Oil and Recycled Water Do Mix

Friday, February 29, 2008 in Water Efficiency

By Mark Saunders

When George W. Bush announced to the world in his 2006 State of the Union Address “America is addicted to oil,” the president (a former oil man himself) was not joking. According to the Energy Information Administration (a branch of the US Department of Energy), in 2006, the US consumed 20.6 million barrels of oil every day. At 42 gallons to the barrel, that’s 865 million gallons of oil a day. To put these colossal numbers in perspective, we’re talking about Americans using the volume of oil contained in 14 supertankers the size of the Exxon Valdez, every day.

Do the simple math, and you come up with a national consumption rate of 315 billion gallons of oil per year. For the sake of comparison, the distance between the Sun and Pluto is a mere 3.7 billion miles. Part of what is so difficult to grasp about America’s oil consumption, is that it’s hard to get your mind around the idea that there is that much oil on the planet, let alone that much being consumed by one nation.

To process this enormous amount of petroleum, refineries all across the country are working around the clock to keep up with our seemingly insatiable demand for gasoline, jet fuel, heating oil, lubricants, paraffin, asphalt, and a host of other products made from the distillation of crude oil. However, it is interesting to note that there are a scant 149 petroleum refineries left in the US, less than half the number that existed in 1981—and, gasoline consumption has risen by 45% during those ensuing 27 years. An equally puzzling fact, especially in light of price of a gallon of regular unleaded cresting $3 per gallon and the cost of a barrel of crude oil approaching $100, is that no new refinery has been built in this country in more than 30 years. The next refinery scheduled for construction—the Arizona Clean Fuels Yuma plant—won’t be online until sometime in 2011.

America is in a precarious energy position: We are consuming record amounts of petroleum products to drive our cars, heat our homes, and keep the wheels of commerce turning, and yet we are not upgrading our gasoline production facilities and our consumption continues to rise unchecked.

Mind-Boggling Information

In it’s most elementary form, the process of refining petroleum is much like the distillation columns used in high school chemistry labs: energy (in the form of heat) is applied to the crude oil in the “boiler,” and the evaporation and condensation of the various compounds in the oil are separated in a cooling tower by their boiling points and specific gravity (For a primer on what happens at an oil refinery, visit www.howstuffworks.com/oil-refining.htm). In a secondary school chem lab, the distillation tubes (read: cooling tower) are then either air-cooled or do not require massive amounts of water to keep the entire process from overheating. At an oil refinery, however, the boiler temperatures often exceed 1,000ºF, which would eventually melt the building where the boiler is housed, if it were not properly cooled.

In addition to water used, in keeping refinery boilers operating comfortably, cooling towers (where the fractional distillate condenses to form gasoline, jet fuel, and other compounds) also require huge amounts of water—as do cogeneration facilities that transform unwanted petroleum byproducts into electricity by creating steam to turn a turbine.

So, it should come as no surprise that as a nation of oil addicts, we are also hooked on all the attendant processes required to deliver the precious commodity that makes our modern, energy-dependent lifestyles possible. In other words, we are also addicted to inexpensive, readily available water.

Denis Kurt, Lead Process Engineer at the British Petroleum (BP) refinery in Carson, CA (the 15th largest refinery in the country), which refines 275,000 barrels (11.34 million gallons) of crude oil per day, says his plant continually uses 9,000 gallons of water per minute,. That’s approximately 13 million gallons of water a day (just slightly less than 40 acre-feet of water per day). To put those numbers in a friendlier framework, BP’s Carson plant uses more than 19 Olympic-sized swimming pools worth of water every day.

According to Rod Spackman, manager of government and public affairs at Chevron’s refinery in El Segundo, CA (the 16th largest refinery in the country, 13 miles northwest of BP’s Carson facility), his plant processes 260,000 barrels of oil (approximately 11 million gallons) every day, using 10 million gallons of water a day in the process.

The take-away from these two examples is that on a gallon-to-gallon basis, it takes roughly as much water as oil to produce the lifeblood of our nation’s economy. In almost all refineries, the process of refining crude oil requires at least as much water than oil—sometimes twice as much. Despite the fact that potable water is a lot cheaper than crude oil, it is no less scarce.

