| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 564032000 | Ureas (i.e., HNH-CO-HNH, wherein substitution may be made for hydrogen only) | 66 |
| 564033000 | Nitro or nitroso bonded directly to nitrogen | 1 |
| 20090036711 | Process for Producing O-Methyl-N-Nitroisourea - Disclosed is an industrially advantageous process for producing O-methyl-N-nitroisourea. Disclosed is a process for obtaining O-methyl-N-nitroisourea represented by the following chemical formula (1) or a salt thereof in a high yield by performing the nitration of O-methylisourea represented by the following chemical formula (2) or a salt thereof with nitrating agents in the presence of fuming sulfuric acid. | 02-05-2009 |
| 564034000 | Carbazides or semicarbazides (i.e., HNH-NH-CO-HNH, wherein substitution may be made for hydrogen only) | 2 |
| 564035000 | Carbonyl or sulfur attached directly to carbazide or semicarbazide nitrogen by nonionic bonding | 1 |
| 20110118505 | Sulfonyl semicarbazides, semicarbazides and ureas, pharmaceutical compositions thereof, and methods for treating hemorrhagic fever viruses, including infections associated with arenaviruses - Compounds, methods and pharmaceutical compositions for treating viral infections, by administering certain novel sulfonyl semicarbazides, carbonyl semicarbazides, semicarbazides, ureas and related compounds in therapeutically effective amounts are disclosed. Methods for preparing the compounds and methods of using the compounds and pharmaceutical compositions thereof are also disclosed. In particular, the treatment and prophylaxis of viral infections such as caused by hemorrhagic fever viruses is disclosed, i.e., including but not limited to, Arenaviridae (Junin, Machupo, Guanarito, Sabia, Lassa, Tacaribe, Pinchinde, and VSV), Filoviridae (ebola and Marburg viruses), Flaviviridae (yellow fever, omsk hemorrhagic fever and Kyasanur Forest disease viruses), and Bunyaviridae (Rift Valley fever). | 05-19-2011 |
| 564037000 | Acyclic | 1 |
| 20090182171 | Compound having oxadiazole structure and a dehydration-cyclization method for producing the same - A compound having an oxadiazole structure which is obtained by dehydration-cyclization of a compound having a carbohydrazide structure using a chemical agent selected from acids and bases. The dehydration-cyclization of the compound having a carbohydrazide structure can be conducted under mild conditions at low cost. | 07-16-2009 |
| 564038000 | Biurets (i.e., HNH-CO-NH-CO-HNH, wherein substitution may be made for hydrogen only) | 1 |
| 20110065957 | SYNTHESIS OF BIURETS AND ISOCYANATES WITH ALKOXYSILANE FUNCTIONS, FORMULATIONS CONTAINING SAME AND USE THEREOF - The invention relates to a composition and a method of preparing one such composition and an isocyanatoalkoxysilane; the polyisocyanate composition contains at least two different oligomeric compounds comprising at least three units and at most five units selected from aminoalkylsilane units and diamine units and at least one function selected from isocyanate functions and from those derived therefrom, the aforementioned compounds having at least two aminoalkylsilane units and another compound having at least two diamine units; the invention is suitable for coatings. | 03-17-2011 |
| 564044000 | Additional carbonyl bonded directly to urea nitrogen | 1 |
| 564045000 | The additional carbonyl is in a substituent which is acyclic | 1 |
| 564046000 | Carbon to carbon unsaturation in the substituent | 1 |
| 20130090497 | EPOXIDATION OF GLYCEROL AND DERIVATIVES THEREFROM - A method producing a surfactant from glycerol by converting glycerol, in a first step, to glycidol, polymerizing glycidol to an aliphatic alcohol and finally substituting a hydroxyl group with a substitute anion. | 04-11-2013 |
| 564047000 | Benzene ring containing | 6 |
| 20120323040 | PROCESS FOR SYNTHESIS OF AMINO-METHYL TETRALIN DERIVATIVES - Methods for producing a compound of formula k1 or k2 | 12-20-2012 |
| 564048000 | Benzene ring bonded directly to urea nitrogen (i.e., anilides) | 4 |
| 20110098504 | Histone Deacetylase Inhibitors and Methods of Use Thereof - The invention provides novel classes of HDAC inhibitors. Methods of sensitizing a cancer cell to the cytotoxic effects of radiotherapy are also provided as well as methods for treating cancer and methods for treating neurological diseases. Additionally, the invention further provides pharmaceutical compositions comprising an HDAC inhibitor of the invention, and kits comprising a container containing an HDAC inhibitor of the invention. | 04-28-2011 |
| 564050000 | The benzene ring is part of a substituent which contains nitrogen | 3 |
