A gun-barrel separator (or wash tank) is a storage tank which has been modified to allow continuous separation of an incoming oil and water mixture. Wash tanks are usually used in remote locations near the well site to separate oil from water that also comes into the well from the reservoir.
A wash tank is a system that works solely on specific gravity. The height of the gunbarrel overflow dictates the interface level in the tank. Water drains only when the following condition exists:
(H1 – height of oil in the wash tank x SG* OIL) + (H2 – height of the water in the wash tank x SG* WATER) > (H3 – height of the water in the riser pipe x SG* WATER) *SG = specific gravity
This is how it works; the level of oil and water in the wash tank has to be greater than the level of water in the gunbarrel (or rather the level of the overflow) in order to allow water to drain from the wash tank through the gunbarrel and out of the overflow.
As more oil accumulates in the wash tank, H1 will increase and the total of H1 and H2 will increase. This will result in oil overflowing to the oil storage tank. To explain it simply, the wash tank allows for the incoming oil-water mixture to accumulate in the top chamber, slowly flowing into the second chamber where the separation of the two substances begins due to the difference in specific gravity. Because the oil has a lower density than water it ‘floats’ on top, and as the oil-water mixture begins to accumulate it pushes the oil that was ‘floating on top’ into an oil storage tank. So now that we’ve covered the basics, let’s get into the gunbarrel separator model that our engineering team has been working on.
With blue-prints in hand, our ESD team headed over to Okanagan College Kelowna campus to meet with the Engineering Faculty to inspect their first prototype, and for a first prototype it worked great!
The prototype did exactly as expected and we found only minor tweaks that would improve the model and ensure the cleanup process was efficient. As you can see in the pictures the current oil storage tank is an open bucket, which you can only imagine how enthused our trainers would be to tote buckets around for training courses.
Pictured below are Brian and Mark, along with Reg from the College inspecting the first prototype and discussing the modifications that are to be made for an even more efficient second model. Stay tuned to see the finished product!
Mark Dixon and Brian Hillaby inspecting the first prototype
The first prototype in action!
What else have we been working on this summer? read our summer series part 2 HERE