Acta Facultatis Ecologiae - Technická univerzita vo Zvolene

74CONCLUSIONEvaluated level of tested MWFs (Emulzin H,Ecocool, BC 25) standards biodegradation by Zahn-Wellenstest achieved 80 % in 10 days, so theyhave potential to ultimate degradation by this test.Tested MWFs samples from the plant pass higherlevel of starting COD concentration instead of this,in the case of Emulzin H and Ecocool sample 2 thelevel of degradation pass 80 % degree.Disadvantages of Zahn-Wellens test are DOCmeasurement by which it is not able to evaluate allpresented organics, even when they are in insolubleform (in the case of COD there is evaluating withoxidable forms also inorganics). At high rate ofadsorption it is impossible to differentiate betweenbiotic degradation and another form of abioticelimination, which was shown in the case of BC25 (28 and 38 % of COD decrease after 3 hoursof cultivating). This method is also discontinual.It will be in the next study, use the modified testmethod of Zahn-Wellens test, by the measuring ofCO 2production and O 2consumption, by continualmeasuring.Substances that are created in the fluid duringmachining operations and adding biocides or otherimpurities such as tramp oil, can affect level of biodegradation.It is required to study also qualitativecontent of cutting fluids and degradation products,to evaluate the potential hazard to humans or theenvironment.Microbial contamination during usage can reducelifetime of MWFs (and also affect workershealth), but on the other hand, there is a possibilityto utilize nonpathogenic microorganisms, that arepresented in fluids, to degrade them. In the nextstudy it will be isolated microbial consortium presentedin specific plant and realize experiments todegrade MWFs at higher concentration rate withfocusing also on the rising products.The preliminary study of ecotoxicity measuringby Lemna minor shows effective concentrationof Emulzin H at the rate of 93 mg/L, for Ecocool99 mg/L and for BC 25 about 150 mg/L. Small concentrationsof tested fluids indicate hormetic effect.It is required to test Emulzin H, Ecocool and BC 25by semi-static or flow-through condition.REFERENCES1. PETTERSSON, A., High-performance base fluidsfor environmentally adapted lubricants In. TribologyInternational 40 (2007) p. 638–6452. WAGNER. H., LUTHER, R., MANG, T. Lubricantbase fluids based on renewable raw materials Theircatalytic manufacture and modification. In AppliedCatalysis A: General 221 (2001) p. 429–4423. Engineering and Design lubricants and hydraulicfluids, Department of the Army U.S. Army Corps ofEngineers, Washington, DC 20314-1000, EM 1110-2-124, CECW-ET Engineer Manual 1110-2-1424, 28February 19994. VERCAMMEN, K., BARRIGA, J., ARNSEK, A.,Summary of results combining biolubricants and lowfriction coatings. Project project contract G5RDCT-2000–004105. BARTZ, W., J. Lubricants and the envirinment. InTribology International Vol. 31, Nos 1–3, 1998, pp.35–47.6. JOHN, J., BHATTACHARYA, M., RAYNOR, P., C.Emulsions containing vegetable oils for cutting fluidapplication. In. Colloids and Surfaces A: Physicochem.Eng. Aspects 237 (2004) p. 141–1507. BASU, B., SINGH, M., P., KAPUR, G., S., Predictionof biodegradability of mineral base oils fromchemical composition using artificial neural networks.In: Tribology International Vol. 31, No. 4,1998, pp. 159–1688. 2005/360/EC – COMMISSION DECISION of 26April 2005 establishing ecological criteria and therelated assessment and verification requirements forthe award of the Community eco-label to lubricants(notified under document number C(2005) 1372)9. MUSZYNSKI, A., ZAŁESKA-RADZIWIŁŁ, M.ŁEBKOWSKA, M., NOWAK, D. Biological andElectrochemical Treatment of Used MetalworkingFluids: A Toxicity-Reduction Evaluation. In. Arch.Environ. Contam. Toxicol. 52, 2007, p. 483–48810. EKENGREN, Ö., NIEMINEN, I., BERGSTRÖM,R. Environmentally acceptable metalworking processes.Ivl Swedish Environmental Vtt Research Institute,2002-01-18, A96291.11. ÁVILA, R., F., ABRAO, A., M. The effect of cuttingfluids on the machining of hardened AISI 4340 steel.In Journal of Materials Processing Technology 2001,No. 119, pp. 21–26.12. GUNTER, K., L., SUTHERLAND, J.,W. An experimentalinvestigation into the effect of process conditionson the mass concentration of cutting fluid mistin turning. In Journal of Cleaner Production. 1999,No. 7, pp. 341–350.13. KO, T., J., PARK, S., H. Experimental verification ofthe mist generation mechanism in turning. In InternationalJournal of Machine Tools & Manufacture2003, No. 43, pp. 115–120.14. SOKOVIC, M., MIJANOVIC, K. Ecological aspectsof the cutting fluids and its influence on quantifiable