A method for treating a urea aqueous solution includes a first stripping step of steam stripping an aqueous solution containing urea, ammonia and carbon dioxide at 0.2 to 0.6 MPaA in a first stripper to separate ammonia and carbon dioxide from this aqueous solution into a gas phase; a hydrolysis step of hydrolyzing urea in the solution obtained from the first stripping step at an LHSV of 10 to 20 h.sup.−1, at 1.1 to 3.1 MPaA and 180 to 230° C. in a catalytic hydrolyzer; and a second stripping step of steam stripping a liquid obtained in the hydrolysis step in a second stripper to separate ammonia and carbon dioxide from this liquid into a gas phase. The residual urea concentration can be reduced to 1 ppm or lower; the residual ammonia concentration can be decreased; LHSV can be increased; and an increase in apparatus size is minimized.

The present invention relates to a method of controlling a fresh-water production apparatus for treating a raw water in stages by N-stage (N is a natural number of 2 or larger) water treatment methods, the method including: a filtration-characteristic prediction step; a filtration-characteristic deviation assessment step; a filtration-characteristic deviation assessment step; a cyclic prediction calculation step; a control condition recording step; a cyclic prediction calculation step; and a control condition recording step, in which the fresh-water production apparatus is controlled on the basis of the control condition recording step for the (n−1)-th stage water treatment method and the control condition recording step for the n-th stage water treatment method.

A method and system for treating cyanide-containing fluids, in particular cyanide-containing waste water, wherein cyanide-containing fluid is subject to a pretreatment in a pretreatment zone, in which at least one predetermined pH value and a predetermined temperature is set, wherein a base fluid is formed with the pretreatment. Base fluid is reacted at least with an oxidation means in at least one reaction reactor, whereby an oxidation reaction of the cyanide is initiated. Fluid from the reaction reactor is transferred as intermediate fluid into at least one process reactor, in which conditions exist in which the oxidation reaction of the cyanide initiated in the reaction reactor can take place, wherein a process fluid is formed. A continuous flow of fluid is maintained at least periodically, wherein the base fluid is transferred continuously from the pretreatment zone into the reaction reactor, intermediate fluid is transferred continuously from the reaction reactor into the process reactor, and process fluid is removed continuously from the process reactor.

Described herein are methods and apparatus for solid-liquid separation with high efficiency, especially in treating spent filter backwash and sedimentation tank sludge produced in the water treatment process. It combines and applies gravity, electromagnetic force, dynamic filtration, and gravity condensation, magnetic and gravitational compression in one integrated device that produces high quality effluent water (less than 10 ppm suspended solid) and highly condensed sludge (less than 94-96% water content).

The present technology relates to present technology relates to materials, methods, processes and systems for clean water production—in particular, to unique hydrogels that can purify and decontaminate water, providing an effective and sustainable way to turn contaminated water into potable water. The present technology also contemplates methods of making such gels, methods of purifying water and providing purified water from contaminated water, and contemplates systems for accomplishing water purification in a rapid, cost-effective and environmentally sustainable way.

A disclosed subsea sediment separation and filtration system includes first and second separation devices, a spreader apparatus, and a storage device. The first separation device receives a water/sediment/oil mixture and from a subsea surface and separates the mixture into a first component containing cleaned sediment and a second component containing a water/oil mixture. The spreader apparatus disperses the cleaned sediment of the first component into a subsea environment of the spreader apparatus. The second separation device receives the second component from the first separation device and separates the second component into a cleaned water component and an oil component. The second separation device disperses the cleaned water component into a subsea environment of the second separation device and provides the oil component to the storage device. The first separation device may include a plurality of hydrocyclone devices, and the second separation device may include a high pressure hydrocyclone device.

A fluid treatment system for treating a fluid, the system including structure for moving a fluid therethrough the system, the structure for moving the fluid including a first inlet and a first outlet, further a primary fluid filter having a primary fluid filter inlet and a primary fluid filter outlet, wherein the primary fluid filter inlet is in fluid communication with the first outlet. Included with the system is a primary ultraviolet light module having a primary ultraviolet light module inlet and a primary ultraviolet light module outlet, wherein the primary ultraviolet light module inlet is in fluid communication with the primary fluid filter outlet and a secondary fluid filter having a secondary fluid filter inlet and a secondary fluid filter outlet, wherein the secondary fluid filter inlet is in fluid communication with the primary ultraviolet light module outlet, wherein the secondary fluid filter outlet discharges a first treated fluid.

A system for generating electricity, heat, and desalinated water having a gas turbine system connected to a first electric generator, a waste heat recovery boiler (WHRB) system, a combined heat and power (CHP) generation system connected to a second electric generator, one or more solar powered energy systems, and a desalination system. The desalination system is connected to the CHP generation system and the WHRB system. The gas turbine system generates electricity and heat, the WHRB system is connected to and uses the exhaust of the gas turbine system to provide heat and steam power to the CHP generation system. The CHP generation system produces and provides electricity and heat to the desalination system, which produces product water, and at least one solar powered energy system provides thermal energy to one or more of the gas turbine system, the WHRB system, the CHP generation system, and the desalination system.

Wastewater containing scale components, organic substances, inorganic ions, and the like, such as human effluent, generated in a closed system space, such as a nuclear shelter, a hazardous shelter, a space station or a moon-Mars mission manned spacecraft, or a lunar base is efficiently treated by a simple structural apparatus, so that water is recovered. After a hardness component is removed from water to be treated, such as human effluent, by a softening device, and heat exchange is performed between softening treated water and electrolysis treated water by a heat exchanger, by a high-temperature and high-pressure electrolysis device, organic substances, urea, ammonia, and the like are removed by electrolysis performed under high-temperature and high-pressure conditions. After the electrolysis treated water is processed by a deaeration treatment using a deaeration membrane device, a desalting treatment is performed by acid/alkali manufacturing electrodialysis devices and provided in series at two stages.

A biological reactor system treats concentrated contaminated water with a combination of upflow and downflow bioreactors that are downstream from a reverse osmosis or other concentrator. The system may have a fail safe configuration where flush water may be introduced to the reactors in the event of a power failure or when taking the reactors offline. Many reverse osmosis systems introduce antiscalant treatments upstream so that the reverse osmosis filters do not scale. However, such treatments result in superconcentrated conditions of the antiscalants in the contaminated water processed by the bioreactors. A flushing system may deconcentrate the bioreactors to prevent the antiscalants from precipitating and fouling the bioreactors.