Odessa · Midland · Permian Basin tank types
Frac tank sizes and types for Permian jobs
When people around Odessa and Midland say "frac tank" they nearly always mean the 500-barrel steel tank on a rear axle that a winch truck drags onto location. The same yards often rent a few other shapes too. Here is what each one is and when it gets picked.
Closed-top steel frac tank, 500 bbl
- Holds
- 500 bbl, which is 21,000 US gallons (42 gallons to the barrel).
- Length
- About 43 ft on the two maker listings checked; some builds run to about 45 ft.
- Width
- 8.5 ft.
- Height
- 10 to 11 ft depending on the build.
- Empty weight
- About 29,500 lb.
- Steel and lining
- Listings describe 1/4-inch steel walls and an internal chemical-resistant coating.
- Floor
- V-bottom or round-bottom, so solids slide toward the drain and the tank empties more fully.
- Options seen
- Steam coils for heating fluid in winter, extra manifolds, stairs and walkways. Ask what the firm's fleet actually has.
Good for: frac water, flowback, produced water overflow, hydrotest water, recovered liquid after a spill. The closed roof keeps rain and dust out and holds in some vapor; ask about gas-tight hatches and venting if the fluid is sour or volatile.
Open-top tank
A steel box with no roof. Easier to dig out with a vac truck or backhoe, so it suits liquid carrying a lot of sand, mud or debris, and jobs where you need to watch the level by eye. Rain gets in, which counts against it for long storage.
Weir tank (sometimes called a settling or mud tank)
An open-top tank with internal walls, the weirs, that make the liquid pass over or under each one in turn. Heavy solids drop out in the first chambers and cleaner water spills on toward the outlet. Picked for drilling returns, dewatering an excavation, or anywhere you want to settle sand out before the water moves on. Ask for chamber count and outlet size if you have a pump in mind.
Poly tank
A polyethylene tank, usually far smaller than a 500 bbl steel tank. Polyethylene does not rust and resists many acids and caustics, so poly tanks turn up for chemical storage, acid jobs or small water needs. Check the firm's chemical compatibility chart for your fluid; poly has temperature and pressure limits steel does not.
Picking between them
| Job | Usual first choice | Worth asking about |
|---|---|---|
| Frac water at the pad | Closed steel, 500 bbl | Manifold layout for your pumps |
| Flowback with sand | Closed steel or open-top | Washout charge, sand removal |
| Produced water overflow | Closed steel | Lining, gas-tight hatches, containment |
| Excavation dewatering | Weir tank | Number of chambers, filter options |
| Acid or chemical | Poly or lined steel | Compatibility with your exact chemical |