In an apparatus for treating wastewater, water is screened, biologically treated and coagulated with the addition of chemicals before it is drawn through a membrane filter to produce permeate that is then passed through an electro-chemical cell to coagulate and/or oxidize residual contaminants such as phosphorous, nitrogen, or ammonia, and is then passed through a secondary membrane filter to capture and remove any remaining contaminants.

A dissolved air floatation apparatus including an ultrafine bubble-containing liquid production device and a dissolved air floatation tank. The ultrafine bubble-containing liquid production device includes a gas-liquid mixing unit and a bubble-containing liquid separation device. The bubble-containing liquid separation device swirls a liquid containing ultrafine bubbles and larger bubbles in a storage tank to concentrate the liquid that contains the ultrafine bubbles and the liquid that contains the larger bubbles to a central part of the swirling flow followed by discharge. A pressurized ultrafine bubble-containing liquid is mixed in a raw liquid containing a subject to be cleansed and is poured into the dissolved air floatation tank to cause a suspended substance and a dissolved component in the raw liquid to be adsorbed on an interface of fine bubbles and be floated in the dissolved air floatation tank to be extracted.

An integrated device and method for treating toxic and refractory wastewater are provided. The integrated device includes an adjusting pool, a first-stage reactor, a second-stage reactor, a third-stage reactor, a coagulation sedimentation pool, and a biochemical reaction pool that are sequentially connected in series, and further includes an aeration blower. Each of the first-stage reactor and the third-stage reactor is an advanced oxidation reactor, and the second-stage reactor is a Fenton reactor. The coagulation sedimentation pool includes 2 to 4 stages, and each stage of the coagulation sedimentation pool includes a coagulation tank, a primary sedimentation tank, and a secondary sedimentation tank that are connected in series. The biochemical reaction pool includes an anoxic tank, an aerobic tank, a settling tank, and a clean water tank that are connected in series. The wastewater treatment method combines the integrated device for treating toxic and refractory wastewater with reasonable process parameters.

A water treatment system includes a coagulating and flocculating system, an ultrafiltration membrane, and a fluid driver. The coagulating and flocculating system includes a first inlet for receiving water and a second inlet configured to receive a coagulating and flocculating agent. The coagulating and flocculating system is configured to precipitate dissolved phosphorous from the water, and to provide a flocculated effluent at an outlet of the coagulating and flocculating system. The ultrafiltration membrane includes an inlet that is fluidly coupled to an outlet of the coagulating and flocculating system. The ultrafiltration membrane is configured to separate the precipitated phosphorus from the flocculated effluent. The fluid driver is adapted to transfer the flocculated effluent from the outlet of the coagulating and flocculating system to the inlet of the ultrafiltration membrane at sustained flux rates of at least 150 LMH.

A method for treating wastewater involves electrolyzing a stream of seawater and wastewater mix within one or more electrolytic cells mounted outside a batch tank. The electrolyzed stream is piped to a quelling chamber which is mounted above the batch tank. A diluted polymer solution is injected at upstream of an in-line mixer piping into the quelling chamber substantially concurrently with the electrolyzed stream. The polymer solution and the electrolyzed stream are dispersed as a fine shower over residual seawater and wastewater in the batch tank. The polymer solution facilitates flocculation of the suspended solid particles and creates a distinct buoyant layer of flocculated solid particles attached with micro bubbles. A substantially clarified effluent is separated from the flocculated layer and neutralized prior to discharge. The flocculated layer is pumped from the batch tank to a dewatering system where entrained solids are compacted to a desired level. A centrate generated during the solids/sludge dewatering step is recirculated to the batch tank prior to addition of seawater during a subsequent treatment cycle as a supplement to the seawater.

This sampling device for a coagulation treatment device (1) comprises at least: a sealed-type coagulation reaction tank to which is introduced water to be treated to which a flocculant has been added; and a solid-liquid separation tank to which is introduced the water to be treated that has been drawn from the coagulation reaction tank, the sampling device comprising a sampling tank, a coagulation sensor installed inside the sampling tank, and a water sending pipe (43) which sends, from the coagulation reaction tank of the coagulation treatment device to the sampling tank, a part of the water to be treated inside the coagulation reaction tank.

An arrangement and a method for controlling a dewatering process including measuring values representing operating parameters of the gravitational sedimentation device and using the values as input values for a predictive multivariable model for predicting an operating state of the gravitational sedimentation device. The disclosure further relates to obtaining reference values for the operating parameters, determining at least one predicted output for an operating parameter of the gravitational sedimentation device, and comparing the predicted output to at the reference values to determine control values that will affect changes in operation of the gravitational sedimentation device.

As pellets grow from seed/sand in a fluidized bed pellent reactor, the weight of the reactor is measured and the density of the contents of the reactor is calculated, and the input flow of untreated water, water treatement chemical, and seed/sand are adjusted to provide improved removal of water hardness while reducing fine particulates in the outflow of softened water from the reactor.

Decontamination of water using low-cost technology for municipal wastewater treatment for safe irrigation reuse is provided. More specifically, wastewater is decontaminated by coagulation/flocculation followed by biological filtration while incorporating, in several stages, wastes from other industries such as ceramic kiln dust and biochar. Ceramic kiln dust and alum are used in a coagulation/flocculation process which is then followed by biofiltration using a biochar material.

Methods and systems for removal of ions from aqueous fluids are provided. In certain embodiments, the present disclosure provides a method of removing one or more oxyanions from an aqueous fluid, including the steps of contacting an aqueous fluid containing oxyanions with an aluminum metal whereby aluminum ions are released from the aluminum metal into the aqueous fluid, wherein the one or more oxyanions in the aqueous fluid react with the aluminum ions to form one or more ettringites; controlling a rate of release of the aluminum ions from the aluminum metal; and removing at least a portion of precipitated ettringites from the aqueous fluid.