US3666931A - Control method and means for obtaining optimum yields of refined oil and extract oil from charge oil - Google Patents
Control method and means for obtaining optimum yields of refined oil and extract oil from charge oil Download PDFInfo
- Publication number
- US3666931A US3666931A US96193A US3666931DA US3666931A US 3666931 A US3666931 A US 3666931A US 96193 A US96193 A US 96193A US 3666931D A US3666931D A US 3666931DA US 3666931 A US3666931 A US 3666931A
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- US
- United States
- Prior art keywords
- oil
- signal
- extract
- refined
- signals
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06G—ANALOGUE COMPUTERS
- G06G7/00—Devices in which the computing operation is performed by varying electric or magnetic quantities
- G06G7/48—Analogue computers for specific processes, systems or devices, e.g. simulators
- G06G7/75—Analogue computers for specific processes, systems or devices, e.g. simulators for component analysis, e.g. of mixtures, of colours
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G21/00—Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents
- C10G21/30—Controlling or regulating
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S208/00—Mineral oils: processes and products
- Y10S208/01—Automatic control
Definitions
- One object of the present invention is to control quantities of refined oil and extract oil and the temperature of the extract-mix during refining of crude oil so as to obtain optimum yields of the refined oil and the extract oil.
- Another object of the present invention is to control the flow rate of charge oil and the temperature of extract-mix during the refining of the charge oil in accordance with predicted values, determined from sensed conditions of the charge oil, for a predetermined time period and after the predetermined time period in accordance with sensed conditions of a solvent, refined waxy oil and extract oil.
- Another object of the present invention is to control the refining of charge oil in accordance with the economic values of the charge oil, extract oil and refined oil.
- FIG. 1 is a simplified block diagram of a system for refining charge oil using an automatic control system, constructed in accordance with the present invention, to obtain optimum quantities of refined oil and extract oil from the charge oil.
- FIGS. 2 through 9 are detailed block diagrams of the H computer, A computer, the 5.0 computer, the a computer, the a computer, the a computer, the A computer, the X computer, the Y computer, and the T computer blocks shown in FIG. 1.
- FIG. 10 is a block diagram of an exponential circuit of the type which may be used in the a,,,,,, computer, the a computer, the a computer, the A computer, the X computer, the Y computer and the T computer shown in FIGS. 5 through 9.
- FIG. 1 there is shown a control system for a conventional type furfural refining operation for providing an optimum yield of refined oil.
- the rate of flow of the charge oil is controlled so as to control the flow rates of refined waxy oil and extract oil.
- the temperature, which is also controlled, at which the refining of the charge oil takes place also affects the yield of the refined waxy oil and the extract oil.
- the rate of the charge oil entering a furfural refining tower 5 in a line 6 is sensed and controlled by conventional types sensing element 8, flow recorder controller 10 and valve 14.
- Sensing element 8 provides a signal to controller 10 corresponding to the flow rate of charge oil.
- Controller 10 operates valve 14 to control the rate of flow of the charge oil to tower 5 in accordance with the signal from sensing element 8 and a signal E,. Signal E, controls the set points of controller 10.
- the charge oil is also sampled by a refractive index meter 17, a flash meter 18, a viscosity meter 19, a gravity meter 20 and the effluent from those meters may be applied to tower 5 or disposed of as slop.
- Refractive index meter 17, which may be of the type described by G. C. Eltenton in US Pat. No. 2,569,127, provides a signal E corresponding to the refractive index of the charge oil.
- Flash meter 18 provides a signal E corresponding to the Cleveland Open Cup Flash Point of the charge oil.
- a suitable meter for this purpose is the Precision Scientific Automatic Flash Tester recalibrated for the Cleveland Open Cup Flash Point.
- Viscosity meter 19 provides a Although not shown, for ease of explanation, the charge oil and a furfural refining solvent entering tower 5 through lines 6 and 24, respectively, have been heated to a predetermined temperature.
- Tower 5 contains packing 26 where the charge oil and solvent are contacted in counter current flow efiecting the extraction of low viscosity index constituents of the charge oil.
