Control Structure with Methanol Feedflow Controlled

3 Control Structure with Methanol Feedflow Controlled 

Even though the methanol feed is decreased, the C4 feed actually ends up at a new steady state that is at a higher flowrate. The distillate isobutene composition climbs to about 14mol%. 

Clearly, this control stmcture does not provide effective control for the MTBE system. The fundamental reason for this poor performance is the very low concentration of isobutene in the column. These results indicate that it is much better to flow control the C4 feed and manipulate the methanol feed. 

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