A landfill gas recovery system includes a waste layer disposed in a landfill and a capping layer overlying the waste layer. The capping layer includes a cured sealing layer and a loose fill layer between the waste layer and the cured sealing layer. The loose fill layer includes a granular fill material. The cured sealing layer includes a composite of the granular fill material and a cured water soluble polymer. The cured sealing layer is substantially impermeable to landfill gases formed within the waste layer.

The invention disclosed a method for recycling rare earth elements from waste light-emitting electronic components by pyrolysis and alkaline melting-acid leaching. Based on the pyrolysis properties of the organic polymer, through catalytic pyrolysis of the organic polymer material in electronic components and convert the carbon in the residue into water gas, realize high-efficient dismantling of waste electronic component packaging materials. The traditional problems that the compositions of waste light-emitting electronic components are difficult to disassemble are solved, the generated pyrolysis gas and water gas can continuously supply energy for the pyrolysis system and recover the heat in the flue gas to save energy. Meanwhile, based on the chemical dissolution reaction mechanism of phosphors, the combination process of alkali melting, and acid leaching is used to efficiently recover rare earth elements from the waste light-emitting electronic components, and the step leaching of rare earth elements is realized. The rare earth oxalate can be recovered by precipitation, which greatly reduces the difficulty of late separation and purification.

The invention disclosed a method for recycling rare earth elements from waste light-emitting electronic components by pyrolysis and alkaline melting-acid leaching. Based on the pyrolysis properties of the organic polymer, through catalytic pyrolysis of the organic polymer material in electronic components and convert the carbon in the residue into water gas, realize high-efficient dismantling of waste electronic component packaging materials. The traditional problems that the compositions of waste light-emitting electronic components are difficult to disassemble are solved, the generated pyrolysis gas and water gas can continuously supply energy for the pyrolysis system and recover the heat in the flue gas to save energy. Meanwhile, based on the chemical dissolution reaction mechanism of phosphors, the combination process of alkali melting, and acid leaching is used to efficiently recover rare earth elements from the waste light-emitting electronic components, and the step leaching of rare earth elements is realized. The rare earth oxalate can be recovered by precipitation, which greatly reduces the difficulty of late separation and purification.

The purpose of the present invention is to provide a method which is for producing pulp fibers for cellulose nanofiberization from pulp fibers of used sanitary products, and which can produce pulp fibers for cellulose nanofiberization that have low lignin content and a low distribution thereof and that have excellent cellulose nanofiberization properties. This method is described below. The method is characterized by involving: a step for supplying, from a mixed solution supply port (32) to a treatment tank (31), a mixed solution (51) which contains superabsorbent polymers and pulp fibers derived from used sanitary products; a step for supplying an ozone-containing gas (53) from an ozone-containing gas supply port (43) to a treatment solution (52) inside of the treatment tank (31); a step in which, by raising the ozone-containing gas (53) while lowering the superabsorbent polymers and pulp fibers in the treatment tank (31), the ozone-containing gas (53) is brought into contact with the superabsorbent polymers and the pulp fibers, and pulp fibers for cellulose nanofiberization are formed from the pulp fibers; and a step for discharging the treatment solution (52) from a treatment solution discharge port (33), wherein the pulp fibers for cellulose nanofiberization have a lignin content of less than or equal to 0.1 mass %.

The purpose of the present invention is to provide a method which is for producing pulp fibers for cellulose nanofiberization from pulp fibers of used sanitary products, and which can produce pulp fibers for cellulose nanofiberization that have low lignin content and a low distribution thereof and that have excellent cellulose nanofiberization properties. This method is described below. The method is characterized by involving: a step for supplying, from a mixed solution supply port (32) to a treatment tank (31), a mixed solution (51) which contains superabsorbent polymers and pulp fibers derived from used sanitary products; a step for supplying an ozone-containing gas (53) from an ozone-containing gas supply port (43) to a treatment solution (52) inside of the treatment tank (31); a step in which, by raising the ozone-containing gas (53) while lowering the superabsorbent polymers and pulp fibers in the treatment tank (31), the ozone-containing gas (53) is brought into contact with the superabsorbent polymers and the pulp fibers, and pulp fibers for cellulose nanofiberization are formed from the pulp fibers; and a step for discharging the treatment solution (52) from a treatment solution discharge port (33), wherein the pulp fibers for cellulose nanofiberization have a lignin content of less than or equal to 0.1 mass %.

The present invention is a method for treating an alloy, by which a solution that contains nickel and/or cobalt is obtained from an alloy that contains copper, zinc, and nickel and/or cobalt, said method comprising: a leaching process wherein a leachate is obtained by subjecting the alloy to a leaching treatment by means of an acid in the coexistence of a sulfurizing agent; a reduction process wherein the leachate is subjected to a reduction treatment with use of a reducing agent; and an ion exchanging process wherein a solution that contains nickel and/or cobalt is obtained by bringing a solution, which has been obtained in the reduction process, into contact with an amino phosphoric acid-based chelate resin, thereby having zinc adsorbed on the amino phosphoric acid-based chelate resin.

A landfill gas recovery system includes a waste layer disposed in a landfill and a capping layer overlying the waste layer. The capping layer includes a cured sealing layer and a loose fill layer between the waste layer and the cured sealing layer. The loose fill layer includes a granular fill material. The cured sealing layer includes a composite of the granular fill material and a cured water soluble polymer. The cured sealing layer is substantially impermeable to landfill gases formed within the waste layer.

The present invention relates generally to the field of waste processing. The method comprises separating waste into at least two parts, comprising: (i) mainly food waste (fines) and (ii) mainly paper and other recyclable material (overs). The overs are pulped and washed to obtain a cellulose-rich biomass and the fines are optionally processed separately to recover a cellulose-rich biomass and the cellulose-rich biomass from both the fines and the overs may be combined.

The present invention relates generally to the field of waste processing. The method comprises separating waste into at least two parts, comprising: (i) mainly food waste (fines) and (ii) mainly paper and other recyclable material (overs). The overs are pulped and washed to obtain a cellulose-rich biomass and the fines are optionally processed separately to recover a cellulose-rich biomass and the cellulose-rich biomass from both the fines and the overs may be combined.

A system for processing a waste lithium-ion battery includes: a first aqueous solution generator that includes a first elution tank storing water, and that immerses an active material taken out from the waste lithium-ion battery in the water in the first elution tank and subjects the active material to carbon dioxide bubbling in the first elution tank to generate an aqueous solution of pH 5.5 to 8.5, in which lithium contained in the active material is eluted; a first solid-liquid separator that removes a solid component from the aqueous solution generated by the first aqueous solution generator; a first crystallizer that causes lithium carbonate to be deposited from the aqueous solution, from which the solid component has been removed by the first solid-liquid separator; and a second solid-liquid separator that performs solid-liquid separation on slurry containing the lithium carbonate deposited in the first crystallizer to take out the lithium carbonate.