- Rafi'inate including the refined waxy oil and a small amount of dissolved solvent is withdrawn through line 30.
- a temperature gradient is maintained in tower 5 by means of a cooling oil 32 having cooling water flowing through it.
- the temperature in tower 5 is sensed by conventional type sensing means 34 which provides a corresponding signal to a temperature recorder controller 37.
- Temperature recorder controller 37 which may be of a type wellknown in the art, operates a valve 38 in accordance with the signal from temperature sensing means 34 and a signal E Signal E controls the set points of temperature recorder controller 37.
- Valve 38 controls the rate of flow of the cooling water to control the temperature in tower 5.
- Temperature controller recorder 37 also provides asignal E which corresponds to the temperature T of the extract-mix.
- Raffinate'in line 30 enters a stripper 40 which strips the solvent from the raffinate to yield the refined ,waxy oil.
- the solvent after treatment for the removal of water-in any suitable manner e.g. Hydrocarbon Processing, Sept. 1966, Volume 45, Number 9, page 226) is returned to tower 5 by line 24 while the refined waxy oil is provided to dewaxing element 39 through a line 41.
- Element 40 removes the wax and provides refined oil for storage and blending with product lubricating oil.
- the refined waxy oil in line 41 is continuously sampled by a refractive index meter 17A, which providesa corresponding signal E and the effluent is either-returned to line 41 or disposed of as slop.
- Elements having a numerical designation with a suffix are identical in operation and connection to elements having the same numerical designation without a suffix.
- Sensing means 8A and a conventional type flow recorder 44 measures the rate of flow of the refined waxy oil from stripper 40 and provides a correspondingsignal E,
- Extract-mix comprising solvent and dissolved low viscosity index constituents of the charge oil is withdrawn from tower 5 through line 48 at a temperature controlled by cooling coil 32.
- the extract-mix in line 48 is passed to.a stripper 49 where the solvent is stripped from the extract oil which is discharged through a line 50.
- the recovered solvent is withdrawn through line 24 for return to tower 5 and r'e-use.
- Sensing means 88 and a flow recorder 44A senses the rate'of flow of extract oil in line 50 and provide a corresponding signal E Sensing means 8C and a flow recorder 44B'senses the flow rate of solvent in lirie 24 and provides a corresponding signal E
- the control system of the present invention provides for this condition by controlling the quality of the refined waxy oil, using predictive values, for a predetermined time period of suitable duration to allow the characteristics of the refined waxy oil and the extract oil to stabilize. After the predetermined time period has elapsed, the control system of the 7 present invention senses the conditions of the refined waxy oil and the flow rates of the extract oil and the refined waxy oil to control the process.
- Signal E corresponding to the kinematic viscosity V term in Equation 1 is applied to an H computer 55 which also receives direct current voltages E E, and E, and which provides a signal E corresponding to H in accordance with Equation 1.
- signal E is summed with voltage E,, which corresponds to the term 0.6 in Equation 1, by summing means 57.
- the resulting sum signal is amplified by conventional type logarithmic amplifiers 58, 58A to provide a signal, corresponding to the log log of the sum signal from summing means 57, to a multiplier 60.
- Subtracting means subtracts the product signal from multiplier 66 from voltage E, which is related to the term 94.9 in Equation 2, to provide a corresponding signal.
- Signal E is effectively squared by a multiplier 70 and the resulting signal is multiplied with voltag E, which corresponds to the 0.0001 coefl'lcient in Equation 2, by a multiplier 71.
- Gravity signal E is effectively squared by a multiplier 73 and the resulting signal is multiplied with voltage E,, which corresponds to the coefficient 0.0826 in Equation 2, by a multiplier 74 to provide a corresponding product signal.
- the product signal from multiplier 74 is subtracted from the product signal from multiplier 71 by subtracting means 77 to provide a signal to summing means 78.
- Subtracting means 94 subtracts the product signal from multiplier 90 from the sum signal from summing means 93 to provide signal E
- a signal E is provided by an a computer 100 in accordance with signals E E from flow recorder 44B and E.O.,,,,,, computer 70, respectively, direct current voltages E,, E,, E and E,,, asshown in FIG. 1, and Equation 4. All terms and coefficients referred to in the following description of computer 100 occur in Equation 4.
