The Challenge Planned Brackish Water Reverse Osmosis (BWRO) facility facing significant drop-off in water quality.
The City of North Point, Florida built a new brackish water reverse osmosis (BWRO) facility capable of producing 2.0 MGD of potable water by treating raw water from local wells with a Total Dissolved Solids (TDS) level of about 3,500 mg/L. However, the facility needed a flexible design because the conditions are expected to change over time. Nearby wells are degrading and the City anticipates that the raw water quality will degrade over time; historical data predicts salinity could increase by as much as 370% in the first 10 years of operations. The facility has two reverse osmosis (RO) skids, each capable of producing 1.0 MGD, which are designed to expand to produce 2.5 MGD each as demand for water rises. This wide range of operating conditions presented a significant design challenge.
The Innovation Solution The US’ First Installation of a BWRO PX® Pressure Exchanger®
Clean drinking water is fundamental to all life. As 2015 marks the end of the United Nations’ International Decade of Action recognizing water and sanitation as a basic human right, it also marks the beginning of a new era of water supply and usage across the state of California.
Since a statewide drought began four years ago, California lawmakers have struggled to find rainfall-independent solutions. This is not the first time California has turned to desalination as part of a larger plan to tackle decreasing water levels and drought conditions. The multiple-year drought in the 1980s led to the construction and opening of the Charles E. Meyer Desalination Plant in Santa Barbara. When rainfall returned just three months after the plant opened, the facility was mothballed. Forward-thinking experts kept up plant maintenance in the meantime, knowing it would not be the last time such measures would be considered or implemented.
There are also costs and other types of resource usage issues to consider. For instance, much of Southern California’s drinking water travels hundreds of miles from its origin in the Colorado River, transported using a massive and expensive aqueduct and conveyance system. With this current drought comes an opportunity to revisit tabled solutions and better prepare future plans to make desalination part of a larger framework to continue to keep California watered.
Desalination is not a silver bullet. But technology has improved the process and subsequently lowered the cost. Stuart White, director of the Institute for Sustainable Futures in Sydney, Australia, has called the need to plan for future plants “desalination readiness.” In Australia, as in many other arid, desert-like parts of the world, desalination has become a necessary and useful part of a plan to increase water resiliency and drought preparedness. The capacity of large desalination plants is quantified by how many millions of gallons of water per day (MGD) the plant produces, with Sorek, the world’s largest seawater reverse osmosis plant located south of Tel Aviv, producing 165 MGD. The largest desalination plant using membrane technology, which typically uses energy recovery devices such as the PX Pressure Exchanger, is Magtaa in Algeria, with a capacity of 132 MGD.
In the following pages, we’ll consider the success stories of desalination in California coastal cities, in Israel, and in Perth, where desalination helped pull the Australian city back from the brink of disaster during a decades-long drought. We’ll also look at other examples that circle the globe. Spain recycles 17 percent of its effluent, the second highest percentage worldwide after Israel, which treats 86 percent of its wastewater and irrigates more than half its crops with treated effluent. Domestically, states with desert climates, including Texas, are considering adding desalination plants to their resource management portfolio as a way to stay ahead of disaster and move ahead with progressive, affordable technological solutions to an age-old problem.
Location: Tortola Island, British Virgin Islands Project: Biwater Tortola
Product Configuration: PX Pressure Exchanger and AquaBold high pressure pump
Capacity: 10,400 m³/ day
The Challenge: British Virgin island dependent on reliable freshwater for GDP growth
Tortola is the largest British Virgin island in the Lesser Antilles with an approximate population of 24,000 residents. 92% of its Gross Domestic Product (GDP) comes from tourism where close to one million people visit the island every year. As with many island nations without natural aquifers, Tortola must produce all of its drinking water and demand is constantly high. Historically the island has supplied fresh water to residents and visitors through seawater reverse osmosis desalination, but current facilities in operation are deteriorating and this is having a deleterious effect on the island’s environment and marine life. In order to meet the island’s growing demand for fresh water supply, Biwater was contracted to design a new, environmentally-sound desalination facility to provide high-quality fresh water to the island alongside wastewater treatment facilities.
The Innovation Solution: The PowerPlay for faster time to market with superior energy savings
Biwater selected Energy Recovery’s PowerPlay integrated solution: PX Pressure Exchanger® 220 and the AquaBold high pressure pump. In island nations such as Tortola where power costs are high, Biwater chose the PX energy recovery device because it has the fastest payback than any other ERD in the market and allows the company to focus on delivering the highest quality water at the lowest price to the end user. In summary, by choosing the PX and AquaBold PowerPlay solution, Biwater is able to streamline the complex process of moving the Tortola plant from concept to operation. By combining the PX and the AquaBold, the Biwater Tortola project will enjoy faster deployment, longer life, and greater uptime.
The Result: Highest quality water for island’s biggest industry
The Biwater Tortola plant will be able to supply residents and tourists with highquality, affordable potable water. When operating at full capacity, the Tortola plant will produce 10,400m3 of treated water per day, and with Energy Recovery’s PowerPlay solution, the energy saved will be an estimated 9 million kWh per year – or the equivalent to taking 1,300 cars off the road. In addition to the new desalination facility, Biwater is also providing wastewater treatment facilities that will help better protect marine life in the vicinity. Once the desalination plant is online, the facility will boast the highest efficiencies possible with the Energy Recovery PowerPlay.
Today, energy costs represent one half of the total cost of oil & gas processing. By harnessing the wasted energy in your high-pressure environment, we can help you slash that cost by 25%, while significantly lowering your carbon footprint. And we have proof. Read all about it in this free white paper available for download now.
Six years ago, we installed our energy-saving IsoBoost Technology at the 50 million cubic-foot-a-day Jackalope Amine Gas Processing Plant in Hebronville, Texas. Since then, our solution has:
Ran for six straight years, requiring virtually no maintenance
Reduced emissions at the plant a total of 14.4 million pounds of CO₂
Saved the small plant $155,000/year, or close to a $1 million in power savings.
Don’t waste another year’s worth of profits. Discover how Energy Recovery can help you today!