Adding Climate Change

Al Gore didn’t win a Nobel Prize and an Academy Award for an interesting idea. Whether you call it “global warming” or “climate change,” one thing is for certain: a majority of scientists no longer consider what’s happening to North America’s climate merely a cyclic event. The North East, the South East, and the South West are all experiencing serious drought conditions. The snow pack in the Sierra Nevada and Rocky Mountains ranges are at record low numbers. The water level on Lake Mead (just above the Hoover Dam on the Colorado River) is at an all-time historic low since the dam was built in 1935 (100 feet below its high point).

In “The Future is Drying Up,” New York Times Magazine writer Jon Gertner writes about the perfect drought: a confluence of a “Western drought caused by climactic variation and a drought caused by global warming could arrive at the same time.” Or, as Gertner put it, “perhaps they already have.”

Dwindling water resources across the country highlight the need to address our water consumption habits. And oil refineries are one of the, if not the, largest industrial consumers.

The South Bay area of Los Angeles (L.A.), CA, home to a half dozen major oil refineries, receives only 12 inches of rain per year; however, 2007 was one of the driest years on record for southern California. As of December 1, 2007, L.A. had received less than four inches of rain for the year. That kind of drought, which was preceded by the second wettest year in L.A. history in 2005, has wreaked havoc on the water providers, agriculture, and created the arid incubator for the October–November 2007 fires, that swept southern California, from Santa Barbara to the Mexican border.

Seeing the Big Picture

The fact that the population of L.A. extends beyond the 200,000 people who could be reasonably supported on local water sources, is a testimony to the political power, engineering skill, and deviousness of Robert Mulholland and Fred Eaton, who bought, borrowed, and stole water from the Owens River, and set the stage for the Colorado River, as well as the Sacramento/San Joaquin Delta projects. The Los Angeles Department of Water and Power’s acquisitions have allowed the city (and surrounding communities) to blossom into a megalopolis of 10 million people.

Photo: Chevron Corporation
Potable water is a lot cheaper than crude oil, but is no less scarce.

Even with water brought in from hundreds of miles away, there is a resource dependent carrying capacity that limits the number of people who that can live in an arid desert—as well as the amount of industry the region can support.

In the early 1990s, southern California was in the middle of an eight-year drought that turned the region into a hot, yellow hell, and stretched water resources well past the critical stage. During this time, it became apparent to the powers that be at the West Basin Municipal Water District (which serves approximately 900,000 customers from Malibu, south to the Palos Verdes Peninsula and several miles inland), that continuing to provide oil refineries with potable water was a misallocation of southern California’s most precious resource. By 1995, West Basin’s program, to provide oil refineries in their service area with a reliable stream of high-quality recycled water, was up-and-running.

According to Kurt, the underlining reason for BP’s switch to recycled water is to procure long-term water supply that is not subject to the weather, climactic fluctuations, agriculture, or the 125 gallons per person, that Los Angelinos use in their homes each day.

“It’s pure sustainability—the most effective way to wean us off potable water,” he says. “There are no legal mandates from Sacramento. We’re doing it on our own terms, so we have a leg up when some legislation comes down the pike—which can lead to a lot of rough lessons.… When this refinery was first built (approximately 84 years ago), there was lots of inexpensive well water. So, the refinery was built around inexpensive well water. Obviously, the economics have undergone a paradigm shift, and all oil refineries in southern California are feeling a pinch in the water supply.

“Right now, recycled water is not completely reliable for maintenance purposes or in the event of an accident. So, we do have potable water back-ups. It could take us a week or two after a shutdown to get everything back up and running, so we have to have a reliable source of water.”

Frequent production interruptions would no doubt drive the cost of gasoline production through the roof—costs that would, ultimately, be reflected at the pump, and in the costs of virtually all goods and services that require transportation. With the price of a gallon of gasoline 70 cents higher than it was this time last year, fuel-related cost increases are something that no one wants to see.

The Process

The path of this water begins at city of Los Angeles’ Hyperion plant in El Segundo, which sends treated municipal effluent to West Basin Municipal Water District where they further treat the water (mostly gravity filtration) and bring it up to Title 22 (of the California Administrative Code) standards. This Title 22 water is used for industrial purposes, irrigation uses, duel-plumbed buildings, and other applications where potable water is not required. Instead of building one recycled-water treatment plant, and producing the quality and quantity to fit each end-user’s requirements, West Basin has built onsite Reverse Osmosis (RO) treatment plants for both Chevron and BP, that are maintained by the utility. So, the Title 22 water is pumped from West Basin to each refinery, where it is further processed by microfiltration, RO (first and second pass), and nitrification.

