Hello everyone!
I am posting to ask for some input from other engineers. I am working on a filtration unit that is having significant foaming issues. What is happening is the foaming is overflowing in the media bed and mixing with the swarf, thus contaminating the return coolant. We have tried several different methods to remove the foam but so far nothing has worked. I have just been assigned to this project and have already heard several different opinions on to what it might be and how to fix it. The most common one, the one I believe is the source, is the sump pump is the issue. This pump was designed to be shut off every so often so it wouldn't burn up the motor but I have come to find out that the pump has been running continuously for several years for all three shifts. That and the water is particularly hard. Logically, this means that the coolant and the defoamant are depleting too quickly since the pump is constantly running, thus not allowing air bubbles to pop in the reserviour, hence the foam. Now, the factors that play into correcting the problem are as follows: we can't switch coolants or switch to a heavier defoamant because it has to go through so many quality checks before it can be implemented; we don't want to spend too much money trying to correct this; and we can't be pulling operators away from their lines to do any maintenance on the units. So my proposition is this: we attach a small, low powered vacuum on the side of the unit along with a sensor somewhere inside the media reserviour to detect foam levels. When the foam get's high enough to cause worry, the sensor will alert the vacuum to switch on. With the vacuum being low powered, theoretically it should be heavy enough to pull part or most of the foam off the top but light enough that it pulls in a minimal amount of coolant and does not suck in the media paper. What I am asking from anyone who views this is to try to poke holes in my solution. I want to be at least 75% sure about this before I propose it to my boss. So please, negative and positive feedback are both welcome. Thanks!