# US 9,433,877 B2 · Settling-length optimization by dispersion band positioning apparatus and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,433,877 B2 - Document ID: US9433877B2 - Status: Granted - Kind: B2 - Application number: 14/104,916 - Filed: 2013-12-12 - Published: 2014-10-23 - Granted: 2016-09-06 - Earliest claimed: 2013-04-22 - Assignees: Econova, Inc. - Applicants: Econova, Inc. - Inventors: C. Michael Miller; D. Andrew Bell; Ngai Keung Tam - Web page: https://patentgrep.com/patent/US9433877B2 ## CPC - B01D 17/0217: {by centrifugal force} - B01D 17/0214: {with removal of one of the phases} - B01D 17/12: Auxiliary equipment particularly adapted for use with liquid-separating apparatus, e.g. control circuits - B04B 1/02: without inserted separating walls - B04B 1/04: with inserted separating walls - B04B 5/0442: {with means for adding or withdrawing liquid substances during the centrifugation, e.g. continuous centrifugation} - B04B 11/02: Continuous feeding or discharging; Control arrangements therefor - B04B 13/00: Control arrangements specially designed for centrifuges; Program control of centrifuges (control arrangements for feed, charge or discharge B04B11/00) - C02F 1/008: {Control or steering systems not provided for elsewhere in subclass C02F} - C02F 1/20: by degassing, i.e. liberation of dissolved gases (degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D) - C02F 1/38: by centrifugal separation - C02F 1/40: Devices for separating or removing fatty or oily substances or similar floating material (cleaning or keeping clear the surface of open water from oil or like materials E02B15/04; devices in sewers for separating liquid or solid substances from sewage E03F5/14, e.g. for use in drains leading to the sewer E03F5/16) - B04B 2013/006: {Interface detection or monitoring of separated components} - C02F 1/286: {using natural organic sorbents or derivatives thereof} - C02F 2101/32: Hydrocarbons, e.g. oil - C02F 2103/10: from quarries or from mining activities - C02F 2209/03: Pressure - C02F 2301/022: Laminar - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B04B: CENTRIFUGES (high-speed drum mills B02C19/11; domestic spin driers D06F; analysing, measuring or monitoring physical or chemical properties of samples during centrifuging, see the relevant subclasses for these procedures, e.g. G01N) - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) ## Abstract A system operating as a centrifugal, liquid-liquid separator may be controlled, and even optimized, by automatic control of back pressure to establish an optimum position of the dispersion band therein. Optimizing to minimize impurities (from each other) in each of two separated phases is possible, even simultaneously, by reliance on a processor setting the settling lengths of both heavy and light phases at the same value. Settling length, defined in accordance with the invention, reflects a settling velocity multiplied by a residence time. Equating these lengths, for droplets of each in the other liquid, provides superior results over conventional settling theory maximizing settling area. Equalization of residence times did not provide an improvement over conventional settling theory. ## Claims ### Claim 1 A method comprising: providing a processor controlling a pressure; separating first and second liquids from one another in a separator characterized by an inlet receiving a mixture of the first and second liquids, a dispersion band positioned between the first and second liquids; a first outlet discharging the first liquid, and a second outlet discharging the second liquid; detecting a cut reflecting flows through the inlet and at least one of the first and second outlets; positioning, by the processor, the dispersion band, automatically, based on the cut; and positioning, by the processor, the dispersion band at a location corresponding to equality between a first settling distance corresponding to droplets of the second liquid migrating through the first liquid and a second settling distance corresponding to droplets of the first liquid migrating through the second liquid. ### Claim 2 (depends on 1) The method of claim 1, further comprising: detecting, by the processor, the cut; and positioning, by the processor, the dispersion band by changing the pressure differential between the first and second outlets, based on the value of the cut. ### Claim 3 (depends on 1) The method of claim 1, wherein the processor operates as part of a control system comprising: an inlet flow meter detecting an inlet flow rate of the mixture into the separator; a first outlet flow meter detecting a flow rate of the first liquid through the first outlet; a second outlet flow meter detecting a second flow rate of the second liquid through the second outlet; and the processor, programmed to automatically adjust a valve to control the differential. ### Claim 4 (depends on 1) The method of claim 1, further comprising: sensing a first pressure proximate the first outlet; sensing a second pressure proximate the second outlet; comparing a differential between the first and second pressures; and positioning a control valve automatically to control the differential. ### Claim 5 (depends on 1) The method of claim 1, further comprising