Chemicals, Environment, Facilities, Food and Beverage, Industrial, Metals and Mining, Oil and Gas, Power, Water Reuse, Sustainability
Applying Reclaimed Water for Industrial Uses
Reclaimed water is increasing its value to industries—from oil and gas, to metals and mining, and food and beverage—and corporations are harnessing the availability of reclaimed effluent to support their total water needs. For years, treated effluents from municipal and industrial treatment plants have been discharged to water bodies. Municipal reclaimed water has been used for other beneficial uses for more than 50 years, but reclaimed water from industrial sources has recently become a new resource to meet growing water demands. Capable of meeting diverse water quality standards to support industrial and commercial process demands, irrigation and other non-potable uses, reclaimed water is a sustainable solution for industries to consider and implement as a part of their water use and management strategy.
Reclaimed water provides a reliable water source, especially in water scarce areas, and promotes sustainable operations while reducing environmental footprint. It is a cost-effective use of a resource that financially benefits the industry and community. In the United States, a great majority (56.8 percent) of reclaimed water is used for landscape or agricultural irrigation. Reclaimed water is also used for aquifer recharge (12.8 percent) and industrial uses (10.0 percent). While industrial reuse is a small percentage of the overall market, the demand for water reuse is growing. If you haven’t considered the local availability and potential uses of reclaimed water, are you missing an opportunity to secure a future water supply and reduce your total water costs?
The Need for Reclaimed Water
There are three key drivers for water reuse:
- Water scarcity and urbanization. This is probably one of the first drivers that come to mind when thinking of water reuse, especially in typically arid regions such as the U.S. southwest or Middle East. However, it is becoming more of a driver in areas not traditionally water scarce, such as Tennessee, Georgia, northern Virginia and Massachusetts, as water resources are becoming fully allocated even in regions with high annual rainfall. Water scarcity can also be a driver in areas that locally rely on one specific aquifer or reservoir. Adding reclaimed water to an industry supply portfolio can increase reliability of water supply for critical operations.
- Energy and sustainability. Some advanced applications of water reuse use energy intensive technologies, such as reverse osmosis (RO). However, while RO can require significant energy, in some cases the RO process may require less energy than alternatives, such as brackish groundwater or seawater desalination or pumping water from a great distance. Thus, it is important to think of water reuse in terms of life cycle analysis of that water balance. Water reuse can also support an overall sustainability strategy, such as through LEED®-certified facilities.
- Environmental protection. Reclaimed water is being used to replenish natural and constructed river and wetland systems that have become water stressed in regions where there is competition for water. Likewise, water reclamation is being used as an alternative to discharging treated wastewater to ocean outfalls or surface water bodies to protect critical ecosystems from nutrient loading. In fact, phosphorus and nitrogen, which may have to be otherwise removed from wastewater prior to discharge, may act instead as beneficial fertilizer if reclaimed water is used for landscape irrigation or agriculture.
Applying Reuse for Industrial Benefit
Availability is a very large component of water supply, and supplies need to be reliable, energy efficient, and meet environmental and social benefits. It must be continuously available as interruptions can be disruptive to production. In some cases, municipalities have or are considering reservation of some reclaimed water supplies to be used as an economic incentive for industries to locate or remain in their community. Another advantage is that reclaimed water, whether produced and recycled onsite or purchased in a long-term contract from a utility, allows a secure supply for industry while allowing potable fresh water to be used first by the community.
Industries contemplating water reuse should first consider their water supply. Is it reliable? Are there rate increases in the future, both for water supply and wastewater discharge that may affect the bottom line? Is the supply adequate to meet current and future production needs? Is there something on the horizon that could limit water supply?
The first step in evaluating whether water reuse can play a role at a specific facility is understanding an operation’s water balance. Since each industrial facility has site-specific processes requiring various water qualities, the treatment required for each stream in a water balance will differ. For instance, there may be water streams that lend themselves well to being adapted to use reclaimed water. The next step is understanding the applicable regulations that apply to each facility. Finally, when evaluating water reuse, don’t forget to include major customers and the public in the decision-making process – the general public is becoming increasingly aware of challenges to water resources and potential solutions, including water reclamation. Tackling this issue can set a facility apart as being proactively engaged in a key social, economic and environmental issue. Remember that your employees are part of their community.
Industry in 2012 EPA Guidelines for Water Reuse
Recognizing the need for guidance on water reuse, the U.S. Environmental Protection Agency (EPA) developed comprehensive water reuse guidelines to support establishment of state regulations and guidelines. The EPA Guidelines for Water Reuse includes opportunities, challenges and trends in reuse; as well as a description of water reuse applications and treatment technologies to be safe and successful. The guidelines also illustrate a framework for water reuse programs, especially for implementers or regulators that are starting a new program.
For the 2012 update, the document outlines some of the traditional industries that apply water reuse such as pulp and paper, textile and cooling towers. It also describes expanding new applications in electronics and high technology, corporate and school campuses, process and boiler feed water, power, oil and gas, and food and beverage.
For example, reclaimed water is becoming an important supply for power plant and central energy plant cooling. University of Connecticut uses reclaimed water for cooling in their central energy plant and for boiler operations. San Antonio, Texas, uses reclaimed water (50,000 acre-feet/year) for power plant cooling and in central cooling plants serving downtown, the Alamodome, AT&T Spurs Center, and at Combined Base San Antonio, which serves the world’s largest military hospital. In the arid west, the Palo Verde Nuclear Generating Station 30 miles west of Phoenix, Ariz., uses 85,000 acre-feet per year of reclaimed water from a regional municipal plant in Phoenix. The West Basin Municipal Water District in Orange County, Calif., supplies reclaimed water for low- and high-pressure boilers to refineries such as Chevron in El Segundo, Exxon-Mobil in Torrance and BP in Carson.
Case studies are also provided for award-winning projects, like the Frito-Lay (PepsiCo) Casa Grande, Ariz. facility that internally treats industrial process water for reuse to a quality higher than the local potable water. Also featured is Coca-Cola’s Rainmaker project, implemented to provide in-plant beverage process water recovery systems for clean-in-place and bottle washing. Learn more by reading the EPA Guidelines For Water Reuse.