39results about How to "Reduce recirculation" patented technology

A foldable, intravascularly insertable blood pump (10) comprises a foldable, radially delivering impeller (20) accommodated in a foldable housing or envelope (24). Axially before and behind the impeller a clearance (60) is provided between the impeller (20) and the front and back walls (32, 62) of the housing (24), the clearance being at least 0.2 mm. Preferably, the space defined between adjacent blades (54) of the impeller (20) is open towards the front wall (32) of the housing (24).

A hemodialysis and vascular access system comprises a subcutaneous composite PTFE silastic arteriovenous fistula having an indwelling silastic venous end which is inserted percutaneously into a vein and a PTFE arterial end which is anastomosed to an artery. Access to a blood stream within the system is gained by direct puncture of needle(s) into a needle receiving site having a tubular passage within a metal or plastic frame and a silicone upper surface through which needle(s) are inserted. In an alternate embodiment of the invention, percutaneous access to a blood stream may be gained by placing needles directly into the system (i.e. into the PTFE arterial end). The invention also proposes an additional embodiment having an arterialized indwelling venous catheter where blood flows from an artery through a tube and a port into an arterial reservoir and is returned to a vein via a port and a venous outlet tube distinct and distant from the area where the blood from the artery enters the arterial reservoir. The site where blood is returned to the vein is not directly fixed to the venous wall but is free floating within the vein. This system provides a hemodialysis and venous access graft which has superior longevity and performance, is easier to implant and is much more user friendly.

Disclosed is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit. The apparatus has an inlet and an outlet that is located radially outward from the inlet in order to define a flowpath through the apparatus. The apparatus comprises: a core that is substantially centrally located in the apparatus and to which blood from a patient can be supplied through the inlet; a heat exchanger comprising a plurality of heat transfer elements that are arranged around the core and between which blood from the core can move radially outward; and an oxygenator comprising a plurality of gas exchange elements that are arranged around the heat exchanger and between which blood from the heat exchanger can move radially outward before exiting the apparatus through the outlet.

Described is a method of making an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit, the steps comprising: providing a core through which blood can be supplied to the apparatus from a patient; providing a heat exchanger about the core such that blood from the core can move radially outward through the heat exchanger; providing an oxygenator about the heat exchanger such that blood from the heat exchanger can move radially outward through the oxygenator; and placing the core, heat exchanger and oxygenator in a housing that includes an inlet in communication with the core and an outlet that is located radially outward from the inlet in order to define a flowpath for blood through the apparatus.

A centrifugal pump includes plural pump stages, each comprising an impeller assembly, a stationary disc assembly and a diffuser assembly, all disposed about an impeller shaft. A floating impeller hub seal is supported by a diffuser assembly to minimize fluid recirculation. A thrust washer is disposed around the impeller shaft and is engageable with an impeller hub and the hub seal. A wear ring is secured to a disc assembly and engageable with a wear surface on the impeller.

A hemodialysis and vascular access system comprises a subcutaneous composite PTFE silastic arteriovenous fistula having an indwelling silastic venous end which is inserted percutaneously into a vein and a PTFE arterial end which is anastomosed to an artery. Access to a blood stream within the system is gained by direct puncture of needle(s) into a needle receiving site having a tubular passage within a metal or plastic frame and a silicone upper surface through which needle(s) are inserted. In an alternate embodiment of the invention, percutaneous access to a blood stream may be gained by placing needles directly into the system (i.e. into the PTFE arterial end). The invention also proposes an additional embodiment having an arterialized indwelling venous catheter where blood flows from an artery through a tube and a port into an arterial reservoir and is returned to a vein via a port and a venous outlet tube distinct and distant from the area where the blood from the artery enters the arterial reservoir. The site where blood is returned to the vein is not directly fixed to the venous wall but is free floating within the vein. This system provides a hemodialysis and venous access graft which has superior longevity and performance, is easier to implant and is much more user friendly.

A fuel injector for a gas turbine engine has an inlet fitting, a fuel nozzle, and a housing stem with a pair of fuel conduits fluidly interconnecting the nozzle and fitting. The fuel nozzle includes an annular secondary fuel passageway directing fuel from one fuel conduit to an annular discharge orifice at a discharge end of the nozzle. The secondary fuel passageway is defined between an outer, annular fuel conduit portion and a primary adapter. The primary adapter has an outer surface with a distinct, radially-outwardly-projecting annular shoulder to restrict flow through the secondary passageway and provide substantially uniform distribution of flow through the passageway downstream of the shoulder, for improved combustion and flame stability.

