Addressing the 'Water-Energy Nexus' by Improving Manufacturing

• Jun 05, 2015

One of the most pressing environmental issues faced by the manufacturing community resides with the quality and availability of the water it uses in its processes, as well as the quality of the air we breathe in our offices and factories. In many areas of the country, including the arid West, dwindling water supplies, lengthening droughts, and rising demand for water are forcing responsible stakeholders to investigate new ideas, and find and implement these solutions. The goal is to ensure stable, secure water supplies for future generations.

A recent example is the ongoing drought in California that has resulted in unprecedented sanctions on water consumption issued by Gov. Jerry Brown. The residents and businesses in the Golden State are faced with day-to-day limitations with respect to how they use water, while the rest of the country views a cautionary tale of what may be to come.

This concern, and others that address air quality, have brought about large-scale ideas, innovative technologies, and controversial regulations to make immediate and positive impacts on our environment. Innovative technologies can make just as profound an impact as controversial regulations. As you will soon read, much of this can occur at the molecular level with proven nanotechnology, but let's start with examining the challenge at hand.

Manufacturing – yes even for clean technologies such as solar – presents its own challenges in how we comprehend water efficiency. In producing steel, for example, enormous volumes of water are used as a coolant for equipment, furnaces, and more. To put this in perspective, approximately 75,000 gallons of water are required to produce one ton of steel.¹ Solar manufacturers also using water as a coolant face similar challenges, as cooling towers withdraw between 600 and 650 gallons of water per megawatt-hour of electricity produced.²

In addition to cooling, water is used as a lubricant, solvent, as a seal, for pollution control, for cleaning, steam generation, and more. This taxes natural resources as well as reservoirs, which impacts availability and cost – simple economics. Most modern manufacturing processes employ some form of water filtration or recycling to improve efficiencies, and yet we have not reached our full potential. In fact, we are far from it.

Manufacturing processes for many industries have been in place for decades and even centuries. The truth is, the underlying architecture of the processes for manufacturing steel, solar, and other products and materials are from a time when businesses, governments, and residents perceived our precious natural resources were endless. Times have changed. For this reason, we must challenge ourselves to solve the Water-Energy Nexus. This popular phrase is best defined as the relationship between water and energy – two mutually dependent resources – incorporating cost, storage, production, and other facets of supporting each other's role in day-to-day human activities such as manufacturing. It has long been an axiom that it takes a lot of water to make electricity, and a lot of electricity to provide water or, simply put, "water needs electricity needs water." Nine U.S. states recognize the nexus between water and energy.³

Breaking the Nexus
In 2012, severe droughts struck the United States, placing significant constraints on power plants and other energy producers. The lack of energy resulted in difficulty treating, delivering, and pumping water.

Older processes are one reason that key supply and demand-like principles have to be faced, as the world is using more energy and more water. The other reason, according to the United Nations Department of Economic and Social Affairs, is the world's population (at about 7 billion people in 2014), which is expected to grow to 11 billion people by 2100.

It will take fundamental changes in how we view the Water-Energy Nexus, as well as manufacturing and material production, to alter decades-old processes used today in manufacturing plants across all industries worldwide relying on a perceived "never ending" supply of water. The good news is there are proven technologies emerging today presenting the opportunity to "break the Nexus," solving a potential crisis.

One opportunity to break the Nexus is using proven nanotechnology materials in a supporting nanomaterial-based architecture to clean post-production contaminated water to high levels of purity for safe and immediate reuse, rather than drawing more potable water. In this process, a water molecule is separated from the contaminated waste stream by a hermetic membrane using nanotechnology, producing product water which is "parts per billion" clean. As an example, a water filtration system at a steel manufacturing plant could be improved through deploying this nanomaterial and an eco-friendly architecture allowing water molecules from the contaminated water stream to transfer through this solid "smart" membrane specifically built to transfer largely clean water molecules. The ultra-clean water produced is then pumped back to the beginning of the production process.

This benefits industry and the environment in five ways:

1) Improving the quality of the product water allowing re-use instead of drawing more water;
2) Requiring less "new" energy, no "pre" or "post" process treatment of water, and no biofouling of the nanomaterial membrane;
3) Offering less environmental impact of discharging of the effluents collected using the nanomaterial based architecture;
4) Lowering capital and operating expense budgets needed to construct and operate nanotechnology water cleaning systems over traditional water cleaning systems
5) In some applications, providing cleaner product water existing products can be improved, or a new generation of product is enabled.

With a better overall contaminated wastewater cleaning process, a manufacturing plant could increase production while reducing costs, as well as wear and tear to the entire system. The produced reused water improves energy efficiency (lower cost and lower emissions) while breaking the Nexus – the previously inextricable link of water-needing electricity-needing water.

Nanotechnology has already begun making strides in addressing air quality and the efficiencies within heating and cooling air, such as within an HVAC system. Nanotechnology facilitates better management of latent and sensible heat in the fresh air supply before it is presented to the HVAC system, reducing the energy and the overall size of the HVAC equipment needed to do so. The U.S. Department of Energy, as well as companies, industrial complexes, and homes worldwide, has already implemented systems that improve indoor air quality while reducing costs and the wear and tear placed upon systems, particularly in old buildings.

We need to start examining the processes within Water-Energy Nexus the same way we are examining HVAC efficiencies: at the molecular level, using nanotechnology. The technology exists, as does the innovation, but what comes next requires a change in thinking and focus. Rather than challenging legislation and next-generation technology, actively address the concepts and newer products available today to begin the transition to a better-managed water resource for more efficient manufacturing.

Tim Tangredi is the CEO of Dais Analytic, a nanotechnology business producing a versatile family of membrane materials - called Aqualyte - focusing on evolutionary or disruptive air, energy and water applications. The company is based in Odessa, Fla. Visit www.daisanalytic.com for more information.

References
1. http://www1.eere.energy.gov/manufacturing/resources/steel/pdfs/water_use_rpt.pdf
2. http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-solar-power.html#.VVYcg9NViko
3. http://www.ncsl.org/research/environment-and-natural-resources/overviewofthewaterenergynexusintheus.aspx