Episode 42: An Interview with Robin Deal, Hubbard-Hall

As the EPA conducts fact-finding surveys in the metal finishing community regarding PFAS contamination, wastewater treatment is a growing concern for finishing operations. In this installment of Products Finishing’s On the Line interview column, we’re digging into trends in wastewater management. Robin Deal, product manager and wastewater treatment specialist with Hubbard-Hall, recently took some time out of her busy schedule to sit down with PF and discuss the latest in this field.

PF: What emerging technologies or trends are influencing or changing the way we approach the management of wastewater?

 There are so many things going on right now in wastewater that I think some things can get lost. The biggest topic — the most talked about subject in metal finishing wastewater treatment right now — is PFAS. And when people say PFAS, they don’t really realize this is a term for over 9,000 different compounds.

And so, we are talking about how we remove that from our wastewater. But before we can talk about how we remove it, we’ve got to understand where it comes from: Which compounds are in our facilities? Are they coming in on parts or raw material? Are they coming in through chemistry?

And then we got to identify which components we’re looking at and how to remove it. So emerging trends for removal, activated carbon has been successful for some of the forms of PFAS. Electrocoagulation has been successful for some, and advanced oxidation has been successful for some.

So, there’s a huge focus on that right now.

But at the same time, we’re also seeing many people focusing on how they can get to a zero liquid discharge state with their wastewater systems. How do they start reclaiming and recycling their wastewater — especially as we go further west, where water scarcity has become such a huge topic in places like California, Washington state, Oregon, Texas, and New Mexico, Their focus is more on reclamation and how to reuse. So, trends around [recycling and reuse of wastewater] involve things like ion exchange, forward osmosis (not just reverse osmosis), evaporative technologies with condensation collection systems on on top of it.

There are a lot of things going on when we talk about emerging trends — we can go down so many different avenues.

PF: PFAS is such a big topic for finishing operations right now — do you mind talking a bit more about that area of concern?

The problem goes back to the late ‘90s, early 2000s, when the EPA and OSHA got together and said to protect workers from [exposure to] hexavalent chrome plating, we should use a PFAS compound as a fume suppressant. By around 2010-2015, a lot of platers had already moved away from using those compounds, but there are still residual traces of it — in their tanks and their walls and floors. And it leeches out over time into the wastewater. So, there’s only one way that has been tested and proven effective to actually destroy these PFAS forever chemicals, and that is advanced oxidation.

Advanced oxidation uses peroxide and iron, or iron and UV radiation to speed up at the decay of the products. It doesn’t work on all of them, though. It only works on a handful —and it can be pretty expensive.

So, if we can’t destroy the compound that way, what other ways can we use it to remove it from our water? We can do things like activated carbon filtration units, electrostatic carbon filtration, where the carbon (which has a massive surface area, will actually absorb and hold on to the PFAS — it doesn’t destroy it, but it does remove it from the water. There’s also electrocoagulation, where we use electricity and iron as a sacrificial component to filter out and coagulate and precipitate out [PFAS]. So those are a couple of the things that people are looking at.

There’s also a bacterial treatment — where bacteria are used to consume the PFAS as a food source — that’s being investigated.

PF: Can you talk a bit about some of the biggest challenges you see for finishing operations when it comes to navigating some of these issues.

Metal finishers are not in the business of treating wastewater. That’s not what a plater set out to do. That’s not what a paint shop set out to do. They set out to finish goods for the consumer. Wastewater is kind of pushed to the background. 

With other industries like mining and the oil and gas industry, people really look at those industries and the environmental impact, so there is a lot of education for wastewater operator.

I don’t think we educate ourselves enough in the metal finishing industry. I would love to see us have more education around what chemistries we use and how they’re impacted, and how we can become better at wastewater treatment. I think that probably the biggest challenge is that education component. Pulling [the topic of] wastewater from the background and putting it front and center, I think is crucial for our industry.

Also, when we talk about the cost to produce a part, we talk about chemical costs and labor costs, but I never really hear anyone talk about the water cost. How much water does it take to produce a car? 40,000 gallons of water to produce one automobile. We’re not going to stop making cars. So, how can we conserve water? How can we successfully treat that water that becomes waste and reuse it? I think those are some of the challenges that, as an industry, we need to be talking about more.