Movable thick dehydration device and method for eluent sediment from medium- and low-concentration ammonia nitrogen are provided. The device integrates the existing eluent preparing mechanism, a transferring mechanism, pumping mechanisms, a transport vehicle, an automatic controlling system, an eluent collecting pool, primary and secondary sedimentation pools, and primary and secondary processing units. After post-treatment and recovery of eluent waste from rare earth mines, ammonia nitrogen and rare earth heavy metals in the eluent of rare earth mines can be recovered and disposed, and 90% of ammonia nitrogen and over 95% of rare earth in the eluent can be recycled. The device is movable and automated, and therefore suitable for environmental treatment of closed rare earth mines with residual ammonia nitrogen. Meanwhile, it is beneficial to reduce investment costs of capital construction, disposal site restoration of environmental treatment of rare earth mines with residual ammonia nitrogen.

Saltwater to freshwater conversion cells are provided. The saltwater to freshwater conversion cell includes a positive electrode; a negative electrode disposed opposite and parallel to the positive electrode; a first plastic perforated plate positioned adjacent to the positive electrode and between the positive electrode and the negative electrode; a second plastic perforated plate positioned adjacent to the negative electrode and between the positive electrode and the negative electrode; a power supply configured to generate an electric field between the positive electrode and the negative electrode; and a saltwater stream comprising a plurality of positively charged sodium ions and a plurality of negatively charged chloride ions, the saltwater stream flowing through the conversion cell. The positive electrode and the first plastic perforated plate define a chloride-dense water channel, the negative electrode and the second plastic perforated plate define a sodium-dense water channel, and the first plastic perforated plate and the second plastic perforated plate define a desalinated water channel. The electric field is configured to cause the plurality of negatively charged chloride ions in the saltwater stream to move through the first plastic perforated plate and into the chloride-dense water channel and the plurality of positively charged sodium ions in the saltwater stream to move through the second plastic perforated plate and into the sodium-dense water channel.

Liquid solution concentration systems, and related methods, are generally described. In some embodiments, the system is an osmotic system comprising a plurality of osmotic modules. For example, the osmotic system can comprise a feed osmotic module configured to produce an osmotic module retentate outlet stream having a higher concentration of solute than the retentate inlet stream transported to the feed osmotic module. The osmotic system can also comprise an isolation osmotic module fluidically connected to the feed osmotic module. The osmotic system can also optionally comprise a purification osmotic module fluidically connected to the feed osmotic module and/or the isolation osmotic module. Certain embodiments are related to altering the degree to which the feed osmotic module retentate outlet stream is recycled back to the retentate-side inlet of the feed osmotic module during operation. Additional embodiments are related to the manner in which the retentate-side effluent from the isolation osmotic module is distributed among the system modules during operation.

Water deionization systems based on electrochemical water desalination or softening using a capacitive or intercalative deionization devices including a stack of electrochemical cells. Each cell includes first and second electrodes and an ion exchange membrane. Each cell includes inlet and outlet channels with control valves that control the separation of the source water into brine (e.g., concentration) and clean water (e.g., purification) streams. The deionization device or module may include multiple electrochemical cells connected electrically in series, parallel or a combination of both. The cells may also be in serial, parallel, or combined fluid communication. The output water of one or more streams from each cell or collection of cells may be recirculated and combined with one or more input water streams to improve the electrochemical energy efficiency of the cells. The electrochemical cells at different rows may have varying electrode thickness, area and loading of the active material.

The high water recovery hybrid membrane system for desalination and brine concentration combines nanofiltration, reverse osmosis and forward osmosis to produce pure water from seawater. The reject side of a nanofiltration unit receives a stream of seawater and outputs a brine stream. A permeate side of the nanofiltration unit outputs a permeate stream. A feed side of a reverse osmosis desalination unit receives a first portion of the permeate stream and outputs a reject stream. A permeate side of the reverse osmosis desalination unit outputs pure water. A draw side of at least one forward osmosis desalination unit receives the reject stream and outputs concentrated saline solution. A feed side of the at least one forward osmosis desalination unit receives a second portion of the permeate stream and outputs a dilute saline stream, which mixes with the first portion of the permeate stream fed to the reverse osmosis desalination unit.

Provided are electrodialysis systems comprising a plurality of electrodialysis devices, wherein each electrodialysis device of the plurality of electrodialysis devices has a product inlet stream, a product outlet stream, a brine inlet stream, and a brine outlet stream. The product inlet stream for a first electrodialysis device comprises the brine outlet stream of a second electrodialysis device. Further, a first portion of a feed stream is the brine inlet stream for the first electrodialysis device and a second portion of the feed stream is the brine inlet stream for the second electrodialysis device or a third electrodialysis device.

Fluid treatment systems and components are provided for a removal of solid matter from water or other fluids in which a chemical or chemicals may be introduced into the fluid under pressure to coagulate and/or conglomerate the solid materials and cause them to be dropped out of the treatment system and be removed. The fluid treatment system can include: an equalization chamber receiving a wastewater; a clarification chamber receiving a partially separated water from the equalization chamber; a mixing tube having an inlet end and an outlet end; and a sludge detector.

A pretreatment method is provided for efficiently recovering a solvent from a raw material mixture comprising water, the solvent and a polymer dissolved and/or dispersed therein.

The pretreatment method includes a step of subjecting the raw material mixture 12 to an ultrafiltration treatment 16, 18 to filter out the polymer so as to obtain a filtrate 36 of which polymer content is reduced.

Disclosed herein is a sludge drying system comprising: a system input for receiving a wet sludge stream, wherein the wet sludge stream comprises water and solid material; a first dryer arranged to receive, at an input of the first dryer, the wet sludge stream and to heat the wet sludge stream such that at least part of the water in the wet sludge stream is evaporated to thereby generate evaporate and a partially dry sludge stream, wherein the first dryer is an indirectly heated rotating disc dryer that comprises a first output for outputting evaporate and a second output for outputting the partially dry sludge stream; a second dryer that is an indirectly heated rotating disc dryer and is arranged to receive, at a first input of the second dryer, a stream that is dependent on the partially dry sludge stream output from the first dryer and to receive, at a second input of the second dryer, the evaporate from the first dryer, wherein the second dryer is arranged to use to the received evaporate to indirectly heat the received stream at the first input to thereby generate and output a substantially dry sludge stream; and a system output for outputting at least part of the substantially dry sludge stream from the system.

Introduced here are treatment systems and associated processes for treating water using magnetic fields. A treatment system can comprise a hydromagnetic resonator that creates the magnetic fields through which water can be directed. A hydromagnetic resonator can include at least one expansion chamber that provides a tortuous path along which water is able to flow through a magnetic field created by an arrangement of permanent magnets and at least one convergent-divergent nozzle designed to accelerate the flow of waterpassing through a throat segment. Water directed through a hydromagnetic resonator will be magnetically treated while flowing through the magnetic field created by the arrangement of permanent magnets within each expansion chamber and then pressurized while flowing through the throat segment of each convergent-divergent nozzle.