10371results about "Treatment using aerobic processes" patented technology

The present invention relates to an integrated closed loop system for aquaculture in at least one culturing tank and using continuous bioreactor technology for the biological treatment and removal of organic material, nitrogen and phosphorous, comprising: an integrated, partially or wholly closed loop system for waste water treatment, where the water contains nitrogen containing compounds and / or substances, comprising at least one production unit of such nitrogen containing compounds and / or substances and using continuous bioreactor technology for the biological treatment and removal of organic matter, nitrogen and phosphorous from the said water at continuous flow, comprising: a) at least one suspended carrier bioreactor for bacterial growth under anoxic conditions to cause anaerobic denitrification, with one or several compartments, preceding b) at least one suspended-carrier bioreactor for bacterial growth under oxic conditions to cause aerobic nitrification, c) the denitrification taking place after the production unit, and d) the nitrification taking place prior to the production unit in a by-pass mode as part of the continuous flow.

Contaminated wastewaters comprising biochemical oxygen demand (BOD), nitrogen and phosphorus are treated by an activated sludge process. The process utilizes an activated sludge tank, a solid-liquid separator, and a bioreactor to significantly reduce, or eliminate, waste activated sludge (WAS) within a sludge stream. A sidestream reactor is employed downstream from the bioreactor to remove soluble phosphates left in the sludge stream by the low WAS process. Within the sidestream reactor, a source of multivalent metal ions is added to a slightly alkaline sludge stream to precipitate the phosphates. The solid phosphates have a specific gravity higher than that of the organic matter in the sludge stream and may be separated from the sludge stream based upon differential settling velocity.

A wastewater treatment system is provided that includes first and second reactors, each operative to nitrify or denitrify wastewater contained therein. Downstream from the first and second reactors is a membrane reactor that operates under aerobic conditions and includes one or more submersed membranes for separating solids. Extending between the membrane reactor and each of the first and second reactors is a return activated sludge line with appropriate controls for permitting return activated sludge to be directed to one of the reactors at a time. To nitrify and denitrify wastewater, a wastewater influent stream is alternatively directed to the anoxic reactors which are alternatively operated under aerobic and anoxic conditions so as to nitrify or denitrify the wastewater contained therein. To reduce or minimize the dissolved oxygen return from the membrane reactor to the first and second reactors, the flow of return activated sludge is controlled such that generally return activated sludge is returned to the reactor operating under aerobic conditions.

Disclosed are a membrane coupled activated sludge method and apparatus operating anoxic / anaerobic processes alternately for removal of nitrogen and phosporus, wherein nitrogen and phosphorous together with organics in the sewage, wastewater, filthy water etc. can be simultaneously removed with an economic and efficient manner, an operation thereof is easy and efficient, a capacity thereof is high and the method is economic due to the reduced operating costs with performing measurement and control of a recycle rate, a recycle time of alternate operation of the anoxic and anaerobic process, an amount of sludge, an amount of aeration and an operation of a blower for an intermittent membrane cleaning.

Methods and apparatus employing membrane filtration in biodegradation processes for treatment of wastewater are described. A bioreactor system is described having an equalization system, a membrane bioreactor system, and a controller. Aeration systems for a membrane bioreactor, such as a mixer, and an ultrafilter subsystem are also described, as is a rotary membrane ultrafilter.

Removal of biological nutrients from a wastewater yielding a low phosphorous (e.g., less than 0.25 mg / L) output includes providing a serial multistage bioreactor containing activated sludge having in hydraulic series an anaerobic zone and a downstream aerobic zone, with each zone having an upstream inlet and a downstream outlet. The wastewater is provided to the anaerobic zone inlet. A quantity of chemical sufficient to precipitate soluble and particulate phosphorous is added to the downstream aerobic zone in an amount sufficient to yield a low phosphorous output. Treated water is separated from the activated sludge and precipitated phosphorous and a return activated sludge separated from the treated water is recycled to the anaerobic zone.

This is a method of batch-continuous operation for treatment and separation of liquid-solid mixtures in a reactor with reactive solids comprising steps of continuously feeding the liquid in the reactor, contacting (possibly, mixing) liquid with the solids in at least a portion of the reactor, periodically separating the liquid from the solids in unmixed, or predominantly unmixed, portion of the reactor, discharging at least a portion of the separated liquid from the reactor, and retaining the separated solids in the unmixed portion of the reactor, and periodically resuspending the solids in the unmixed portion of the reactor and transferring the resuspended soilds into the portion of the reactor for contacting liquid with the solids. The contacting and / or mixing of the liquid with the solids in the mixed portion of the reactor can be continuous or periodic mixing. The unmixed zone differs from the quiescent zone in conventional clarifiers. It is a flow-through zone with a noticeably high velocity of flow as in aeration tanks of biological treatment systems. The retention time in unmixed zones is much shorter than in clarifiers. The method and apparatus can be used to treat water and wastewater, and in various chemical, biochemical, and pharmaceutical processing operations.

The invention provides a zero-discharge treatment method of salt-containing organic wastewater. The method comprises the following steps that biochemical treatment and filtering treatment are performed on wastewater; then, membrane concentration is performed; pure-water-producing high-organic-matter-content membrane concentration concentrated water and optional low-organic-matter-content membrane concentration concentrated water are obtained; the high-organic-matter-content membrane concentration concentrated water is used for high-grade oxidation treatment; high-grade oxidation produced water is used for regulation treatment to obtain high-grade oxidation outlet water; the obtained high-grade oxidation outlet water is subjected to evaporation treatment; or the obtained high-grade oxidation outlet water and the low-organic-matter-content membrane concentration concentrated water are mixed under the condition that the low-organic-matter-content membrane concentration concentrated water exists in the step, and then, the evaporation treatment is carried out; external discharge concentration liquid of an evaporator and / or high-salt-content high-organic-matter-content wastewater discharged during the tank brushing of the evaporator are conveyed back into a high-grade oxidation treatment unit; after the liquid is mixed with the high-organic-matter-content membrane concentration concentrated water, the high-grade oxidation treatment is carried out. The wastewater treatment method is stable and reliable; the long-period and stable operation of an evaporation system can be ensured; the zero discharge of the industrial wastewater is realized.