I my previous post; I did not say increased volume, I was referring to increased velocity due to reduced viscosity.
Think of a pipeline as having a starting point and an end point. The pipeline is continuous with a pump station every 50 miles and designed to move 20,000 gpm; with AOTs installed. The starting point is where the gathering lines are fed into the Upstream AOT. The oil in the gathering lines is crude and viscous. The Upstream AOT, although capable of receiving the crude oil will be designed to process only the volume of oil that corresponds to the flow volume of the pipeline (20,000 gpm). I image that the Trans- Canada engineers are working on the Upstream AOT and that this AOT is very different than the 4 unit midstream AOT because the inlet is receiving crude oil. It may be a 6 unit AOT. The crude oil input to the system at the gathering lines will create a bottleneck, and that is not a problem, as long as the output from this AOT is 20,000 gpm. Then oil is then on it's way to the next Midstream AOT, and so on, to the storage tank facility.
The AOT concept is a continuous process along the pipeline from start to delivery. An AOT, or even 4 AOTs cannot be installed in the middle of a pipeline, because the reduced oil viscosity would cause the flow velocity of oil to increase, encountering a jamb further down line and creating a suction up line where the oil has not been treated. This is most probably why the 27 engineers at Trans-Canada are developing the Upstream AOT which will be different for every pipeline and require adjustments for all the types of crude oil.
In my previous post I talked about conservation of mass. Basically what I was saying: the volume of oil that enters the pipeline at the upstream is the same as the volume that exits on the downstream end. The AOT allows the oil to travel faster from start to finish. Along the way there are minor fluctuation in the viscosity causing minor changes in the velocity. I am only speculating that these variations are dealt with at the AOTs by using minutes difference in the size of the inlet and outlet pipes.