- signal E received by computer l-and corresponding to the S term is divided by voltage E,, which corresponds to the term 1,000, by a divider 101.
- the resulting signal is raised to the power of 0.35 by an exponential circuit 102, which may be of the type shown in FIG.
- Exponential circuit 146 provides a corresponding signal to a multiplier 147.
- a divider 150 divides signal E which corresponds to the flow rate S of the solvent in line 24, by voltage V, which corresponds to the term 1,000 in Equation 7.
- An exponential circuit 151 which also receives voltage V, raises the signal from divider 150 to the power of 0.5 and provides a corresponding signal.
- the signals from exponential circuits 146, and 151 are multiplied with each other by multiplier 147 to provide a product signal.
- Divider 142 divides the product signal from multiplier 138 with the product signal from multiplier 147 to provide signal E;,.,.
- the quality of the refined oil is a constant for different sets of variable conditions.
- the flow rate of the charge oil and the temperature of the extract-mix leaving tower 5 may be simultaneously varied without changing the quality of the refined oil.
- the flow rate of the charge oil and the temperature of the extract-mix are controlled in accordance with the following equations to provide optimum refining of the charge oil.
- A is the predicted characteristic constant A for the charge stock during the predetermined time period and the actual characteristic constant A during the remainder of the refining process
- X is the maximum profit flow rate of the extract oil in line 50
- b is the value of the refined oil in dollars per barrel
- e is the value of the charge oil in dollars per barrel
- d is the value of extract oil in dollars per barrel
- Y is the maximum profit flow rate of refined oil in line 41
- 2 is the maximum profit flow rate of charge oil in line 23
- TLQMMP is the maximum profit temperature of the extract-mixfrom tower 5.
- the maximum profit flow rate of extract oil in line 50 is determined by an X computer 160 which provides a corresponding signal E to summing means 161.
- Summing means sums signal E with a signal E from a Y computer 162, which corresponds to the maximum profit flow rate of the refined waxy oil in line 41, to provide signal E corresponding to the maximum profit flow rate of the charge oil in line 23, to flow recorder controller 10.
- Switch 166 which may be of a type manufactured by Eagle Signal Co., Moline, Illinois, as model HPS Series, Cycl-I-ilex Reset Timer, passes signal E from A computer 100, as a signal E duringthe predetermined time to computer 160. Switch 66 then passes signal 5,, from A computer 118 as signal E thereafter to X computer 160.
- Computer 160 provides signal E in accordance-with the passed signal E from switch 166, direct current voltages V V V V, and V,,,, and Equation 8. All the terms referred to in the-following description of X computer 160 are contained in Equation 8.
- Subtracting means 202 subtracts the output from divider 201 from voltage V,, corresponding to the term 323 in Equation ll to provide signal E I
- a digital computer such as an 1800 Process Control Computer manufactured by IBM may be used.
- control means includes first signal means for providing signals corresponding to a first actual characteristic 0. IA and a desired characteristic a of the refined oil in accordance with the following equations:
- the first signal means includes a first analog computer receiving direct current voltages corresponding to the numeric values 0.935, 323, 1,000 in the first mentioned equation and connected to the flow rate sensing means and providing the signal corresponding to 0.1.4,, in accordance with the first mentioned equation, the received direct current voltages and the signals corresponding to the flow rates X and Y of the refined waxy oil and the extract oil, respectively, a second analog computer connected to the flow rate sensing means and receiving a direct current voltage corresponding to the exponent 0.65 in the second mentioned equation and providing a signal corresponding to the tenn a in the second mentioned equation in accordance with the second mentioned equation, the signals from the flow rate sensing means corresponding to the flow rates X, and Y of the extract oil and-the refined waxy oil, respectively, and the received direct current voltage; and a third analog computer connected to the second analog computer and to the difference means and receiving direct current voltages corresponding to the ARI term and the exponent 3.0 in the third mentioned equation and providing the signal
- the sensing means further comprises means for sensing the flash point Fl of the crude oil, and providing a corresponding signal; means for sensing the API gravity of the charge oil and providing a signal corresponding thereto, and means for sensing the kinematic viscosity V,, and providing a corresponding signal; and the control means further includes second signal means, connected to the kinematic viscosity sensing means, to the API gravity sensing means, to the other refractive index meter, to the flash point sensing means and to the flow rate sensing means for providing signals corresponding to predicted first and second characteristics of the refined waxy oil in accordance with the signals from the kinematic viscosity sensing means, from the API gravity sensing means, from the other refractive index meter, from the flash point sensing means and from the flow rate sensing means and with the following equations:
- H 870 log log(V +O.6)+ 154, 01A 94.9.- 0.149 H 0.0826(API) 0,0001 1')"' l-j.(). 0.1281 [1,000 (RA -1.42) 0. l(F!]-C,( 100 I VITI"U
- H is the Bell and Sharp viscosity function of the. charge oil at 210 F.
