The present invention provides a method for the production of a metal halide adduct of S.sub.4N.sub.4, in particular a specific copper adduct of S.sub.4N.sub.4, for the visualisation of a print on an object, in particular a fingerprint on a metal object. The present invention also provides a method and apparatus for visualising a print on an object, using S.sub.2N.sub.2 obtained from a metal halide adduct of S.sub.4N.sub.4.

Embodiments described herein provide systems and methods for a phosphate processing system with integrated sub-systems, such as a phosphoric acid plant, precipitation system, crystallizer system, rinsing system, granulation system, pond water system, organics removal system, and/or exhaust treatment system. Such sub-systems can be integrated with each other by using one or more output streams from one or more sub-systems as one or more input streams for one or more sub-systems. In some embodiments, the phosphate processing system can produce phosphoric acid, struvite containing fertilizer, fertilizer using recycled struvite, magnesium or fluoride containing compositions using recycled magnesium or fluoride, and other components using phosphoric acid collected from a phosphoric acid and gypsum composition or using sludge collected from a waste stream, for example.

The present invention relates to a method for purifying raw phosphoric acid by adding ashes originating from waste incineration plants, as well as calcium hydroxide and at least one sulfide, and by wet-chemical digestion for obtaining (producing) calcium sulfate, pure phosphoric acid, metal salt solution and/or calcium hydrogen phosphates (e.g. triple superphosphate).

The present invention relates to a method for purifying raw phosphoric acid by adding ashes originating from waste incineration plants, as well as calcium hydroxide and at least one sulfide, and by wet-chemical digestion for obtaining (producing) calcium sulfate, pure phosphoric acid, metal salt solution and/or calcium hydrogen phosphates (e.g. triple superphosphate).

The present invention provides a method for the production of a metal halide adduct of S.sub.4N.sub.4, in particular a specific copper adduct of S.sub.4N.sub.4, for the visualisation of a print on an object, in particular a fingerprint on a metal object. The present invention also provides a method and apparatus for visualising a print on an object, using S.sub.2N.sub.2 obtained from a metal halide adduct of S.sub.4N.sub.4.

The present invention provides a method for the production of a metal halide adduct of S.sub.4N.sub.4, in particular a specific copper adduct of S.sub.4N.sub.4, for the visualisation of a print on an object, in particular a fingerprint on a metal object. The present invention also provides a method and apparatus for visualising a print on an object, using S.sub.2N.sub.2 obtained from a metal halide adduct of S.sub.4N.sub.4.

A method of purifying phosphoric acid solution produced in wet process using nanofiltration. The claimed method contains the following: (a) providing wet phosphoric feed (b) subjecting the said feed to a first nanofilter (c) produce sulfate solids (d) removing the solids (e) subjecting a second nanofilter.

A method of purifying phosphoric acid solution produced in wet process using nanofiltration. The claimed method contains the following: (a) providing wet phosphoric feed (b) subjecting the said feed to a first nanofilter (c) produce sulfate solids (d) removing the solids (e) subjecting a second nanofilter.

Disclosed herein are compositions and methods of mitigating scale in phosphoric acid and ammonium phosphate plants. Scale-mitigating compositions of the invention can be added to phosphoric acid before or during the concentration in the evaporator cycle of a phosphoric acid plant. The compositions retard the formation of scale on surfaces in contact with the phosphoric acid, and thus time between cleaning is extended and plant productivity increased. Further, the scale that forms is softer and more easily cleaned from surfaces, reducing non-operation time of the plant and/or evaporator. Methods of mitigating scale formation in phosphoric acid production and phosphoric acid handling plants are disclosed. In the methods, scales accumulate more slowly and are softer, more tractable, and more easily cleaned from surfaces to which they adhere.

A system for extracting uranium from wet-process phosphoric acid (WPA), includes an ion exchange resin or solvent extractor for separating uranium from WPA to produce a loaded uranium solution stream and a uranium depleted WPA stream. An ion exchange resin is positioned to receive the loaded uranium solution stream and bind uranium species thereto. An anion solution stream is positioned to feed a solution comprising anions onto the ion exchange resin to form a loaded uranium eluant stream. The loaded uranium eluant stream may then be treated to provide a uranium containing product.