WO1998038556A1 - A method of regulating the level in a buffer tank - Google Patents

A method of regulating the level in a buffer tank Download PDF

Info

Publication number
WO1998038556A1
WO1998038556A1 PCT/SE1998/000337 SE9800337W WO9838556A1 WO 1998038556 A1 WO1998038556 A1 WO 1998038556A1 SE 9800337 W SE9800337 W SE 9800337W WO 9838556 A1 WO9838556 A1 WO 9838556A1
Authority
WO
WIPO (PCT)
Prior art keywords
tank
level
outflow
regulating
inflow
Prior art date
Application number
PCT/SE1998/000337
Other languages
French (fr)
Inventor
Tomas Skoglund
Original Assignee
Tetra Laval Holdings & Finance S.A.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Tetra Laval Holdings & Finance S.A. filed Critical Tetra Laval Holdings & Finance S.A.
Priority to US09/380,152 priority Critical patent/US6311711B1/en
Priority to EP98908374A priority patent/EP0965075B1/en
Priority to AU66419/98A priority patent/AU6641998A/en
Priority to DE69814598T priority patent/DE69814598T2/en
Priority to AT98908374T priority patent/ATE240543T1/en
Publication of WO1998038556A1 publication Critical patent/WO1998038556A1/en

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D9/00—Level control, e.g. controlling quantity of material stored in vessel
    • G05D9/12—Level control, e.g. controlling quantity of material stored in vessel characterised by the use of electric means
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/0318—Processes
    • Y10T137/0324—With control of flow by a condition or characteristic of a fluid
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7287—Liquid level responsive or maintaining systems
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8158—With indicator, register, recorder, alarm or inspection means
    • Y10T137/8342—Liquid level responsive indicator, recorder or alarm

Definitions

  • the present invention relates to a method of regulating the level in a buffer tank, the tank being connected to conduits for inflow Fi and outflow
  • the method comprising periodic measurement and regulation of the inflow Fi into the tank and periodic measurement of the product level L in the tank, as well as indicated level norm values.
  • Buffer tanks occur regularly within different process industries for creating a margin between the different parts in the process or between the process proper and, for example, pre-treatment or final packing. Buffer tanks are dimensioned to capable of receiving product if a disruption were to occur between the different parts in or peripheral to the process.
  • the buffer tank is to afford space to be able to regulate one part of, for example, the process if another part in or peripheral to the process were suddenly to stop or change the flow by other means.
  • the buffer tank should be of such dimensions as to accommodate that product volume which is required before regulation could take place.
  • the buffer tank must also retain such a large product volume that there is no risk of it being emptied before regulation can be put into effect.
  • the product may spill over and thereby be lost, or the tank may be emptied and thereby impede or disrupt the outflow.
  • the intention is that the buffer tank should be as little as possible, since large tanks are expensive and bulky.
  • a simple method of regulating the level in a buffer tank is the so-called on/ off regulation method, which implies that the level is regulated in that the inflow is started or stopped when necessary. This is often an unsuitable method, since it inevitably disrupts the process.
  • Another common method for regulating the level in a buffer tank is by selecting a tank which is so large that a normal position for product level is situated approximately in the centre of the tank. Then there is space for regulating both upwards and downwards in the tank and the dimensions of the tank are twice the requisite space in order to have time to regulate the process. Apart from the fact that a large tank involves considerable overhead costs and that it requires a large floor space, it also holds a larger quantity of product which runs the risk of being left standing in the buffer tank. Many products in the food industry are today highly specialised and are relatively expensive to produce, which is a further factor guiding the wish to employ as small buffer tanks as possible.
  • One object of the present invention is to create a method of regulating the level in a buffer tank which makes for the employment of a tank which is only half as large as those tanks which are normally employed as buffer tanks.
  • a further object of the present invention is that only the inflow into the tank and the level in the tank are measured. Yet a further object of the present invention is that the method be reliable and dependable such that the process quality is not jeopardised.
  • Fig. 1 shows a flow diagram in which the method according to the present invention may be employed.
  • the Drawing shows a process 1 which may be mixing process or the like where great accuracy is required in order to maintain a uniform product quality.
  • a conduit 2 departs with the flow Fj, this flow being periodically measured using a conventional flowmeter 3.
  • the flow Fi must be regulated such that it is altered relatively slowly so as not to disrupt the process 1.
  • the conduit 2 is connected to a buffer tank 4 in which the flow Fi constitutes the flow Fi into the tank 4.
  • the level L of the enclosed product is periodically measured with the aid of a conventional level gauge 5.
  • the tank 4 is further connected to a conduit 6 for the outflow F 2 out of the tank 4.
  • the conduit 6 leads the product on to further treatment, such as, for example, packing the product, which may be put into effect in one or more filling machines 7.
  • Reference numeral 7 in Fig. 1 may also, for instance, symbolise a sterilizer.
  • the process 1 is controlled with the aid of a PLC unit 8
  • the PLC unit 8 periodically reads off a signal 9 from the flowmeter 3. The measurement of the level in the tank 4 also gives an input signal 10 to the PLC unit 8, which this reads off periodically. From the PLC unit 8, one or more signals 11 are emitted to conventional control valves in the process 1 where, in turn, they act on and control the process 1.
  • the process 1 has an inherent inertia so that a signal for change of the flow of the process 1 may only be implemented such that the process is changed relatively slowly.
  • Aftertreatment, which in Fig. 1 consists of one or more filling machines 7, may start and stop independently of one another almost instantaneously.
  • the buffer tank 4 thus constitutes the margin between, on the one hand, the process 1 which can only be regulated relatively slowly and, on the other hand, the filling machines 7 with considerably quicker stop and start capabilities.
  • the flow Fi into the tank 4 may thus only be regulated slowly so as not to disrupt the process 1.
  • the flow F 2 out of the tank 4 may, on the other hand, vary rapidly. From the periodically measured values of the flow Fi and the level L, the flow F 2 is calculated. All regulation of the flow Fi strives to attain the situation that the two flows Fi and F 2 are to be equal.
  • the level L of product in the tank 4 is employed to maintain a desired norm value of the level L.
  • the norm values are calculated and are indicated such that, when the outflow F 2 out of the tank 4 is slight the norm value is high, since the greatest change that can take place is that the outflow F 2 increases and thereby the need for a large buffer volume before the inflow Fi has had time to increase. Conversely, the norm value is indicated such that it is low when the outflow F 2 is high, since the greatest change that can take place in this situation is that the outflow F 2 is reduced.
  • the level norm values should lie between 9-95% of the available volume of the tank 4.
  • the regulation volume constituting the greater part of the volume of the buffer tank, it is thus possible to dimension the buffer tank 4 to a volume which is roughly half of conventionally calculated buffer tanks 4.
  • the measurements of the inflow Fi and the level L of the tank take place periodically, 1-60 times per minute.
  • a suitable periodicity could be 4 times per minute, which would most generally give a sufficient time to be able to regulate the inflow Fi into the tank 4 if the outflow F 2 were suddenly to change.
  • the above-described method of regulating the level in a buffer tank 4 may also be employed for systems with a process 1 downstream which is sensitive to rapid flow changes which may occur upstream in the system.
  • the present invention realises a method of regulating the level of a buffer tank 4 which, while maintaining the quality of the process 1, may be put into effect rapidly and reliably.
  • the method also allows the volume of the buffer tank 4 to be reduced to half of that required by conventional methods.
  • the present invention should not be considered as restricted to that described above and shown on the Drawing, many modifications being conceivable without departing from the scope of the appended Claims.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Control Of Non-Electrical Variables (AREA)
  • Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
  • Basic Packing Technique (AREA)
  • Moulding By Coating Moulds (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
  • Vibration Prevention Devices (AREA)

