Abstract: A method is provided for recycling and treating the wastes of silicon wafer cutting and polishing processes. To begin with, a dewatered filter cake is mixed with water so that the filter cake is diluted to form a working fluid. The water reacts with silicon in the filter cake to produce silicon dioxide and hydrogen. After the hydrogen is extracted for storage, specific gravity separation takes place via water so that silicon carbide and silicon particles are separated for sorting. Then, solid-liquid separation is performed on the remaining working fluid to separate silicon dioxide (solid) from water and PEG (liquid), before PEG is separated from water. Thus, the useful silicon particles, silicon carbide, silicon dioxide, and PEG are recycled from the filter cake to reduce the total amount of wastes. Moreover, as the side product, hydrogen, is of high commercial value, the method also adds value to recycling.

Abstract: A method and system for recycling and treating dyeing wastewater are provided. To begin with, the dyeing wastewater is added with an adsorbent for assisted decolorization and filtration. Then, the wastewater is filtered with a first filtration device having hydrophilic membranes. The liquid having passed through the hydrophilic membranes undergoes an RO membrane-base filtration process to produce recycled water and concentrated wastewater. The concentrated wastewater is delivered into a second filtration device having hydrophobic membranes, before a micro-bubbling process is performed on the concentrated wastewater in the second filtration device to turn the concentrated wastewater into a creamy-white nebulized working liquid of high gas content. The steam in the working liquid can readily pass through the hydrophobic membranes to produce an effluent that meets effluent standards.

Abstract: A method is provided for recycling and treating the wastes of silicon wafer cutting and polishing processes. To begin with, a dewatered filter cake is mixed with water so that the filter cake is diluted to form a working fluid. The water reacts with silicon in the filter cake to produce silicon dioxide and hydrogen. After the hydrogen is extracted for storage, specific gravity separation takes place via water so that silicon carbide and silicon particles are separated for sorting. Then, solid-liquid separation is performed on the remaining working fluid to separate silicon dioxide (solid) from water and PEG (liquid), before PEG is separated from water. Thus, the useful silicon particles, silicon carbide, silicon dioxide, and PEG are recycled from the filter cake to reduce the total amount of wastes. Moreover, as the side product, hydrogen, is of high commercial value, the method also adds value to recycling.

Abstract: A method and system for recycling and treating dyeing wastewater are provided. To begin with, the dyeing wastewater is added with an adsorbent for assisted decolorization and filtration. Then, the wastewater is filtered with a first filtration device having hydrophilic membranes. The liquid having passed through the hydrophilic membranes undergoes an RO membrane-base filtration process to produce recycled water and concentrated wastewater. The concentrated wastewater is delivered into a second filtration device having hydrophobic membranes, before a micro-bubbling process is performed on the concentrated wastewater in the second filtration device to turn the concentrated wastewater into a creamy-white nebulized working liquid of high gas content. The steam in the working liquid can readily pass through the hydrophobic membranes to produce an effluent that meets effluent standards.