Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

A fluid purification system has cells whose purifying capability can be regenerated. Some of the cells are arranged in series to reach a high level of purification. An automatic valve network is controlled to cycle the cells in a way that levels the loads on each, thereby maximizing the service interval for replacing expired cells, enabling all of the cells to be replaced at the same time after having each contributing approximately equally to the purification load, and operated such that at any one time, at least one cell is regenerated so as to enable continuous up-time.

A device (10) for capacitive deionization of an aqueous media containing dissolved ion species, said device comprising a cell with a first primary electrode (2) and a second primary electrode (3) arranged opposite the first primary electrode (2) and preferably separated by at least one non-conductive spacer (4, 4). A third electrode (7) is arranged between the first and the second electrode. The third electrode (7) is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode.

A device and process for the separate removal of oppositely charged ions from electrolyte solutions and recombining them to form new chemical compositions. The invention provides the ability to create multiple ion flow channels and then form new chemical compositions therefrom. The process is accomplished by selectively combining oppositely charged ions of choice from different electrolyte solutions via the capacitive behavior of high electrical capacitance electrodes confined in insulated containers. Industrial plants employing the inventive process can have the flexibility to produce needed industrial chemical compounds such as Soda Ash, Caustic Soda, hydrochloric acid and chlorine gas, based on market demand, and can be located near points of consumption to significantly reduce transportation costs.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

The concentrated and dilute saline water distribution systems of Electro Dialysis Reversal EDR or Capacitive Electro Dialysis Reversal CEDR are modified by feeding and retrieving the saline water to and from multiple spacers in an electrodialysis stack such that (1) the saline water enters and leaves the spacers in the plane of the thin spacers rather than traditionally perpendicular to them and (2) the saline waters are independently fed and retrieved to and from the spacers through long and small cross-sectional area tubes such that the electrical resistance to ion flow is very high relative to the electrical resistance to ion flow through the electrodialysis stack containing the cation and anion exchange membranes and dilute and concentrated saline water spacers. Consequently, little ion flow will occur in the saline water distribution systems and consequently most of the ions flow through the electrodialysis stack of EDR or CEDR providing effective desalination regardless of the salinity levels of the feed waters.

A fluid purification system has cells whose purifying capability can be regenerated. Some of the cells are arranged in series to reach a high level of purification. An automatic valve network is controlled to cycle the cells in a way that levels the loads on each, thereby maximizing the service interval for replacing expired cells, enabling all of the cells to be replaced at the same time after having each contributing approximately equally to the purification load, and operated such that at any one time, at least one cell is regenerated so as to enable continuous up-time.

A fluid purification system has cells whose purifying capability can be regenerated. Some of the cells are arranged in series to reach a high level of purification. An automatic valve network is controlled to cycle the cells in a way that levels the loads on each, thereby maximizing the service interval for replacing expired cells, enabling all of the cells to be replaced at the same time after having each contributing approximately equally to the purification load, and operated such that at any one time, at least one cell is regenerated so as to enable continuous up-time.

This Capacitive Electro Dialysis Reversal (CEDR) invention desalinates and concentrates saline water. The CEDR unit employs two identical parallel oppositely oriented modified Electro Dialysis Reversal EDR constructions that have shared dilute and concentrated saline water channels. The four electrodes of the two identical oppositely oriented parallel EDR like constructions are replaced with four supercapacitor electrodes. Each EDR like construction consists of a stack of ion exchange membranes and spacers plus the supercapacitor electrodes but one cation exchange membrane is trimmed from each of the two stacks of EDR like ion exchange membranes. During a cycle of operation, the supercapacitor electrodes discharge and then charge causing ions to be pulled out of the shared dilute saline water channels and placed in the shared concentrated saline water channels except at the ends where the ions flow in and out of the supercapacitor electrodes. The two adjacent supercapacitor electrodes on either end are exchanged between the two-modified parallel EDR like constructions at the end of each cycle of operation. This process of supercapacitor discharging and charging and then exchanging places operates continuously. A benefit of this CEDR invention is that no gasses are formed at the supercapacitor electrodes like EDR does using conducting electrodes but a similar performance to that of EDR is maintained. A feature of this CEDR invention is that almost all the energy delivered to it is used in desalination and saline water concentration while energy losses at the supercapacitor electrodes located at the ends of the CEDR unit are very small and negligible.