Provided is a liquid supply apparatus which is capable of directly taking in a liquid from a flow channel and appropriately mixing a gas into the liquid when generating-nanobubbles in the liquid using an ultrafine bubble generating apparatus. The liquid supply apparatus comprises a flow channel for a liquid supplied from a liquid supply source and an ultrafine bubble generating apparatus for generating nanobubbles in the liquid. The ultrafine bubble generating apparatus is provided with: a liquid ejector for ejecting the liquid taken in from the flow channel; a gas mixer for pressurizing and mixing a gas into the liquid ejected from the liquid ejector; and a nanobubble-generating nozzle for generating nanobubbles in the liquid by passing the liquid with intermixed gas therethrough. The pressure of the liquid in the flow channel flowing into the liquid ejector from the upstream-side of the liquid ejector is a positive pressure and, between the liquid ejector and the-nanobubble-generating nozzle, the gas mixer pressurizes and mixes the gas into the liquid, which is flowing in a pressurized state toward the nanobubble-generating nozzle.

Provided is a liquid supply apparatus which is capable of directly taking in a liquid from a flow channel and appropriately mixing a gas into the liquid when generating-nanobubbles in the liquid using an ultrafine bubble generating apparatus. The liquid supply apparatus comprises a flow channel for a liquid supplied from a liquid supply source and an ultrafine bubble generating apparatus for generating nanobubbles in the liquid. The ultrafine bubble generating apparatus is provided with: a liquid ejector for ejecting the liquid taken in from the flow channel; a gas mixer for pressurizing and mixing a gas into the liquid ejected from the liquid ejector; and a nanobubble-generating nozzle for generating nanobubbles in the liquid by passing the liquid with intermixed gas therethrough. The pressure of the liquid in the flow channel flowing into the liquid ejector from the upstream-side of the liquid ejector is a positive pressure and, between the liquid ejector and the-nanobubble-generating nozzle, the gas mixer pressurizes and mixes the gas into the liquid, which is flowing in a pressurized state toward the nanobubble-generating nozzle.

An ultrafine bubble water manufacturing device includes a whirlpool pump, an ejector, a cascade pump, a branch portion on the downstream side of the cascade pump, a return path which communicates from the branch portion between the ejector and the cascade pump, a flow rate adjusting valve and a first ultrafine bubble manufacturing unit interposed in the return path, an emission path which communicates with the branch portion, a second ultrafine bubble manufacturing unit interposed in the emission path and a control device. The control device controls an air amount adjusting valve, the whirlpool pump, the cascade pump and the flow rate adjusting valve based on the measurement values of a concentration meter for the emission path and first and second pressure gauges and on the downstream and upstream sides of the cascade pump.

An ultrafine bubble water manufacturing device includes a whirlpool pump, an ejector, a cascade pump, a branch portion on the downstream side of the cascade pump, a return path which communicates from the branch portion between the ejector and the cascade pump, a flow rate adjusting valve and a first ultrafine bubble manufacturing unit interposed in the return path, an emission path which communicates with the branch portion, a second ultrafine bubble manufacturing unit interposed in the emission path and a control device. The control device controls an air amount adjusting valve, the whirlpool pump, the cascade pump and the flow rate adjusting valve based on the measurement values of a concentration meter for the emission path and first and second pressure gauges and on the downstream and upstream sides of the cascade pump.

A micro bubble generation method and generation device. The micro bubble generation method includes: passing a gas through a microporous material, the gas forming micro bubbles at an interface between the microporous material and liquid, the bubbles being adsorbed on the surface of the microporous material; impacting the micro bubbles adsorbed on the microporous material by relative motion of the microporous material and the liquid, such that the micro bubbles detach from the microporous material and enter into the liquid. The micro bubble generation device includes a gas accommodating chamber (1) disposed below the liquid surface, and a gas transmission pipeline (3). A microporous material layer (2) is arranged around the periphery of the gas accommodating chamber (1). The gas in the gas accommodating chamber (1) passes through the microporous material layer (2) by gas pressure to form micro bubbles on the outer surface thereof. The microporous material layer (2) moves and/or the liquid outside the microporous material layer (2) moves to cut the micro bubbles.

An ultrafine bubble-containing liquid producing apparatus and method enables preventing ultrafine bubbles over a long period of operation by, based on a predetermined condition, switching between a first mode where a liquid between an ultrafine bubble generating unit and a storing chamber is circulated at a first flow velocity and a second mode where the liquid is circulated at a second flow velocity higher than the first flow velocity.

An ultrafine bubble-containing liquid producing apparatus and method enables preventing ultrafine bubbles over a long period of operation by, based on a predetermined condition, switching between a first mode where a liquid between an ultrafine bubble generating unit and a storing chamber is circulated at a first flow velocity and a second mode where the liquid is circulated at a second flow velocity higher than the first flow velocity.

The present disclosure relates to a system and method for treating wastewater, the method comprising the steps of: providing a vessel for receiving wastewater and a gas, wherein the gas comprises one or more constituent gas components; directing the wastewater and a first gas component of the gas to the vessel; reducing the temperature of the contents of the vessel from a first temperature to a second temperature to facilitate the formation of clathrate hydrates comprising the wastewater and the first gas component; increasing the temperature of the contents of the vessel with respect to the second temperature to facilitate melting of the clathrate hydrates; and removing clean water and/or the first gas component from the vessel.

Initial liquid containing fine bubbles is produced by mixing water and air (step S11). Fine bubbles have diameters of less than 1 m. The density of bubbles in the initial liquid is measured (step S13), and when the measured density is less than a target density (step S14), the initial liquid is heated and reduced in pressure so that the liquid is vaporized (step S15). As a volume of the liquid decreases, the density of fine bubbles increases, and high-density fine bubble-containing liquid is easily obtained. Alternatively, by increasing the density of fine bubbles in the initial liquid with using a filter that does not pass all fine bubbles, high-density fine bubble-containing liquid is easily acquired (step S15). When the density of bubbles in the initial liquid is greater than the target density, the initial liquid is diluted (step S16).

To provide a nanobubble generating nozzle that is compact and capable of generating nanobubbles with high efficiency. The problem is solved by a nanobubble generating nozzle and a nanobubble generator comprising this nanobubble generating nozzle. The nanobubble generating nozzle comprises an introduction part for introducing a mixed fluid of a liquid and a gas into an interior thereof, a jetting part for feeding out the mixed fluid containing nanobubbles of the gas, and a nanobubble generating structure part for generating nanobubbles of the gas, between the introduction part and the jetting part. The nanobubble generating structure part comprises a plurality of flow paths having different cross-sectional areas through which the mixed fluid of the liquid and the gas is passed, in an axial direction of the nanobubble generating nozzle.