A device for separating low density materials such as gas bubbles from a liquid is disclosed which comprises a chamber defined by an inner wall which in turn defines generally circular, transverse cross-sections about a longitudinal axis. The liquid inlet port extends through the inner wall in a position to pass liquid into the chambers circumferentially about the inner wall for swirling flow within the chamber. Accordingly, lower density components of the fluid, such as bubbles, migrate away from the inner wall toward the center of the swirling flow. An outlet port extends through the inner wall, and is spaced from the inlet port, to collect fluid which is free from the low density materials.

Swirling flow bubble trap

A novel liquid filter of the "outside-in" type is disclosed, comprising a hollow tubular housing, a concentrically disposed perforated tubular core surrounded by a cylindrical filter element and communicating with a liquid outlet in the bottom wall of the housing, and a filter element cap covering the upper ends of the perforated core and filter element. A gas vent is located at the highest point in the top wall of the housing, which is at the center of the top wall. The liquid inlet and filter element cap are designed to provide for establishment of a stable swirling flow outside the filter element and above the filter element cap. An improved means of bonding upper and lower cup-like portions together to form a hollow tubular housing with high resistance to rupture under pressure is also disclosed. The filter of the invention is particularly suited for use in extracorporeal blood flow circuits, most particularly as an arterial blood filter located downstream from a blood oxygenator.

Arterial blood filter with improved gas venting

A multi-stage, recycling, centrifugal, flotation separator system, comprising a circular cylindrical vessel with vertical axis, having a horizontal tray positioned inside the vessel near the top, the tray having an axial opening. Means for introducing air under pressure into the vessel at the top thereof, and means for introducing contaminated liquid into the vessel through a tangential pipe, under pressure, at a level below the tray. Means to recycle air from the top of the vessel into the inlet line and to mix the recycled air with the contaminated liquid before entry into the vessel. Means to recycle liquid from the bottom of said vessel, through a tangential pipe into the vessel at a level below that of the contaminated liquid, and means to mix recycled air with the recycled liquid prior to entry into the vessel.

Centrifugal flotation separator

An oil filter comprising a housing opened at one end, a first separator unit in the housing for removing solid contaminants from the oil and a second separator unit for removing gaseous contaminants. The first separator unit includes a cylindrical filter element and upper and lower end plates attached to the upper and lower ends of the filter element. The second separator unit is disposed in the space defined by the inner periphery of the filter element and between the upper and lower end plates. It includes a chamber arranged to generate a vortical flow of the oil introduced thereof to thereby separate gas-rich oil which gathers in an axially central portion of the chamber, a first outlet for discharging the gas-rich oil and a second outlet for the oil containing little gaseous contaminants, the first and second outlets extending into the housing from the open end thereof.

Oil filter I

A gas treatment system for liquids can increase gas exposure and contact time. A liquid stream into which treatment gas is added is directed into a vortex chamber (130). The vortex chamber (130) creates a downward spiral flow of the liquid stream forcing it into an upper end inlet (145) of a contact tank (114). The liquid stream with entrained gas bubbles is forced to move downwardly through the tank to a lower end outlet (122). The flow then moves upwardly to a degassing chamber (146) wherein the treatment gas is separated from the liquid and delivered through an outlet (124) for use. Because the entrained bubbles are forced downwardly through the contact tank (114), the gas bubbles remain quite small and contact time is prolonged. Release of the treatment gas is further facilitated by positioning the degassing chamber (146) at an elevated position which promotes gas bubble expansion, combination and release.

System for treating liquids with a gas

In a vortex type de-aerator for separating air and other gases from a flowing liquid, having a central perforate tube located within a vessel having a tangential inlet and a tangential outlet, a vortex stabilising baffle device is located adjacent to the inlet for stabilising the vortex flow and for shielding separated gas from any disturbances at the inlet.

W Stethem

Papers

Vortex de-aerator