Abstract: The present invention is an aquifer storage and recovery system using a natural coagulant, in which in purifying raw water through aquifer storage and recovery, assimilable organic carbon (AOC) included in the raw water is effectively removed using a natural coagulant produced in the aquifer storage and recovery process, thereby reducing the time required to purify raw water by aquifer storage and recovery.

Abstract: The present invention is an aquifer storage and recovery system using a natural coagulant, in which in purifying raw water through aquifer storage and recovery, assimilable organic carbon (AOC) included in the raw water is effectively removed using a natural coagulant produced in the aquifer storage and recovery process, thereby reducing the time required to purify raw water by aquifer storage and recovery.

Abstract: Disclosed are apparatus and method for alternative aeration-effluent wastewater treatment using a ceramic membrane, which allows the biological treatment to be performed sufficiently in an intermittent aeration tank by combining an anaerobic tank with a plurality of intermittent aeration tanks and selectively changing an inflow path of influent water according to an operation status of the intermittent aeration tanks. The present disclosure is directed to providing an apparatus and method for alternative aeration-effluent wastewater treatment, which allows the aeration and treated water to continuously discharge through two intermittent aeration tanks by independently forming an air injection line and a treated water discharge line at a ceramic membrane provided in each intermittent aeration tank.

Abstract: Disclosed herein are an apparatus and method for cultivating microalgae using effluent from sludge treatment. The apparatus includes an advanced sewage treatment apparatus, a sludge treatment apparatus and a microalgae cultivation apparatus, the sludge treatment apparatus including: a first aerobic reactor which is operated under aerobic conditions and serves to ferment sludge; a second aerobic reactor which is operated in a state in which air is injected in an amount larger than that in the first aerobic reactor, and serves to increase the fermentation activity of microorganisms in the sludge and degrade the sludge; a membrane bio-reactor (MBR) which serves to receive effluent from the second aerobic reactor and biologically remove high-concentration organic matter from the effluent by the action of aerobic microorganisms while removing total suspended solids using a membrane, wherein the effluent discharged from the MBR reactor is supplied to the microalgae cultivation apparatus.

Abstract: Disclosed herein are an apparatus and method for reducing nitrate using iron-oxidizing microorganisms, which can easily reduce nitrate using iron-oxidizing microorganisms. The apparatus includes: a nitrate-reducing reactor which is operated under anaerobic conditions and provides a space for reduction of nitrate; and an iron-oxidizing microorganism provided in the nitrate-reducing reactor, wherein the iron-oxidizing microorganism releases divalent iron (Fe2+), the released Fe2+ is converted to Fe3+ by microbial oxidation under anaerobic conditions while releasing an electron, and the released electron is used in the reduction of nitrate into nitrogen gas by the iron-oxidizing microorganism.

Abstract: A sludge treatment apparatus includes an aeration tank serving to degrade microorganisms other than Bacillus sp. in sludge to produce organic matter to thereby activate Bacillus sp.; a poor aeration tank serving to reduce the activity of microorganisms in the sludge; a spore-forming tank operated under oxygen-free conditions and serving to induce the degradation and death of microorganisms remaining in the sludge while inducing the formation of spores of Bacillus sp.; a Bacillus sp.-activating reactor provided in an internal return line extending from the spore-forming tank to the aeration tank and serving to supply minerals to the sludge returned from the spore-forming tank to activate spore-type Bacillus sp.; and a sedimentation tank serving to induce the gravity sedimentation of the sludge discharged from the spore-forming tank to separate the discharged sludge into a supernatant and a concentrated sludge.

Abstract: Disclosed are apparatus and method for alternative aeration-effluent wastewater treatment using a ceramic membrane, which allows the biological treatment to be performed sufficiently in an intermittent aeration tank by combining an anaerobic tank with a plurality of intermittent aeration tanks and selectively changing an inflow path of influent water according to an operation status of the intermittent aeration tanks. The present disclosure is directed to providing an apparatus and method for alternative aeration-effluent wastewater treatment, which allows the aeration and treated water to continuously discharge through two intermittent aeration tanks by independently forming an air injection line and a treated water discharge line at a ceramic membrane provided in each intermittent aeration tank.