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.

The present application provides a waste water preconditioning system for limiting mercury concentrations in a waste water stream resulting from treatment of a flue gas. The waste water preconditioning system may include a wet flue gas desulfurization system for treating the flue gas with an aqueous alkaline slurry, a sulfite detector to determine the concentration of sulfite in the aqueous alkaline slurry, and to produce the waste water stream with a mercury concentration of less than about five micrograms per liter. The waste water preconditioning system also may include a waste water treatment system downstream of the wet flue gas desulfurization system.

The invention comprises an activated sludge treatment system and process that aerates wastewater undergoing treatment using venturis.

Systems for removing debris from a water reservoir include a moveable floating skimmer device positioned within the water reservoir and configured to receive floating debris, the skimmer device comprising an adjustable weir for capturing the debris and a receptacle for containing the debris; a discharge pipe connected to the skimmer device, the discharge pipe configured to receive the debris and a first portion of water from the receptacle in the skimmer device; a debris separator fluidly connected to the discharge pipe and configured to receive the debris and the first portion of water from the discharge pipe, the debris separator further configured to separate the debris from the first portion of water; a pump positioned between the discharge pipe and the debris separator and configured to transport the debris and the first portion of water in the discharge pipe to the debris separator via a pump outlet; and a recycle line connected to the debris separator and configured to return a second portion of water that exits the debris separator back to the water reservoir.

Anaerobic wastewater treatment systems, devices and methods complete three-phase separation of biogas, liquids and solids (e.g., biomass) using overlapped gas hoods or baffles and one or more conically-shaped settlers having a varying cross-sectional area.

A dewatering system for separating a slurry into solid material and effluent water. The dewatering system comprises a plurality of support frames arranged to enclose an interior space of the dewatering system, with the interior space being configured to receive the slurry. The dewatering system further includes geo-fabric material positioned on a portion of the support frames, with the geo-fabric material being configured to filter the slurry received within the interior space, such that effluent water permeates through the geo-fabric material and is discharged from the interior space. The dewatering system further comprises a dump door assembly associated with at least one of the support frames, with the dump door assembly including a plurality of hatches configured to selectively open to allow effluent water to be discharged from the interior space of the dewatering system.

A filter system for filtering a fluid stream is disclosed herein. The filter system includes a first fluid passage, a first chamber, a second chamber, an adsorbing media, and a second fluid passage. The first fluid passage is arranged such that a fluid stream can flow through the first fluid passage and into the filter system. The first chamber is arranged to hold suspended or dissolved solids, pollutants, and nutrients that are filtered from the fluid stream. The second chamber is positioned above the first chamber and in fluid communication with the first chamber. The adsorbing media is positioned in the second chamber. The second fluid passage is arranged such that filtered fluid from the fluid stream can flow out of the filtering system through the second fluid passage.

A sewage treatment apparatus comprises an external box body internally being provided with an anaerobic zone, an aerobic zone, a settling zone, a sewage reduction zone and an apparatus zone separated from each other, wherein the anaerobic zone, the aerobic zone, the settling zone and the sewage reduction zone communicate in sequence, the anaerobic zone communicates with a septic tank, the aerobic zone communicates with the anaerobic zone to reflux a part of mixed liquid to the anaerobic zone, the settling zone communicates with the anaerobic zone to reflux a part of active sludge to the anaerobic zone, and the sludge reduction zone communicates with the anaerobic zone or the septic tank; and the apparatus zone is internally provided with a detection unit for detecting various parameters during a sewage treatment process and a controller for controlling working states according to a detection result of the detection unit.

Provided is a method for treating a hexavalent chromium-containing aqueous solution by water treatment employing a titanium dioxide photocatalyst that is excellent in both photocatalytic activity and solid-liquid separation performance. The method according to the present disclosure includes the steps of: adding catalyst particles to the aqueous solution; reducing hexavalent chromium by irradiating the aqueous solution with light having a wavelength of 200 nanometers or more and 400 nanometers or less while stirring the catalyst particles in the aqueous solution; and stopping the stirring and separating the catalyst particles from the aqueous solution by sedimentation. Each catalyst particle is composed only of a titanium dioxide particle and a zeolite particle, the titanium dioxide particle is adsorbed on the outer surface of the zeolite particle, the zeolite particle has a silica/alumina molar ratio of 10 or more, and the catalyst particles are contained in the aqueous solution at a concentration of 0.4 grams/liter or more and 16 grams/liter or less.

A method of treating process water of a flotation plant is disclosed. The flotation plant comprises a mineral flotation line and a process water circuit for treating underflow and/or overflow of the flotation line. The process water circuit comprises a gravitational solid-liquid separator for dewatering underflow and/or overflow of the mineral flotation line to separate sediment from supernatant comprising at least water and unrecovered fine particles comprising valuable material; and a recover water tank for collecting process water. According to the method, prior to leading supernatant from the gravitational solid-liquid separator into the recover water tank, it is subjected to cleaning flotation, in which at least 90% of the flotation gas bubbles have a size from 0.2 to 250 μm, in a cleaning flotation unit. An arrangement for treating process water of a flotation plant, and its use are also disclosed.