Sustainability through Reuse — A Q&A with Snehal Desai, Global Business Director, Dow Water & Process Solutions

snehal-desaiDow Water & Process Solutions’ Minimal Liquid Discharge model is a set of proven water filtration technologies and processes that enable companies and municipalities to achieve up to 95 percent liquid discharge recovery. In June, the company was a recipient of the 2016 US Water Prize from the US Water Alliance for its work in resource recovery and sustainability. Earlier this summer, we caught up with Snehal Desai, global business director at Dow Water & Process Solutions, to chat about innovations in water reuse, Dow’s global sustainability initiatives and the market for reuse technology that is rapidly growing in acceptance across the globe.

What are some of the big trends right now surrounding water reuse?

There’s a huge amount of conversation and implementation going on in water reuse. What we’re seeing are really big projects going on all over the world, whether it’s work in power plants, the coal-to-chemical industry in China, or municipal projects going on in the United States with reclaiming or reusing water. There’s an open debate around doing indirect or direct-potable reuse. The whole conversation is around being much more efficient with the water we have. In many ways that’s a municipal conversation. But in the industrial sector, it’s also become a high-priority topic.

Is that due to greater demand for alternative water resources?

Almost anywhere you look, there’s an increasing pressure on pricing. People want to reinvest in infrastructure, and because of that, there’s a need to charge the real price of water. And in some communities, you just can’t. So the pressure really ends up in the industrial sector. You’re seeing an aggressive adoption of different water management strategies, and water reuse is one of those. I see [reuse] as probably one of the megatrends to accomplish this whole notion of how to get 40 percent more water by 2030. With that comes more efficiency, but a critical piece is water reuse.

Talking about water reuse, where have the major growth areas been? Technological advancements? Owner acceptance?

It’s all of that, but they feed each other. Meaning, technology for water reuse in its broadest sense has been here – ultrafiltration, microfiltration, reverse osmosis (RO), ultraviolet, ion exchange, etc. These are all things we know.

Some of the more progressive utilities or industrial customers had started to employ schemes a while ago. That allowed the regulators and the users to get a little more comfortable. Also, with drought conditions and the acceleration of climate change impacts, I think people are starting to see [reuse] as a resilience tactic. It’s not just a nice thing to do. Utilities are starting to realize that even if they have all the water they need, that doesn’t mean it’s going to be all the water they need five years from now. The regulators, utilities and communities have become a little more open to the notion that there might be reused water in their aquifer and maybe even some day coming out of their tap.

How has this evolution impacted Dow’s business?

With our innovation portfolio in the last four to five years, we still focus on energy reduction. With our ECO product line for RO or our SEAMAXX product line for seawater desalination, those were really designed around energy reduction because energy is the main operating cost factor. We’re still continuing to work on that, but what’s probably replaced it to some extent in our portfolio is the issue of enabling water reuse and how to get water to essentially last longer in harsher environments. Our portfolio of various technologies allows OEMs, end-users and engineering firms to put the right combination together based on their needs. The conditions dictate the solution. Some of the developments we’ve done lately are to build more into that suite of solutions.

What misconceptions exist with water reuse?

The terminology is not really confusing to utilities when it comes to water reuse. They get what it’s about. But they also know that in every state or community, there’s a different set of accepted regulations of what you can and can’t do with treated water. It’s fast approaching that the utilities won’t get the questions, but what they need is support from manufacturers and other stakeholders to help in the conversation with their regulators, and then ultimately with their stakeholders, to tell them why this is a path that is safe and that it meets all requirements from a quality perspective.

What is the market like in the United States compared to some other countries? Is it ahead or lagging behind?

I don’t think the U.S. is behind, but I would say that water reuse or minimal liquid discharge as an approach is much earlier and often part of the conversation in a place like China, for example. In Europe, we’ve had a long history of working with clients who are in one way shape or form, recovering the streams that they have in their plant. They don’t call it water reuse. They might classify it as water efficiency. Our early fouling resistant RO membranes were developed for those types of customers. So it depends around the world, and it always depends on the local conditions and if the local community sees it as a challenge. It’s happening everywhere, it’s just happening in different ways.

Does the regulatory environment affect manufacturing?

Certifications like NSF and traditional drinking water standards still apply. If you can say that your products meet that certification, and you can produce the quality on the other end, that’s helpful because we’ve accepted [those certifications] as being the rational mark of quality for drinking water standards. We’re not choosing to have a different set of specifications on the products that we make – that goes for our ion exchange products, our RO products and our ultrafiltration products. But when it comes to proving efficacy, our technology has to be able to comply. Utility operators also have their own set of conditions as far as what they can and can’t do. Real time monitoring and the future of smart water and remote sensing is going to help those areas.

How does desalination fit into the discussion? Does it compete with reuse?

Not exactly. First of all, the industry has made a significant amount of progress in desalination in the last 10-15 years. The cost has gone down by about 50 percent and it’s much more affordable today. But desal is still only an option for so many people. Broadly speaking, the opportunity for reuse feels like it’s larger because you can scale it up and down. Desal is typically done at a large and where the community can afford the price for the water. If you’re doing it inland, brine management ends up being one of the big challenges. If you have the ocean right there, desal ends up being a good option.

Overall, desal is a market that is still growing, but is definitely done in pockets all over the world. The Middle East, California, Australia, China and South America are places where it will continue to be a very viable option. Interestingly enough, in the case of desal, if you’re spending time and energy to pull water out of the ocean, you could do it in combination with reuse. Now that you’ve taken it out, why only use it one time and send it back into the ocean? So a lot of the projects popping up are desal plus reuse, not desal or reuse. So there are a lot of considerations.

What do you see as the next step in reuse, and what is Dow working toward?

We’re working on both the technology and the integration of the technologies into a process flow sheet, and helping people understand the right order and right sequencing of individual component technologies to be able to get the best value out of them. The minimal liquid discharge approach that we’re advocating for isn’t something that says “Use these four products in exactly this way every single time.” What it’s saying is, depending on your feed, you might start with ultrafiltration, or depending on the salt content, you might use a combination of RO and nanofiltration, etc. Those things, from a process engineering point of view, are really where there is going to be a lot of learning and growth. I think the projects will get bigger, but these technologies can be scaled down.

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