The systems and methods disclosed herein provide for the efficient generation of fine bubbles. In particular, systems and methods for use in bioreactors are disclosed herein providing a superior means to produce useful fermentation products by the biological fermentation of fine bubble waste substrates injected into a liquid broth containing a microorganism culture.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.

A method the filtering a liquid in a membrane filter immersed in the liquid and including membranes, the method including introducing a gas through a gas introduction device into a base of the membrane filter in successive pulses so that the membranes are cleaned wherein the gas introduction device includes a liquid flow channel which vertically penetrates a gas collection cavity and admits the liquid into a bottom of membrane filter; and initially filling a gas volume arranged below a free surface of the liquid and defined in a downward direction by an enclosed level of the liquid with the gas wherein the gas simultaneously displaces the liquid top down from a gas lifting channel until the enclosed level of the liquid drops below an inlet cross section of a gas flow out channel; and subsequently.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.

A method for introducing a gas into a liquid, the method including filling a gas volume enclosed below a free surface of the liquid and defined in a downward direction by an enclosed level of the liquid with the gas in sequential pulses wherein the gas simultaneously displaces the liquid top down from a gas lifting channel until the enclosed level of the liquid drops below an inlet cross section of a gas flow out channel; subsequently flowing the gas out of the gas volume downward through the gas lifting channel, a deflection portion adjoining at a bottom of the gas lifting channel, in upward direction through the inlet cross section and through the gas flow out channel adjoining the inlet cross section at a top to the free surface.

A method the filtering a liquid in a membrane filter immersed in the liquid and including membranes, the method including introducing a gas through a gas introduction device into a base of the membrane filter in successive pulses so that the membranes are cleaned wherein the gas introduction device includes a liquid flow channel which vertically penetrates a gas collection cavity and admits the liquid into a bottom of membrane filter; and initially filling a gas volume arranged below a free surface of the liquid and defined in a downward direction by an enclosed level of the liquid with the gas wherein the gas simultaneously displaces the liquid top down from a gas lifting channel until the enclosed level of the liquid drops below an inlet cross section of a gas flow out channel.

The purpose of the present disclosure is, in a bubble generating device provided with a bubble generating unit for generating minute bubbles in water flowing through the inside of the cylindrical main body unit, to improve the bubble generating efficiency of the bubble generating unit. Provided is a bubble generating device provided with a cylindrical main body unit and a bubble generating unit disposed within the main body, wherein: the bubble generating unit is provided with slits extending radially centered on one point within the main body unit in a cross-sectional plane of the main body unit, and a column part protruding from the inner peripheral surface of main body unit and formed on the peripheral edge of the slits; and the amount of protrusion of the column part is gradually reduced toward the upstream side from the peripheral edges of the slits, and the column part has a recessed part formed on the downstream surface.