The invention relates to a method and an arrangement for wastewater treatment, in which at least portions of the sewage sludge contained in the wastewater (0) are subjected to a hydrolysis (8). The hydrolysis (8) is carried out as a thermal hydrolysis. After the hydrolysis step (8), a drying process is (19) carried out. The drying process (19) is a process operating with positive pressure in the steam region. At least parts of the steam resulting from the drying process (19), which operates with positive pressure, are fed (20) to the portions of the sewage sludge in the thermal hydrolysis (8).

The invention relates to a method for nitrogen removal from aqueous medium, comprising steps of (a) converting NH.sub.4.sup.+ in the aqueous medium to NO.sub.2.sup.− by partial aerobic nitrification, (b) partially reducing the obtained NO.sub.2.sup.− to N.sub.2O in anoxic conditions, and (c) decomposing N.sub.2O to N.sub.2 with energy recovery. A mixture of ferrous sulfate and ferric sulfate is used in step (b) for reduction of NO.sub.2.sup.− to N.sub.2O.

System (100) and method for processing biomass. The system comprises a combined heat and power plant (102), an interface (114) for feeding biogas to a traffic fuel production unit, interfaces (114) to a district heating system (106a) and an electrical grid (106b), and a hydrolysis device (108), a digestion device (110), a dryer (116) and a heat recovery unit (112), which are operatively coupled for transferring heat, intermediate products and final products of the process, wherein raw biomass is received into the Fuel hydrolysis device (108), biomass processed by the hydrolysis device (108) is fed to the digestion device (110), biogas obtained in the digestion device (110) is fed to the traffic fuel production unit (104), heat is recovered from the hydrolysis device (108), biomass processed by the digestion device (110) is dried by the heat recovered from the hydrolysis device (108), heat is recovered from the dryer (116), heat recovered from the dryer (116) is fed to the hydrolysis device (108) to be used in pre-heating of the received raw biomass, heat recovered from the dryer (116) is fed to the district heating (106a), and production of electricity is fueled by the dried biomass from the dryer (116).

Systems and methods for the desalination of water are disclosed. A system includes a concentrated solar power (CSP) system, the CSP system operable to concentrate solar energy to increase temperature and pressure of a heat transfer fluid and operable to produce steam utilizing heat from the heat transfer fluid; a photovoltaic (PV) system, the PV system operable to collect solar energy to produce electricity; a desalination system in fluid communication with the CSP system and in electrical communication with the PV system, the desalination system operable to produce desalinated water from a salt water source utilizing the steam from the CSP system and electricity from the PV system; and a pump station in fluid communication with the CSP system and the desalination system, and in electrical communication with the PV system, the pump station operable to transmit the desalinated water to consumers for use.

Separation systems are described that may include forward osmosis (FO) membranes for offshore desalination and sulfate removal. The system may use submerged FO elements (e.g. operating underwater in the ocean). The system may use FO elements in combination with high-pressure reverse osmosis (RO) elements and processes. The system may use FO elements in combination with membrane distillation elements and processes. The system may create a suction and pressurized flow from a submerged FO membrane process to a reverse osmosis system on a platform, ship, or other offshore or “along shore” structure. The product water may be used for enhanced oil recovery (EOR).

A wastewater treatment system includes a circulating fluidized bed evaporator defining a longitudinal axis vertical with respect to gravity. The evaporator has a wastewater inlet to provide wastewater to the circulating fluidized bed evaporator. A heat inlet is axially below the wastewater inlet to provide heat to the circulating fluidized bed evaporator for evaporating the wastewater. An outlet is axially above the wastewater inlet and the heat inlet.

Disclosed is a method for improving biological production of hydrogen from protein-containing wastewater comprising two stages: ultraviolet radiation pretreatment of protein-containing wastewater and biological production of hydrogen under a neutral pH condition and intermediate temperature condition.

An ocean wave-driven sea water desalination plant employs ocean bottom mounted and hinged flaps driven in oscillating motion by wave surge force to drive rotary pumps which directly pressurize filtered sea water for use by a reverse osmosis (RO) plant and a hydraulic motor-generator set which provides electrical power to RO plant peripheral devices. Means are provided to control the filtered sea water pressure presented to the RO membranes to a preferred set point value. Means are also provided to control the pump reaction torque presented to the flap independently of water pressure by adjusting the effective pump displacement with a pulse width modulated valve shunting the pump ports to maximize captured wave power. Control of pump reaction torque may be effected slowly according to average sea state conditions or in real-time to further enhance captured wave power.

Provided is a reverse osmosis treatment apparatus which decreases operation power by utilizing a back pressure caused by regulating an amount of permeated water. The reverse osmosis treatment apparatus includes a first pressure vessel for a primary treatment of untreated water, and a second pressure vessel for a secondary treatment of the water treated by the primary treatment, wherein a reverse osmosis membrane element having a reverse osmosis membrane or the plurality of reverse osmosis membrane elements are arranged in series along a water collection pipe in the first pressure vessel and the second pressure vessel. The first pressure vessel includes a first outlet pipe which discharges permeated water, and a permeated water flow control valve connected to the first outlet pipe and regulating a pressure in the first pressure vessel. An energy recovery apparatus is provided between the first outlet pipe and the permeated water flow control valve.

An apparatus, system and method to purify water is disclosed. Pumps and energy recovery devices for taking water from an intake, filtering the water to remove solid contaminates before running the filtered water through the reverse osmosis system to the discharge device and purified water lines are described. The system may comprise a control panel that controls the plurality of filters, plurality of reverse osmosis membranes, purified water line and effluent discharge device, to achieve favorable water purification. A method that utilizes the apparatus and/or system is described herein.