Tank linings in the age of hydraulic fracturing
The advent of hydraulic fracturing has brought with it rapid economic growth and the previously undreamed of promise of energy independence for the United States. It has also completely changed the way the storage and transport of crude oil is approached.
Most owners of crude oil storage tanks, and the railroad tank cars that transport it, have recognized that fracking introduced many aggressive chemical components to the crude oil that previously got along pretty well with steel. Those that haven’t come to this realization find themselves at an increased risk for the sort of corrosion and pitting of storage tanks and tank cars that invite spills and significant environmental degradation.
Corrosion is the result of oxidation, which can’t occur except in the presence of oxygen and water. With traditional methods of oil extraction, some water was present in the crude oil, but usually in trace amounts and suspended in the oil where no oxygen was able to reach it.
As a result, for the vast majority of the time humans have been extracting crude oil from the earth, the storage tanks and transport vessels used to move it did not need to be lined with protective coatings. Storage tank owners could save money by not lining their tanks, with minimal risk of corrosive damage ever being a problem. To this day, it’s not unheard of to encounter companies still requesting that railcar manufacturers not line the inside of their cars.
Fracking has forced a change. Because drastically more water is used in the process of hydraulic fracturing, greater care needs to be taken to protect against corrosion. While transporting oil obtained by fracking, water and oxygen are both abundant, meaning corrosion is once again on the list of concerns for owners of storage tanks and railroad tank cars.
Not just the hotspots
Storage and transport of crude oil obtained by fracking is not just a concern for owners operating near traditional hotspots of extraction like Texas, the Dakotas and the Gulf Coast. Storage tanks are commonplace across the United States, holding newly extracted crude as it makes its way to refineries, where still more storage tanks hold it while the crude waits to be refined.
Given the current scale of fracking operations across the United States, if only ten percent of owners have not upgraded their tank linings to address this reality, there are an enormous amount of storage tanks vulnerable to pitting, corrosion and leaks.
Crude’s journey, too, has prompted concerns over the safety of transporting by rail. Some estimate that over 1 million barrels of oil are being extracted per day, and that 9 million barrels are riding the rails at any given moment. A standard railroad tank car can hold about 740 barrels.
If railcar owners want to help protect against legal action, there’s no reason the latest railcar linings shouldn’t be a part of that strategy. As a part of stricter regulatory legislation that is in the works, there should be at least some attention paid to minimum standards for railcar linings.
And then there’s the water
Fracking is a water intensive enterprise. By some estimates, somewhere between 70 billion and 140 billion gallons per year are required. Some are searching for a process to recycle this “frack water,” while others believe it’s best disposed of by pumping it into deep underground wells.
Whatever solution emerges, storage and transport of this byproduct will become an increasing concern for as long as fracking keeps up its current pace. This presents a problem. The chemical blend used in frack water is regarded as proprietary by the companies who use it.
Without knowing exactly what they’re protecting against, coatings manufacturers can’t stand by the tank linings they supply to protect assets. Certain variables make it more difficult to predict which products will be effective. If the byproduct still contains rock debris or other abrasives, for instance, an additive such as flake glass may lead to better performance.
Without knowing the exact composition of the substance these tanks are holding, coatings manufacturers cannot guarantee a given product will provide adequate protection. Companies in charge of storing and transporting this wastewater should therefore be closely investigating the tank linings they use, making sure they’re up to the task.
Tank linings systems guide
We want to simplify the process of selecting linings for both storage tanks and railroad tank cars. To do so, we’ve put together a guide complete with system selection guides, chemical resistance charts, data sheets, case studies and more. You can download it by clicking the link below.