A centrifugal gas compressor fed with a gas and a processing liquid comprises a rotor rotated by a prime mover. The rotor defines an internal axial cavity with a cylindrical surface, an annular peripheral collection cavity, and a tapered radial channel fluidly connecting the internal axial cavity and the annular peripheral collection cavity. With each rotation of the rotor, a portion of the processing fluid is swept into the inlet of the tapered radial channel and travels radially as a fluid piston under centrifugal force pushing and compressing a column of gas entrained in front of said fluid piston, and is expelled into the annular peripheral collection cavity where it undergoes centrifugal separation, leaving the compressed gas to be drawn off through the compressed gas outlet for downstream use. A method for compressing a gas is also provided.

A method for removing hydrogen sulphide ions (HS.sup.−) from a liquor (300) of a pulp mill process, the method comprising pumping the liquor (300) to an injector arrangement (710) using a pump arrangement (720) such that the pumping of the liquor (300) through a jet nozzle (115) generates suction at a gas inlet (130), whereby reagent gas (310) is mixed with the liquor (300), and letting out the treated liquor (300) from the injector arrangement (710) to a vessel (200). In this way, the liquor (300) is treated to form at least partly treated liquor (300). A corresponding use of an injector arrangement. A system for performing the method.

A method for removing hydrogen sulphide ions (HS.sup.−) from a liquor (300) of a pulp mill process, the method comprising pumping the liquor (300) to an injector arrangement (710) using a pump arrangement (720) such that the pumping of the liquor (300) through a jet nozzle (115) generates suction at a gas inlet (130), whereby reagent gas (310) is mixed with the liquor (300), and letting out the treated liquor (300) from the injector arrangement (710) to a vessel (200). In this way, the liquor (300) is treated to form at least partly treated liquor (300). A corresponding use of an injector arrangement. A system for performing the method.

An aspirator air vent valve may include an air vent valve body coupled with an aspirator body and a pipe fitting. The air vent valve body may include an air vent valve air channel defined by an inner wall of the air vent valve body and disposed between the aspirator body and the pipe fitting. The aspirator air vent valve may further include a vent passage defined by a first vent wall and a second vent wall and disposed between an outer wall and the inner wall of the air vent valve body, wherein the vent passage is in fluid communication with the air vent valve air channel. The aspirator air vent valve may further include a plunger coupled with the air vent valve body.

A centrifugal gas compressor fed with a gas and a processing liquid comprises a rotor rotated by a prime mover. The rotor defines an internal axial cavity with a cylindrical surface, an annular peripheral collection cavity, and a tapered radial channel fluidly connecting the internal axial cavity and the annular peripheral collection cavity. With each rotation of the rotor, a portion of the processing fluid is swept into the inlet of the tapered radial channel and travels radially as a fluid piston under centrifugal force pushing and compressing a column of gas entrained in front of said fluid piston, and is expelled into the annular peripheral collection cavity where it undergoes centrifugal separation, leaving the compressed gas to be drawn off through the compressed gas outlet for downstream use. A method for compressing a gas is also provided.

A gas compressor comprising a drum affixed to a rotating shaft, the drum including a plurality of compression channels between a common pressure zone and an interior surface of the drum distal to an axis of rotation. A static vane return assembly adjacent the compression channels includes vanes extending from an inlet at an outer circumference to the common pressure zone and directing gas into the common pressure zone, either through the vanes or via separate channels or ducts. Fluid inside the rotating dmm forms an annular lake that is drawn through the vanes and into the common pressure zone. Fluid is then forced into the compression channels where gas in the fluid is compressed as it travels from the common pressure zone toward the interior surface. The pressurized gas is separated from the liquid prior to leaving the compression channel assembly while the liquid is returned to the lake.

A gas compressor comprising a drum affixed to a rotating shaft, the drum including a plurality of compression channels between a common pressure zone and an interior surface of the drum distal to an axis of rotation. A static vane return assembly adjacent the compression channels includes vanes extending from an inlet at an outer circumference to the common pressure zone and directing gas into the common pressure zone, either through the vanes or via separate channels or ducts. Fluid inside the rotating dmm forms an annular lake that is drawn through the vanes and into the common pressure zone. Fluid is then forced into the compression channels where gas in the fluid is compressed as it travels from the common pressure zone toward the interior surface. The pressurized gas is separated from the liquid prior to leaving the compression channel assembly while the liquid is returned to the lake.

A gas compressor comprising a drum affixed to a rotating shaft, the drum including a plurality of compression channels between a common pressure zone and an interior surface of the drum distal to an axis of rotation. A static vane return assembly adjacent the compression channels includes vanes extending from an inlet at an outer circumference to the common pressure zone and directing gas into the common pressure zone, either through the vanes or via separate channels or ducts. Fluid inside the rotating drum forms an annular lake that is drawn through the vanes and into the common pressure zone. Fluid is then forced into the compression channels where gas in the fluid is compressed as it travels from the common pressure zone toward the interior surface. The pressurized gas is separated from the liquid prior to leaving the compression channel assembly while the liquid is returned to the lake.

A gas compressor comprising a drum affixed to a rotating shaft, the drum including a plurality of compression channels between a common pressure zone and an interior surface of the drum distal to an axis of rotation. A static vane return assembly adjacent the compression channels includes vanes extending from an inlet at an outer circumference to the common pressure zone and directing gas into the common pressure zone, either through the vanes or via separate channels or ducts. Fluid inside the rotating drum forms an annular lake that is drawn through the vanes and into the common pressure zone. Fluid is then forced into the compression channels where gas in the fluid is compressed as it travels from the common pressure zone toward the interior surface. The pressurized gas is separated from the liquid prior to leaving the compression channel assembly while the liquid is returned to the lake.

A propeller-less unmanned aerial vehicle having a body having a plurality of channels, an inlet formed in the body and configured to allow air flow to enter the plurality of channels from an exterior of the body, an anechoic chamber formed in the body and coupled to the plurality of channels, a rotor comprising a plurality of angled fins located in the anechoic chamber, a control system configured to direct air flow within the plurality of channels, and one or more circular tubes coupled to the exterior of the body and in communication with the plurality of channels. The air flows into the body through the inlet, into the plurality of channels and the anechoic chamber, and exits through the one or more circular tubes to provide lift and directional control to the propeller-less unmanned aerial vehicle.