A system for reducing emission of nitrous oxide during sewage treatment, including: a regulating pool, a first aerobic constructed wetland, an anoxic pool, and a second aerobic constructed wetland. The water outlet of the regulating pool is connected to the water inlet of the top of the first aerobic constructed wetland via a pipe and a first control valve. The first aerobic constructed wetland includes sequencing batch constructed wetlands arranged in parallel. A branch pipe and a second control valve are disposed on the pipe between the regulating pool and the first aerobic constructed wetland. The outlet of the branch pipe and the water outlet of the first aerobic constructed wetland are combined together and connected to the water inlet of the bottom part of the anoxic pool. The anoxic pool is an upward flow biological filter.

A system and method for treating wastewater includes two or more biological reaction zones separated by chamber walls. The system and method for treating wastewater includes static recycle of a mixed liquor from a second biological reaction zone to a first biological reaction zone.

A system and method for treating wastewater includes two or more biological reaction zones separated by chamber walls. The system and method for treating wastewater includes static recycle of a mixed liquor from a second biological reaction zone to a first biological reaction zone.

A sludge treatment system with sludge drying acceleration function includes at least one sedimentation tank, at least one sludge pipe, and at least one group of hydroponic plant. The at least one sedimentation tank is disposed at the downstream of a reservoir. The at least one sludge pipe is disposed in the at least one sedimentation tank for leading the sludge into the at least one sedimentation tank through a leading method, such that the sludge in the at least one sedimentation tank is divided into a water layer and a mud layer. The at least one group of hydroponic plant is planted in the water layer of the at least one sedimentation tank, such that the growth of the at least one group of hydroponic plant accelerates the sludge drying process in the sedimentation tank.

A sludge treatment system with sludge drying acceleration function includes at least one sedimentation tank, at least one sludge pipe, and at least one group of hydroponic plant. The at least one sedimentation tank is disposed at the downstream of a reservoir. The at least one sludge pipe is disposed in the at least one sedimentation tank for leading the sludge into the at least one sedimentation tank through a leading method, such that the sludge in the at least one sedimentation tank is divided into a water layer and a mud layer. The at least one group of hydroponic plant is planted in the water layer of the at least one sedimentation tank, such that the growth of the at least one group of hydroponic plant accelerates the sludge drying process in the sedimentation tank.

Present invention relates to a method and apparatus for purification of water, said method comprises the steps of feeding the water into a reactor (4) through one or more inlet tubes (1) or inlet zones and feed water an substrate through carrier elements for bio film (5) which have a large protected surface (>200 m2/m3 carrier elements) and large pore volume (>60%), and that the carrier elements are fluidized for the removal of waste sludge, wherein the ratio of charge of the elements (5) by normal duty corresponds to an amount corresponding to 90%-100%, more preferred 92%-100%, and most preferred 92%-99% of the vet volume of the reactor (4), said carrier elements (5) is kept substantially at rest or hindered movement between the times surplus sludge is removed, and that the carrier elements being fluidised for removal of surplus sludge, said carrier elements (5) having a specific gravity in the area of 0.8-1.4, more preferred 0.90-1.1 and most preferred 0.93-0.97, and feed the treated water to one or more outlet zones (7) and one or more outlet tubes (2). The invention also comprises a reactor for performing the method.

A bioreactor for anaerobic, aerobic and anoxic digestion of organic matter from wastewater, having a bottom anaerobic zone where the wastewater is fed where anaerobic bacteria produces biogas and the sludge produced is deposited on the bottom and subsequently extracted. An anoxic middle zone contains denitrifying bacteria which converts nitrates to nitrogen, and an aerobic zone at the upper part where at least one biological contact rotor is disposed, which degrade organic matter remaining in the water. The growth of nitrifying bacteria converts ammonia nitrogen into nitrites and nitrates. The tank has a plurality of rhomboids for biogas, sludge and scum collection that join together form a intermediate polyhedral separator panel. The rhomboids joined together define conical collectors with connecting nozzles of ducts from a capture and conduction network of biogas and funnel-shaped manifolds with connecting nozzles of ducts that define a capture and conduction network of sludge and scum.

A process approach allows economical self-sustained operation of single vessel biotreatment systems for municipal wastewater treatment. The daytime solar powered treatment process is changed during darkness periods to operate the biotreatment system without electric grid powering.

A method of wastewater treatment using a membrane bioreactor, including: controlling aeration to enable a dissolved oxygen concentration to be 0 to 1.5 mg/L, and keeping the integrated reaction vessel under a facultative environment. A wastewater treatment system by the membrane bioreactor without physical area division includes a reaction vessel, a membrane separation system, a water production system, and an aeration system. The membrane separation system is disposed inside the reaction vessel. The water production system communicates with the membrane separation system to pump filtrate out of the membrane separation system. The aeration system is employed to aerate the reaction vessel and the membrane separation system.

A screw-type separation device 1 includes a casing 10 including an object discharging port and discharging an object A having been dehydrated, and a separated liquid discharging port; a screw shaft provided inside the casing and extending in an extending direction that is a direction from the one end part to the other end part; a first screw blade extending spirally on an outer peripheral surface of the screw shaft; and a second screw blade extending spirally on the outer peripheral surface of the screw shaft such that a predetermined gap is formed with respect to the first screw blade in the extending direction. A groove is formed on an inner peripheral surface of the casing.