A desalination system (100) having an intake unit (110) providing seawater to a pre-treatment unit (120) connected to a reverse osmosis (RO) desalination unit (130) and a post treatment unit (150). The desalination system (100) is configured to operate without any external addition of chemicals to simplify logistics and regulation concerns. The units of the system are configured to prevent biofouling, scaling and corrosion by mechanical and biological means including high flow speeds, biological flocculation of colloids, and making the water entering the RO units inhospitable to bacteria and other organisms that cause biofouling, hence preventing their settlement and removing them with the brine. Recovery rate is lowered and energy is recovered to increase the energetic efficiency and minerals that are added to the product water are taken from the brine.

A water filtration systems may comprise an under the sink RO water filtration system that is plumed into a building's water supply. For example, the water filtration systems may include an RO device at least partially installed underneath a sink, with the tap water connection plumbed directly to the sink cold water supply line, and a waste water drain line connected directly to the sink drain, such as the p-trap.

The invention relates to a ternary sewage treatment method integrating microbial fuel cells with anaerobic acidification and forward osmosis membrane, and belongs to the technical field of sewage treatment. The method of the invention comprises the following steps:

Sewage is driven into the anaerobic acidification device for mixture with the NaOH solution. The mixed liquid enters into the MFC for converting the enriched organics to bioelectricity and then flows back to the anaerobic acidification device. A part of the mixed liquid passes through the MF membrane module to form effluent and enters into the sedimentation basin for phosphate removal and finally passes through activated carbon adsorption column, another part passes through the FO membrane module to form effluent and obtain high quality recycled water after the RO membrane processing. The method is a new coupled model of FO membrane and MFC and it provide a ternary combined technique integrating MFCs with anaerobic acidification and FO membrane. The change and accumulation of sewage to organic acids are achieved under anaerobic acid production and FO retention, the electricity generation performance of MFC is improved, and the reuse of reclaimed water is realized by separating of FO and RO membranes. Finally, the wastewater reuse and electricity generation are realized synchronously.

Methods, systems, and techniques for removing ammonium from ammonia-containing water involve using a stack that has alternating product chambers and concentrate chambers for receiving ammonia-containing water and an acidic solution, respectively, with the chambers being bounded by alternating cation exchange membranes and proton permselective cation exchange membranes. Ammonium moves from the product chambers to the concentrate chambers across the CEMs and protons move from the concentrate chambers to the product chambers across the pCEMs when the stack is in use. An electrolyzer may also be used to convert the ammonium in the concentrate chambers into nitrogen.

A device and process are disclosed 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.

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 present invention provides a water treatment device comprising: a filtering unit for filtering raw water; a storing unit comprising a first chamber for storing purified water, which has passed through at least a predetermined number of filters provided in the filtering unit and thus has been filtered, and a second chamber, the volume of which changes according to the volume change of the first chamber; an extraction unit installed to provide the user with the purified water that has been filtered; an sterilizing water supply unit for supplying sterilizing water in order to sterilize/disinfect the storing unit; and a control unit for controlling the driving of the sterilizing water supply unit and the opening/closing of a channel for supplying the sterilizing water.

A method is provided for sanitizing a reverse osmosis system to supply high-purity permeate. Included in the method is supplying raw water to a feed tank and to a filter module using a raw-water inlet line having an inlet valve. A primary circuit is provided, and has a first pump connected to the filter module. A secondary circuit is provided, and has a second pump and a heater, both of which are connected to the filter module. The primary circuit is separated from the secondary circuit using a semipermeable membrane disposed in the filter module. The secondary circuit of the reverse osmosis system is cleaned or disinfected while the raw-water inlet line is in a disconnected state and the inlet valve is in a closed state using the second pump and the heater.

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.