The methods and systems disclosed here relate to treating water. In certain embodiments, a treatment system comprises an electrochemical water treatment device, a recirculating concentrate stream in fluid communication with the electrochemical water treatment device, a flow control device in fluid communication with a first flow path comprising acidic water and configured to be in fluid communication with the recirculating concentrate stream, and a second flow path comprising feed water and configured to be in fluid communication with the recirculating concentrate stream, and a control system in communication with the flow control device. The treatment system may further comprise a recirculating dilution stream in fluid communication with a second inlet and a second outlet of the electrochemical water treatment device.

A method and system for operating a seal gas compressor utilized in a direct reduction process including: monitoring a pH level of a water stream used in the seal gas compressor, wherein the pH level of the water stream is affected by a reformer flue gas stream that comes into contact with the water stream, wherein the monitoring step is carried out one or more of upstream of the seal gas compressor and downstream of the compressor; and adjusting the pH level of the water stream to maintain the pH level of the water stream within a predetermined range based on feedback from the monitoring step. The method includes maintaining the pH level of the water stream upstream of the seal gas compressor in a range between 7.5 and 10 and maintaining the pH level of the water stream downstream of the seal gas compressor in a range between 7.8 and 9.5.

Disclosed herein are methods, systems, and devices for generating electricity from an effluent source. In the presence of electrogenic bacteria and substrate electrodes, an electroactive biofilm is produced which possesses bioconductive capacity for efficiently producing an electric current while treating an effluent source such as, e.g., wastewater. This disclosure relates generally to the production of electricity from a biological source. In particular, this disclosure relates to microbial fuel cells (MFCs) and other bioelectrochemical systems (BES) that exploit an exogenous fuel source.

A method including acidifying a solution including dissolved inorganic carbon; vacuum stripping a first amount of a carbon dioxide gas from the acidified solution; stripping a second amount of the carbon dioxide gas from the acidified solution; and collecting the first amount and the second amount of the carbon dioxide gas. A system including; a first desorption unit including a first input connected to a dissolved inorganic carbon solution source to and a second input coupled to a vacuum source; and a second desorption unit including a first input coupled to the solution output from the first desorption unit and a second input coupled to a sweep gas source.

Water treatment compositions are provided that are effective for mitigating corrosion or fouling of surfaces in contact with aqueous systems. The water treatment compositions can include one or more azole compounds, one or more transition metals, and one or more dispersants, in addition to various other additives. The water treatment compositions can exclude phosphorus and still be effective. Methods for mitigating corrosion or fouling of a surface in an aqueous system are also provided.

The disclosure provides automated methods and systems for optimized dosing of chemicals, such as coagulants, acids, and/or bases, in water treatment processes. The methods and systems of the disclosure can provide a coagulant dosing regimen that mitigates turbidity and organic contaminant content while maintaining effective floc precipitation, agglomeration, and settling without significant human intervention.

A method for treating a waste stream from a copper CMP process including dissolved copper and abrasive particles having a number weighted mean size of less than 0.75 μm includes introducing the waste stream into a feed tank, flowing the waste stream from the feed tank into an ultrafiltration module, filtering the waste stream through a membrane of the ultrafiltration module to form a solids-lean filtrate, directing the solids-lean filtrate from the ultrafiltration module through an ion exchange unit to remove dissolved copper and produce a treated aqueous solution having a lower copper concentration than the copper concentration of the waste stream, backwashing the membrane ultrafiltration module to remove the slurry solids from the membrane of the ultrafiltration module, and combining the removed slurry solids with the treated aqueous solution to form a combined discharge stream having a copper concentration suitable for discharge into the environment.

A method of increasing operational efficiency of a power plant includes determining an average rate of accumulation of scale-forming compounds in a cooling water source, directing water from the cooling water source having a first concentration of scale forming compounds through a treatment system to produce a treated water having a lower concentration of scale-forming components than the first concentration by operating the treatment system with operating parameters selected such that a rate of removal of the scale-forming components from the water in the treatment system is greater than the average rate of accumulation of the scale-forming components, directing the treated water back into the cooling water source, and circulating water including the treated water from the cooling water source through a cooling system of the power plant.

A biofilter irrigation system comprises a cylindrical vessel having a central axis, a media bed positioned within the vessel, a spray head system positioned above the media bed, the spray head system comprising a central hub positioned at the central axis of the vessel, at least one arm extending distally from the central hub toward a wall of the vessel and configured to rotate about the central axis, and a plurality of nozzles connected to the at least one arm. The biofilter irrigation system further comprises a fluid outlet positioned below the media bed.

A method and system for treating cyanide-containing fluids, in particular cyanide-containing waste water, wherein cyanide-containing fluid is subject to a pretreatment in a pretreatment zone, in which at least one predetermined pH value and a predetermined temperature is set, wherein a base fluid is formed with the pretreatment. Base fluid is reacted at least with an oxidation means in at least one reaction reactor, whereby an oxidation reaction of the cyanide is initiated. Fluid from the reaction reactor is transferred as intermediate fluid into at least one process reactor, in which conditions exist in which the oxidation reaction of the cyanide initiated in the reaction reactor can take place, wherein a process fluid is formed. A continuous flow of fluid is maintained at least periodically, wherein the base fluid is transferred continuously from the pretreatment zone into the reaction reactor, intermediate fluid is transferred continuously from the reaction reactor into the process reactor, and process fluid is removed continuously from the process reactor.