摘要:
Disclosed are methods and compositions for coagulating and clarifying produced waters for use as boiler feed waters, for example for the generation of steam. The methods and compositions are especially useful for treatment of produced waters from steam-injection methods of tertiary oil recovery such as steam-assisted gravitational drainage. Disclosed are compositions comprising a first copolymer having a high molecular weight and bearing a low molar cationic charge and a second copolymer having a lower molecular weight and bearing a high molar cationic charge. The compositions are suitable for addition as coagulants to produced waters that have been treated by warm lime softening. Also disclosed are methods of treating produced waters from steam-injection oil recovery for use as boiler feed waters to generate steam in such steam injection methods.
摘要:
The present invention is in the field of an improved method for recovery of phosphorous, in particular of phospho¬ rous from a waste stream, and to a product obtained thereby. The product is in a form wherein phosphorous can be released to e.g. the soil and plants at a desired amount per interval of time.
摘要:
Disclosed herein is a method for treating an alkaline brine. The method comprises adding a source of magnesium ions to the alkaline brine. A resultant magnesium-containing precipitate is separated to produce a spent brine. If the spent brine contains a sufficient amount of carbonate or bicarbonate ions, the spent brine is processed to recover a carbonate product.
摘要:
The invention relates to a process for the removal of contaminants from a liquor, the process comprising: introducing a metal or ammonium hydroxide into the liquor; introducing the liquor into a reaction vessel; bubbling a carbon dioxide gas comprising at least 25% carbon dioxide through the liquor within the reaction vessel; and separating the precipitate formed by the carbonatation of the metal hydroxide from the liquor, the precipitate comprising at least some of the contaminants from the liquor; wherein, on average, the liquor is resident within the reaction vessel for a period of no more than about 60 minutes and wherein the size of the precipitate may be at least partially controlled or controllable by altering the residence time of the liquor in the reaction vessel or the p H of the liquor in the reaction vessel. The invention also relates to a process for the removal of contaminants from a liquor, the process comprising: introducing a metal or ammonium hydroxide into the liquor and bubbling a carbon dioxide gas comprising at least 25% carbon dioxide through the liquor to form a precipitate by carbonatation in a period of no more than about 60 minutes and wherein the size of the precipitate may be at least partially controlled or controllable by altering the residence time of the liquor in the reaction vessel or the p H of the liquor in the reaction vessel. The carbonatation processes may be included in sugar refining or water softening and/or decontamination processes. A use of a carbon dioxide gas comprising at least 25% carbon dioxide in a carbonatation process for removing contaminants from a hydroxide-treated liquor is also provided, wherein the process forms a precipitate in a period of no more than about 60 minutes and wherein the size of the precipitate may be at least partially controlled or controllable by altering the residence time of the liquor in the reaction vessel or the p H of the liquor in the reaction vessel.
摘要:
The invention relates to a method for processing sulphate-containing water. The method contains stages in which sulphate-containing water is directed to an anaerobic bioreactor, and an anaerobic bacterial strain that converts sulphate to hydrogen sulphide converts the sulphate contained in the water to hydrogen sulphide gas. The resulting hydrogen sulphide gas is directed for incineration in a hydrogen sulphide incineration unit, which produces combustion gases containing sulphur dioxide. Energy released at various stages in the process is recovered and reused in the same process. The residual water is removed from the bioreactor.
摘要:
Vorgeschlagen wird ein Entcarbonisierungsverfahren zum Gewinnen von in seiner Carbonathärte reduziertem klarem Betriebswasser aus Rohwasser mit einer Carbonathärte von zumindest 1,3 mmol/1, mit den folgenden Verfahrensschritten : - Versetzen des Rohwassers mit einer wässrigen Calciumhydroxidlösung in einem vorgegebenen Mischungsverhältnis, um Calciumcarbonat (CaCO 3 ) im Wege einer Fällungsreaktion aus dem Rohwasser auszufällen, - Zuführen des entcarbonisierten Rohwassers an eine Vorrichtung zur Membranfiltration, um das aus dem Rohwasser ausgefällte Calciumcarbonat herauszufiItern. Erfindungsgemäß wird das mit der Calciumhydroxidlösung versetzte Rohwasser innerhalb einer mittleren Verweilzeit von T ≤ 6 Minuten bei einem definierten Druck größer Atmosphärendruck innerhalb eines Rohrleitungssystems (18) strömend geführt und unter Ablauf der Fällungsreaktion entcarbonisiert. Die Erfindung betrifft weiterhin eine Vorrichtung (10) zum Durchführen des erfindungsgemäßen Entcarbonisierungsverfahrens.
摘要:
A method of reducing a sulfate concentration in wastewater comprises directing the wastewater stream to a precipitation reactor and mixing the wastewater stream with a calcium source and a calcium salt seed material to precipitate calcium sulfate. The precipitated calcium sulfate is then separated from a treated effluent and directed to a settling tank where the precipitated calcium sulfate is separated into heavier calcium sulfate precipitants and lighter calcium sulfate precipitants. The heavier calcium sulfate precipitants and the lighter calcium sulfate precipitants are separately recirculated to the precipitation reactor. A predetermined mass ratio of solids is maintained in the precipitation reactor.
摘要:
A warewashing composition includes a cleaning agent having a detersive amount of a surfactant, an alkaline source in an amount effective to provide a use composition having a pH of at least about 8 when the use composition is measured at a solids concentration of about 0.5 wt%, and a corrosion inhibitor in an amount sufficient for reducing corrosion of glass when the warewashing composition is combined with water of dilution at a dilution ratio of at least about 20:1 water of dilution to detergent composition to form a use composition. The corrosion inhibitor includes a salt of calcium, magnesium, or a mixture of calcium and magnesium. The salt has a water solubility of less than about 0.5 wt% in water at about 20°C and atmospheric pressure so that the salt precipitates to form a protective layer on a substrate in contact with the use composition.