| 20110124916 | THERMAL RESPONSIVE MOLECULE - Provided is a thermal responsive molecule favorable as a thermal responsive low-molecular hydrogelling agent or the like that gels in response to heat. The thermal responsive molecule is characterized in that an amphiphilic side chain obtained by bonding a hydrophilic side chain such as triethylene glycol and a hydrophobic group such as an octyl group is introduced into a C | 05-26-2011 |
| 20140378705 | SEPARATING AGENT AND MANUFACTURING METHOD THEREOF - An embodiment of the present invention is a separating agent wherein a group represented by a chemical formula of: | 12-25-2014 |
| 564051000 | The substituent nitrogen is attached indirectly to the benzene ring by acyclic nonionic bonding | 1 |
| 20110065958 | Low Temperature Curable Epoxy Compositions Containing Urea Curatives - A heat curable epoxy composition comprising the contact product of an epoxy resin, an epoxy curing agent and an accelerator for the epoxy curing agent, the curing agent or the accelerator comprising a urea compound which is the reaction product of an isocyanate and an alkylated polyalkylenepolyamine having one primary or secondary amine and at least two tertiary amines of the general formula: | 03-17-2011 |
| 564056000 | Aralkyl bonded directly to urea nitrogen | 1 |
| 20100160682 | PROCESS FOR SYNTHESIS OF AMINO-METHYL TETRALIN DERIVATIVES - Methods for producing a compound of formula k1 or k2 | 06-24-2010 |
| 564057000 | Alicyclic ring containing | 2 |
| 20090082595 | Process for the production of phosphorous compounds - The invention is directed to a process for the production of certain phosphorous, namely urea, thio-urea and sulphonamide phosphorous compounds. The present invention provides a process for the production of phosphorous compounds which process allows an easy and effective separation of the reaction products from impurities by applying a solid alkaline ion-exchange resin. | 03-26-2009 |
| 20140213820 | BIS-UREA GELATORS FOR CURABLE INK APPLICATIONS - The disclosure provides curable inks including a bis-urea gelator having the structure of Formula I. | 07-31-2014 |
| 564058000 | Additional carbon bonded directly to urea nitrogen | 2 |
| 20120330059 | CRYSTALLIZED DIACETYLENIC INDICATOR COMPOUNDS AND METHODS OF PREPARING THE COMPOUNDS - Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds. | 12-27-2012 |
| 564059000 | The additional carbon is part of a substituent which contains nitrogen | 1 |
| 20120226075 | POLYUREAS AS RHEOLOGY CONTROL AGENTS - The invention relates to polyureas having a weight-average molecular weight ranging from 5,000 to 70,000 g/mol, the preparation thereof, and the use thereof as rheology control agents. The invention further relates to rheology control agents containing polyureas and to the use thereof. The invention moreover relates to formulations containing polyureas. | 09-06-2012 |
| 564063000 | Urea per se or salt thereof | 51 |
| 20080207948 | Method for the Production of Urea from Natural Gas - Disclosed is a method for the production of urea from natural gas, wherein a) natural gas undergoes partial oxidation or autothermal reformation with a gas containing oxygen in a first step and the raw synthesis gas thus arising, consisting essentially of carbon monoxide, carbon dioxide, methane and hydrogen, can be transformed by catalytic conversion of CO and H | 08-28-2008 |
| 20090131718 | CRYSTALLIZED DIACETYLENIC INDICATOR COMPOUNDS AND METHODS OF PREPARING THE COMPOUNDS - Crystallized diacetylenic compounds having certain crystallographic and other characteristics; diacetylenic compounds and mixtures crystallized from diacetylenic solutions; methods of preparing and identifying solvent systems for dissolving diacetylenic compounds; diacetylenic solutions; methods of recrystallizing diacetylenic compounds; crystals of 2,4-hexadiyn-1,6-bis(alkylurea) compounds; and ambient condition indicators and time-temperature condition indicators comprising crystallized diacetylenic compounds. | 05-21-2009 |
| 20090198087 | Method and Device for Providing a Reducing Agent Precursor - A method for providing a reducing agent precursor includes heating a quasi-closed evaporator volume, delimited by a wall and at least partially filled with a solution of a reducing agent precursor, to a reserve temperature of the solution to produce an atmosphere of a vapor including at least one reducing agent precursor at a reserve pressure above ambient pressure. The vapor is extracted on demand by utilizing a pressure difference between the reserve pressure and an ambient pressure. The method and a device provide reducing agent precursors that can especially be used in the selective catalytic reduction of nitrogen oxides. The method and the device allow easy dosing since, due to the pressure gradient between the vapor and an extraction line, no other conveying device is required when the vapor, which contains at least one reducing agent precursor, is dosed to a hydrolysis catalytic converter. | 08-06-2009 |
