Furnace commercial millisecond

Figure 1 shows the yields of principal products obtained from the steam pyrolysis of the naphtha feedstock as severity is varied, while contact times are maintained within 0.01 to 0.1 second. The open circular points are data obtained in the Kellogg Millisecond Pilot Plant, while the closed points are data obtained in the Millisecond Bench Scale Unit, and the square points are the data observed with the commercial Millisecond Furnace at Tokuyama ( ). These data clearly establish that excellent correspondence exists between the experimental results from these units. The observed agreement is even more remarkable when one considers that the scale-up factors between the bench scale-pilot plant and the pilot plant-commercial furnace are of the order of 10 and 10, respectively. 

Hundreds of "balance runs" and innumerable screening runs have been made in the pilot plant on feeds ranging from ethane through heavy gas oil. The results of the most recent tests at high severity were employed in the design of the commercial Millisecond Furnace. 

In the course of commercial operations> extensive yield data were collected on various liquid feedstock operations over the full short residence time range and varying hydrocarbon partial pressure. Yields were determined in the field by a special sample conditioning and analysis system ( ) operating on the furnace effluent. The results of these studies substantiated the laboratory and pilot plant findings and confirmed that ethylene yields with the Millisecond Furnace can be increased by 10-20 wt % relative to those obtained with conventional cracking. Similar increases were achieved in the yields of other valuable co-products while the yield of methane was significantly reduced in all cases. 

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