A system for treating a source of water contaminated with PFAS is disclosed. The system includes a PFAS separation stage having an inlet fluidly connectable to the source of water contaminated with PFAS, a diluate outlet, and a concentrate outlet and a PFAS elimination stage positioned downstream of the PFAS separation stage and having an inlet fluidly connected to an outlet of the PFAS separation stage, the elimination of the PFAS occurring onsite with respect to the source of water contaminated with PFAS, with the system maintaining an elimination rate of PFAS greater than about 99%. A method of treating water contaminated with PFAS is also disclosed. The method includes introducing contaminated water from a source of water contaminated with a first concentration of PFAS to an inlet of a

PFAS separation stage, treating the contaminated water in the PFAS separation stage to produce a product water substantially free of PFAS and a PFAS concentrate having a second PFAS concentration greater than the first PFAS concentration, introducing the PFAS concentrate to an inlet of a PFAS elimination stage; and activating the PFAS elimination stage to eliminate the PFAS in the PFAS concentrate. A method of retrofitting a water treatment system as described herein is also disclosed. The method includes providing a PFAS elimination module as described herein and fluidly connecting the PFAS elimination module downstream of a PFAS separation stage.

A combined water aeration and filtration unit (WAFU), having a tank with a vent section at a top of said WAFU and above an aeration section above a filtration section at a bottom of said WAFU. The vent section has one or more demisters and one or more vents for detraining water and providing a dry air exit from said WAFU. The air section has a water inlet ending in a spray nozzle near the top of the aeration section to turn incoming dirty water into water droplets and a forced air blower on a side or top of the aeration section for blowing air through said water droplets in rate sufficient to remove volatile organic compounds and precipitate manganese and iron. The aeration section also has one or more annular rings or partially annular baffles on an inside wall of the tank to force water from said inside wall into an interior of the tank. Thus, no water escapes aeration. A backwash collection trough and backwash water outlet are positioned above the filtration section for removing dirty backwash water from the unit. The filtration section has one or more filters therein and a drain and clean water outlet near its bottom for egress of clean water from said WAFU.

A control system includes one or more levels of control of power and energy. At one level, a first controller optimally divides power between two or more processes, to maximize instantaneous production, for a given amount of currently available power. In the case of EDR desalination, electric power is optimally divided between ion exchange membranes and pumps to maximize instantaneous production of desalinated water for a given amount of available electric power. Optionally, at another level, a second controller divides time-varying power between the processes fed by the first level controller and an energy storage unit, based on a prediction of future power availability and a function. In the EDR case, power generated by a photovoltaic array is divided between the EDR desalination process and a battery, based on a prediction of future PV power availability and a function, to ensure reliable water production in the future.

Disclosed herein is a device and methods for enhancing oil separation from produced water. One such method includes mixing a multiphase fluid having at least a water phase and an oil phase with a flotation gas, according to at least one operating condition, so as to produce an enhanced multiphase fluid having bubbles of the flotation gas therein. The oil phase is then separated from the water phase using a separator. At least one property associated with the enhanced multiphase fluid is monitored. The operating condition is adjusted as a function of the monitored property so as to increase a percentage of the oil phase separated from the water phase by the separator over a percentage of the oil phase that would be separated from the water phase without adjustment of the operating condition.

Systems and methods for monitoring and/or controlling anti-scalant concentration. The systems may include components that form an automated control loop. The methods may be online methods that allow the concentration of an anti-scalant to be monitors in a fluid treatment system, such as a water treatment system.

Methods and systems for the controlled production of aqueous halogen solutions with varying compositions are disclosed. According to an embodiment, aqueous solutions of hypochlorite ions are modified through the sequential addition of pH adjusting chemicals, non-chloride halide ions, and halogen stabilizing compounds. Sensors, for measuring physical and chemical properties of the solutions as they change due to the impact of the various chemical reactions, are linked to a control system which, in turn, can control the input of one or more chemicals. The control system facilitates the production of a solution with desired characteristics in terms of pH, specific halogen composition, degree of halogen stabilization, and limiting the production of undesired by products such as bromate ions.

A flow channel switching system (1, 1′) including: a first on-off valve (10) which is disposed between a merging portion (6) and a branching portion (5) and in a raw water path (4); a second on-off valve (11) which is disposed in an outward path for raw water (7); and a sensor (13) that measures a state of water flowing through the raw water path, in which control is performed so as to open the second on-off valve and close the first on-off valve if a signal indicating that water is flowing in the raw water path is received from the sensor, then a signal indicating that no water is flowing in the raw water path is received, and then, within a predetermined time period, a signal indicating that water is flowing again in the raw water path is received.

A total biological count associated with treated water produced by a wastewater treatment system may be monitored online in a decentralized non-potable water system. Preventative and/or corrective action can be taken in response to a deviation from a predetermined threshold level.

A resistivity regulating apparatus includes: a gas dissolving device that causes a regulating gas to dissolve in a liquid targeted for resistivity regulation to generate a treated liquid in which the regulating gas is dissolved in the liquid, the regulating gas being used to regulate a resistivity of the liquid; and a buffer tank to which the treated liquid discharged from the gas dissolving device is fed.

A method of providing sustained odor control in an extended sewer line is disclosed. The method includes measuring at least one parameter of the sewer line including average wastewater volume, flow rate, and retention time and administering a blended composition which includes an immediate release compound and an extended release compound into the sewer line to control concentration of an odorous compound therein. A method of facilitating sustained odor control in an extended sewer line is also disclosed. The method includes providing the blended composition including the immediate release compound and the extended release compound and instructing a user to administer the blended composition to the sewer line control concentration of the odorous compound therein. A system for providing sustained odor control in the extended sewer line including sensors to measure sewer line parameters and a controller to instruct administration of the blended composition is also disclosed.