Snamprogetti process

The Snamprogetti process utilizes a tubular isothermal reactor (tubes filled with catalyst) for the first reactor with cooling water on the shell side to control temperature. The Huls process uses either an adiabatic or isothermal reactor for the first reactor. 

The second reaction represents the decomposition of the carbamate. The reaction conditions are 200°C and 30 atmospheres. Decomposition in presence of excess ammonia limits corrosion problems and inhibits the decomposition of the carbamate to ammonia and carbon dioxide. The urea solution leaving the carbamate decomposer is expanded by heating at low pressures and ammonia recycled. The resultant solution is further concentrated to a melt, which is then prilled by passing it through special sprays in an air stream. Figure 5-3 shows the Snamprogetti process for urea production. ... 

Figure 5-3. The Snamprogetti process for producing urea (1) reactor, (2,3,4) carbonate decomposers, (5,6) crystallizing and prilling.

The Snamprogetti process is based on using ammonia to strip CO2 and NH3 out of the urea reactor effluent. One of the impurities that affects the performance of urea as a fertilizer is biuret. To avoid a yield loss and minimize product contamination, it is important to minimize biuret formation. The con-... 

Mitsui Toatsu Chemicals and Snamprogetti offer plants with capacities of up to 1800 metric tons/day. A variety of modifications are available with these processes, the latest of which incorporate energy-saving developments. The Snamprogetti process is shown in Fig. 28.18. ... 

At this time over 95% of all new urea plants are Hcensed by Snamprogetti, Stamicarbon, or Toyo Engineering. SNAM utilizes thermal stripping while STAC (Stamicarbon) and Toyo use CO2 stripping. Only these three processes are, therefore, covered in detail. Process flow sheets are included for others at the end of this section. 

The Snamprogetti fluidized-bed process uses a chromium catalyst in equipment that is similar to a refinery catalytic cracker (1960s cat cracker technology). The dehydrogenation reaction takes place in one vessel with active catalyst deactivated catalyst flows to a second vessel, which is used for regeneration. This process has been commercialized in Russia for over 25 years in the production of butenes, isobutylene, and isopentenes. 

A three-step process developed hy Snamprogetti is based on the reaction of acetylene and acetone in liquid ammonia in the presence of an alkali metal hydroxide. The product, methylhutynol, is then hydrogenated to methylhutenol followed hy dehydration at 250-300°C over an acidic heterogeneous catalyst. 

Commercial VR HCK processes include LC Fining from Chevron-Lummus Global H-Oil from Axens/IFP Canmet from Petro-Canada HC3 from Hydrocarbon Technologies, Inc. Hycycle Unicracking from UOP VCC from Veba Oil HDH from Intevep SA - IFP U-Can from SCN-Lavalin and ENI Slurry Technology (EST) from Snamprogetti SpA and EniTecnologie. 

MAS [Methanolo alcooli superiori] A process for making mixtures of methanol with higher alcohols, for use as gasoline extenders, developed by a consortium of Snamprogetti, Haldor Topsoe, and Anic. Piloted in a demonstration plant in Italy. 

WSA-SNOX A combined flue-gas treatment process which converts the sulfur dioxide to sulfuric acid and the nitrogen oxides to nitrogen. Developed by Snamprogetti and Haldor Topsoe, based on the WSA process. A large demonstration unit was under construction in 1989. 

Predominantly cis-1,4-polybutadiene is produced by coordination polymerization with mixed catalysts.187,487,488 Three catalyst systems based on titanium, cobalt, or nickel are used in industrial practice. Iodine is an inevitable component in titanium-alkylaluminum sytems to get high cis content. Numerous different technologies are used 490,491 A unique process was developed by Snamprogetti employing a (Tr-allyl)uranium halide catalyst with a Lewis acid cocatalyst.492-494 This catalyst system produces poly butadiene with 1,4-ris content up to 99%. 

A -Formyl morpholine (FM) FORMEX process, Snamprogetti Water is added to the FM to increase its selectivity and also to avoid high reboiler temperatures during solvent recovery by distillation 40° C Perforated-tray extractor, FM density at 1.15 aids phase separation Low corrosion allows use of carbon steel equipment... 

Should MTBE be banned, what would be the logical replacement(s) There are several options available. Several refiners opted to build MTBE capacity and avoid purchasing the ether on the open market. MTBE units were an option to use the facility s isobutylenes. Several licensed processes can be used to convert existing MTBE units. Kvaerner and Lyondell Chemical Co. offer technologies to convert an MTBE unit to produce iso-octane, as shown in Fig. 18.27.12 Snamprogetti SpA and CDTECH also have an iso-octene/iso-octane process. These processes can use various feedstocks such as pure iso-butane, steam-cracked C4 raffinate, 50/50 iso-butane/iso-butene feeds, and FCC butane-butane streams. The process selectively dimerizes C4 olefins to iso-octene and then hydrogenates the iso-octene (di-iso-butene) into iso-octane. The processes were developed to provide an alternative to MTBE. The dimerization reactor uses a catalyst similar to that for MTBE processes thus, the MTBE reactor can easily be converted to... 

The Snamprogetti (SNAM) process, the synthesis section of the Stamicarbon (STAC) process and the synthesis section of the Toyo-ACES (Advanced Process for Cost and Eneigy Saving) process are described in References 108 and 110. An updated version of the STAC process, Urea 2000plus, is offered by DSM (Stamicarbon s parent company).108110... 

SP-Isoether [SnamProgetti] A process for making an Ao-octane alkylate on a plant designed to make methyl /-butyl ether. It is based on the selective dimerization of isobutylene, followed by hydrogenation to Ao-octanc. Developed by Snamprogetti in 2000. See also Nexoctane. 

Snamprogetti granulation technology has been applied in a 1,650-tpd plant operating since 1990. The plant is completely free from pollution problems. All vents are efficiently treated so that they are discharged to atmosphere practically free of ammonia and urea. Process wastewater is hydrolized within the plant to achieve boiler feedwater specification and recover ammonia and carbon dioxide. 

CDTECH/Snamprogetti SpA Isobutylene Mixed C4 hydrocarbons Integrated MTBE and MTBE backcracking processes to selectively recover high-purity (99.9%) isobutylene 7 1991... 

CDTECH/Snamprogetti SpA Isooctene/isooctane Mixed C4 hydrocarbons Isobutylene diemrization to produce isooctene. Additional process can hydrogenate isooctene to produce isooctane 2 1999... 

CDTECH/Snamprogetti SpA ETBE Mixed C4 hydrocarbons High-conversion catalytic distillation process for ETBE using C4s and ethanol 5 2000... 

Snamprogetti Spa Urea Ammonia and carbon dioxide Process is pollution-free, and energy efficient 98 2000... 

Integrating the ammonia and urea process into a single train was proposed by Snamprogetti to reduce investment and operating costs [1099] (see also Chapter 7). 

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