Produced water reuse can be a valuable strategy for operators because lowering their water footprint helps promote sustainability. With oil production rising in the Permian, companies are producing more water in relatively small areas, leading to heavy investments in water infrastructure and water recycling. In a presentation held at the Permian Basin Water in Energy Conference, Tyler Hussey, a water resource engineer at Apache Corp., examined the process companies go through when deciding on a proper recycling system for their operations.
Last year, recycled produced water made up more than 40% of Apache’s frac water usage in the Midland Basin. Hussey said that the company’s goal this year is to raise that total closer to 50%, and that his personal goal is to raise it as high as possible. However, there are several additional factors that influence the scope and scale of recycling. Apart from technological advances, Hussey said that surface use constraints can be a roadblock to effective planning. Oftentimes operators do not have significant amounts of continuous acreage, making large-scale projects more difficult to plan.
“Typically you don’t own your own land, so you’re dealing with the owners of the land, you’re dealing with different people. Everyone has different motivations, and it can be a challenge logistically if you’re trying to put in a cross-country pipeline, or if you’re trying to put in a recycling facility with a pretty big footprint,” Hussey said.
In addition, Hussey said the proximity and intensity of infrastructure development can have an impact on recycling programs.
“Frac crews are moving. You don’t have the same frac crews in one area for months and months at a time, generally, and that can make it difficult to get water from Point A to Point B,” he said.
Another factor is the gradual transition from gelled oil-based fracturing fluids to slickwater fracturing fluids for most Permian operations. Hussey said slickwater fracs require more water at a higher flowrate with higher pressures to carry proppant as opposed to gels, which has increased the amount of water used at each well.
Pad drilling is also a big reason why operators are using more water. Hussey said the practice of drilling multiple horizontal wells from centralized well pads can be valuable for reducing an operator’s surface footprint at a site; multiple landing zones reduce the need for building new pads for each well. However, he said pad drilling increases daily water usage because an operator can frac more wells in a shorter period of time.
In an active area, Hussey said frac hits—where the drilling and fracturing of new wells affects the production of older adjacent wells—influence decision making. As production decreases from an adjacent well, operators may pump out an excess amount of produced water. Hussey said that, with the number of wells being drilled in the Midland Basin, companies have to account for the potential strain this excess water provides.
“If you hit a lot of wells, that could definitely increase the amount of water you’ll see flowing back from those wells,” Hussey said. “Now the facility guys are getting a lot more water than they designed for, and you can have some constraints on your facilities.”