The Challenge in Capturing Liquid Smoke

Machining hard metals with straight-oil coolant can generate “liquid smoke” that can be difficult to capture. Here are some factors to consider when developing a mist collection system for this pesky machining byproduct.


At 0.7 micron in size, liquid smoke droplets are almost 30 times smaller than average mist droplets, and capturing them requires a very efficient and well-thought-out mist collecting system.

“Liquid smoke” is created by processes that heat and/or compresses fluids under high pressure, such as machining hard metals with straight-oil coolants. These processes produce a vapor that condenses back into a cloud consisting of liquid droplets measuring as small as 0.7 micron. These are smaller than droplets found in traditional machining mist, although both present health, safety and environmental risks if not properly captured.

In this article, Nick Welter, district manager for Donaldson Torit, provides three steps for developing an efficient, well-thought-out mist collecting system for liquid smoke.