Abstract

The disclosure relates to a method of regulating the level in a buffer tank (4). By means of conduits (2, 6), the tank (4) is connected to different parts in or peripheral to a process (1). There is an inflow F1 in the incoming conduit (2) and an outflow F2 in the outgoing conduit (6). The method comprises periodic measurements of the inflow F1 and also of the level L of the product which is held in the tank (4). The method also encompasses calculated and indicated level norm values which are indicated such that the level norm value is high when the outflow F2 out of the tank (4) is slight and the level norm value is low when the outflow F2 out of the tank (4) is great.

Description

A METHOD OF REGULATING THE LEVEL IN A BUFFER TANK
TECHNICAL FIELD
The present invention relates to a method of regulating the level in a buffer tank, the tank being connected to conduits for inflow Fi and outflow
F2, respectively, the method comprising periodic measurement and regulation of the inflow Fi into the tank and periodic measurement of the product level L in the tank, as well as indicated level norm values.
BACKGROUND ART
Buffer tanks occur regularly within different process industries for creating a margin between the different parts in the process or between the process proper and, for example, pre-treatment or final packing. Buffer tanks are dimensioned to capable of receiving product if a disruption were to occur between the different parts in or peripheral to the process. The buffer tank is to afford space to be able to regulate one part of, for example, the process if another part in or peripheral to the process were suddenly to stop or change the flow by other means. The buffer tank should be of such dimensions as to accommodate that product volume which is required before regulation could take place. The buffer tank must also retain such a large product volume that there is no risk of it being emptied before regulation can be put into effect. If too small a tank is selected, the product may spill over and thereby be lost, or the tank may be emptied and thereby impede or disrupt the outflow. At the same time, the intention is that the buffer tank should be as little as possible, since large tanks are expensive and bulky.
A simple method of regulating the level in a buffer tank is the so- called on/ off regulation method, which implies that the level is regulated in that the inflow is started or stopped when necessary. This is often an unsuitable method, since it inevitably disrupts the process.
Another common method for regulating the level in a buffer tank is by selecting a tank which is so large that a normal position for product level is situated approximately in the centre of the tank. Then there is space for regulating both upwards and downwards in the tank and the dimensions of the tank are twice the requisite space in order to have time to regulate the process. