An exemplary embodiment includes a blending chamber having a urea inlet, a blending chamber gas inlet, and a blending chamber outlet. A urea source provides a pressurized urea solution to the urea inlet at a urea injection pressure, and a pressurized gas source transmits pressurized gas to the blending chamber gas inlet via a passageway. The passageway is configured to decrease pressure of the pressurized gas transmitted along its length from a first pressure of gas received from the pressurized gas source to a second pressure of gas provided to the blending chamber gas inlet. The first pressure of gas received from the pressurized gas source is greater than the urea injection pressure and the second pressure of gas provided to the blending chamber gas inlet is less than the urea injection pressure.

An apparatus for producing a composition that includes nano-bubbles dispersed in a liquid carrier includes: (a) an elongate housing comprising a first end and a second end, the housing defining a liquid inlet, a liquid outlet, and an interior cavity adapted for receiving the liquid carrier from a liquid source; and (b) a gas-permeable member at least partially disposed within the interior cavity of the housing. The gas-permeable member includes an open end adapted for receiving a pressurized gas from a gas source, a closed end, and a porous sidewall extending between the open and closed ends having a mean pore size no greater than 1.0 m. The gas-permeable member defines an inner surface, an outer surface, and a lumen. The housing and gas-permeable member are configured to form a composition that includes the liquid carrier and the nano-bubbles dispersed therein.

An apparatus for producing a composition that includes nano-bubbles dispersed in a liquid carrier includes: (a) an elongate housing comprising a first end and a second end, the housing defining a liquid inlet, a liquid outlet, and an interior cavity adapted for receiving the liquid carrier from a liquid source; and (b) a gas-permeable member at least partially disposed within the interior cavity of the housing. The gas-permeable member includes an open end adapted for receiving a pressurized gas from a gas source, a closed end, and a porous sidewall extending between the open and closed ends having a mean pore size no greater than 1.0 m. The gas-permeable member defines an inner surface, an outer surface, and a lumen. The housing and gas-permeable member are configured to form a composition that includes the liquid carrier and the nano-bubbles dispersed therein.

A swirler includes a swirler body and a plurality of axial swirl vanes extending radially outward from the swirler body. At least one of the swirler body or vanes includes a spring channel defined therethrough. A fuel injector for a gas turbine engine can include an inner air swirler and/or outer air swirler as described above.

A gas delivery system and method for delivering reactants such as a first gas through a first conduit and a second gas through at least one second conduit, for example, through a plurality of second conduits. The plurality of second conduits may each have a length, wherein at least a portion of the length is entirely disposed within the first conduit. In an implementation, the first conduit may deliver carbon monoxide and the one or more second conduits may deliver carbon monoxide doped with a catalyst such as iron pentacarbonyl. The first and second gases may be introduced into a reaction vessel such as a reactor chamber and used to form carbon nanotubes.

An apparatus for producing a composition that includes nano-bubbles dispersed in a liquid carrier includes: (a) an elongate housing comprising a first end and a second end, the housing defining a liquid inlet, a liquid outlet, and an interior cavity adapted for receiving the liquid carrier from a liquid source; and (b) a gas-permeable member at least partially disposed within the interior cavity of the housing. The gas-permeable member includes an open end adapted for receiving a pressurized gas from a gas source, a closed end, and a porous sidewall extending between the open and closed ends having a mean pore size no greater than 1.0 m. The gas-permeable member defines an inner surface, an outer surface, and a lumen. The housing and gas-permeable member are configured to form a composition that includes the liquid carrier and the nano-bubbles dispersed therein.

The present invention relates to an initiator injection nozzle (1) for mixing an initiator with a process fluid. The initiator injection nozzle comprises a body (10) comprising (i) a process fluid inlet port (11) to receive the process fluid and an outlet port (17); (ii) a process fluid flow passage (13) through which the process fluid traverses along a process fluid central flow axis (15) between the process fluid inlet port (11) and the outlet port (17), the process fluid flow passage 13 having a constricting portion (12), a throat (14) and an expanding portion (16); (iii) an initiator inlet (30) to receive the initiator and an initiator outlet (32); and (iv) an initiator fluid flow passage (34) through which the initiator traverses along an initiator central flow axis (35) between the initiator (inlet 30) and the initiator outlet (32), the process fluid flow passage (13) intersecting the initiator fluid flow passage (34) at the throat (14). At least one elongated vane (20) having a leading end (22) and a trailing end (26) is provided within the process fluid flow passage (13) and extends along the process fluid central flow axis (15), wherein the initiator outlet (32) is disposed on a surface (24) of the vane (20). The initiator injection nozzle is characterised in that the initiator outlet (32) is disposed on a portion of an axial edge (24) of the vane (20).

A fine bubble generator may include an inlet; an outlet; a first fine bubble generation portion; and a second fine bubble generation portion. The first fine bubble generation portion includes: a diameter-reducing flow path and a diameter-increasing flow path. The second fine bubble generation portion includes: a first swirling flow generation portion; and a second swirling flow generation portion. The first swirling flow generation portion includes: a first outer peripheral portion; and a plurality of first vanes disposed configured to generate a first swirling flow flowing in a first swirling direction with respect to a center axis of the second fine bubble generation portion. The second swirling flow generation portion includes: a second outer peripheral portion; and a plurality of second vanes configured to generate a second swirling flow flowing in a second swirling direction opposite to the first swirling direction with respect to the center axis.

A nozzle for injecting a first liquid mass into a stream of second liquid mass flowing within a pipe, comprising a first, outer, cylinder and second, inner, cylinder concentrically arranged about a nozzle axis, securing means for securing the nozzle to a wall of the pipe with the nozzle axis orthogonal to the pipe wall, the nozzle projecting into an interior of the pipe in use, duct means for receiving the first liquid mass and transporting it to the interior of the inner and outer cylinders, the inner cylinder comprising at least one hole arranged to expel liquid therethrough, and the outer cylinder comprising at least one hole arranged to expel liquid therethrough.

A method and apparatus for producing hydrogen gas whereby a nanobubble generator introduces nanobubbles at a concentration of at least 10.sup.7 nanobubbles per cm.sup.3 into an electrolytic cell comprising a pair of electrodes and a hydrogen-containing, electrolyzable liquid, and the electrolytic cell is operated to produce hydrogen gas.