviour of the strip acid, and the mechanisms behind it were investigated;
- experiments with various types of passivating bath liquids using a bench scale emulsion pertraction installation are performed and the transfer coefficient for all passivating liquids has been calculated;
- the long-term stability of extractants, membranes and modules were tested under plating shop conditions;
- research on organics accumulating in the passivating bath and the control mechanisms;
- operational parameters for optimum bath quality and operation are determined;
- tests regarding the improvement of the phase separator are executed, improvements are quantified;
- the complete regeneration of strip acid was investigated and the purity and use for the regenerated components is established;
- experiments regarding quantification of the stripping and regeneration of the organic phase were performed;
- a method for purification of the extractant was developed.

2. Modeling the EPT process:

- a mathematical model that describes the EPT applied to the regeneration of trivalent chromium passivation baths has been obtained,
- the model is able to describe the state of zinc and iron concentrations in the passivation baths as a function of nine operation variables,
- the model has been tested successfully at laboratory scale for twelve different passivation fluids used by six SME partners of TIGI project,
- it has been proved that the model enables the description of the operation of EPT units both at laboratory scale and industrial scale. The model can simulate the complete EPT operation.

3. Design and manufacture:

- the detailed design with the implemented improvements. The transformation of the research and develpment design in a compact industrial designs.

4. Long term testing of the EPT units at the metal plates locations:

- the long term testing; at five locations the test was performed. Concentrations of the tramp ions in the bath were maintained at stable level by the operating EPT;
- the achievement of most of the scientific and technical objectives (from DOW).

5. Evaluation:

- technical evaluation: tramp ions Fe3+ and Zn2+ were removed to a satisfactory stable level by the EPT;
- tramp ions enrichment factor (should be > 1) range for iron 4.1 - 19.5 , for zinc 3.9 - 15;
- selectivity Cr/Fe and Cr/Zn, at successful long term test locations, exceeded l requirements from DOW (1:100);
- transport coefficient for iron: 1.1E-08 – 5.9E-08 for zinc 9E-09 – 7.4E-08;
- mass transport for GTV, Proton, Loko, Vargarda (zinc only) and Zinper exceeded the requirements from the DOW;
- passivating bath life time extension at GTV. Loko, Proton two years. Expected extension Zinper and Galdesa > two years;
- waste reduction.GTV Loko, Proton and Zinper 100 %, Vargarda 50 %;
- raise product quality: proven.

Economic evaluation: The return on investment time is between 1 and 1.3 years for the standard EPTs used in this project.

The price of those EPT is within the range specified in the DOW. The environmental evaluation: the result, obtained by LCA analysis, from all three scenarios where EPT is involved is compared, with the scenario without EPT, is that that the passivation practice in the zinc electroplating process benefits from the integration of the EPT.

Potential impact:

The potential impact of the EPT unit for the galvanic industry are:

1. extend the life time of passivating bath and new Cr (VI) free passivating bath liquids with at least a factor ten (estimate up to two years), directly resulting in a decrease of operational costs;
2. reduce the current waste quantities, produced from spend passivating baths, by 90 %, directly resulting in a contribution to preservation of the environment;
3. improve product quality of the passivating operation by reducing off spec products in terms of insufficient corrosion resistance by 90 %, leading to a competitive advantage towards technological less advanced galvanisers in low wages countries.

This is especially important given the fact that according to EIPPC there is no solution for the problem of the discharge of the passivating baths. After discharge, the bath are treated in the neutraliser and deposition facility of the metal platers, thereby causing hazardous waste.

There are signs that the potential impact of the project up to now is not tangible in the socio-economic area. For this to be tangible, a lot of EPTs should be sold first so that the financial benefits for the metal platers can be used for creating jobs. The interest in EPT is growing multiple appointments for relationship building and direct sales have been made.

The main issue is the continuation of the financial / economic crises. This is not a climate for investment in personnel; the insecurity at the metal platers is still large. If personnel is hired, this is done via employment agencies for East Europeans.

The main dissemination activities are the presentations given by TNO, Ondeo, UC and Swerea. Scientific publication containing sensitive information is banned! UC has the lead in scientific publications that do not contain these details. Six publications, peer reviewed, have been written and published.

The exploitation of the results: the cooperation of the consortium with the world leading enterprises are resulted in the first purchase of a custom designed EPT which is build for the customer in the first half of 2012.