초록 ▼

A fluidized bed apparatus having an outer vessel provided at a lower region with a plenum chamber as well as a grid situated directly above the plenum chamber and carrying a plurality of nozzles through which gas flows from the plenum chamber into the space in the vessel above the grid. These nozzle

A fluidized bed apparatus having an outer vessel provided at a lower region with a plenum chamber as well as a grid situated directly above the plenum chamber and carrying a plurality of nozzles through which gas flows from the plenum chamber into the space in the vessel above the grid. These nozzles provide a given pressure drop in the gas flowing therethrough while as the gas flows from the plenum chamber through each nozzle there is also provided by way of a suitable structure a preliminary pressure drop, so that a two-stage pressure drop is provided in the gas flowing through each nozzle from the plenum chamber into the vessel above the grid. In this way it is possible to achieve a flow of gas above the grid sufficient to maintain the particles suspended in the fluidized bed while attrition of the particles is maintained at a minimum so that very little if any fines flow out of the vessel with gas which is formed therein. According to this method, the particles are petroleum coke particles while the gas is a mixture of steam and air maintained in the plenum chamber at a pressure of only 1-5 psig above the pressure in the bed while at the region of the interior of the vessel above the grid the temperature is on the order of 1500°-1800°F. The grid supporting the nozzles is sloped 3°to 5°downwards towards a center well and supporting member to allow solid agglomerations such as lumps of coke and slag to move radially inward into the well for withdrawal.

대표청구항 ▼

In a fluidized bed apparatus, such as a petroleum coke gasifier, an outer vessel having at a lower region thereof a plenum chamber and carrying at said lower region above said plenum chamber a grid which extends across said vessel, and said grid carrying a plurality of nozzle means distributed over

In a fluidized bed apparatus, such as a petroleum coke gasifier, an outer vessel having at a lower region thereof a plenum chamber and carrying at said lower region above said plenum chamber a grid which extends across said vessel, and said grid carrying a plurality of nozzle means distributed over said grid and communicating through said grid with said plenum chamber for receiving gas therefrom and distributing the gas into the space in said vessel over said grid for maintaining particles in a fluidized condition above said grid, each of said plurality of nozzle means providing a drop in the pressure of gas received from said plenum chamber as the gas flows out of said nozzle means into the space in the vessel above said grid, first orifice means situated adjacent said grid in the path of gas flow to each of said nozzle means to provide a preliminary drop in the pressure of the gas flowing from said plenum chamber to each nozzle means, and second orifice means at the outlet of said nozzle means to prOvide a secondary drop in the pressure of the gas flowing from said plenum chamber into the space above the grid, so that the total pressure drop between said plenum chamber and the space over said grid occurs in two distinct stages within said nozzle means.