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 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.

A microbubble generation module includes a first net, a second net, and a buffering protection device. The first net is provided with a plurality of first through holes and at least one air intake through hole besides to the plurality of first through holes. The second net is arranged on the first net, and provided with a plurality of second through holes. A body accommodates the first net and the second net. The first through hole and the second through hole communicate with each other to form a fluid communicating channel. The air intake through hole is in communication with the fluid communicating channel. The air intake through hole promotes a generation of microbubbles at communicating parts of the plurality of first through holes and the plurality of second through holes when a liquid passes through the fluid communicating channels.

The present inventive concept relates to a system for dissolving gas. Specifically, an embodiment of the present inventive concept provides a system for dissolving gas, the system including a water supply unit configured to supply water, a gas supply unit configured to supply gas, a gas solution generation unit connected to the water supply unit and the gas supply unit, and a bubble gas solution generation unit connected to a rear end of the gas solution generation unit, wherein the gas solution generation unit includes a first gas solution generator connected in parallel to the gas supply unit and configured to generate a first gas solution and at least one second gas solution generator connected in parallel to the gas supply unit, connected in series to the first gas solution generator to receive the first gas solution from the first gas solution generator, and configured to generate a second gas solution having a gas concentration higher than a gas concentration of the first gas solution, and the bubble gas solution generation unit is connected to the second gas solution generator to receive the second gas solution from the second gas solution generator and generates a third gas solution containing a gas whose particles are smaller than particles of the gas contained in the second gas solution.

A microbubble generator is formed from at least two of a flow path constituting section that constitutes a flow path through which a liquid is passable, and a decompression member including a colliding section that is fitted into the flow path constituting section and locally reduces a cross-sectional area of the flow path to generate microbubbles in the liquid that passes through the flow path. This microbubble generator includes an outlet connecting to a negative pressure producing section of the decompression member, an outside air introduction port provided in the flow path constituting section to introduce outside air, and an outside air introduction path communicating between the outside air introduction port and the outlet.

The present invention discloses an apparatus and a method for extracting a component in a solid by using nano-bubbles, the apparatus including a reaction container configured to hold a solid to be extracted, a nano-bubble generating device configured to generate a liquid containing nano-bubbles, and an energy generator, wherein the liquid containing nano-bubbles is used to be mixed with the solid to be extracted, and the energy generator is used to emit energy to the reaction container to burst the nano-bubbles and enhance the extraction effect of the solid in the liquid.

A fine bubble generator which is an ultrafine bubble generator includes a side wall whose inner face is cylindrical, and closing walls closing both ends of the side wall, respectively, with a gas-liquid discharge port in one of the closing walls, wherein a fluid inlet port is provided closer to the gas-liquid discharge port than is a midpoint between both closing walls, and the fluid inlet port penetrates the side wall in a tangential direction of the inner face of the side wall, wherein a spiral groove is formed in the inner face of side wall, and wherein the spiral groove has an angle of inclination of 1° to 10°.

A fine bubble generator which is an ultrafine bubble generator includes a side wall whose inner face is cylindrical, and closing walls closing both ends of the side wall, respectively, with a gas-liquid discharge port in one of the closing walls, wherein a fluid inlet port is provided closer to the gas-liquid discharge port than is a midpoint between both closing walls, and the fluid inlet port penetrates the side wall in a tangential direction of the inner face of the side wall, wherein a spiral groove is formed in the inner face of side wall, and wherein the spiral groove has an angle of inclination of 1° to 10°.

The invention relates to an ultrafine bubble (UFB) generator and a method for generating UFB. The invention also provides an ultrafine bubble-containing liquid and a production method of the liquid. An ultrafine bubble generator is prepared by combining (A) a sophorolipid containing acidic sophorolipid and lactonic sophorolipid in a ratio (mass ratio) of 78:22 to 100:0, (B) a free fatty acid or salt thereof, and (C) a gas generation component.

The invention relates to an ultrafine bubble (UFB) generator and a method for generating UFB. The invention also provides an ultrafine bubble-containing liquid and a production method of the liquid. An ultrafine bubble generator is prepared by combining (A) a sophorolipid containing acidic sophorolipid and lactonic sophorolipid in a ratio (mass ratio) of 78:22 to 100:0, (B) a free fatty acid or salt thereof, and (C) a gas generation component.