A method of processing pulp, extracted from red mud in processing bauxite, includes the following steps. The pulp is filtered to obtain a first filter cake and a first filtrate. Aluminum is leached from the first filter cake by adding, to the first filter cake, sodium hydroxide (NaOH) solution to form an aluminum-containing first slurry. The first slurry is filtered to obtain an aluminum-containing second filter cake and a second filtrate. From the second filtrate, in presence of carbon dioxide gas, first aluminum compounds are filtered out. Aluminum is leached out from the second filter cake by adding, to the second filter cake, NaOH solution to form a second slurry. The second slurry is filtered to obtain a third filter cake and an aluminum-containing third filtrate. From the third filtrate, second aluminum compounds are precipitated out which include sodium hydroaluminocarbonate and aluminum hydroxide.

A method, and an installation thereof, for recovering phosphorus from sludge to be treated, said method including: a stage of pre-acidification of said sludge to be treated including a step of adding an acid, preferably carbon dioxide into said sludge to be treated; a stage of bio-acidification including a step of acidogenesis and carried out in a reactor having a hydraulic retention time comprised between 1 day to 8 days and, wherein the acidified sludge has a pH comprised between 3.5 to 5.5; and a stage of treatment including: a step of solid/liquid separation; and a step of recovery of phosphates in liquid phase by sorption and/or crystallization, giving a phosphorus depleted water.

A method for treating acrolein reactor wastewater, comprising the steps of: S1. mixing acrolein reactor wastewater and a carbonate aqueous solution to obtain a mixed solution, wherein the acrolein reactor wastewater has a pH value of less than 2 and contains 500 ppm to 3,000 ppm of acrolein, 50 ppm to 800 ppm of allyl alcohol, 40,000 ppm to 100,000 ppm of acrylic acid, 10,000 ppm to 30,000 ppm of formaldehyde, 3,000 ppm to 10,000 ppm of acetic acid and 3,000 ppm to 8,000 ppm of maleic acid; and the mixed solution has a pH value of 4 to 6, a COD concentration ranging from 7,500 ppm to 30,000 ppm, and a formaldehyde concentration ranging from 800 ppm to 4,000 ppm; S2. conveying the mixed solution obtained in step S1 to an anaerobic reactor (4) for biochemical treatment; and S3. conveying the solution treated in step S2 to an aerobic biochemical tank (5) for treatment; and reflowing at least one part of the solution treated in step S2 and/or S3 to step S2. Also provided is a device for treating acrolein reactor wastewater.

Provided herein is a method for anaerobically fermenting an organic solid waste, including: subjecting the organic solid waste to anaerobic fermentation under catalysis of a zirconium-based metal organic framework (MOF) material.

Provided herein is a method for anaerobically fermenting an organic solid waste, including: subjecting the organic solid waste to anaerobic fermentation under catalysis of a zirconium-based metal organic framework (MOF) material.

An apparatus, method and system is provided for treating sewage sludge by dewatering the sewage sludge, heating the sewage sludge being treated to destroy pathogens, and then reducing volatile solids in the sewage sludge being treated through biochemical decomposition to produce a treated biosolids product that meets government regulations for pathogen reduction and vector attraction reduction.

An apparatus, method and system is provided for treating sewage sludge by dewatering the sewage sludge, heating the sewage sludge being treated to destroy pathogens, and then reducing volatile solids in the sewage sludge being treated through biochemical decomposition to produce a treated biosolids product that meets government regulations for pathogen reduction and vector attraction reduction.

A technique, method and system for drying a solid waste stream in a pyrolysis recycling installation, including drying the waste stream in a first dryer, feeding the partially dried waste stream from the first dryer to a second dryer, further drying the waste stream in the second dryer to produce a dried waste stream, and feeding the dried waste stream from the second dryer to a pyrolysis unit, wherein the first and second dryers dry the waste stream primarily, or exclusively, using heat generated from the pyrolysis unit.

A technique, method and system for drying a solid waste stream in a pyrolysis recycling installation, including drying the waste stream in a first dryer, feeding the partially dried waste stream from the first dryer to a second dryer, further drying the waste stream in the second dryer to produce a dried waste stream, and feeding the dried waste stream from the second dryer to a pyrolysis unit, wherein the first and second dryers dry the waste stream primarily, or exclusively, using heat generated from the pyrolysis unit.

This specification describes systems and methods for treating wastewater, for example digestate. The wastewater is separated into a liquid fraction and a solid fraction. The solid fraction of the wastewater is composted. The liquid fraction of the wastewater can be treated, which may result in further by-products. Optionally, at least some of the liquid fraction may be reused in the process. The by-products produced in treating the liquid fraction and/or additional organic solid waste, for example green waste, brought into the treatment facility can be added to the compost. The compost breaks down through aerobic and/or anaerobic digestion processes. Thermophilic conditions may develop in composting piles and increase the rate of evaporation of excess water. When sufficiently dry, the compost may be used as a fertilizer or soil enhancement product.