“They all pay for capital, and then there is an additional commodity charge for each acre-foot of water that they use,” says Wyatt Won, West Basin’s manager of operations. “It’s very similar to what a water retailer would do to their customer. They would charge a customer, householder, or whatever, so many dollars per one hundred cubic feet. We do the same thing, only we charge them per acre-foot, because of the quantities that they use, but, the idea is similar. There is a separate fixed charge to help recover the capital costs.”

For Chevron, those capital costs were between $30 and $40 million. “It’s intuitively backwards that recycled water should cost more,” says Kurt. “However, the unfortunate truth is that recycled water can, in some cases, be twice as expensive as utility water, because the plants that produce recycled water costs a lot of money and someone has to pay for it—and West Basin makes the end user pay. The per-gallon cost is lower than potable water, but the capital recovery cost is greater.”

The cost of recycled water mirrors the level of treatment. “For low-pressure boilers, what we call single-pass RO, the cost is somewhere around double that of Title 22 water,” says Won. “But, if have to run it through another RO pass because they need it even purer for higher-pressure boilers, then it runs more than double—maybe 100-130% more than the Title 22 water.”

Testing the Water

Cooling tower water does not require the same level of treatment as boiler feed water, because the lower operating temperatures in a cooling tower do not precipitate out as many of the minerals from the cooling water that cause scaling and fouling. So, it was a better place to begin the process of switching over to recycled water.

Photo: West Basin Water Utility
Reverse Osmosis pressure vessels provide boiler feedwater to Chevron.

“Exxon Mobile and Chevron were in the first bunch of customers we served,” says Won. “BP followed several years later. They all started with cooling tower water, and now all three are now using recycled water in their boilers.”

According to Kurt, no one wants to be a pioneer. The learning curve of change at the large industrial level is astronomically expensive, and requires extensive modification to the existing infrastructure.

“We started with cooling tower water, because it was the lowest risk.… It’s a challenge, but we’ve been successful,” he says. “We’ve been successful at working through all our issues [micro-bio, nutrients, slime, foam, and higher life forms]. And West Basin is every bit as committed to produce the water we need, as we are to using it—otherwise it wouldn’t work. We would be doomed without West Basin.”

For example, there were some problems at the beginning of 2006, when the water BP receives from West Basin changed abruptly. “The composition changed, and there were more contaminants, but, we have been able to resolve all problems to date,” Kurt says.

It is also important to note that, neither Chevron’s El Segundo plant, nor BP’s Carson Refinery, have switched entirely over to recycled water. A shift of this magnitude is too expensive to make all at once, and the changes create new challenges that are difficult to forecast accurately, even with experts from both sides working in concert.

Photo: West Basin Water Utility
Microfiltration units provide supplemental treatment to recycled water at BP.

According to Kurt, BP has gone from 20% recycled water in 2000, to 30-35% by 2007, and he expects to add another 60% by 2010-2015, with the addition of a larger recycled water facility onsite, that would produce 85-90% of the refinery’s needs.

There is also the question of backup. “We need appropriate back up systems of utility water, which is backed up by well water,” says Kurt. “That way your primary backup can fail and you’re OK; even your secondary backup can fail and you’re still OK.”

Environmental Footprint

As with all applications of new technology, be they an iphone, photovoltaic solar cells, or a recycled-water treatment plant, the early adopters shoulder a greater burden of the R&D costs and infrastructure changes.

That said, refineries, such as BP’s Carson Refinery and Chevron’s El Segundo facility (ExxonMobil’s Torrance Refinery is also one of West Basin’s recycled water customers, but they declined to be interviewed for this article), are paving the way for other industries, communities, and homeowners to use recycled water the way they currently use potable water.

“This was the right thing to do environmentally,” says Spackman. “Directly and indirectly through our heavy investment in RO technology and robust recycled water delivery system, we have helped lots of nearby residents and the local business community gain access to recycled water.”

The shift from potable to recycled water at these refineries, represents a dramatic step towards sustainable industry. True, the writing on the wall was clear enough: It wouldn’t be long before local, state, or federal legislation forced oil companies to reduce their water use; however, the move to recycled water at these refineries frees up tens of millions of gallons of fresh water every day. That’s water that can be utilized in new and innovative ways—or kept in reserve against the perfect drought.

 

Author’s Bio: Guest author Mark Saunders is a newspaper and magazine journalist based in Boulder, CO.

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