Experimental Study on Inlet Structure of the Rod Pump with Down-Hole Oil-Water Hydrocyclone

For the problem of high water cut oil producing well, the technology which the oil-water is separated and injected to down hole can reduce cost price. The down-hole oil-water separation system is composed of double fluid flow pump, oil-water hydrocyclone and oil lift pump. This system runs well on site. Experimental study found that the average separation efficiency of hydrocyclone with rectangular section tangent inlet and flow deflector can reach 99.4%, what's more, the average reduction rate of separation efficiency is only 0.25% in continuous flow and it decreases slowly with the ratio of split ratio divided by oil content increasing. Compared with Archimedes spiral inlet, the former's manufacture technology is simpler and suitable to the rod pump's down-hole oil-water separation system.