Antiseptic and bactericidal technology of cutting fluid 1
Nowadays, water-based cutting fluid has been widely used in the metal processing industry, however, the sanitary maintenance of cutting fluid has always been a problem plaguing the majority of production enterprises. The open use environment of water-based cutting fluid and its nutrient-rich formula make it an ideal place for microbial breeding. Although these organisms themselves are too small to be seen by the naked eye, they can bring great harm to production work and personnel health. Therefore, it is necessary to control the growth of microorganisms, whether from a technical or professional medical point of view.
Microorganisms are the early "residents" on the earth and have thrived so far. They have a strong survival ability, from the bottom of the Pacific Ocean with a depth of 10,000 meters and a water pressure of more than 1,000 atmospheres to the atmosphere of 85,000 meters high. From the hot equatorial seas to the cold Antarctic glaciers; Traces of microbes can be found in everything from the high salinity of the Dead Sea to strong acid and alkaline environments. At the same time, there are many kinds of them, and the reproduction rate is extremely fast, for example, Escherichia coli in bacteria can reproduce for about 20 minutes.
Microorganisms can be transmitted through many channels such as dirty water, waste, spilled oil, air, workpieces, operators, and production hygiene defects. They can also enter the circulation system of water-based cutting fluid. Analyzing the formula of the processing fluid, we can find that the elements necessary for microbial growth: carbon, nitrogen, sulfur, phosphorus and tracking elements are present in large quantities in the composition of the formula. Amines are sources of nitrogen, mineral oils and emulsifiers are sources of carbon, sulfates can be found in anionic emulsifiers, and sulfates and sulfonates in water are also sources of sulfur. Sufficient water oxygen in the coolant provides conditions for aerobic metabolism. When the processing fluid is at rest, anaerobic oxygen metabolism of anaerobic bacteria becomes possible. At the same time, the working temperature of water-based cutting fluid at about 20-40 ° C is the ideal condition for microbial growth and reproduction.
The microorganisms detected in the water-based cutting fluid are Escherichia coli, alcaligenes faecalis, Pseudomonas putidis, Aspergillus nigricans, penicillium, candida albicans and so on. Once they proliferate in the cutting fluid circulation system, they will bring great damage, they will degrade organic components, consume emulsifiers, make the oil phase precipitation, the concentration is reduced, and the lubrication performance is also decreased. Caused by microbial fermentation, the PH value is decreased, the anti-rust performance is decreased, and the reproduction of bacteria is further promoted. After sulfates and sulfonates in cutting fluid are decomposed by sulfate-reducing bacteria, hydrogen sulfide gas is produced, which has an unpleasant odor and has an adverse effect on the production environment. In severe cases, microorganisms can form microbial membranes on the wall of the pipeline, becoming stubborn pollution sources, and even blocking the pipeline. The health of on-site operators will also be damaged, skin allergies, and the incidence of wound infections will be increased.
In order to eliminate so many of the hazards mentioned above, corresponding measures must be taken to control the growth of microorganisms. When the bacteria number is between 102 and 104cfu/ml, there will be no problem in the operation of the cutting fluid system in most cases. But for mold, it's a different story. Mold does not distribute evenly throughout the coolant system, but instead forms colonies. This situation can often occur in the cutting fluid system. If mold is found in the cutting system, we must pay special attention to it and take appropriate measures as soon as possible.