| 20130053603 | ORAL SMOKELESS TOBACCO PRODUCTS AND ORAL SMOKELESS NON-TOBACCO SNUFF PRODUCTS COMPRISING CARBAMIDE OR CARBAMIDE SALTS - Oral smokeless tobacco products and oral smokeless non-tobacco snuff products include carbamide or carbamide salt(s). The carbamide salt is chosen from the group including carbamide calcium sulphate [4(CH | 02-28-2013 |
| 20130123536 | TUBE-BUNDLE EQUIPMENT FOR PROCESSING CORROSIVE FLUIDS - Tube-bundle equipment for heat exchange operations at high pressures and temperatures, under conditions of high aggressiveness of the process fluids, comprising a titanium lining ( | 05-16-2013 |
| 20130303804 | Process For Preparing A Thixotroping Agent And Use Thereof - The invention provides a process for preparing a thixotropic agent based on a urea derivative, in which the components α) comprising at least one amine and β) comprising at least one isocyanate, are supplied separately to a mixing means and are mixed with one another, the reaction mixture being discharged by spraying or squirting from the mixing means. Further disclosed is the use of the thixotropic agent in a fluid system. The process is especially suitable for preparing adhesives and sealants. | 11-14-2013 |
| 20140005436 | Method for Treating Offgases from a Melamine Plant | 01-02-2014 |
| 20140357893 | RECOVERY FROM ROCK STRUCTURES AND CHEMICAL PRODUCTION USING HIGH ENTHALPY COLLIDING AND REVERBERATING SHOCK PRESSURE WAVES - An example system includes a combustion chamber including at least one inlet and at least one outlet, and at least one reflective surface to direct shock waves in a pattern that meets at a midline nodal point. The example system also includes an ignition source to generate high enthalpy colliding and reverberating shock pressure waves and detonation gasses for dynamic pressurization. An example method for using high enthalpy colliding and/or reverberating shock pressure waves for chemical and material processing. The example method includes providing a combustion chamber including at least one inlet and at least one outlet, and at least one reflective surface to direct shock waves in a pattern that meets at a midline nodal point. The example method also includes colliding reflected or opposing combustion-induced or detonation-induced wave fronts within the combustion chamber. | 12-04-2014 |
| 20150133689 | UREA GRANULATION PROCESS WITH SCRUBBING SYSTEM - Disclosed is a method for producing granular urea and reducing ammonia emissions in a gaseous waste stream of the urea granulation process. The method includes the steps of granulating urea and generating a gaseous waste stream from the granulation of the urea, first washing the waste stream in a first scrubber dust stage to remove dust form the gaseous waste stream, and then reacting the gaseous waste stream with formaldehyde in a formaldehyde stage to generate a hexamethylenetetramine and urea-formaldehyde liquid stream, and an ammonia-reduced off-gas stream. | 05-14-2015 |
| 564065000 | Preparing directly from ammonia and carbonmonoxide or carbon oxysulfide (e.g., from ammonia and COS, etc.) | 1 |
| 20160251229 | AMMONIA SYNTHESIS FOR FERTILIZER PRODUCTION | 09-01-2016 |
| 564066000 | Preparing directly from ammonium carbamate (i.e., from HNH-COO-HHNHH) | 5 |
| 20090216045 | APPARATUS AND METHODS FOR UREA PRODUCTION - Apparatus and methods for producing urea are provided. In one or more embodiments, an apparatus for producing urea can include a first zone, which can include a first flow channel in fluid communication with a first tube disposed about a first end of a plurality of trays, a second flow channel in fluid communication with a second tube disposed about the first end of the trays and a second end of the trays, and a third flow channel in fluid communication with a third tube disposed about the first and second ends of the trays. The apparatus can include a second zone, which can include a fixed bed comprising one or more inert packing materials disposed therein to provide additional surface area. The apparatus can include a third zone, which can include a plurality of tubes disposed therein. The second zone can be disposed between the first and third zones. | 08-27-2009 |
| 20100016635 | SYSTEMS AND METHODS FOR INTEGRATED AMMONIA-UREA PROCESS - Systems and methods for producing urea are provided. A method for producing urea can include exchanging heat from a syngas comprising hydrogen and carbon dioxide to a urea solution comprising urea and ammonium carbamate. The heat transferred can be sufficient to decompose at least a portion of the ammonium carbamate. In one or more embodiments, the syngas can be reacted with liquid ammonia to provide a carbon dioxide lean syngas and an ammonium carbamate solution. The ammonium carbamate solution can be heated to a temperature of about 180° C. or more. At least a portion of the ammonium carbamate in the heated ammonium carbamate solution can be dehydrated to provide the urea solution. | 01-21-2010 |