- V is the sensed kinematic viscosity of the charge oil at 210 F.
- A is a predicted first characteristic of the refined waxy oil, E .0.
- second signal means afterthe predetennined time period
- the second signalmeans includes a seventh analog computer connected to the kinematic viscosity sensing means and receiving direct current voltages corresponding to the terms 870, 0.6 and 154 in the eighth mentioned equation and providing a signal corresponding to the Bell and Sharpe viscosity function]! in accordance with the signal from the kinematic viscosity sensing means, the received direct current voltages, and the eighth mentioned equation; an eighth analog computer connected to the seventh computer, to the API gravity sensing means and to the switching means and receiving direct current voltages corresponding to the terms 94.9, 0.149, 0.0826 and 0.0001 in the ninth mentioned equation for providing a signal to the switching means corresponding to 0.
- a method for controlling a refinery operation wherein charge oil is mixed with solvent in a refining tower to provide a stream of raffinate and a stream of extract-mix to strippers is the sensed refractive index of the which strip the solvent from the raffinate and the extract-mix to yield refined waxy oil and extract oil, the stripped solvent is returned to the refining tower and the refined waxy oil is subsequently dewaxed to provide refined oil; which comprises sensing conditions of the refined waxy oil, the extract oil and the solvent; providing signals corresponding to the sensed conditions; providing signals corresponding to the economic values of the charge oil, the refined oil and the extract oil; and controlling some of the conditions of the refined waxy oil, the extract oil and the extract-mix in accordance with the condition signals and the value signals.
- the sensed conditions are the refractive index of the charge oil, the flow rate and the refractive index of the refined waxy oil, the fiow rate of the extract oil, the temperature of the extract-mix and the flow rate of the solvent;
- the controlled conditions are the flow rates'of the refined waxy oil and the extract oil;
- the condition signals 0.1.4, and a correspond to the sensed conditions in accordance with the following equations:
- T- c [100 v1 1-, c 1 lin 68 I 6 2 TARG a. o umn 3, es and 9, should d lOO- rea.
