ALMA process

The product stream contains gases and soflds. The soflds are removed by using either cyclones, filters, or both in combination. Cyclones are devices used to separate soflds from fluids using vortex flow. The product gas stream must be cooled before being sent to the collection and refining system. The ALMA process uses cyclones as a primary separation technique with filters employed as a final separation step after the off-gas has been cooled and before it is sent to the collection and refining system (148). As in the fixed-bed process, the reactor off-gas must be incinerated to destroy unreacted butane and by-products before being vented to the atmosphere. 

Fluidized-bed reaction systems are not normally shut down for changing catalyst. Fresh catalyst is periodically added to manage catalyst activity and particle size distribution. The ALMA process includes faciUties for adding back both catalyst fines and fresh catalyst to the reactor. 

Other catalytic reactions carried out in fluidized-bed reactors are the oxidation of naphthalene to phthalic anhydride [2, 6, 80] the ammoxidation of isobutane to mcthacrylonitrilc [2] the synthesis of maleic anhydride from the naphtha cracker C4 fraction (Mitsubishi process [81, 82]) or from n-butane (ALMA process [83], [84]) the reaction of acetylene with acetic acid to vinyl acetate [2] the oxychlorination of ethylene to 1,2-di-chloroethane [2, 6, 85, 86] the chlorination of methane [2], the reaction of phenol with methanol to cresol and 2,6-xylenol [2, 87] the reaction of methanol to gasoline... 

Fluidized-bed reactors have proposed as alternatives to circumvent the problems mentioned above (ALMA process, Alusuisse, Lummus). These allow better control of the temperature and higher feed concentrations. In addition the reactor system is less prone to explosions. A major problem in this reactor is attrition of the catalyst. In recent literature this problem has received a great deal of attention. A second drawback of the fluidized-bed reactor is the intrinsic mixing behaviour, which lowers the conversion. 

Economics The ALMA process produces high-quality product with attractive economics. The fluid-bed process is especially suited for large single-train plants. 

The production from butane had been successfully applied beginning in the 1970s. Nowadays the available technologies use both fixed- and fluidised-bed reactors. The ALMA process, which is using a fluid bed reactor and solvent-based MA recovery, was developed in the 1980s and improvements have since been made in both the process and the catalyst. 

Lonza Intermediates and Additives (Algroup) ALMA process Optimisation of the phthalyc anhydride production process... 

A schematic flow diagram for the ALMA fluidized-bed process is shown in Figure 2 (121). Compressed air and butane are typically introduced... 

Fig. 2. Schematic flow diagram of the ALMA fluidized-bed process (121). BFW BFW = boiler feed water.

ALMA [Alusuisse maleic anhydride] A process for making maleic anhydride by oxidizing -butane, using a fluid bed reactor and a special organic solvent recovery system. The catalyst contains vanadium and phosphoms on iron oxide. Developed jointly by Alusuisse Italia and ABB Lummus Crest. First licensed to Shin-Daikowa Petrochemical Company, Yokkaichi, Japan, in 1988. The world s largest plant plant was built for Lonza in Ravenna, Italy, in 1994. 

Dimersol G A process for dimerizing propylene to a mixture of isohexenes, suitable for blending into high-octane gasoline. The process is operated in the liquid phase with a dissolved homogeneous catalyst. Developed by IFP and first operated at Alma, MI, in 1977. 

Oxidation of n-butane and butenes requires higher reaction temperatures (400-480°C). Since more water is produced in this reaction, most of the product is recovered in the form of maleic acid. The currently best process is the Alma (Alusuisse) process.1015-1018 Its main features are a fluidized-bed reactor and an anhydrous product recovery. Because of the better temperature control, a lower air hydrocarbon ratio can be employed (4 mol% of n-butane). Instead of absorption in water, maleic anhydride is recovered from the reactor effluent gas by a high-boiling organic... 

Garagash, l.A. 1983. On brittle failure of elastic bodies with large number of cracks. In Mechanics of Tectonic Processes. Alma-Ata Nauka. 

Burov, I.S., Mosse, A.L., Pechkovsky, YY, Chelnokov, A.A. (1970), Plasma-Chemical Process of P2O5 Production from Natural Phosphates, in Physics, Engineering and Applications of Low-Temperature Plasma, Nauka (Science), Alma-Ata, Kazakhstan. 

A.A. Bol shov, A.D. Pomogailo, I.D. Leonov, in Kompleksnaya Pererabotka Mangyshlakskoi Nefti (Complex Processing of Mangyshlak Petroleum), Nauka, Alma-Ata, 1972, Vol. 4, p. 110. 

Kaipov DK (1976) Nuclear gamma resonance and its related processes. Naul, Alma Ata Kajcsos Z, Alflen M, Spiering H, Gutlich P, Albrecht R, Schulze R, Kurz R (1986) Hyperfine Interact 29 1551 Kajcsos Z, Sauer Ch, Holz rth A, Kurz R, Zinn W, Ligtenberg MAC, Van Aller G (1988) Nucl Instr Meth Phys Res B 34 384... 

U.S., but by 1920 there were only two left Dow and the American Magnesium Corp. Key in the development of Dow s electrolytic magnesium process was W.R. Veazey, a Dow consultant who was on the staff at the Case Institute in Cleveland, Dow s Alma Mater. 

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