A fine bubble generator may include an inlet into which gas-dissolved water in which gas is dissolved flows, an outlet out of which the gas-dissolved water flows; and a fine bubble generation portion disposed between the inlet and the outlet. The fine bubble generation portion may include a venturi portion including a diameter-reducing flow path and a diameter-increasing flow path, wherein a flow path diameter of the diameter-reducing flow path reduces from upstream to downstream, and the flow path diameter of the diameter-increasing flow path increases from upstream to downstream, a discharging flow path configured to discharge the gas-dissolved water, which flowed out of the venturi portion, out of the fine bubble generation portion; and a recirculation flow path connecting a midstream of the outflow path and the venturi portion.

An aeration apparatus including a tank defining a cavity to receive a liquid, at least one aerator positioned within the tank, and a plenum connected to a bottom surface of the tank and in fluid communication with the at least one aerator, in which an air flow is directed from the plenum into the at least one aerator to deliver air to the liquid in the tank to oxidize the fluid.

A flotation cell for treating particles suspended in slurry and for separating the slurry into an underflow and an overflow is disclosed. The flotation cell includes a flotation tank including a center, a perimeter, a bottom, and a side wall; and a launder and a launder lip surrounding the perimeter of the flotation tank. The flotation tank further includes blast tubes for introducing slurry infeed into the flotation tank. A flotation line, as well as a use of the flotation line is also disclosed.

A bubble generation device includes: a metallic narrow tube (10) through which water passes; and a pump that pressure-feeds the water containing a gas component into the metallic narrow tube (10). A drawer (11) in which a path through which the water passes is narrower than the front and the rear thereof in the flow direction of the water is disposed on the inside of the metallic narrow tube (10). The drawer (11) has the rectangular cross section orthogonal to the flow direction. The gas component contained in the water is dissolved in the water by pressure-feeding the water to the drawer (11), bubbles are evolved due to a decrease in pressure in the drawer (11), turbulent flow is generated in the water in the drawer (11) to crush bubbles in the water by the shearing force thereof, and bubbles are crushed by a shock wave caused by transonic flow occurring in the water that has exited from the drawer (11).

Provided is an ultrafine bubble generation device for aquaculture or wastewater treatment with which it is possible to efficiently cause ultrafine bubbles to be dissolved or to coexist, and to increase the concentration of a gas in the liquid. An ultrafine bubble generation device for aquaculture or wastewater treatment provided with a channel for channeling a liquid, a compression device for pumping a gas into the channel, and a bubble generation medium for releasing the gas pumped by the compression device as ultrafine bubbles into the liquid in the channel, wherein the bubble generation medium is formed from a carbon-based porous material and is disposed so as to be horizontal or below horizontal with respect to the direction of flow of the liquid in the channel.

A device (1) for dissolving a gas (G) in water (W) is provided, and includes a housing (100) configured to be submerged into the water (W) with the housing (100) having at least one water inlet (101), a gas inlet (102) and at least one water outlet (103) for discharging gas enriched water out of the housing (100), a pump (5) in fluid communication with the at least one water inlet (10) for sucking water (W) from a surrounding of the housing (100), the pump configured to generate a main water stream (S′), and means for injecting the gas (G) supplied via the gas inlet (102) into the main water stream (S′). The device (1) includes a probe (6) configured to measure a concentration of the gas dissolved in water, and the probe (6) is arranged in the housing (100) of the device (1).

Provided are: a microbubble generation device utilizing a swirling flow generated by injecting of a pressurized liquid; a microbubble generation method capable of generating a large amount of bubbles; and a shower apparatus and an oil-water separation apparatus having said microbubble generation device. This microbubble generation device comprises: a cylindrical or conical cylinder with a gas-liquid swirling chamber therein; a gas-liquid discharge inlet provided on one end of the cylindrical or conical cylinder; and a liquid supply cylinder and a gas supply cylinder for introducing a liquid and a gas into the gas-liquid swirling chamber. For the gas-liquid discharge outlet, a plurality of small cylindrical through-holes or a plurality of small recessed parts with a circular cross-section and at least a semicircular circumferential length, are respectively provided in the wall of a closed end at one end of the cylindrical or conical cylinder or on the circumferential surface of the inner wall of an open end at one end thereof.

A fine-bubble mixed liquid producing apparatus 1 includes a reservoir 4 and a bubble feeding means 6 for feeding bubbles to a liquid L stored in the reservoir 4, wherein the bubble feeding means 6 includes a rotary cylinder 20 having an emitting part 22 on the outer circumferential surface, the emitting part 22 for being rotationally driven by a drive means 10, a circulating means 40 for drawing out the liquid L stored in the reservoir 4 and feeding the liquid L from the emitting part 22 to the reservoir 4, and a gas-liquid mixing part 50 for mixing bubbles with the liquid L circulated by the circulating means 40. This apparatus enables a fine-bubble mixed liquid to be efficiently produced.

A microbubble device controller includes a box, and a first water pipe, a gas pipe and a bypass pipe installed in the box. The first water pipe is connected to a pump and has a first electromagnetic control valve to open or close the first water pipe. The gas pipe is connected to a gas source and the pump, and has a second electromagnetic control valve to open or close the gas pipe. The bypass pipe is connected to the first water pipe and has a pressure switch in telecommunication connection with the second electromagnetic control valve. The first electromagnetic control valve controls the first water pipe to be in the high flow state or a closed state to affect the bypass pipe. When the bypass pipe is in a high pressure state, the second electromagnetic control valve opens the gas pipe, or closes the gas pipe otherwise.

Provided is a method for manufacturing a microbicide having high microbicidal performance for eradicating microbes. This method for manufacturing a microbicide comprises: a step for preparing an inorganic aqueous solution containing an inorganic component having seawater as a raw material thereof, an ozone mixing step for mixing ozone into the inorganic aqueous solution, and a stirring step for stirring the inorganic aqueous solution mixed with ozone and passing through a bubble generation nozzle; wherein, the temperature of the inorganic aqueous solution in the ozone mixing step and the stirring step is 0 C. to 30 C., and when the amount of inorganic aqueous solution treated in the ozone mixing step and the stirring step is defined as X liters and the treatment rate of the ozone mixing step and the stirring step is defined as Y liters/minute, then the microbicide is manufactured by alternately repeating the ozone mixing step and the stirring step for A.Math.X/Y minutes (where A is 30 or more).