| 20100076222 | Systems and Methods for Integrated Ammonia-Urea Process - Methods for producing urea are provided. A method for producing urea can include exchanging heat from a syngas comprising hydrogen and carbon dioxide to a urea solution comprising urea and ammonium carbamate. The heat transferred can be sufficient to decompose at least a portion of the ammonium carbamate. In one or more embodiments, the syngas can be reacted with liquid ammonia to provide a carbon dioxide lean syngas and an ammonium carbamate solution. The ammonium carbamate solution can be heated to a temperature of about 180 C or more. At least a portion of the ammonium carbamate in the heated ammonium carbamate solution can be dehydrated to provide the urea solution. | 03-25-2010 |
| 20150322000 | UREA SYNTHESIS PROCESS AND PLANT - Disclosed is a urea plant comprising an additional reactor. With reference to the regular components of a urea plant, including a recovery section and a high pressure carbamate condenser, the additional reactor is positioned between the recovery section and the high pressure carbamate condenser. The invention also relates to a process for the synthesis of urea, comprising an additional reaction step converting, at an earlier stage than conventional, recovered carbamate into urea. | 11-12-2015 |
| 20160175795 | GAS DIFFUSION SYSTEM AND METHOD FOR INTRODUCING A GAS STREAM IN AN APPARATUS, IN PARTICULAR A PASSIVATING GAS STREAM IN A UREA PLANT | 06-23-2016 |
| 564067000 | Preparing directly from ammonia and carbon dioxide | 35 |
| 20080242890 | Method for Modernizing a Urea Production Plant - A method for modernizing a urea production plant including a urea synthesis reactor, a stripping unit and at least one condensation unit. The method includes providing: means in the condensation unit for substantially condensing at least a portion of a flow comprising ammonia and carbon dioxide in vapor phase leaving the stripping unit; a second stripping unit; means for feeding a first portion of a reaction mixture flow comprising urea, carbamate and free ammonia in aqueous solution leaving the reactor to the first stripping unit; means for feeding a second portion of the reaction mixture flow leaving the reactor to the second stripping unit; and means for feeding at least a portion of a flow comprising ammonia and carbon dioxide in vapor phase leaving the second stripping unit directly to the synthesis reactor. A de-bottlenecking of the high-pressure section downstream of the synthesis reactor may be achieved, improving production capacity. | 10-02-2008 |
| 20080300422 | Process For The Preparation Of Urea - The invention relates to a process for the preparation of urea from ammonia and carbon dioxide in a urea plant that contains a high-pressure synthesis section and one or more recovery section(s) at a lower pressure, the high-pressure synthesis section comprising a reactor, a stripper and a condenser, with gases leaving the high-pressure synthesis section being condensed in a medium-pressure condenser at 0.5-12 MPa to which also a carbamate stream from one of the recovery sections is supplied, after which at least a part of the formed condensate is supplied to the high-pressure condenser. | 12-04-2008 |
| 20090036712 | APPARATUS FOR SYNTHESIZING UREA - It is intended to enable more smooth operation in an apparatus for synthesizing urea by circumventing the downward flow of a urea synthesis solution which is a gas-liquid two-phase flow and stabilizing the flow of the urea synthesis solution still remaining the gas-liquid two-phase flow and to reduce energy loss by giving smaller flow resistance. The present invention provides an apparatus for synthesizing urea including: a synthesis reactor for reacting NH | 02-05-2009 |
| 20090062566 | APPARATUS FOR SYNTHESIZING UREA AND METHOD FOR REVAMPING THE SAME - It is intended to enable an apparatus for synthesizing urea and a method for revamping the same to place a heavy condenser at a relatively low position and to circumvent problems associated with letting a process fluid flow within a tube in the condenser. The present invention provides an apparatus for synthesizing urea including: a synthesis reactor for reacting NH | 03-05-2009 |
