With regulations constantly evolving, industries must prioritize water resilience for sustainable operations. This article explores the critical aspects of water management, treatment, and reuse, emphasizing the importance of integrating these processes into a comprehensive water resilience plan. By examining various water sources, treatment methods, and the challenges posed by climate change, the article provides insights into optimizing water use while minimizing environmental impact and operational costs.
Discussions about water as an industry resource to be protected and preserved are often conducted with an emotional rather than a technical approach.
Though well-intentioned, this misses an important opportunity to discuss water treatment and reuse as part of a larger water resilience plan.
No matter the type of industry, production units require water. Some sectors require more water than others, but the need for water is always present. However, not every process requires the same quality of water. Specific process needs range from ultrapure to good to medium quality water; in several cases the largest amount of water needed (i.e. for cooling purposes) can be of “medium quality”. Purifying water to only the quality required is foundationally important to increase water resilience and reduce CO2 emissions which could be generated if a “too high quality” is produced and used where is not needed.
Businesses must plan their water need in advance, which is a complex process pressured by different, occasionally conflicting, drivers: operational efficiency, corporate sustainability, and the potential environmental impact on aquifers and water courses. Combined with ongoing societal changes, such as improved production methods, new legislative context, and more stringent regulatory standards, companies can end up designing, installing, and managing multiple concurrent, but uncoordinated water systems instead of a seamless whole.
Starting with mass and energy balances is a holistic, efficient, and sustainable approach to water planning. As water is an energy carrier and all production and water treatment systems use energy, this comprehensive approach works whether designing a system from scratch or intervening in an existing system.
Water sources and competition
Part of your water plan requires understanding the impact your water use will have on the surrounding environment. Understanding where your water comes from is the first step. Industry takes water from many different sources: aquifers, surface watercourses, reuse water, brackish, sea water, and others. Depending on the type of water available, drinking or agricultural water may be in direct competition with industry for the best or most readily available water source.
The better the source water quality, the less effort is needed to transform it into water suitable for industrial needs but the greater the competition for its use. A clear mountain spring can be used much more easily than water from a muddy river. And drinking water and agricultural water generally take precedence over industry. Industry often chooses to use less valuable water, which may require more treatment, but reduces local competition and ultimately minimizes the risk of water scarcity.
Water treatment: how much is too much?
Lower quality water requires treatment both before and after use. Many industrial sectors require water for cooling, steam, and other processes. But water is not simply water: it is H2O plus dissolved salts, organics, and solids. Thus, treatment of water at the source must eliminate or reduce whatever is not H2O according to sector-specific standards, at a volume that doesn’t waste effort by preparing water too good for the intended use.
During use, production transfers non-H20 substances to the water, such as metals, organics, salts, etc. The exact additives and ratios differ by industry. Wastewater from an oil refinery is different from that of a food and beverage company, for example, and thus must be treated differently before it can be returned to surface water.
Each water or wastewater treatment requires energy. Overtreating water wastes energy. Designing the proper water and wastewater treatment for your business minimizes both your CO2 footprint and the associated costs.
Reducing treatment by-products
Every water treatment process generates by-products. Selecting the most efficient treatment method can minimize by-products like sludge, brine concentrates, and other waste, but not eliminate them completely. Proper by-product management and disposal requires a commitment to regulatory compliance and a focus on reducing both the overall environmental impact and industrial costs.
An important tactic is to reuse wastewater generated from specific processes, both intermediate and at the end of the purification cycle. Not only does reusing wastewater significantly decrease dependence on the primary water source, but by incorporating water modeling techniques, such as mass and energy balances on wastewater around the entire water circuit, you can best determine how and where reuse is most appropriate and sustainable.
Resilient to the challenges
In addition to the risk of water scarcity due to climate change, industries risk losing water allocation. That is, the possibility of the loss of operating permits due to inadequate water resource management. The result means adapting to lower quality water, which will then may require treatment of both source water and wastewater, making the process even more costly and less sustainable.
Water resilience concerns the health of the primary sources more. A proper redundancy treatment unit also increases resilience, as does treating water only to the quality that is truly needed. The technologies in advanced treatment systems produce and maintain the required quality of water with minimal CO2 impact.
Methods to store and manage water reserves are another facet of resilience. Function, rather than size, is the concern. Construction is the largest contributor to CO2 emissions, so the smaller the storage unit, the better. A system which takes water from different sources, such as an aquifer and a water re-use system, which then sends it to smaller common storage before distribution - aligns with a CO2 minimization strategy, adding resilience on more than one axis.
Keep the flow moving
A lack of water negatively impacts production; in fact, it can bring production to a standstill. Thus, it is critical to design some measure of redundancy into the equipment, process, and necessary systems.
To be future ready, a water/wastewater treatment plant must avoid building a plant too big for its needs, while adding some flexibility of structure to adapt the system to evolving requirements. Modularity is the key to water/wastewater treatment plant design, allowing for potential changes in plant architecture or future industry needs. Today, industries can work with highly skilled water treatment experts to build resilient water reuse strategies.
In addition to the applicable water treatment process, systems, and technologies, water treatment experts must also understand the needs of the relevant industrial sector. For example, water management and treatment is considerably different in the energy sector than in pharmaceutical or food & beverage, and in all cases, it is separate from the potabilization, and sewage treatment carried out by municipal companies.
Industries need water professionals who follow the entire water cycle and treatment chain or risk embarking on a series of uncoordinated projects which may each solve one specific problem but not the whole.
An experienced water/wastewater process technologist will guide the client to the optimal choice of system design and support both implementation and management, helping them navigate the changing regulatory landscape and strategize for current and future resilience.
Key Takeaways
- Water treatment and reuse need to be part of the larger water resilience plan.
- All industries require water for production. The amounts vary by sector, but the need does not.
- Not every process requires the highest quality water. Overtreating water to an unnecessarily high quality is a waste of energy and resources.
- The by-products of water treatment can be minimized but not eliminated.
- Companies can reduce their carbon footprint by reducing over-treatment of water and using appropriately sized water treatment units as well as storage.
- A future-ready approach is essential, allowing the water/wastewater system to be modular and adaptable to changing production needs as well as boundary conditions (legislation, water scarcity, type of production) across the years
- In addition to water treatment processes, systems, and technologies, water experts must understand the specific needs and requirements of the industry involved.