This method entails: collecting in advance untreated ballast water to which a chlorine-based active substance has not been added; measuring in advance the turbidity of the untreated ballast water; and adding a chlorine-based active substance with an adding amount determined on the basis of the turbidity. The amount of the chlorine-based active substance to be added is set according to the turbidity such that the concentration of total residual oxidants (TRO) is 0.5-3 mg/L (asCl.sub.2) when the ballast water is discharged.

A method for controlling water purification, and a water purification apparatus (1). The apparatus (1) comprises a reverse osmosis membrane (3a) configured to receive feed water from a feed pump (5), and to produce permeate water and reject water. The method comprises measuring (S1) a property indicative of an inlet water quality C.sub.inlet of inlet water to the feed pump (5), and determining (S2) a target recovery for the water purification based on the property indicative of the inlet water quality. The method further comprises controlling (S3) a feed pump speed to a predetermined speed, or to a speed determined based on a relation between the feed pump speed, the inlet water quality C.sub.inlet and a target permeate water quality C.sub.per, based on the inlet water quality. The method comprises measuring (S4) a property indicative of a product water flow rate Q.sub.prod, wherein the product water is permeate water that is delivered for consumption, recirculating (S5) a first portion of the reject water, and controlling (S6) a drain flow rate Q.sub.drain to drain, from a second portion of the reject water, to accomplish the target recovery based on the product water flow rate Q.sub.prod.

A system for providing treated water includes a water treatment unit including an inlet water quality probe, a worker bed, a probe to measure a parameter of water from the worker bed, a polisher bed connected downstream from the worker bed and having a probe to measure a parameter of water from the polisher bed, and a flow meter upstream of the worker bed or downstream of the polisher bed. A controller in communication with the flow meter and the probes is configured to receive data from same. A remote server in communication with the local water treatment unit is configured to receive data from the local water treatment unit. The controller or the server may determine a cumulative flow total, a billing cycle flow total, a current exchange flow total, a contaminant load, or a remaining capacity of the water treatment unit.

Water treatment systems are disclosed. The system includes an electrochemical cell having an inlet and an outlet, a cathode comprising a catalytic material for electrochemical generation of persulfate free radicals, and an anode, a source of a persulfate positioned upstream of the electrochemical cell, first contaminant concentration sensor positioned upstream of the electrochemical cell, and a controller operatively coupled to receive one or more input signals from at least the first contaminant concentration sensor. Methods of treating water using the electrochemical cell disclosed herein are disclosed. Methods of facilitating water treatment by providing the electrochemical cell disclosed herein are disclosed. Methods of retrofitting a water treatment system having an AOP by providing the electrochemical cell disclosed herein are disclosed.

A water production system with a thermal separation device that defines a cold region and a hot region, a fluid-air heat exchanger located remotely from the thermal separation device and exposed to air, and a fluid circulation loop that thermally connects the cold region of the thermal separation device to the fluid-air heat exchanger so as to cool the fluid-air heat exchanger and condense water from ambient air to produce water pure enough so that with further treatment it can be made potable. Also disclosed are filtration and dispensing features that are appropriate for a potable water supply.

Methods, apparatus, and systems are provided for detecting and removing microplastics from wastewater effluent. Both, automatic/remote and manual monitoring and sampling components are included to detect the presence of microplastics. The automatic monitoring and sampling component includes a TSS sensor and associated apparatus calibrated to account for non-plastic solids present in the wastewater and, thereby, more accurately determine the presence of microplastics. Efficient separation and removal of microplastics from wastewater effluent is performed by a specialized capture net apparatus having multiple sized mesh components and optional diffuser devices which perform size exclusion filtration of microplastics from the water. In an exemplary embodiment, the methods generally include diverting treated wastewater effluent from a wastewater treatment facility's main line into a wastewater sampling mechanism via an intake pipe, and then into a solids monitoring and separation mechanism which includes the specialized capture net apparatus.

A method for treating effluents containing nitrogen in the form of ammonium, implementing chemical reactions for oxidizing and reducing the nitrogen in a sequencing batch reactor, the method including: introducing a volume of effluents to be treated into the reactor, injecting oxygen or air into the reactor for partial oxidation of the ammonium into nitrites and/or nitrates, interrupting the injection of oxygen or air, thus producing gaseous nitrogen, depositing the sludge at the bottom of the reactor and clarifying the content of the reactor close to the surface of same, discharging a clarified fraction of the content of the reactor. The draining and feeding steps occur simultaneously. During the feeding step, the volume of effluents is introduced close to the bottom of the reactor. During the draining step, the clarified fraction of the content of the reactor is discharged close to the surface of the content of the reactor.

A unit (8) is intended for treating waste water. It includes a well (9) with an inlet conduit connector (21) and with an outlet conduit connector (22) at the outside of the well (9). The unit further includes a connecting conduit (20) inside the well (9). The connecting conduit (20) connects the inlet conduit connector (21) to the outlet conduit connector (22). There is at least one storage tank (13) inside the well (9) for a liquid chemical and a metering pump (18) inside the well (9) for pumping the chemical from the storage tank (13) into the connecting conduit (20). A control device (23) activates the metering pump according to a signal of a sensor (24) which senses a quantity of chemical element in the liquid flowing through the conduit (20).

A method and system of treating a liquid stream is provided. The water is treated by utilizing a free radical scavenging system and a free radical removal system. The free radical scavenging system can utilize actinic radiation with a free radical precursor compound, such as ammonium persulfate. The free radical removal system can comprise use of a reducing agent. The water may be further treated by utilizing ion exchange media and degasification apparatus. A control system may be utilized to measure and regulate addition of the precursor compound, the intensity of the actinic radiation, and addition of the reducing agent to the water.

A system for injecting an aqueous solution into an injection engine, includes: a tank for an aqueous solution, a circuit for supplying aqueous solution to the tank and a filter for filtering the aqueous solution, and a circuit for recirculating the aqueous solution. The injection system also includes recirculation of the aqueous solution, and is provided with an electrovalve including a first inlet connected to a filler neck of the tank, a second inlet connected to the recirculation circuit, and an outlet connected to the supply circuit. The filtration filter is arranged in the supply circuit and/or in the recirculation circuit.