Described is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit, the apparatus having an inlet and an outlet that is located radially outward from the inlet in order to define a flowpath through the apparatus, the apparatus comprising: a core in communication with the inlet such that blood from a patient can be supplied to the core, the core comprising a first element and a second element that interfit to define openings, wherein the elements and the openings together enhance flow of blood from the patient radially outward from the core; a heat exchanger that is arranged about the core and through which blood from the core can move radially outward; and an oxygenator that is arranged about the heat exchanger and through which blood from the heat exchanger can move radially outward before exiting the apparatus through the outlet.

A mass transfer column includes a feed device that is used to de-entrain liquid and more uniformly distribute vapor across a horizontal cross section of the column after a vapor or mixed phase stream has been directed into the column through a radially oriented feed nozzle. The feed device includes an annular passageway formed in the spacing between the column shell and an inner wall spaced inwardly from the shell. A deflector with oppositely directed deflecting surfaces is positioned at an inlet from the feed nozzle to the annular passageway and splits the vapor or mixed phase stream into two roughly equal streams that flow in opposite circumferential directions in the annular passageway. At least one pair of turning vanes is spaced on opposite sides of the deflecting surfaces in the annular passageway to create subpassages through which the vapor or mixed phase stream flows. The subpassages reduce the amount of vapor or mixed phase stream flow that impacts against the inner wall of the feed device at the inlet. The turning vanes unexpectedly reduce the pressure drop that occurs as the vapor or mixed phase stream is redirected from its radial entry direction to the circumferential direction in the annular passageway. By reducing the pressure drop, improvements in product yield and vapor distribution can be achieved.

Described is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit comprising: an inlet mandrel that is configured such that the blood moves radially outward from the inlet mandrel through the openings in a radial direction; a heat exchanger arranged around the inlet mandrel, wherein blood can move radially outward with the transfer of heat to or from the blood; an oxygenator arranged around the heat exchanger, wherein blood can move from the heat exchanger radially outward with the transfer of oxygen into the blood; and a housing that houses the inlet mandrel, the heat exchanger and the oxygenator, and that comprises a blood inlet in communication with the inlet mandrel in order to allow blood to enter the apparatus from the patient, and a blood outlet in communication with the oxygenator in order for blood to exit the apparatus, wherein the blood outlet is located in the housing radially outward from the inlet.

In a rotating disk reactor for growing epitaxial layers on substrate or other CVD reactor system, gas directed toward the substrates at gas inlets at different radial distances from the axis of rotation of the disk has both substantially the same gas flow rate / velocity and substantially the same gas density at each inlet. The gas directed toward portions of the disk remote from the axis may include a higher concentration of a reactant gas than the gas directed toward portions of the disk close to the axis, so that portions of the substrate surfaces at different distances from the axis receive substantially the same amount of reactant gas per unit area, and a combination of carrier gases with different relative molecular weights at different radial distances from the axis of rotation are employed to substantially make equal the gas density in each region of the reactor. The system may be applied with a combination or carrier gases at multiple gas inlets, a combination of carrier and reactant gases at multiple inlets, and may be used with an arbitrarily large number of gases, when at least two gases of different molecular weights are provided. A linear flow pattern is achieved within the reactor, avoiding laminar recirculation areas, and permitting uniform deposition and growth of epitaxial layers on the substrate.

A blood purification apparatus includes a blood circuit having arterial and venous blood circuits, a blood pump, a blood purifying device, an indicator applying device that applies a predetermined indicator to the blood flowing extracorporeally through the blood circuit, a detecting device that detects the indicator applied by the indicator applying device, an arithmetic device that calculates, based on the indicator detected by the detecting device, a recirculation rate, and a calculating device that calculates an ideal extracorporeally circulating blood flow that results in the recirculation rate being no more than a predetermined value when the recirculation rate calculated by the arithmetic device is greater than the predetermined value. The recirculation rate is a proportion of a recirculated blood flow, which is reintroduced to the patient from the venous blood circuit and directed again to the arterial blood circuit, relative to an extracorporeally circulating blood flow.

A centrifugal blower includes a main scroll portion and a scroll opening through which air is discharged. A transitional portion conducts air discharged through the scroll opening away from the blower. The transitional portion includes an internal passageway that provides for the smooth passage of air essentially without causing any abrupt changes in the direction of the flow of the air through the passageway. An impeller assembly can be mounted within the main scroll portion for rotation so as to circulate the air in a spiral path within the main scroll portion and force the air through the scroll opening and the passageway in the transitional portion. The impeller assembly can have a platen that has a perimeter and a plurality of impeller blades mounted at the platen for rotation with the platen. Each impeller blade can have a distal end that extends beyond the perimeter of the platen.

Disclosed is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit. The apparatus has an inlet and an outlet that is located radially outward from the inlet in order to define a flowpath through the apparatus. The apparatus comprises: a core that is substantially centrally located in the apparatus and to which blood from a patient can be supplied through the inlet; a heat exchanger comprising a plurality of heat transfer elements that are arranged around the core and between which blood from the core can move radially outward; and an oxygenator comprising a plurality of gas exchange elements that are arranged around the heat exchanger and between which blood from the heat exchanger can move radially outward before exiting the apparatus through the outlet.

A method for retrofitting a pulverized coal boiler in an air combustion boiler system is disclosed, which has a plurality of burners over a plurality of stages along the vertical direction on a wall surface of a furnace of the pulverized coal boiler and an after-air port for introducing air for two-stage combustion located above the burners to retrofit into a two-stage combustion pulverized coal boiler in an oxyfuel combustion boiler system.

An implantable pump system is provided, suitable for use as a left ventricular assist device (LVAD) system, having an implantable pump, a battery, a controller, and a programmer. The implantable pump includes a flexible membrane coupled to an actuator assembly via a skirt that extends toward the inlet of the pump and curves to guide blood toward the outlet. The actuator assembly is magnetically engagable with electromagnetic coils, so that when the electromagnetic coils are energized, the actuator assembly causes wavelike undulations to propagate along the flexible membrane to propel blood from the inlet, across the skirt, and through the outlet of the implantable pump. The controller may be programmed by a programmer to operate at frequencies and duty cycles that mimic physiologic flow rates and pulsatility while operating in an efficient manner that avoids thrombus formation, hemolysis and / or platelet activation.

A mass transfer column includes a feed device that is used to de-entrain liquid and more uniformly distribute vapor across a horizontal cross section of the column after a vapor or mixed phase stream has been directed into the column through a radially oriented feed nozzle. The feed device includes an annular passageway formed in the spacing between the column shell and an inner wall spaced inwardly from the shell. A deflector with oppositely directed deflecting surfaces is positioned at an inlet from the feed nozzle to the annular passageway and splits the vapor or mixed phase stream into two roughly equal streams that flow in opposite circumferential directions in the annular passageway. At least one pair of turning vanes is spaced on opposite sides of the deflecting surfaces in the annular passageway to create subpassages through which the vapor or mixed phase stream flows. The subpassages reduce the amount of vapor or mixed phase stream flow that impacts against the inner wall of the feed device at the inlet. The turning vanes unexpectedly reduce the pressure drop that occurs as the vapor or mixed phase stream is redirected from its radial entry direction to the circumferential direction in the annular passageway. By reducing the pressure drop, improvements in product yield and vapor distribution can be achieved.

Disclosed is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit. The apparatus has an inlet and an outlet that is located radially outward from the inlet in order to define a flowpath through the apparatus. The apparatus comprises at least one integrated pump that is provided in a core of the apparatus and to which blood from a patient can be supplied through the inlet; a heat exchanger comprising a plurality of heat transfer elements that are arranged around the at least one integrated pump and between which blood from the at least one integrated pump can move radially outward; an oxygenator comprising a plurality of gas exchange elements that are arranged around the heat exchanger and through which blood from the heat exchanger can move radially outward; and an optional filter arranged around the oxygenator and through which blood from the oxygenator can move radially outward before exiting the apparatus through the outlet.

Disclosed is a method for production of a lower olefin from a raw material containing dimethyl ether (DME), which can produce a lower olefin (e.g., propylene) with good yield and in an economically advantageous manner by prolonging the time until the temporary deactivation of a zeolite catalyst and preventing the permanent deactivation of the catalyst, can reduce the amount of water to be recycled to increase the thermal efficiency of the process, and can simplify the facilities and operations. Also disclosed is a method for improving the yield of propylene with good efficiency under practical operation conditions. A feed gas which comprises a DME-containing raw material gas and an additive gas and further contains steam at a specific proportion is introduced into an olefin production reactor to contact the feed gas with a zeolite catalyst, thereby producing a hydrocarbon product containing a C2-C5 olefin. Propylene or the like is separated / collected from the hydrocarbon product, and at least a part of the remainder is used as at least a part of the additive gas.

Tube heat exchanger comprising finned tubes, wherein the tubes extend in a certain axial direction and are provided with heat exchange fins. Each fin has a heat exchange surface surrounding a tube that extends in a certain radial direction in relation to the tube and which is relief structured to form grooves spaced apart from one another in said radial direction. The grooves of a fin have different dimensions that decrease on moving away from the tube in said radial direction so as to form a guide for a fluid around the tube.

Disclosed is an apparatus for oxygenating and controlling the temperature of blood in an extracorporeal circuit. The apparatus has an inlet and an outlet that is located radially outward from the inlet in order to define a flowpath through the apparatus. The apparatus comprises: at least one pump that is provided in a core of the apparatus and to which blood from a patient can be supplied through the inlet; a heat exchanger comprising a plurality of heat transfer elements that are arranged around the at least one pump and between which blood from the at least one pump can move radially outward; and an oxygenator comprising a plurality of gas exchange elements that are arranged around the heat exchanger and through which blood from the heat exchanger can move radially outward before exiting the apparatus through the outlet.

A method for retrofitting a pulverized coal boiler in an air combustion boiler system is disclosed, which has a plurality of burners over a plurality of stages along the vertical direction on a wall surface of a furnace of the pulverized coal boiler and an after-air port for introducing air for two-stage combustion located above the burners to retrofit into a two-stage combustion pulverized coal boiler in an oxyfuel combustion boiler system.

A hydraulic turbine is adapted to introduce oxygen into a water flowing through a water passageway of a turbine. The turbine has a circumferential chamber formed between a rotating band and a stationary discharge ring. The chamber has a gas admission aperture for receiving an oxygen containing gas into the chamber. A downstream end portion of the band has a plurality of spaced apart vanes providing chamber outlet passageways between the vanes and through the band. The vanes are configured to rotate with the band and to draw the oxygen containing gas and water from the chamber through the outlet passageways in the band and into the water passageway.

A hydraulic turbine is adapted to introduce oxygen into a water flowing through a water passageway of a turbine. The turbine has a circumferential chamber formed between a rotating band and a stationary discharge ring. The chamber has a gas admission aperture for receiving an oxygen containing gas into the chamber. A downstream end portion of the band has a plurality of spaced apart vanes providing chamber outlet passageways between the vanes and through the band. The vanes are configured to rotate with the band and to draw the oxygen containing gas and water from the chamber through the outlet passageways in the band and into the water passageway.

A flight vehicle has a propulsion system that includes an air inlet, an isolator (or diffuser) downstream of the air inlet, and a combustor downstream of the isolator. The isolator includes an obstruction that protrudes inwardly from an inner wall of the isolator, into the flow channel in which air flows through the isolator. The obstruction diverts the flow to either side of it. Downstream of the obstruction the flow on either side of the obstruction comes together again, leading to mixing of the flow, for example including mixing of low energy and boundary layer flow with high energy flow. This mixing of flow may make for a more uniform flow at the exit of the isolator. In addition the obstruction may help fix the location of shocks within the isolator, providing longer flow mixing length in the isolator.

The present invention relates to a process for removing hydrocarbons comprising the steps of: (A) passing a stream of a solution into a separator wherein a liquid phase comprising polymer and a vapourphase coexist; (B) withdrawing a vapour stream and a concentrated solution stream from the separator; (C) passing at least a part of the vapour stream into a first fractionator; (D) withdrawing a first overhead stream and a first bottom stream from the first fractionator; (E) passing the first overhead stream to a second fractionator; (F) withdrawing a second overhead stream and a second bottom stream from the second fractionator; (G) passing the second overhead stream to a third fractionator; (H) withdrawing a third overhead stream and a third bottom stream from the third fractionator; characterised in that at least a part of the third bottom stream is withdrawn as a purge stream.

The invention provides a device and a method for maintaining high-performance plasma. The device comprises a central column; a vacuum container, which is arranged around the central column, and the vacuum container is used for containing the formed plasma; a plasma magnetic confinement system, which is used for limiting, forming and controlling the plasma in the vacuum container through a magnetic field, so that the plasma body forms a configuration with a plurality of fluids, wherein the multiple fluids form multiple layers from inside to outside, the fluid located on the outer layer surrounds the fluid located on the inner layer, and the adjacent fluids are at least partially overlapped. In the application, the configuration with a plurality of fluids is formed, wherein the high-energy electron fluid surrounds the thermionic fluid and the thermionic fluid, and the maintenance of the high-energy electron fluid enables the circumferential current to have a very large circumferential current outside the outermost closed magnetic surface, so that plasma turbulence and energy diffusion are effectively avoided; therefore, the recycling phenomenon of particles on the outermost closed magnetic surface is reduced, and the energy constraint capacity and stability of thermionic ions and thermionic electrons in the closed magnetic surface are effectively improved.