Tips for Green Mass Finishing

Q. We are an environmentally responsible company. We have several projects running to make our company “green.” Others in my company are addressing energy use, but my responsibility has to do with all the fluids we use during manufacturing. This is a big task—we do machining, grinding, heat treating, mass finishing, and washing.

In your area, mass finishing, can you give me some guidelines to reduce the use of non-renewable resources? G.B.

A. I don’t envy your task because “green” is a hot topic fraught with emotional and debatable issues. I infer from your question that the priority here is the environment. It will complicate your project considerably, but I recommend that you give equal, or greater, importance to operator safety.

For you to succeed in your assignment, your company must define “green” for its own purposes. There is no industry-accepted definition at this time, and it isn’t likely that any definition will go unchallenged. Be wary of the term “natural”: Mother Nature is the initial producer of all things, few of which are useable as industrial products without some man-made modifications.

There is no doubt that we should preserve our natural resources, especially those that are allegedly non-renewable. Many cleaning surfactants and rust inhibitors are petroleum derivatives. They can be substituted with plant derivatives. Petroleum-based surfactants used the world over require the productive capacity of our refineries for just four hours a year. I haven’t seen figures estimating how much farm production is required to meet that same demand. As food becomes scarce and expensive, is it responsible to use food sources to fuel our vehicles and clean and rust inhibit our parts?

Manufacturers of process compounds are all, I hope, working toward the goal of environmental responsibility and personal safety. You can obtain statements from your suppliers regarding the steps they are taking, and then determine which products best meet the criteria you have established within your own company. You can establish a general list of ingredients you want to avoid in your products, and ask suppliers to comply in the products they offer to you. There are certain taboos you might consider. Here is a partial list:

No nonoxynol, nor nonylphenol ethoxylates; no phosphorous cleaning agents; no butyl Cellosolve (also known as 2-butoxyethanol, or butyl glycol); no mercury at use level >5 ppb); no DEA (diethanolamine); no nitrites; no halogens except the chlorine in water (halogens are fluorine, chlorine, bromine, iodine, and astatine); volatile organic compounds (VOCs) as measured by EPA Method 24 to be below 5%; pH of products <11, and at use level <9.5; no reportable levels of known carcinogens.

When you are satisfied that the proposed products will meet your company’s requirement for “green,” it is time to measure product performance.

Will these new products interact well with other plant processes? How effectively they clean, rust inhibit, and meet other requirements must be considered. It does no good to select products that don’t work, or which may drive your costs beyond marketability.