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As Texas looks at the water shortage, its leaders see the vast amount of wastewater in brown salted oil fields as a source of hope for future supply. There are not many other options.
But extracting clean water from this toxic slurry requires a huge amount of energy as Texas fights to keep up with the demand for the rapidly growing forces of build-outs of high-tech industry.
At current efficiency levels, treatment of all wastewater in Western Texas oil fields requires up to 26 gigawatts of electricity, exceeding the total production capacity of most states in the US. Even if operators achieve ambitious target efficiency, the Permian adds another 5 gigawatts, enough to run an average American home of around 5 million people.
“When we’re already stressed, it requires more force,” said Doug Robison, a longtime fracking executive whose new company, Natura Resources, will use small reactors to treat wastewater. “We need to bring water back to the state’s supply.”
Texas leaders are rushing to take away the water shortage as there are few new sources of water from the predicted water shortage by 2030. Meanwhile, wastewater volume in the Permian Basin of Texas, the country’s most productive oilfield, has skyrocketed to around 25 million barrels per day, or about 1 billion gallons per day, according to a survey that the state-funded research group will be presented later this month by the water consortium produced by the state-funded research group.
“It’s a lot of water,” said Shane Walker, director of the Texas Tech consortium. “Instead of just throwing it away, we could handle it and recover some.”
In January, the consortium signed a contract with Robison’s company Natura to develop a wastewater treatment facility that drives the heat in the next generation of molten salt nuclear reactors. Natura is one of two US companies with permission to build such a nuclear reactor, and is currently building its first unit at Abilene Christian University.
Meanwhile, Austin lawmakers have made billions of dollars of public funding available to projects that can handle oil field wastewater for agriculture and industry reuse. Skeptics argue that, given the cost, water purification probably won’t be a solution beyond the limit.
Wastewater from West Texas oil fields returning to the surface after hydraulic fractures or fracking is actually the dirtyest liquid ever for treatment. It is up to seven times the ocean and is full of unique drilling chemicals and naturally occurring hydrocarbons, ammonia and Earth’s radioactive elements. The most common method of using membrane filters cannot be processed, so companies are racing to apply other heat-based processes.
“Moderately, heat desalination requires more energy,” Walker said. “We’ll need more energy.”
That’s where Natura reactor designs come into play. The unit does not provide electricity and slowly evaporates the raw heat from the brine. This is easy as the molten salt reactor runs in F above 1,000 degrees Fahrenheit, and runs at much higher temperatures than traditional nuclear reactors.
The thermal process of desalination is not new, but due to large energy requirements, it is mostly applicable to small-scale processing within industrial work.
However, in the Permian Basin, the amount of problems is enormous. The oil wells can spit out three barrels of all the drainage in roughly 1 billion gallons of rough barrels each day. 5 feet of salt water is enough to cover the square miles. Almost all of that salt water is brought underground at high pressure for disposal, continuing to cause earthquakes, blowing up the surface and strengthening other environmental disasters.
Foreseeable future injections will continue. Large-scale solutions for water treatment remain apart for years and require a large build-out of energy supply, which is likely to include many new gas plants and wind and solar facilities before new reactors are deployed.
The current water treatment pilot project in the Permian Basin covers energy costs of 5-25 kilowatt hours per barrel treated wastewater.
It rivals 0.3 kilowatt hours per barrel to treat urban wastewater, compared to 1.3 kilowatt hours per barrel to remove seawater and 0.3 kilowatt hours per barrel to treat urban wastewater, according to Mike Hightower, director of the Water Research Consortium, which published research into the energy costs of water treatment.
1.055 billion gallons of drainage daily from the Texas side of the Permian Basin generates electricity needs of 5-26 gigawatts each, with the capacity of statewide generations in Idaho and Indiana, respectively.
“It’s expensive from an energy standpoint. It takes a lot of energy to treat this water,” Hightower said. “People need to think about costs and benefits, not just costs.”
