A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

A method of treating an animal skin substrate comprising: agitating the animal skin substrate with a solid particulate material and a treatment liquor; separating the animal skin substrate from effluent comprising the solid particulate material, the treatment liquor and solid waste fragments derived from said substrate; transferring the effluent to a first separator, wherein the first separator is configured to allow the treatment liquor and at least a portion of the solid waste fragments to pass through the first separator but to prevent the solid particulate material from passing through the first separator, and providing a first filtrate stream comprising treatment liquor and solid waste fragments and a first residue comprising solid particulate material and residual solid waste fragments treating said first residue to remove said residual solid waste fragments to provide cleaned solid particulate material, wherein said treating of said first residue comprises retaining said solid particulate material on a surface of a treatment separator during said treating, wherein the treatment separator is configured to allow liquid and residual solid waste fragments to pass through but to prevent the solid particulate material from passing through; and (i) directing a cleaning formulation onto said solid particulate material to provide a second filtrate stream comprising said cleaning formulation and said residual solid waste fragments and a second residue comprising cleaned solid particulate material; and/or (ii) agitating the treatment separator.

The present invention relates to method/process of synthesis for ferrate synthesis. More specifically, it includes method for producing a liquid ferrate solution of oxidation of plus 6 stage, and discusses the apparatus and the raw materials and an improved greener process for synthesizing stable, high purity ferrate (VI) used for treating wastewater. The synthesis method involves three stages, namely, oxidation of hematite ore, followed by ferrate with chlorine under alkaline conditions and addition of stabilizing agent to improve shelf life of liquid ferrate solution for minimum 6 weeks. The process results in the efficient and effective productions of ferrate with high yields and small amounts of waste production. The synthesized chemical ferrate (VI) through the present invention has resulted in the effective reduction of BOD, COD and TSS.

The present invention provides phosphonium-crosslinked chitosan (PCC) and methods for using the same for removal of heavy metal-ion(s) from a solution as well as methods for producing said phosphonium-crosslinked chitosan.

A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

Embodiments described herein generally relate to humidification-dehumidification desalination systems, including apparatuses that include a vessel comprising a humidification region (e.g., a bubble column humidification region) and a dehumidification region (e.g., a bubble column dehumidification region), mobile humidification-dehumidification (HDH) desalination systems (e.g., systems having a relatively low height and/or a relatively small footprint), and associated systems and methods. Certain embodiments generally relate to methods of operating, controlling, and/or cleaning desalination systems comprising a plurality of desalination units (e.g., HDH desalination units).

A method to prepare a haloamine, such as a monochloramine in solution, from a solid halogen releaser(s) is described. Also described is a process to form a haloamine in solution using solid reactants. Also, an aqueous haloamine, such as a monochloramine solution, is further described that has a haloamine in solution and a dehalogenated organic compound present. Methods of use are also described.

A method of treating a substrate with a solid particulate material and a treatment liquor comprising: agitating the substrate with said solid particulate material and said treatment liquor; and (a) separating the substrate from effluent comprising solid waste fragments derived from the substrate, said solid particulate material and the treatment liquor; (b) transferring said effluent to a hydrocyclone separator comprising an inlet, a first outlet and a second outlet, wherein the effluent is fed into the hydrocyclone separator via the inlet; (c) separating the effluent in the hydrocyclone separator to produce a first stream and a second stream, wherein the first stream comprises said solid particulate material and exits the hydrocyclone separator via the first outlet and wherein the second stream comprises treatment liquor and solid waste fragments and exits the hydrocyclone separator via the second outlet; and (d) collecting the first stream after it exits the hydrocyclone separator via the first outlet.

The present invention provides phosphonium-crosslinked chitosan (PCC) and methods for using the same for removal of heavy metal-ion(s) from a solution as well as methods for producing said phosphonium-crosslinked chitosan.

A method of treating an animal skin substrate comprising: agitating the animal skin substrate with a solid particulate material and a treatment liquor; separating the animal skin substrate from effluent comprising the solid particulate material, the treatment liquor and solid waste fragments derived from said substrate; transferring the effluent to a first separator, wherein the first separator is configured to allow the treatment liquor and at least a portion of the solid waste fragments to pass through the first separator but to prevent the solid particulate material from passing through the first separator, and providing a first filtrate stream comprising treatment liquor and solid waste fragments and a first residue comprising solid particulate material and residual solid waste fragments treating said first residue to remove said residual solid waste fragments to provide cleaned solid particulate material, wherein said treating of said first residue comprises retaining said solid particulate material on a surface of a treatment separator during said treating, wherein the treatment separator is configured to allow liquid and residual solid waste fragments to pass through but to prevent the solid particulate material from passing through; and (i) directing a cleaning formulation onto said solid particulate material to provide a second filtrate stream comprising said cleaning formulation and said residual solid waste fragments and a second residue comprising cleaned solid particulate material; and/or (ii) agitating the treatment separator.