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- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Computer Hardware Design (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Organic Chemistry (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US9619370A | 1970-12-08 | 1970-12-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3666931A true US3666931A (en) | 1972-05-30 |
Family
ID=22256243
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US96193A Expired - Lifetime US3666931A (en) | 1970-12-08 | 1970-12-08 | Control method and means for obtaining optimum yields of refined oil and extract oil from charge oil |
Country Status (12)
Country | Link |
---|---|
US (1) | US3666931A (pt) |
BE (1) | BE776308A (pt) |
BR (1) | BR7108100D0 (pt) |
CA (1) | CA971122A (pt) |
DE (1) | DE2160881A1 (pt) |
ES (1) | ES397538A1 (pt) |
FR (1) | FR2117898B1 (pt) |
GB (1) | GB1336197A (pt) |
IT (1) | IT953151B (pt) |
NL (1) | NL7116759A (pt) |
TR (1) | TR16797A (pt) |
ZA (1) | ZA717831B (pt) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3826904A (en) * | 1970-11-17 | 1974-07-30 | Texaco Inc | Method and apparatus for the optimum blending of lubricating base oils and an additive |
US4869809A (en) * | 1988-05-09 | 1989-09-26 | Uop | Aromatics extraction process control |
US5213696A (en) * | 1991-12-23 | 1993-05-25 | Star Enterprise | Automatic dewaxing filter washing system and method |
US6295485B1 (en) | 1999-01-29 | 2001-09-25 | Mobil Oil Corporation | Control of lubricant production by a method to predict a base stock's ultimate lubricant performance |
US6317654B1 (en) | 1999-01-29 | 2001-11-13 | James William Gleeson | Control of crude refining by a method to predict lubricant base stock's ultimate lubricant preformance |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3285846A (en) * | 1963-09-18 | 1966-11-15 | Mobil Oil Corp | Automated lubricating oil refining |
US3458691A (en) * | 1958-12-29 | 1969-07-29 | Universal Oil Prod Co | Process control system |
US3458432A (en) * | 1967-06-23 | 1969-07-29 | Texaco Inc | Lube oil refining process |
US3539784A (en) * | 1967-07-31 | 1970-11-10 | Texaco Inc | Process instrumentation and control through measurements of time-separated process variables |
-
1970
- 1970-12-08 US US96193A patent/US3666931A/en not_active Expired - Lifetime
-
1971
- 1971-11-08 CA CA127,167A patent/CA971122A/en not_active Expired
- 1971-11-22 ZA ZA717831A patent/ZA717831B/xx unknown
- 1971-11-25 GB GB5470971A patent/GB1336197A/en not_active Expired
- 1971-11-30 ES ES397538A patent/ES397538A1/es not_active Expired
- 1971-12-02 TR TR16797A patent/TR16797A/xx unknown
- 1971-12-03 FR FR7143430A patent/FR2117898B1/fr not_active Expired
- 1971-12-06 BE BE776308A patent/BE776308A/xx unknown
- 1971-12-06 IT IT32078/71A patent/IT953151B/it active
- 1971-12-07 NL NL7116759A patent/NL7116759A/xx not_active Application Discontinuation
- 1971-12-07 BR BR8100/71A patent/BR7108100D0/pt unknown
- 1971-12-08 DE DE19712160881 patent/DE2160881A1/de active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3458691A (en) * | 1958-12-29 | 1969-07-29 | Universal Oil Prod Co | Process control system |
US3285846A (en) * | 1963-09-18 | 1966-11-15 | Mobil Oil Corp | Automated lubricating oil refining |
US3458432A (en) * | 1967-06-23 | 1969-07-29 | Texaco Inc | Lube oil refining process |
US3539784A (en) * | 1967-07-31 | 1970-11-10 | Texaco Inc | Process instrumentation and control through measurements of time-separated process variables |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3826904A (en) * | 1970-11-17 | 1974-07-30 | Texaco Inc | Method and apparatus for the optimum blending of lubricating base oils and an additive |
US4869809A (en) * | 1988-05-09 | 1989-09-26 | Uop | Aromatics extraction process control |
US5213696A (en) * | 1991-12-23 | 1993-05-25 | Star Enterprise | Automatic dewaxing filter washing system and method |
US6295485B1 (en) | 1999-01-29 | 2001-09-25 | Mobil Oil Corporation | Control of lubricant production by a method to predict a base stock's ultimate lubricant performance |
US6317654B1 (en) | 1999-01-29 | 2001-11-13 | James William Gleeson | Control of crude refining by a method to predict lubricant base stock's ultimate lubricant preformance |
Also Published As
Publication number | Publication date |
---|---|
AU3629271A (en) | 1973-06-07 |
GB1336197A (en) | 1973-11-07 |
BR7108100D0 (pt) | 1973-04-10 |
ZA717831B (en) | 1972-08-30 |
DE2160881A1 (de) | 1972-06-29 |
NL7116759A (pt) | 1972-06-12 |
ES397538A1 (es) | 1974-05-16 |
BE776308A (fr) | 1972-06-06 |
TR16797A (tr) | 1973-05-01 |
FR2117898B1 (pt) | 1974-10-31 |
IT953151B (it) | 1973-08-10 |
FR2117898A1 (pt) | 1972-07-28 |
CA971122A (en) | 1975-07-15 |
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