Pressure fluid bed

Several other processes that are aimed at the manufacture of gasoline from coal have been applied over the years. The main reactor in these processes uses three phase fluidization in which solid coal particles, gases, and liquids are all contacted at very high temperatures and pressures. Fluid bed dryers and fluid cokers are also used in synthetic fuels manufacmre. 

The advanced pressurized fluid-bed gasifiers currently ready for demonstration have internal diameters of around 3.6 m (12 ft) and are 20 to 28 m (66 to 92 ft) in height. Production of more than 100,000 mVh of gas (at gasifier temperature and pressure) is achieved by the advanced gasifiers, equivalent to 33,260 kg/h of bituminous coal (air blown). 

Table V. Capital Cost of Hydrocarbonization-Pressurized, Fluid-Bed Combustion Plant (1977 Dollars)...

Today the circulating fluidized bed (CFB) has become the dominating design for combustors operated at atmospheric pressure. Pressurized circulating fluidized bed combustors are under development for combined power cycle applications, but so far no clear advantages have been revealed yet. For this reason the existing commercial pressurized fluid bed systems are bubbling beds. 

After 30 years, olefin polymerization by a coordinated anionic mechanism continues to receive worldwide attention as evidenced by a voluminous patent and journal literature. Much attention has been directed to catalyst and process optimization and understanding of key reaction variables. The development of high-activity Ziegler-Natta catalysts has spurred a renewed interest in simplified processes requiring no post-treatment of the polymers. Recent announcements by Union Carbide of a low-pressure, fluid bed... 

Flue Gas Scrubbing of SO and particulates Pressurized Fluid Bed Combustion of Coal Magnetically Stabilized Fluid Bed... 

AS Jensen, Large pressurized fluid bed steam dryers. Proceedings of the IDS 96, pp. 591-597, 1996. 

Both the atmospheric and pressurized fluid bed combustors bum coal with limestone or dolomite in a fluid bed that, with recent modifications to the system, allows the limestone sorbent to take up about 90% of the sulfur that would normally be emitted as sulfur dioxide. In addition, combustion can achieved at a lower temperatnre than in a conventional combustor thereby reducing the formation of nitrogen oxide(s). 

Fluidized-bed combustors can be either atmospheric or pressurized (Yeager and Preston, 1986). The atmospheric type operates at normal atmospheric pressure while the pressurized type operates at pressures 6-16 times higher than normal atmospheric pressure. The pressurized fluid-bed boiler offers a higher efficiency and less waste products than the atmospheric fluid-bed boiler. There is also a circulating (entrained) bed combustor which allows for finer coal feed, better fuel mixing, higher efficiency, as weU as an increased sulfur dioxide capture. 

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