Disclosed herein is a method for removing contaminants from an industrial fluid waste. The method comprises the steps of ozofractionating the industrial fluid waste whereby contaminants are oxidised and a foam fractionate is formed; and separating at least a portion of the foam fractionate and any precipitate from the ozofractionated fluid.

A method of treating a waste liquid includes: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and performing separation into a first treated water and a reduced heavy metal precipitate; a gypsum recovery step of adding a calcium compound to the first treated water at a liquid property of a pH of 4 or less, and performing separation into a second treated water and gypsum; an aluminum and fluorine removal step of adding an alkali to the second treated water and performing separation into a third treated water and a precipitate containing aluminum and fluorine; and a neutralization step of adding an alkali to the third treated water and performing separation into an alkali neutralization treated water and a neutralized precipitate of a heavy metal hydroxide.

A method for electrolysis-ozone-corrosion inhibitor/electrolysis-ozone-hydrogen peroxide-corrosion inhibitor coupling treatment on toxic and refractory wastewater includes the following steps: adding toxic and refractory wastewater to be treated into a wastewater treatment reaction tank equipped with a plate anode and a plate cathode, and starting a direct current (DC) power supply connected to the plate anode and the plate cathode to treat the toxic and refractory wastewater at an appropriate current density under stirring, during which a corrosion inhibitor and hydrogen peroxide are added to the toxic and refractory wastewater to be treated and ozone is introduced into the toxic and refractory wastewater to be treated through an aeration device. The method can increase the production rate and production quantity of free radicals in a reaction system, effectively improve the treatment efficiency for toxic and refractory wastewater, and reduce the treatment cost.

A method and system is provided for treating waste generated from manufacturing operations including at least one of Printed Circuit Boards Fabrication (PCB FAB), General Metal Finishing (GMF), semiconductors manufacturing, chemical milling, and Physical Vapour Deposition (PVD). The method and system are used to create zero liquid discharge recycling.

A method of treating a waste liquid: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and performing separation into a first treated water and a reduced heavy metal precipitate; a gypsum recovery step of adding a calcium compound to the first treated water at a pH of 4 or less, and performing separation into a second treated water and gypsum; a heavy metal coprecipitation step of adding a ferric compound to the second treated water and performing separation into a third treated water and a heavy metal coprecipitate; an aluminum and fluorine removal step of adding an alkali to the third treated water and performing separation into a fourth treated water and a precipitate containing aluminum and fluorine; and a neutralization step of adding an alkali to the fourth treated water and performing separation into an alkali neutralization treated water and a neutralized heavy metal hydroxide.

A method for processing a metallurgical waste acid, includes the following steps. First, a certain amount of a metallurgical waste acid is added into a reaction kettle. Then, the metallurgical waste acid and magnesium slag are added into the reaction kettle in a weight ratio ranging from 5:1 to 15:1 and are stirred into a mixed waste water. The reaction temperature is the room temperature. Then, a certain amount of sulfuric acid is added into the reaction kettle to control the mixed waste water within a pH range. At last, the mixed waste water is filtered.

A method for preparing a nanofiltration membrane and a nanofiltration membrane prepared therefrom, the method comprising the following steps: dissolving a polymer in a solvent to prepare a polymer solution, and curing the polymer solution on a support material to form a base membrane; sequentially applying a first liquid-phase solution and a second liquid-phase solution on the base membrane to form a nascent membrane; densifying the nascent membrane by using a solution that contains an alkaline substance; processing the densified nascent membrane by using a solution that contains an acidic substance; and obtaining the nanofiltration membrane after post-processing and drying.

Methods and compositions for inhibiting corrosion of a metal product are provided. The metal product can be contacted with water that includes at least one carbonate and/or bicarbonate salt, or otherwise has components that increase the alkalinity of the water. In addition, or as an alternative, the water can include a stannous corrosion inhibitor. The water can be evaporated off of a surface of the metal product to provide a residual of the salt on the surface and/or a protective stannous film on the surface.

A method and system is provided for treating waste generated from manufacturing operations including at least one of Printed Circuit Boards Fabrication (PCB FAB), General Metal Finishing (GMF), semiconductors manufacturing, chemical milling, and Physical Vapour Deposition (PVD). The method and system are used to create zero liquid discharge recycling.

A waste liquid treating device includes a holding section that holds an adhesion plate, a vertically moving mechanism that moves the holding section vertically, and a peeling mechanism that peels off water-containing swarf from the adhesion plate held by the holding section. The peeling mechanism includes two air nozzles extending in parallel to each other in a horizontal direction with a spacing therebetween and including jet ports formed to face each other, a valve disposed in a piping providing communication between the two air nozzles and an air source, and a control unit that performs control of opening and closing of the valve and control of the vertically moving mechanism for moving the adhesion plate in the vertical direction in the spacing between the two air nozzles.