positioning the dispersion band by the processor automatically adjusting a control valve controlling a differential of pressure between the first and second outlet. ### Claim 6 (depends on 1) The method of claim 1, wherein the settling distance is a product of a settling velocity and a residence time corresponding to the separator, the first liquid, and the second liquid. ### Claim 7 (depends on 1) The method of claim 1, wherein the first liquid corresponds to a first residence time reflecting a first bulk flow thereof from the inlet to the first outlet. ### Claim 8 (depends on 7) The method of claim 7, wherein the second liquid corresponds to a second residence time reflecting a second bulk flow thereof from the inlet to the second outlet. ### Claim 9 (depends on 1) The method of claim 1, wherein the separator is a rotating separator having a diameter tapering along the direction of flow between the inlet and the first outlet. ### Claim 10 A method comprising: selecting a separator characterized by an inlet receiving a mixture comprising first and second liquids; establishing in the separator a dispersion band positioned between a bulk flow of the first liquid and the second liquid; discharging the first liquid through a first outlet and the second liquid through a second outlet; determining a cut of one of the first and second liquids; controlling the position of the dispersion band by automatically adjusting a pressure differential between the first and second outlets, based on the cut; and automatically positioning the dispersion band to equate a first settling distance of the first liquid to a second settling distance of the second liquid. ### Claim 11 (depends on 10) The method of claim 10, wherein each of the first and second settling distances is a product of a settling velocity and a residence time corresponding to properties of the separator, the first liquid, and the second liquid. ### Claim 12 (depends on 11) The method of claim 11, wherein: the first settling distance corresponds to a droplet of the second liquid migrating through the first liquid; and the second settling distance corresponds to a droplet of the first liquid migrating through the second liquid. ### Claim 13 (depends on 12) The method of claim 12, further comprising: providing a control system; detecting, by the control system, an inlet flow rate of the mixture into the separator; detecting, by the control system, a first flow rate of the first liquid through the first outlet; detecting, by the control system, a second flow rate of the second liquid through the second outlet; and adjusting automatically, by the control system, the pressure differential, based on a ratio of at least one of the first and second flow rates to the inlet flow rate. ### Claim 14 (depends on 13) The method of claim 13, wherein the control system comprises: a first sensor sensing a first pressure proximate the first outlet; a second sensor sensing a second pressure proximate the second outlet; a comparator automatically reporting a differential between the first and second pressures; and a control valve automatically controlling the differential by increasing resistance to one of the first and second flow rates. ### Claim 15 (depends on 10) The method of claim 10, further comprising: programming a control system to position the dispersion band at a location corresponding to equality between a first settling distance corresponding to droplets of the at least one second liquid migrating through the at least one first liquid and a second settling distance corresponding to droplets of the at least one first liquid migrating through the at least one second liquid; and maintaining the equality over a range of changes in the cut. ### Claim 16 (depends on 15) The method of claim 15, wherein: the separator is a rotating separator of variable diameter tapering upward from proximate the inlet to proximate the first outlet along an axial direction; and the method further comprises optimizing separation quality of one of the first and second liquids from one another. ### Claim 17 (depends on 10) The method of claim 10, further comprising: providing a comparator, connected to first and second pressure sensors; sensing a first pressure corresponding to the first outlet and a second pressure corresponding to the second outlet; controlling, by the comparator, a pressure differential between the first and second pressures by setting a control valve to resist at least one of the first and second flows. ### Claim 18 An apparatus comprising: a separator, separating a first liquid and a second liquid from each other; the separator, characterized by an inlet receiving a mixture of the first and second liquids and discharging the first and second liquids from respective first and second outlets; the separator, establishing a dispersion band therewithin positioned between a bulk of the first liquid and a bulk of the second liquid; a control system positioning the dispersion band automatically, based on a cut of one of the first and second liquids discharging from the separator; and the control system, further programmed to position the dispersion band to effectively equalize the settling length of the first liquid with the settling length of the second liquid.