A redox water treatment method comprises first determining the composition of water and whether water treatment requires either oxidation or reduction, or both to optimize nitrogen removal by a bioreactor. Sulfur dioxide (SO.sub.2) is injected into the water to be treated to provide H.sup.+, SO.sub.2, SO.sub.3.sup.=, HSO.sub.3.sup.−, dithionous acid (H.sub.2S.sub.2O.sub.4), and other sulfur intermediate reduction products forming a sulfur dioxide treated water, which behaves either as a reducing agent or an oxidizing agent depending on the strength of the acid concentration, which alters sulfurous acid from a reducing agent to a more powerful oxidizing agent.

Provided are systems and methods for treating wastewater with a continuous-process mobile station. The mobile station may include one or more mobile units configured to receive a feed of wastewater. The one or more mobile units may include: a mobile ozonation unit configured to treat the received feed of wastewater with ozone gas to breakdown impurities in the wastewater, a pH control unit may be configured to raise pH of the treated wastewater, a mobile electrocoagulation unit configured to separate solids and metals from the treated wastewater, a mobile flocculation unit configured to cause suspended particles to form flocs and to remove the flocs from the received treated water.

There are provided processes for treating wastewater. The processes can comprise treating a mixture comprising the wastewater and an activated sludge, in a single reactor, with an electric current having a density of less than about 55 A/m.sup.2, by means of at least one anode and at least one cathode that define therebetween an electrical zone for treating the mixture; exposing the mixture to an intermittent ON/OFF electrical exposure mode to the electric current in which an OFF period of time is about 1 to about 10 times longer than an ON period of time; and maintaining an adequate oxidation-reduction potential in the single reactor. Such processes allow for substantial removal of carbon, nitrogen and phosphorus from the wastewater in the single reactor of various forms and for obtaining another mixture comprising a treated wastewater and solids.

A batch reactor includes a first portion, a second portion, a first drainage tank, a second drainage tank, and a first flow control mechanism. The first portion includes a first chamber, a second chamber, and a third chamber in fluid communication with one another configured for a flow of at least one biomaterial therethrough. The second portion includes a first chamber and a second chamber in fluid communication with one another configured for a flow of the least one biomaterial therethrough. The first drainage chamber is in fluid communication with the first and second chambers. The second drainage chamber is in fluid communication with the third chamber of the first portion and the second chamber of the second portion. The first flow control mechanism is disposed between the third chamber of the first portion and the first chamber of the second portion.

A method for increasing the quantity of dissolved oxygen in water includes addition of an oxidant to the water to increase the oxidation-reduction potential (ORP) of the water to between about 400 and 850 mV, followed by electrolysis to generate oxygen gas. The voltage applied to the electrolytic cells during electrolysis is less than 300 mV. The dissolved oxygen content of the water exiting the electrolytic cell is about 90% of saturation to super saturation.

The present invention relates to a fresh water generation method including: feeding raw water or pretreated water thereof as feed water into a semipermeable membrane module in a pressurized state using a booster pump, thereby separating the feed water into a concentrate and a permeate having a low concentration, in which a scale inhibitor having a reducing function is dosed intermittently or continuously upstream from the semipermeable membrane module, thereby inhibiting scale generation and maintaining an oxidation-reduction potential of at least either the feed water or the concentrate to a threshold value or lower.

A transportable system for creating an oxidation reduction potential (ORP) in water employs a pipe assembly for in-line mixing. The pipe assembly includes a first flow path for water to flow through. The first flow path includes one or more ozone intake ports that are fluidically coupled to one or more ozone output ports of an ozone supply unit. The pipe assembly further includes a second flow path fluidically coupled in parallel with the first flow path. The second flow path includes a control valve that selectively permits a portion of the water to flow through the second flow path to produce a negative pressure in the first flow path so that ozone is drawn into the first flow path through the one or more ozone intake ports and mixed into the water flowing through the first flow path.

A method enhancing biological digestion of wastewater sludge is provided. The method uses chlorine dioxide to accelerate and improve the efficiency of aerobic or anaerobic digestion.

A circulation type aquaculture method and a circulation type aquaculture apparatus which treat and remove ammonia harmful to fishes/shellfishes. The method includes a first step of finding an ammonia decomposition rate upon preliminarily treating cultivation water by using ozone or hypochloric acid so as to set a target remaining amount of ammonia after the decomposing treatment, a second step of finding the amount of ammonia in cultivation water so as to calculate a treating period of time required for reducing the amount of ammonia to the target remaining amount of ammonia based upon the ammonia decomposition rate of the first step, a third step of treating the cultivation water using ozone or hypochloric acid during the treating period of time calculated in the second step so as to treat and decompose ammonia in the cultivation water and a fourth step of returning the cultivation water to the aquaculture tank.

The invention comprises a control system for monitoring and operating an existing supply water pre-treatment system for supplying de-chlorinated water to dialysis purification systems. The invention includes a controller and an operator interface for programming and interacting with said control systems. The invention further includes an injection assembly having a flow turbine sensor, a reducing agent injector, and an ORP/pH sensor for monitoring and controlling ORP/pH levels of said supply water.