Abstract: A process for the production of ammonia and urea in an ammonia-urea integrated plant comprising an ammonia section and a tied-in urea section, wherein a hydrocarbon is reformed to produce ammonia make-up synthesis gas; said make-up gas is purified by shift conversion and removal of carbon dioxide; carbon dioxide is removed from the make-up gas by a first and a second CO2 removal sections; the first section removes CO2 by absorption with a suitable medium, and the second section removes CO2 by washing with a carbamate solution taken from the urea section; the make-up gas is reacted to produce ammonia; the CO2 removed from the make-up gas and at least part of the ammonia are used to produce urea.

Abstract: A method and system for measuring a liquid level in a pressure vessel, the method comprising: transmitting an electromagnetic signal through a wave guide in the form of an elongate solid rod (5) with bottom end immersed in the liquid and detecting a signal generated by the reflection on the surface of the liquid.

Abstract: A process and system for removing ammonia from ammonia-containing purge gas of a urea plant, the process comprising: contacting said ammonia-containing purge gas with carbon dioxide at a low temperature, reaction of ammonia to form crystals of ammonium salts in a multiphase stream, and removal of the solid ammonium salts from the multiphase stream.

Abstract: A shell-and-tube stripper for carbamate decomposition and ammonia recovery from a urea solution comprising a bundle of heated tubes, said tubes being fed with said urea solution and carbon dioxide as stripping medium, the urea solutions forming a liquid falling film on the internal surface of the tubes and the carbon dioxide forming a counter-current gaseous flow; said tubes comprise an external layer made of super austenitic or super duplex stainless steel and an internal layer made of zirconium, said internal layer reaching temperatures higher than 220° C.

Abstract: A process for making a combined fertilizer comprising a first nitrogen-based fertilizer, such as urea or ammonium nitrate, and one or more further components chosen among: nitrogen-based fertilizers, being different from the first nitrogen-based fertilizer and nutrients, wherein the combined fertilizer is made by a process of granulation in a fluid bed, the fluid bed being preferably in a vortex condition.

Abstract: Integrated process for the production of urea and urea-ammonium nitrate, comprising: reacting ammonia and carbon dioxide to form a reaction mixture (4) containing urea and unconverted materials, and also comprising the recovery of unconverted materials in a first recovery stage at a first pressure and in a second recovery stage at a second pressure, wherein ammonia-containing offgas (19) released by said second recovery stage are condensed at said second pressure, and said condensed offgas (20) are recycled to said first recovery stage.

Abstract: A process for the production of ammonia and urea in an ammonia-urea integrated plant comprising an ammonia section and a tied-in urea section, wherein a hydrocarbon is reformed to produce ammonia make-up synthesis gas; said make-up gas is purified by shift conversion and removal of carbon dioxide; carbon dioxide is removed from the make-up gas by a first and a second CO2 removal sections;the first section removes CO2 by absorption with a suitable medium, and the second section removes CO2 by washing with a carbamate solution taken from the urea section; the make-up gas is reacted to produce ammonia; the CO2 removed from the make-up gas and at least part of the ammonia are used to produce urea.

Abstract: A process and system for removing ammonia from ammonia-containing purge gas of a urea plant, the process comprising: contacting said ammonia-containing purge gas with carbon dioxide at a low temperature, reaction of ammonia to form crystals of ammonium salts in a multiphase stream, and removal of the solid ammonium salts from the multiphase stream.

Abstract: A combined reactor and condenser for the synthesis of urea from ammonia and carbon dioxide, including a condenser section coupled to a reaction section, comprising inputs directed to said condenser section for a gaseous stream comprising ammonia and carbon dioxide and for a solution containing ammonium carbamate and liquid ammonia, and wherein the effluent of the condenser section is sent to the reaction section; the reaction section comprises a plurality of compartments and a plurality of mixers, at least one inside each of said compartments.

Abstract: Integrated process for the production of urea and urea-ammonium nitrate, comprising: reacting ammonia and carbon dioxide to form a reaction mixture (4) containing urea and unconverted materials, and also comprising the recovery of unconverted materials in a first recovery stage at a first pressure and in a second recovery stage at a second pressure, wherein ammonia-containing offgas (19) released by said second recovery stage are condensed at said second pressure, and said condensed offgas (20) are recycled to said first recovery stage.

Abstract: The invention discloses the use of Raman spectroscopy to analyze one or more process streams (5) of a urea synthesis production plant, where urea is synthesised from ammonia and carbon dioxide at high pressure (100-300 bar) and high temperature (50-250° C.). The radiation generated by the Raman scattering is analyzed to determine the concentration of components such as urea, ammonia and carbon dioxide in the process streams (5). A logic system implemented in a plant control unit (1) generates signals to target plant actuators to optimize the operation.

Abstract: A shell-and-tube stripper for carbamate decomposition and ammonia recovery from a urea solution comprising a bundle of heated tubes, said tubes being fed with said urea solution and carbon dioxide as stripping medium, the urea solutions forming a liquid falling film on the internal surface of the tubes and the carbon dioxide forming a counter-current gaseous flow; said tubes comprise an external layer made of super austenitic or super duplex stainless steel and an internal layer made of zirconium, said internal layer reaching temperatures higher than 220° C.

Abstract: A combined reactor and condenser for the synthesis of urea from ammonia and carbon dioxide, including a condenser section coupled to a reaction section, comprising inputs directed to said condenser section for a gaseous stream comprising ammonia and carbon dioxide and for a solution containing ammonium carbamate and liquid ammonia, and wherein the effluent of the condenser section is sent to the reaction section; the reaction section comprises a plurality of compartments and a plurality of mixers, at least one inside each of said compartments.

Abstract: A process for making a combined fertilizer comprising a first nitrogen-based fertilizer, such as urea or ammonium nitrate, and one or more further components chosen among: nitrogen-based fertilizers, being different from the first nitrogen-based fertilizer and nutrients, wherein the combined fertilizer is made by a process of granulation in a fluid bed, the fluid bed being preferably in a vortex condition.

Abstract: The invention discloses the use of Raman spectroscopy to analyze one or more process streams (5) of a urea synthesis production plant, where urea is synthesised from ammonia and carbon dioxide at high pressure (100-300 bar) and high temperature (50-250° C.). The radiation generated by the Raman scattering is analyzed to determine the concentration of components such as urea, ammonia and carbon dioxide in the process streams (5). A logic system implemented in a plant control unit (1) generates signals to target plant actuators to optimize the operation.