| 20100168473 | PROCESS FOR THE PREPARATION OF UREA - Process for the preparation of urea from ammonia and carbon dioxide in a urea production process comprising, in a high-pressure synthesis section: a. a reactor, wherein ammonia and carbon dioxide react to form a urea-comprising synthesis solution; b. a stripper, wherein the urea-comprising synthesis solution is heated and stripped, optionally in counter-current with a stripping agent; c. a submerged condenser, wherein the gas leaving the top of the stripper is, at least partially, condensed to form a condensate solution and d. an ejector, in the line connecting the submerged condenser and the reactor, supporting the transport of the condensate solution from the submerged condenser to the reactor, wherein a gas stream leaving the top of the submerged condenser is controlled by one or more controlling elements. | 07-01-2010 |
| 20100210874 | Process and Plant for Urea Production - A process for producing urea is disclosed, wherein liquid ammonia and carbon dioxide are reacted in a high-pressure synthesis section ( | 08-19-2010 |
| 20110118506 | PROCESS FOR THE PRODUCTION OF UREA FROM AMMONIA AND CARBON DIOXIDE - Process for the production of urea from ammonia and carbon dioxide in a urea plant containing a high-pressure synthesis section comprising at least one reactor section, a stripper and a condenser wherein all the high-pressure equipment is placed in a low position, wherein the height of the high-pressure section is less than 35 m from ground level and at least one of the reactor sections comprises means for the separate distribution of ammonia in the bottom of the reactor section. | 05-19-2011 |
| 20110144389 | Modularized System and Method for Urea Production Using a Bio-Mass Feedstock - A modular system and method for producing urea from bio-mass includes cleaning a bio-mass feedstock to remove substantially all non-organic matter; blending the cleaned bio-mass to obtain a substantially homogeneous blend; pelletizing the blended bio-mass; and gasifying the pellets in a gasifier. The bio-mass feedstock may include bio-mass materials having different processing characteristics. The gasifying step preferably includes pulverizing the pellets to a fine particle size, injecting an organic oil into the input biomass mist when needed, and controlling the feed rate to maintain a substantially constant burn temperature. The resultant syngas stream is cleaned and compressed to a high pressure of about 6,000 to 7,000 psi. The resultant ammonia stream is processed in a bypass recycling loop system at 30% conversion rate at a high pressure of about 6,000 to 7,000 psi. | 06-16-2011 |
| 20110160486 | PROCESS FOR THE PRODUCTION OF UREA FROM AMMONIA AND CARBON DIOXIDE - Process for the production of urea from ammonia and carbon dioxide in a urea plant containing a high-pressure synthesis section comprising two reactor sections, a stripper and a condenser, and a recovery section, wherein in the first reactor section a first synthesis solution is formed that is fed to the second reactor section; fresh carbon dioxide is fed to the second reactor section and in the second reactor section a second synthesis solution is formed that is fed to the stripper, wherein the second synthesis solution is stripped with the use of carbon dioxide as stripping gas and the mixed gas stream obtained in the stripper is sent to the condenser together with fresh ammonia and a carbamate stream, whereafter the condensate that is formed in the condenser is fed to the first reactor section and the urea stream that is obtained in the stripper is further purified in the recovery section, wherein the flow of the first synthesis solution from the first reactor section to the second reactor section, the flow of the second synthesis solution from the second reactor section to the stripper, the flow of the mixed gas stream from the stripper to the condenser and of the condensate from the condenser to the first reactor section is a gravity flow. | 06-30-2011 |
| 20110306791 | IMPROVEMENT TO THE HIGH-PRESSURE LOOP IN A PROCESS FOR SYNTHESIS OF UREA - A process and a related plant layout for producing urea are disclosed, wherein the high-pressure loop ( | 12-15-2011 |
| 20120136172 | Modularized System and Method for Urea Production Using Stranded Natural Gas - A modular system and method for producing urea from stranded natural gas includes removal of foreign particulate matter to obtain a substantially homogeneous gas. The gas is processed by controlling the quality of the stranded natural gas to maintain a substantially homogenous mixture The resultant gas stream is further cleaned and compressed to a high pressure of about 3,000 psi. The resultant ammonia stream is processed in a bypass recycling loop system at 30% conversion rate at a high pressure of about 6,000 to 7,000 psi. The equipment associated with each of the process steps may be skid mounted for portability and/or contained within the footprint of a standard 48-foot flatbed trailer. | 05-31-2012 |
