Miljøprojekt, 1114 – Brancheindsats for jern- og metalstøberier - Delprojekt 1 - Organiske bindere og tilsætningsstoffer Fase 1.1: Indsamling og vurdering af eksisterende data

Brancheindsats for jern- og metalstøberier

Summary and conclusions

Background and purpose

The Danish foundry industry uses primarily imported binder systems. Therefore the foundry industry has limited influence regarding environmentally compatible chemical binder systems in the production of cores and moulds. Experience and knowledge concerning application of various binder systems is mainly delivered through product information from binder manufactures, as well as through reports from scientific universities and foundry institutes.

In order to give the foundry industry and authorities a survey of international work concerning development of new environmentally compatible binder systems, summaries are elaborated from articles in the international technical press.

Summaries

The summaries are based on a short extract and source references. The content of the articles primarily focuses on the chemical binder systems’ environmental properties, as well as the binder systems’ technical qualities and the quality of the production.

Conclusion

The technical evaluation of the selected mould binder systems, shows that furan, phenol and alpha-set have good technical qualities compared to water glass. Water glass is a better choice environmentally. The same evaluation results are obtained for core binder systems. Organic based binder systems are better compared to water glass as well, they are, however, worse than water glass in terms of environmental aspects.

During recent years, the development in the environmental field has been centered partly on the development of more environmentally compatible cold-box-binders and partly on the development of binder systems based on alkyl phenolic resin. In a few cases this development has included improvements of the technical properties of water glass binders, or the development of new binder types based on protein and polyphosphate.

Results

Efforts to develop a more environmentally compatible cold-box-binder show that the BTEX concentration at shake-out and the extraction system is reduced by approx. 50 % and 30 % respectively and a minimizing of total C, both by 50 %. Considerable improvements have been reached on odour emissions as well. The odour emission has been reduced from 70,000 to 15,000 GE/m³.

Regarding the development of alkaline catalyzed phenol binders, the environmental advantage of these binders compared to cold-box is that gas emission is used for the hardening of the binder whereas for the hardening of cold-box, Amin is applied. In this connection it should be noted that the cold-box binder contains isocyanate. Regarding strength and production velocity, cold-box is definitely an advantage.

The efforts towards developing new core binders are primarily focused on enabling us to use inorganic material that can be hardened with CO₂, hot air or ultrasound. Emissions at the core production will then drop, while at the same time the emissions are reduced during casting, cooling and shake-out.