Designer feeds

Ideally, a well-designed feed and catalyst injection system will achieve the following objectives ... 

Maintain a mitrimum of 1 PSi pressure differential across the Slide Valves Install "Radial designed Feed Nozzles Install an automated shutdown System... 

Dissolved oxygen (DO) should be reduced to the lowest practical level, which is achieved by the use of a properly designed feed tank or deaerator. 

Company Catalyst designation Feed and/or application Form Bulk density (lb/ft3) Support Catalytic metals Notes... 

In addition, the complex problem of unit design (feed nozzles, regenerators, strippers, etc.) and operation has to be addressed properly (15) in order to further extend the limits (higher Ni, V, Fe contaminants as well as more refractory feedstocks) of feeds processable by FCC (16). 

Eront-End Engineering and Design (FEED) focuses on obtaining accurate cost estimates for the major items of process equipment and further definition of the most sensitive parts of the overall project cost. It is denoted Eront-End because this is performed prior to final corporate board and financial approval for the overall project. EEED costs typically 5 to 10% of the overall project cost - thus for a 1,000 million project expenditure of about 100 million will be required. Only after the feasibility and FEED will the cost error be in the vicinity of +1-5%. In many instances, especially for new technology or for a remote location or offshore, the error will still be in the region of +/-10% or more. 

Irmovatively designed feed screw systems are used commercially in roller compactors worldwide. An example is shown in Fig.6. 

As with other unit operations, the scale-up success for roller compaction is dependent on understanding and identifying the process parameters that will influence the quality of the final product. The typical parameters that can influence compacted ribbon characteristics and the resultant final product qualities are hopper design, feed screw design, and roll configuration. 

Solution The sparger (feedpipe) was turned so that the holes were on top rather than the bottom. This ensured that the sparger remained full of liquid even at low feed rates. A deflector was installed above the orifices to keep feed from impinging on the tray above. This solution was better than the alternate of plugging holes, because the hole area would then have been undersized at the higher design feed rates. 

Equal-molal overflow could be assumed, but if the calculations are done by computer, an enthalpy balance would probably be made and the change in pressure from stage to stage would also be allowed for. The calculations are continued in this fashion, alternating the use of equilibrium and material-balance relationships, until the composition is close to that of the feed. Similar calculations are carried out for the lower section of the column starting with an estimated reboiler or bottoms composition. The next step is to match the Compositions at the feed stage for the two sets of calculations. Based on the differences for individual components, the product compositions are adjusted and the calculations repeated until all errors fall below a specified value. In some procedures, the number of plates and the feed plate are fixed beforehand, and the calculations are repeated for different reflux ratios until the desired match is obtained at the designated feed plate. 

Blade design, feed rate, feed distribution, temp, level, At, drop-wise cond. Wiper speed, 200 r.p.m. 

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