专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明专利

JPH09255650A PREVENTION OF ADHESION IN INTERIOR OF SEPARATOR 失效
公开(公告)号：JPH09255650A
公开(公告)日：1997-09-30
申请号：JP7431196
申请日：1996-03-28
申请人： TOYO ENGINEERING CORP
发明人： MORIKAWA HARUYUKI , YAMAMOTO YOSHIO , YANAGISAWA YUZURU
IPC分类号： B01D1/30 , B01J19/00 , C07C273/16 , C07C275/02
摘要： PROBLEM TO BE SOLVED: To provide a method for preventing adhesion of urea in the interior of a separator in a concentrating process having an evaporator and the separator for concentrating an aqueous solution of urea under reduced pressure in a urea process and a urea process of large particle. SOLUTION: In a separator 1 in a concentrating process having an evaporator 7 and the separator 1, steam or an aqueous solution of urea or both are sprayed from holes bored through plural pipings of an inner wall upper than a raw material feed opening 8, a horizontal part 5 of a shielding part and a vertical part 50 of the shielding plate so as to wet the inner wall upper than the raw material feed opening 8 and shielding plate.

2. 发明专利

JPS55145659A CONCENTRATION OF AQUEOUS SOLUTION OF UREA 失效
公开(公告)号：JPS55145659A
公开(公告)日：1980-11-13
申请号：JP5251979
申请日：1979-05-01
申请人： MITSUI TOATSU CHEMICALS , TOYO ENGINEERING CORP
发明人： NOBUE MICHIO , FUKUI AKITO , YAMAMOTO YOSHIO
IPC分类号： C07C67/00 , C07C239/00 , C07C273/16
摘要： PURPOSE:To concentrate an aqueous solution of urea, economically, suppressing the hydrolysis of urea and formation of biuret, by concentrating the urea solution in vacuum, and then concentrating under hot gas stream. CONSTITUTION:An aqueous solution of urea is introduced from a purifying system 1 into a vacuum evaporator 3, and concentrated to a concentration of 95-99wt% under 40-300mm.Hg, pref. 60-120mm.Hg abs. The steam evaporated in the vacuum evaporator 3 in condensed in a condenser 8. The concentrated urea solution is fed to a hot gas stream dryer 13 through lines 6 and 12, and made to contact countercurrently with hot gas stream exhausted from the line 14 to the line 16. The urea dried to the concentration of >=99.5wt% is obtained from the line 15. The drying in the hot gas stream dryer is carried out under the atmospheric pressure, at 135- 200 deg.C, pref. 150-170 deg.C. The process has the combined advantages of the vacuum concentration and the hot gas stream drying.

3. 发明专利

JPS57200352A PREPARATION OF UREA 失效
公开(公告)号：JPS57200352A
公开(公告)日：1982-12-08
申请号：JP8256981
申请日：1981-06-01
申请人： TOYO ENGINEERING CORP , MITSUI TOATSU CHEMICALS
发明人： YAMAMOTO YOSHIO , KUWATA TOSHIKAZU , WATANABE HIROSHI , FUJII HIDETSUGU
IPC分类号： C07C273/04 , C07C67/00 , C07C239/00
摘要： PURPOSE:To prepare the economically, by heating the urea synthesis liquid obtained by the reaction of NH3 and CO2 to decompose the unconverted material into NH3 and CO2, and recycling the unconverted material to the urea synthesis stage using the transfer of heat in the system and without using external energy. CONSTITUTION:The urea synthesis liquid (composed of urea, water, unconverted ammonium carbamate, etc.) is supplied from the urea synthesis tube 1 through the pipe 11 to the high pressure decomposition reactor 2 maintained to the pressure equal to that of urea synthesis. The liquid is heated in the decomposition reactor 2 at 170-220 deg.C to decompose at least a part of the unconverted material to the gaseous mixture of NH3 and CO2, which is transferred through the pipe 16 to the condenser 3 to cool and separate the gas. The separated gas is recycled to the synthesis tube 1 through the pipe 20. The mixed gas is condensed and absorbed at the ejector part of the condenser 3 using a cooling medium as the driving medium. The pressure of the aqueous solution of urea is released by the reducing valve 14, and the solution is sent to the low-pressure decomposition stage and the finishing stage through the pipe 15 to obtain the urea product.

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式