The present invention provides processes for filtering undesired chemicals in streams of contaminated air for supply to confined areas. The processes provide (1) contacting air with a filter comprising by volume from about 5% to about 95% impregnated zirconium hydroxide, from about 5% to about 95% activated impregnated carbon, and optionally, up to about 50% ammonia removal material; and (2) supplying the contacted air to a confined area.

The present disclosure is directed to methods for treating an organic material, including the steps of transporting the organic material into a first vessel; heating the organic material in the first vessel and applying a negative pressure to the organic material in the first vessel to a boiling point of the organic material, wherein the heat and negative pressure separates a portion of an ammonia from the organic material; removing the portion of the ammonia from the first vessel; transporting the removed portion of the ammonia from the first vessel to an acid solution in a second vessel; and separating a portion of the ammonia from the acid solution.

This invention relates to a Cu-BTC MOF which is water stable. The Cu-BTC MOF has been modified by substituting some of the BTC ligand (1,3,5, benzene tricarboxylic acid) with 5-aminoisophthalic acid (AIA). The resultant MOF retains at least 40% of its as synthesized surface area after exposure to liquid water at 60° C. for 6 hours. This is an unexpected result versus the MOF containing only the BTC ligand. This MOF can be used to abate contaminants such as ammonia in gas streams and especially air streams.

This invention relates to a Cu-BTC MOF which is water stable. The Cu-BTC MOF has been modified by substituting some of the BTC ligand (1,3,5, benzene tricarboxylic acid) with 5-aminoisophthalic acid (AIA). The resultant MOF retains at least 40% of its as synthesized surface area after exposure to liquid water at 60° C. for 6 hours. This is an unexpected result versus the MOF containing only the BTC ligand. This MOF can be used to abate contaminants such as ammonia in gas streams and especially air streams.

A urea granulation process with a scrubbing system may involve at least one gaseous waste stream for removal of dust and ammonia whereby the waste stream may be processed through a combination of process steps. In some examples, the process steps may involve washing the dust and ammonia laden stream with water and/or an aqueous urea solution whereby a dust-laden liquid stream and a dust-reduced stream is generated. The process steps may further involve reacting the dust-reduced stream with formaldehyde to form a stream comprising hexamethylenetetramine and urea-formaldehyde and clean off-gas. In some cases, the gas stream may be directed first through the washing step and then through the reacting step.

A urea granulation process with a scrubbing system may involve at least one gaseous waste stream for removal of dust and ammonia whereby the waste stream may be processed through a combination of process steps. In some examples, the process steps may involve washing the dust and ammonia laden stream with water and/or an aqueous urea solution whereby a dust-laden liquid stream and a dust-reduced stream is generated. The process steps may further involve reacting the dust-reduced stream with formaldehyde to form a stream comprising hexamethylenetetramine and urea-formaldehyde and clean off-gas. In some cases, the gas stream may be directed first through the washing step and then through the reacting step.

Disclosed is a urea finishing method including an off-gas treatment, the method comprising urea finishing and supplying the off-gas to a quenching zone and to a scrub column comprising a sump and a venturi stage, wherein the sump has a split sump configuration with two compartments.

Disclosed is a urea finishing method including an off-gas treatment, the method comprising urea finishing and supplying the off-gas to a quenching zone and to a scrub column comprising a sump and a venturi stage, wherein the sump has a split sump configuration with two compartments.

A process for purification of waste from zootechnical sources or from small agri-food companies is provided. A plant for carrying out the wastewater treatment process is also provided.

A method for removing at least one contaminant from a fluid stream by filtering the fluid stream with a filtration medium. The filtration medium includes an impregnate. The impregnate includes a surfactant such as sulfamic acid. The medium has from about 0.1 to about 25% by weight of impregnate. The method is useful for removing one or more volatile organic compounds, particularly formaldehyde, from the fluid stream. In some embodiments, the method includes removing at least two volatile organic compound contaminants from the fluid stream.