The present disclosure provides a packed rotating biological contactor and a method for ammonia nitrogen conversion based on the packed rotating biological contactor. The packing frame of the packed rotating biological contactor provided in the present disclosure is formed by engaging two meshed disks, the hollow structure thus formed can be filled with packings, increasing the tilling amount of the packings; the selection of packing types can improve the film-forming rate of microorganism and shows a good adsoiption effect on the microorganism, so that the biofilm formed on the surface of packings can resist the impact of water flow and avoid shedding. The selection of disk meshes and packing types also increases the specific surthce area of the packed rotating biological contactor, which can improve the acclimation efficiency of microorganisms and enable the packed rotating biological contactor to carry more microorganisms, thus forming biofilms with excellent performance.

An ocean alkalinity enhancement (OAE) system that reduces atmospheric CO.sub.2 and mitigates ocean acidification by electrochemically processing feedstock solution (e.g., seawater or brine) to generate an alkalinity product that is then supplied to the ocean. The OAE system includes a base-generating device and a control circuit disposed within a modular system housing deployed near a salt feedstock. The base-generating device (e.g., a bipolar electrodialysis (BPED) system) generates a base substance that is then tested and processed (e.g., mixed/diluted with processed feedstock solution, seawater or another saltwater solution and/or reacted with CO.sub.2) to generate the ocean alkalinity product. The control circuit controls the base-generating device such that the alkalinity product is supplied to the ocean only when supplying the alkalinity product will not endanger sea life. Modified BPED systems include features that facilitate autonomous system operations including enhanced maintenance cycle operations and a reduced reliance on external fresh water sources.

A method of controlling an output relay of a chemical controller is disclosed. The output relay is coupled to a pump configured to introduce at least one chemical into the aquatic application. The chemical controller controls the operation of the pump using the output relay. The method includes the step of utilizing a watchdog timer circuit to determine that a processor has failed to send a reset signal to the watchdog timer circuit before a timer of the watchdog timer circuit reaches zero. The method further includes the step of outputting a processor fault signal from the watchdog timer circuit.

An extraction manifold for extracting digestate from a covered lagoon digester includes a digester vessel being shaped generally as a rectangular prism lacking an upward facing face and having a floor sloping generally downward from an intake face to an extraction face of the digester vessel. The intake face and extraction face are oriented vertically, situated in opposed relation on a longer horizontal axis. Each effluent pipe terminates in an extraction nozzle on one end and an independently addressable actuatable valve on the opposite end. Each actuatable valve communicates with a manifold plenum such that actuation of the valve draws digestate from the floor in a region of the floor adjacent to the extraction face and in proximity to the extraction nozzle. A valve controller actuates valves to remove digestate from the region of the floor adjacent to the extraction face. The valve controller includes sensors to monitor biogas production.

Disclosed are methods and systems that facilitate more accurate measurement of the turbidity, i.e., insoluble ion content, of source water streams in water treatment processes, and in turn more accurate dosing of metal salt coagulants to cause these insoluble ions to floc and precipitate from the source water stream. Methods and systems for calibration of streaming current sensors used for such turbidity/insoluble ion content measurement are also disclosed.

A recirculating aquaculture system (RAS) is disclosed, which includes a main tank, in which fish or shellfish are farmed; a first reactor fluidically connected to the main tank, wherein the first reactor is a batch reactor that operates under anoxic conditions; a second reactor fluidically connected to the main tank, wherein the second reactor is a moving bed biofilm reactor (MBBR);a feed stream fluidically connected to the main tank; and a data-driven controller operably connected to the first reactor, the second reactor, and the feed stream, wherein the data-driven controller is configured to bring and maintain the system (RAS) at a desired state.

A capture device for capturing a target gas from a gas flow is disclosed that can be continuously used without requiring consumption of target gas binding salts. To this end, the device is arranged to generate separate acidic and alkaline streams of fluid by electrolyzing water, binding the target gas to the hydroxide ions in the alkaline fluid stream or the hydronium ions in the acidic stream, and recombining the generated streams to release the bound target gas and regenerating part of the electrolyzed water for further electrolysis. Such a capture device may for instance be used in a gas purification system, e.g. an air purification system for controlling target gas levels in a confined space such as a vehicle cabin, domestic dwelling or office space, a target gas generation system or a target gas enrichment system, e.g. for creating target gas-rich air for horticultural purposes. A method for capturing target gas from a gas flow and optionally utilizing the captured target gas is also disclosed.

A water monitoring device monitors and maintains swimming pool chemistry. The device includes sensors that detect water chemistry. The water monitoring device can communicate with computers and servers. This system can be used to determine if corrections to the water chemistry are required to maintain water sanitation. The device can monitor: pH, air temperature, water temperature, free chlorine levels, oxidation reduction potential, alkalinity, oxygen demand, water movement and velocity, and electrical conductivity.

Disclosed herein are methods and systems for removing carbon dioxide (CO.sub.2) from water and quantifying the carbon so removed, thus facilitating valuation of that carbon for schemes (e.g., Kyoto agreement) that attach financial rewards for capture, sequestration or removal of carbon or CO.sub.2.

There is set out highly efficient processes for the production of alkaline spring waters. The processes are designed to minimize the use of the additive alkaline formulations used to create the alkalinity in the spring waters and the use of a maximum amount of non-purified spring water in the formulation of the final alkaline spring water product. This is accomplished by dividing the input spring water into at least two portions. One portion undergoes a purification process and the other is not purified. Each portion is tested in increments for the amount of alkaline formulation needed to attain a pH of at least about 10 and designated potassium ion and sodium ion contents. From the testing the amount of the purified spring water and the amount of non-purified spring water needed to be combined to yield a pH of at least about 10 and the designated potassium ion and the sodium ion contents is calculated. It is desired to use a minimum of alkaline formulation to achieve the set Ph and potassium and sodium ion concentration. In this way the more costly components of the alkaline formulation and the purified spring water can be minimized, but yet the taste and stability maintained over a period of time. The processes apply to waters from a single spring and from a plurality of springs.