| 20120302789 | UREA STRIPPING PROCESS FOR THE PRODUCTION OF UREA - The invention relates to a process for producing urea wherein an aqueous urea solution, leaving a urea reaction zone is fed to a stripper, where a part of the non-converted ammonia and carbon dioxide is separated from the aqueous urea solution, which solution leaves the stripper to a first recovery section of one or more serial recovery sections and is subsequently fed to one or more urea concentration sections, wherein the urea solution leaving the stripper is subjected to an adiabatic expansion, thus creating a vapor and a liquid, which are separated before the liquid enters a first recovery section and the vapor is condensed. The invention further relates to a urea plant comprising a stripper and a first recovery section, wherein an adiabatic expansion valve and a liquid/gas separator is provided between the stripper and the first recovery section. | 11-29-2012 |
| 20120330060 | REMOVAL OF AMMONIA IN UREA FINISHING - Disclosed is a method for the removal of ammonia from the off-gas of a finishing section of a urea production plant. The method comprises contacting the off-gas with a solid adsorbent capable of physically adsorbing ammonia, particularly activated carbon or zeolite. Thereupon the solid adsorbent having ammonia adsorbed thereon is separated from the gas and regenerated by dissolving ammonia in an extraction liquid, preferably water. After separating the water from the solid adsorbent, the latter is re-used in the process. | 12-27-2012 |
| 20140046094 | ZERO EMISSION UREA PROCESS AND PLANT - Disclosed is a method for the production of urea allowing a substantial reduction, even down to zero, of the continuous emission of ammonia conventionally resulting from such a process. According to a preferred embodiment of the invention, the urea-forming reaction from carbon dioxide and ammonia is conducted in a synthesis section that does not require passivation by oxygen. As a result of the absence of oxygen, a hydrogen-rich gas stream results from the synthesis section, that can be used as a fuel in an incinerator. In the incinerator, ammonia-comprising gas streams from the urea production process are combusted. | 02-13-2014 |
| 20140171686 | UREA REACTOR TRAY, REACTOR, AND PRODUCTION PROCESS - A urea reactor tray having a base plate; and a number or quantity of hollow cup-shaped members, which project vertically from the base plate along respective substantially parallel axes perpendicular to the base plate, and have respective substantially concave inner cavities communicating with respective openings formed in the base plate; the tray having a number or quantity of first cup-shaped members, each of which extends axially between an open top end having the opening, and a closed bottom end, and has a lateral wall with through holes substantially crosswise to the axis, and a bottom wall which closes the closed bottom end and has no holes. | 06-19-2014 |
| 20140206902 | UREA PRODUCTION PROCESS CHARACTERIZED BY SHORT UREA MELT TRANSPORTATION TIME BETWEEN LAST CONCENTRATOR AND PRILLING TOWER - The invention relates to a method for urea production and to a urea production plant wherein ammonia emission in the final step of forming urea prills is reduced. In the method, the concentration of a urea solution is performed in at least three consecutive concentration steps and the residence time of urea melt leaving a last concentrator to the prilling tower is minimised. This can be achieved by placing the last concentrator in adjacency with a urea melt inlet of the prilling tower, such as above the prilling tower. In this way, the ammonia emission in the prilling tower can be reduced by as much as 50% compared to the conventional urea production plants. The invention further relates to a method for reducing ammonia emission in the prilling tower of an existing urea production plant. | 07-24-2014 |
| 20140275626 | OPERATION METHOD OF UREA PRODUCTION PLANT INCLUDING MULTIPLE SYSTEMS - An operation method of a urea production plant including multiple systems that can prevent a considerable decrease in urea production even when an ammonia synthesis facility is shut down. At a time of producing urea from CO | 09-18-2014 |
| 20150133690 | UREA PRODUCTION PLANT - Disclosed is a plant for the production of urea. The plant comprises conventional sections for synthesis and recovery, for evaporation and condensation, for urea finishing, and for dust scrubbing. According to the invention, an additional evaporation and condensation loop is introduced from and to the dust scrubbing section. This loop results in a more favorable energy consumption of the plant. | 05-14-2015 |
