Combination octane number control of distillation column overhead and blending control

Claim 2

The system of claim 1 wherein said reflux flow varying means comprises a flow control loop including a flow controller having an adjustable set point regulating the rate of flow of reflux through said reflux conduit means, said setpoint being adjusted in response to said overhead octane output signal.

Claim 3

The system of claim 3 further characterized in the provision of means to sense the temperature in said column at a second locus, temperature control means having an adjustable setpoint connecting with said temperature sensing means and developing a temperature output signal, and means transmitting the last-mentioned output signal to the setpoint of said flow controller, means transmitting said overhead octane output signal to the temperature control means setpoint whereby the setpoint is adjusted responsive to overhead octane number.

Claim 4

The system of claim 4 wherein said temperature sensing means is located in said rectification zone.

Claim 5

The system of claim 5 wherein said second locus is below said first locus.

Claim 6

The system of claim 6 wherein said distillation column contains a plurality of fractionation trays and said temperature sensing means is located several trays below said first locus.

Claim 7

The system of claim 1 wherein said octane blending means comprises a flow control loop including a flow controller which controls the blending of an octane modifying stream with said overhead make and has an adjustable setpoint regulating the rate of flow of said octane modifying stream, said setpoint being adjusted in response to said volumetric-octane output signal.

Claim 8

The system of claim 8 wherein said octane modifying stream comprises tetraethyl lead.

Claim 9

The systm of claim 8 wherein said octane modifying stream comprises butane.

Claim 10

The system of claim 8 wherein said octane modifying stream comprises an aromatic selected from the group consisting of benzene, toluene and xylene.

Claim 11

The system of claim 8 wherein said octane modifying stream comprises a gasoline having an octane number higher than the octane number of said overhead stream.

Claim 12

In combination with a continuous flow, fractional distillation column, the feed to which comprises a gasoline fraction, the overhead from which omprises the lower boiling components of said fraction and the bottoms from which comprises the higher boiling components of said fraction, said column including a rectification zone having a reflux conduit means in communication therewith at a first locus and means to supply reflux to said reflux conduit means, a control system for said column comprising: a. means operatively associated with said reflux conduit means to vary the flow of reflux to said rectification zone; b. a hydrocarbon analyzer comprising a stabilized cool flame generator with a servo-positioned flame front receiving a sample of said column overhead and developing an overhead octane output signal which provides a measure of sample octane number; c. means transmitting said overhead octane output signal to said reflux flow varying means whereby the flow of reflux to said rectification zone is regulated responsive to octane number of said column overhead and said octane number is thereby maintained at a substantially constant predetermined level; d. flow measurement means operatively associated with the overhead streams to measure the flow rate of overhead make and produce an overhead flow rate output signal; e. means transmitting said overhead flow rate output signal and said overhead octane output signal to a volume-octane measurement means which means produces a volumetric-octane output signal responsive to said octane and flow rate output signals; and f. means transmitting said volumetric-octane output signal to an octane blending means which comprises a flow control loop including a flow controller which controls the blending of an octane modifying stream with said overhead make and has an adjustable setpoint regulating the rate of flow of said octane modifying stream, said setpoint being adjusted in response to said volumetric-octane signal.

Claim 13

The system of claim 13 wherein said octane modifying stream comprises tetraethyl lead.

Claim 14

The system of claim 13 wherein said octane modifying stream comprises butane.

Claim 15

The system of claim 13 wherein said octane modifying stream comprises an aromatic selected from the group consisting of benzene, toluene and xylene.

Claim 16

The system of claim 13 wherein said octane modifying stream comprises a gasoline having an octane number higher than the octane number of said overhead stream.

Claim 17

In combination with a continuous flow, fractional distillation column, the feed to which comprises a gasoline fraction, the overhead from which comprises the lower boiling components of said fraction and the bottoms from which comprises the higher boiling components of said fraction, said column including a rectification zone having a reflux conduit means in communication therewith at a first locus and means to supply reflux to said reflux conduit means, a control system for said column comprising: a. means operatively associated with said reflux conduit means to vary the flow of reflux to said rectification zone; b. a hydrocarbon analyzer comprising a stabilized cool flame generator with a servo-positioned flame front receiving a sample of said column overhead and developing an overhead octane output signal which provides a measure of sample octane number; c. means transmitting said overhead octane output signal to said reflux flow Varying means whereby the flow of reflux to said rectification zone is regulated responsive to octane number of said column overhead and said octane number is thereby maintained at a substantially constant predetermined level; d. flow measurement means operatively associated with the overhead stream to measure the flow rate of overhead make and produce an overhead flow rate output signal; e. means transmitting said overhead flow rate output signal and said overhead octane output signal to a volume-octane measurement means which means produces a volumetric-octane output signal responsive to said octane and flow rate output signals; and f. means transmitting said volumetric-octane output signal to an octane blending means which comprises a flow control loop including a flow controller which controls the blending of an octane modifying stream with said overhead make and has an adjustable setpoint regulating the rate of flow of said overhead make to be blended with said modifying stream, said setpoint being adjusted in response to said volumetric-octane signal.