An object of the present invention is to provide a chemical liquid which has excellent defect inhibition performance and hardly breaks a transfer pipe line that a device for manufacturing the chemical liquid includes at the time of manufacturing the chemical liquid. Another object of the present invention is to provide a chemical liquid storage body, a manufacturing method of a chemical liquid, and a manufacturing method of a chemical liquid storage body. The chemical liquid according to an embodiment of the present invention is a chemical liquid containing an organic solvent and an ion of at least one kind of atom selected from the group consisting of an Fe atom, a Cr atom, a Ni atom, and a Pb atom, in which in a case where the chemical liquid contains one kind of the ion, a content of the metal ion is 0.1 to 100 mass ppt, in a case where the chemical liquid contains two or more kinds of the ions, a content of each of the metal ions is 0.1 to 100 mass ppt, and a charge potential is equal to or lower than 100 mV.

The water treatment device according to the present disclosure includes: an electrochemical cell having electrodes including a positive electrode and a negative electrode, and a bipolar membrane; a tank; a power supply configured to apply power to the electrodes; a water circulation flow path having at least the tank and the electrochemical cell and through which water circulates; a circulation device configured to circulate water in the water circulation flow path; a raw water supply path configured to supply raw water to the water circulation flow path; and a control device. In performing water softening treatment in the electrochemical cell where power is applied to the electrodes so as to remove ions from raw water and soft water is produced, the control device drives the circulation device so as to circulate water in the water circulation flow path.

A method for controlling a membrane distillation system includes determining whether there is a day time or a night time at a location of a solar collector system associated with the membrane distillation system; applying a first control mode during the day time to a flow velocity of a feed used by the membrane distillation system; and applying a second control mode, different from the first control scheme, during the night time, to the feed. The first control scheme is a model-free mode.

An object of the present invention is to provide a chemical liquid which has excellent defect inhibition performance and hardly breaks a transfer pipe line that a device for manufacturing the chemical liquid includes at the time of manufacturing the chemical liquid. Another object of the present invention is to provide a chemical liquid storage body, a manufacturing method of a chemical liquid, and a manufacturing method of a chemical liquid storage body. The chemical liquid according to an embodiment of the present invention is a chemical liquid containing an organic solvent and an ion of at least one kind of atom selected from the group consisting of an Fe atom, a Cr atom, a Ni atom, and a Pb atom, in which in a case where the chemical liquid contains one kind of the ion, a content of the metal ion is 0.1 to 100 mass ppt, in a case where the chemical liquid contains two or more kinds of the ions, a content of each of the metal ions is 0.1 to 100 mass ppt, and a charge potential is equal to or lower than 100 mV.

The water treatment device according to the present disclosure includes: an electrochemical cell having electrodes including a positive electrode and a negative electrode, and a bipolar membrane; a tank; a power supply configured to apply power to the electrodes; a water circulation flow path having at least the tank and the electrochemical cell and through which water circulates; a circulation device configured to circulate water in the water circulation flow path; a raw water supply path configured to supply raw water to the water circulation flow path; and a control device. In performing water softening treatment in the electrochemical cell where power is applied to the electrodes so as to remove ions from raw water and soft water is produced, the control device drives the circulation device so as to circulate water in the water circulation flow path.

The formation of scale in a reverse osmosis membrane apparatus is reduced at low water temperatures without the necessity of pH adjustment or addition of a scale dispersant to continue a consistent operation for a long period of time. The operation of a reverse osmosis membrane apparatus is controlled on the basis of the concentration of aluminum ions and/or iron ions in the feed to the reverse osmosis membrane apparatus and/or the concentrate from the reverse osmosis membrane apparatus. Not only silica but also aluminum ions and iron ions that are also present in the water significantly affect the reduction in the flux of a reverse osmosis membrane which is caused by silica scale. It is necessary to appropriately control the concentration of aluminum ions and/or iron ions in the feed and/or the concentrate to consistently operate a reverse osmosis membrane apparatus for a long period of time.

A system and process for removing divalent ions from a MEG feed stream is presented. Embodiments of the system include a chemical treatment tank where chemicals are mixed with the feed stream to form insoluble carbonate and hydroxide salts. The system also includes a solid-liquid separation unit that receives the feed stream from the chemical treatment tank and separates it into a liquids portion containing MEG and a insoluble salts portion. The system may also include washing the insoluble salts portion to remove additional MEG, which is then recycled to a MEG regeneration or reclamation process. The system may also include a dryer that receives waste slurry from the solid-liquid separation unit and dries it to form a solid waste, thereby facilitating its handling, storage, and disposal.

A process for separating a gaseous or liquid mixture by means of a separating device including a first volume and a second volume which are separated by a membrane which has selective permeability with respect to at least two components of the mixture, comprising the following steps: a) fill up the first volume of the device with the mixture to be separated; b) wait for a period of time which is in excess of the permeation lag time, but is insufficient to reach a state of equilibrium, during which time a fraction of each component of the mixture passes from the first to the second volume of the device through the membrane; and c) evacuate the first and the second volume of the device, as a result of which at least one first and one second cut of the mixture is obtained, having different molar compositions.

A system and process for removing divalent ions from a MEG feed stream is presented. The system includes a chemical treatment tank where chemicals are mixed with the feed stream to form insoluble carbonate and hydroxide salts. The system also includes a solid-liquid separation unit that receives the feed stream from the chemical treatment tank and separates it into a liquids portion containing MEG and a insoluble salts portion. The system may also include washing the insoluble salts portion to remove additional MEG, which is then recycled to a MEG regeneration or reclamation process. The system may also include a dryer that receives waste slurry from the solid-liquid separation unit and dries it to form a solid waste, thereby facilitating its handling, storage, and disposal.

A water purification apparatus receives raw water, which sequentially passes through a pre-filter, a pump, an RO filter, and a post-filter and is stored in the post-filter as drinking water. A recirculating water loop is in fluid communication with the post-filter and the pump to facilitate flow of the drinking water. A water quality detector generates a water quality signal corresponding to a quality value of the drinking water. A control valve is in fluid communication with the recirculating water loop. A controller receives the water quality signal and is stored with a water quality standard and a recirculation period. When a water discharging member stops discharge of the drinking water and the quality value exceeds the water quality standard, the controller activates the pump and the control valve, such that the drinking water in the post-filter recirculates through the recirculating water loop and is re-purified.