| 20160096801 | Modularized System and Method for Urea Production Using Stranded Natural Gas - A modular system and method for producing urea from stranded natural gas includes removal of foreign particulate matter to obtain a substantially homogeneous gas. The gas is processed by controlling the quality of the stranded natural gas to maintain a substantially homogenous mixture The resultant gas stream is further cleaned and compressed to a high pressure of about 3,000 psi. The resultant ammonia stream is processed in a bypass recycling loop system at 30% conversion rate at a high pressure of about 6,000 to 7,000 psi. The equipment associated with each of the process steps may be skid mounted for portability and/or contained within the footprint of a standard 48-foot flatbed trailer. | 04-07-2016 |
| 564068000 | With corrosion inhibiting of reactor | 1 |
| 20160075642 | UREA SYNTHESIS METHOD - There is provided a urea synthesis method having excellent reliability and productivity with the amount of oxygen used as a corrosion-resistant agent minimized without using special duplex stainless steel. In a urea synthesis apparatus having a synthesis tower, a stripper, and a condenser, general-purpose austenitic-ferritic duplex stainless steel with Cr content: 21 to 26 wt %, Ni content: 4.5 to 7.5 wt %, Mo content: 2.5 to 3.5 wt %, N content: 0.08 to 0.30 wt %, C content: 0.03 wt % or less, Si content: 1.0 wt % or less, Mn content: 2.0 wt % or less, P content: 0.04 wt % or less, and S content: 0.03 wt % is used as a urea synthesis apparatus material in at least some of parts where the urea synthesis apparatus comes into contact with a fluid having corrosiveness, and oxygen feed concentration with respect to carbon dioxide is 100 to 2,000 ppm. | 03-17-2016 |
| 564069000 | With ammonia synthesis | 6 |
| 20100099914 | METHOD FOR PURIFYING FLUE GASES FROM COMBUSTION PLANTS AND THEN PRODUCING UREA - A method and apparatus is provided for cleaning flue gases from combustion plants. The method includes removing dust and removing nitrogen from flue gases, bringing flue gases into contact with an aqueous ammonia solution in the presence of an oxidizing agent whereby a reaction solution forms which contains at least ammonium carbonate, heating the reaction solution such that ammonium carbonate decomposes and carbon dioxide and ammonia transfer into the gas atmosphere, and reacting the gaseous carbon dioxide and the gaseous ammonia to form urea. The apparatus includes a device for removing nitrogen and removing dust from the flue gases, a washing device downstream of the device for removing nitrogen and removing dust, a stripper downstream of the washing device, and a urea installation downstream of the stripper. | 04-22-2010 |
| 20130116472 | PROCESS FOR PREPARING UREA - A method of producing urea includes reacting SiO | 05-09-2013 |
| 20140018575 | Process and Plant for Ammonia-Urea Production - A process for ammonia -urea production where: liquid ammonia produced in an ammonia section is fed to a urea section directly at the ammonia synthesis pressure, and where the liquid ammonia is purified at high pressure with the steps of: cooling the liquid ammonia ( | 01-16-2014 |
| 20140364647 | PROCESS FOR PRODUCING AMMONIA AND UREA - Disclosed is a process for the production of ammonia comprising a step wherein synthesis gas is formed in two different ways, viz. by catalytic partial oxidation ( | 12-11-2014 |
| 20150031916 | METHOD OF MANUFACTURING UREA FROM REFUSE, PREFERABLY DOMESTIC WASTE, OF ANY COMPOSITION - The invention relates to a method of manufacturing urea as a nitrogen-rich synthetic fertilizer from refuse of any composition, preferably from domestic waste. The organic waste components are first turned into gas in a high-temperature reactor with oxygen (O | 01-29-2015 |
| 20150368191 | METHOD OF FORMING UREA BY INTEGRATION OF AN AMMONIA PRODUCTION PROCESS IN A UREA PRODUCTION PROCESS AND A SYSTEM THEREFOR - A method of forming urea by integration of an ammonia production process with that of a urea production process, as well as a system for the method is disclosed. Also, an alternative method of forming urea by integration of a part of an ammonia production process with that of a urea production process, as well as a system for the alternative method. | 12-24-2015 |
| 564070000 | With decomposition of by-product ammonium carbamate (i.e., decomposition of HNH-COO-HHNHH) | 9 |
| 20090124830 | Process for Urea Production and Related Plant - A process for urea production from ammonia and carbon dioxide, in which part of the aqueous solution comprising urea, ammonium carbamate and ammonia obtained in a urea synthesis section is subjected to dissociation in a treatment section operating at a predetermined medium pressure for the recovery of the ammonium carbamate and of the ammonia contained in it, comprises the step of subjecting the urea aqueous solution resulting from the aforementioned dissociation step to decomposition in a low pressure urea recovery section. | 05-14-2009 |