More water, fewer earthquakes?
When Texas lawmakers devised a plan to expand the state’s water supply in 2023, they discovered that most of their sources were completely taken away. The lakes were fully allocated, the rivers were all spoken, and all aquifers were overpumped. They identified only three new potential water sources. Demineralized water, deep, salty groundwater, and treated oil field wastewater.
Hightower estimated that unlocking this new water supply for industrial projects, data centers or farms in the western world could potentially increase Texas by $10 billion in GDP.
At the same time, he said the environmental impact of wastewater injections can protect oil companies from potential production restrictions. In recent years, Texas officials have begun restricting injections in certain regions due to gas-sea saltwater earthquakes and strengthening geysers. The problem only gets worse, and future restrictions on wastewater treatment could ultimately limit oil production.
“Treatment is more expensive than disposal, but it’s essentially a risk management strategy. If seismic activity increases, you buy insurance that doesn’t need to cut production,” Hightower said. “We are reducing the need for disposal, so we can continue operations.”
Christine Guerrero, a carrier oil engineer in Houston, said companies would not choose to treat wastewater until it is lower than the injection process.
“It’s simply too expensive,” said Guerrero, an independent advisor who previously worked for Schlumberger, Chevron and Hess Corporation. “Unfortunately, there are too many companies in the industry who don’t do the right thing until they’re forced.”
The right thing to do was pay to treat the wastewater, not inject it all underground. However, she did not believe that the wastewater treatment project would cause a significant reduction in the amount injected daily. Even these treatment projects create waste that requires disposal.
The thermal process of desalination can produce about half the original volume in clean water and about 500 million gallons per day in the Permian basin. The remaining half is mainly salt. That’s because Guerrero’s calculations fill more than 6,900 rail cars per day. It will probably be injected back underground.
“Water cleaning probably won’t work there as more than a marginal solution,” said Guerrero, who has worked on oil and gas projects in 30 countries. “This gives this false sense of something coming that will stop all of this.”
The pilot project is underway
State leaders hope that public funds for the treatment produced will help to tilt the economy’s scale towards survival. In 2023, Congress approved a billion-dollar state water fund, including millions of millions for pilot projects in oil field wastewater treatment. Lawmakers are currently discussing laws that will allow more money to be used to build commercial-scale facilities.
Pilot projects are underway in the Permian Basin. One of the Texas Pacific water resources has begun construction of five megawatt test facilities that will treat up to 10,000 barrels of wastewater per day and spray it on a 100-acre plot near the town of Aura.
TPWR uses a thermal process that delicately freezes the delicate liquid so that the salt sinks to the bottom, then captures the top layer and filters it through the membrane, charcoal to remove remaining chemicals such as volatile organic compounds and ammonia.
The company aims to use between 5 kilowatts and 25 kilowatts per barrel of treated wastewater, said Robert Crane, executive vice president of TPWR.
“Heat treatment is within that range,” he said. “Everyone is trying to make it as low as possible.”
Crane said the TPWR is currently operating towards the high end of the range, but expects numbers to decrease as the process is polished and improved.
To power the facility, TPWR has signed up for a dedicated electric power generation, fueled by a nearby gas pipeline. The thermal desalination process of TPWR uses more energy to draw electricity to generate heat rather than directly extract heat.
However, Crain said the operation could dramatically reduce energy costs by incorporating the wasted heat left behind from the power plant’s gas reactors.
“Wash heat capture through the production of natural gas can drive it to a very economical range of costs,” Crane said.
So, Robison, CEO of Natura Resources, believes that a small nuclear reactor could work. The current design can generate 100 megawatts of electricity, but equivalent to 250 megawatts of thermal energy.
It is built at the location of a treatment facility and can provide its thermal energy directly to the thermal process.
“We’re not talking about electricity. We’re talking about heat right now,” Robison said. “A molten salt reactor that operates at such high temperatures actually adds new solutions that were previously unavailable.”
