Minimization of Health Risks Due to Metalworking Fluid Microbes and Biocides: An Optimal Control System using Microfiltration and Flow Cytometry

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

This grant provides funding for the development of an automated and cost-effective control system to minimize occupational health and safety risks posed by microorganisms and excessive reliance on biocides in metalworking fluid (MWF) systems. First, the research aims to understand the mechanisms that permit membrane-based microfiltration technology to remove microorganisms and associated endotoxin from biocide-free MWFs without disrupting chemical integrity. The research will examine the interactions between MWF chemistry, membrane transport, and ingredient retention. Second, the research will examine a novel application of flow cytometry technology for real-time microbial detection in MWFs. The research will evaluate the physicochemical conditions that maximize flow cytometry performance in MWF applications. Third, an optimal control system will be developed based on flow cytometry and microfiltration. The control system will utilize artificial intelligence methodologies on-line to dynamically predict the required microbial removal rate and optimal microfiltration operating parameters. The control system aims to eliminate microbial-based health risks to approximately 1.2 million workers in the United States. The system would also significantly improve the competitive position of the United States machine tool industry by reducing environmental impact, lowering total machining costs, and minimizing MWF performance variability by enabling contaminant removal and recycling. These considerations are of increasing importance since legislative pressure is mounting at the national level to compel the industry to address the environmental and health risks associated with MWF applications (e.g., EPA Metal Products and Machinery Rule and NIOSH Recommended MWF Exposure Criteria). Recent studies have also demonstrated that total MWF system costs, including acquisition, disposal, and maintenance, are significant in machining, in many cases far-outweighing the cost of tooling. Owing to the technical difficulty removing MWF from manufacturing processes, these drivers will continue to push industry demand for biocide-free microbial control systems and recycling of MWFs to reduce health risks, cost, environmental impact, and performance variability.