| 20100217041 | ENHANCED PROCESS FOR THE SYNTHESIS OF UREA - An enhanced process is described for the synthesis of urea from ammonia and carbon dioxide, at a high pressure and temperature, with the formation of ammonium carbamate as intermediate, which includes a high pressure synthesis section, comprising at least one separation step by decomposition-stripping with ammonia of the non-converted ammonium carbamate, carried out in a vertical apparatus, commonly called stripper, characterized in that said step also comprises a feeding, in the lower part of said stripper, of a stream of CO | 08-26-2010 |
| 20150025273 | PROCESS FOR THE SYNTHESIS OF UREA COMPRISING A PASSIVATION STREAM AT THE STRIPPER BOTTOM - A process for the direct synthesis of urea from ammonia and carbon dioxide with increased corrosion resistance, comprising, in the high-pressure synthesis section, a reaction step in a vertical reactor fed with at least one stream of fresh carbon dioxide containing a passivating agent and a decomposition-stripping step of the non-converted reagents, wherein the gas-liquid mixture collected at the head of the reactor is separated into a gaseous stream and a liquid stream fed to the tail and head of the stripper, respectively. | 01-22-2015 |
| 20150119603 | METHOD AND APPARATUS FOR THE PRODUCTION OF UREA FROM AMMONIA AND CARBON DIOXIDE - Method for the production of urea from ammonia and carbon dioxide in a urea plant containing a high-pressure synthesis section with a horizontal pool condenser, wherein the method comprises exchanging heat from a high pressure process medium received in a shell section of the pool condenser to a medium pressure urea containing solution received in a first heat exchanging section provided in the pool condenser to at least decompose ammonium carbamate into NH | 04-30-2015 |
| 20160082408 | USE OF DUPLEX STAINLESS STEEL IN AN AMMONIA-STRIPPING OF UREA PLANTS - In an ammonia stripping or self-stripping plant for the synthesis of urea, it is disclosed that a shell-and-tube stripper has a bundle of tubes made of a duplex stainless steel 29Cr-6.5Ni-2Mo—N according to UNS S32906 or 27Cr-7.6Ni-1 Mo-2.3W—N according to UNS S32808. A revamping of urea plants is also disclosed, including the revamping of ammonia stripping plants, self-stripping plants and conventional total recycle plants, wherein said duplex stainless steel is used for the tubes of the stripper. | 03-24-2016 |
| 564071000 | Utilizing indirect heat exchange | 2 |
| 20100063321 | Process for Urea Production and Related Plant - A process for urea production from ammonia and carbon dioxide, in which part of the aqueous solution comprising urea, ammonium carbamate and ammonia obtained in a urea synthesis section is subjected to dissociation in a treatment section operating at a predetermined medium pressure for the recovery of the ammonium carbamate and of the ammonia contained in it, comprises the steps of subjecting the urea aqueous solution resulting from the aforementioned dissociation step to decomposition in a low pressure urea recovery section and of using at least a part of the condensed steam, obtained by indirect thermal exchange with a second part of said aqueous solution comprising urea, ammonium carbmate and ammonia in a high-pressure stripping unit, as a heating fluid for the dissociation of the first part of the aqueous solution comprising urea, ammonium carbmate and ammonia in the medium-pressure treatment section. | 03-11-2010 |
| 20140081046 | HIGH-YIELD PROCESS FOR THE SYNTHESIS OF UREA - A process for the direct synthesis of urea from ammonia and carbon dioxide at high pressures and temperatures, with the formation of ammonium carbamate as intermediate, comprising a decomposition step of the ammonium carbamate and stripping of the gases formed, operating substantially at the same pressure as the synthesis step, wherein the recycled liquid streams are fed, at least partially, to the same decomposition and stripping step after being preheated by heat exchange with a stream included in the high-pressure synthesis cycle. | 03-20-2014 |
| 564072000 | In plural stages | 2 |
| 20090292140 | Method for the Modernization of a Urea Production Plant - A method for revamping a conventional self-stripping urea plant is disclosed, where a minor portion ( | 11-26-2009 |
| 20140330040 | PROCESS FOR SYNTHESIS OF UREA AND A RELATED ARRANGEMENT FOR A REACTION SECTION OF A UREA PLANT - A process for synthesis of urea and a related reaction section of a urea plant, where: ammonia and carbon dioxide are reacted in a liquid phase in a first reaction zone (S | 11-06-2014 |
| 564073000 | Purification or recovery | 1 |
| 20120296120 | Falling-Film Stripper for Carbamate Decomposition - A stripper (S | 11-22-2012 |
