A header-equipped air diffusion device can sufficiently suppress the intrusion of sludge into the air diffusion device from the header and allow stable operation even with repeated operating and stopping, and a membrane separation activated sludge device. The header-equipped air diffusion device can include an air diffusion device and a header which are immersed in water to be treated. The header includes an air storage unit, on the lower end of which is formed an inlet for the water to be treated, and an air supply part and an air sending part provided on the upper section of the air storage unit. The air sending part and a horizontal tube of the air diffusion device are connected, the air sent from the header is diffused by the air diffusion device, and an air sending of the air sending part in the air storage unit is positioned above an air supply port of the air supply part.

A membrane filter module configured to treat a liquid contained in a tank at an ambient pressure. The module may have a header, with a bundle containing a plurality of substantially vertical hollow fiber membranes, wherein a lower end of each hollow fiber membrane is fixed in the header. The module may also have a gasification device adapted to periodically generate a gaseous bubble and configured to release the gaseous bubble within the bundle. The module may further have an enclosure that substantially surrounds the bundle that extends from a lower region to an upper region of the membrane bundle, wherein the enclosure is configured to retain the liquid introduced into the enclosure such that the liquid surrounds the membrane bundle. The gaseous bubble has a cross-sectional area that corresponds with a cross-sectional area of the enclosure, such that the cross-sectional area of the gaseous bubble occupies substantially the entire cross-sectional area of the enclosure as it flows along the bundle.

A water treatment control system includes an aerobic tank in which aerobic treatment is carried out, an aerobic tank aeration device that aerates to-be-treated water in the aerobic tank, a membrane filtration tank including a separation membrane that filters the to-be-treated water treated in the aerobic tank, a membrane filtration tank measurement instrument that measures the ammonia concentration of the to-be-treated water in the membrane filtration tank, as a membrane filtration tank ammonia concentration measurement value, and an aerobic tank aeration air volume calculation device that sets the aerobic tank aeration air volume of the aerobic tank aeration device on the basis of the membrane filtration tank ammonia concentration measurement value.

A bioreactor has a biofilm that receives a gas through a supporting membrane and another biofilm attached to an inert support. The first biofilm is aerated through the membrane and provides nitrification. The other biofilm has an anoxic or anaerobic zone and provides denitrification. A module useful in the bioreactor has cords potted in at least one potting head. Optionally, some or all of the cords have a gas transfer membrane. The module may provide inert supports, active gas transfer supports or a combination of both types of support. Multiple modules may be assembled together into a cassette, the cassette providing inert supports, active supports or a combination. The module or cassette may have an aerator for mixing or biofilm control.

A process for treating domestic wastewater may include directing wastewater into a tank containing a membrane filter and mixed liquor. The process may include recirculating wastewater and mixed liquor from a top end of the tank into a bottom end of the tank via a recirculation conduit. The process may include introducing a flow of wastewater and mixed liquor from the recirculation conduit into an aeration device and drawing ambient air into the aeration device using the flow of wastewater and mixed liquor from the recirculation conduit. The process may also include drawing wastewater and mixed liquor proximately surrounding the aeration device into the aeration device using the flow of wastewater and mixed liquor from the recirculation conduit. The process may include aerating a mixture of wastewater and mixed liquor with the ambient air below the membrane filter.

The present disclosure is directed toward membrane biofilm reactors primarily comprising microorganisms that produce chemical fuel products or precursors thereof. Reactors of the present disclosure can primarily comprise acetogens, a methanotrophs, and/or Methanosarcina acetivorans.

This water treatment system is provided with: a reverse osmosis membrane device; a biofilm treatment device that has a carrier, on a surface of which is formed a biofilm, and that treats water to be treated before the water to be treated is transmitted through the reverse osmosis membrane device; and at least one of a water to be treated stoppage period circulation means and a water to be treated stoppage period supply means that are driven when the intake of new water to be treated is stopped. The water to be treated stoppage circulation means supplies and circulates water to be treated from a water to be treated discharge outlet side of the biofilm treatment device to a water to be treated supply port side. The water to be treated stoppage period supply means supplies new water to be treated to the biofilm treatment device.

This water treatment system is provided with: a reverse osmosis membrane device; a biofilm treatment device that has a carrier, on a surface of which is formed a biofilm, and that treats water to be treated before the water to be treated is transmitted through the reverse osmosis membrane device; and at least one of a water to be treated stoppage period circulation means and a water to be treated stoppage period supply means that are driven when the intake of new water to be treated is stopped. The water to be treated stoppage circulation means supplies and circulates water to be treated from a water to be treated discharge outlet side of the biofilm treatment device to a water to be treated supply port side. The water to be treated stoppage period supply means supplies new water to be treated to the biofilm treatment device.

This disclosure relates to an apparatus and method for analyzing an influence variable on membrane fouling of a seawater desalination system, wherein influence variables other than variables having a low degree of influence, among variables affecting the membrane, are selected, and the influence thereof on membrane fouling is used to derive an equation. The apparatus includes a variable storage unit configured to store variables affecting membrane fouling of a seawater desalination system, a dominant variable selection unit configured to select at least one dominant variable among the variables through at least one algorithm, and an equation derivation unit configured to derive a specific equation based on a correlation between the selected dominant variable and the membrane fouling.

A membrane biofilm reactor including a vessel defining a volume is disclosed. The reactor also typically includes a first and second plurality of hollow fiber membranes. Each hollow fiber membrane generally has an outer surface and a lumen, and is located within the volume. The reactor further preferably includes a first and second gas feedstock. The first gas feedstock is provided through a first inlet in fluid communication with the lumens of the first plurality of hollow fiber membranes. The second gas feedstock is provided through a second inlet in fluid communication with the lumens of the second plurality hollow fiber membranes. Finally, the reactor also typically includes a biofilm formed on the outer surface of the hollow fiber membranes and made up of methanotrophs, Methanosarcina acetivorans, or both. The first gas feedstock is preferably different from the second gas feedstock.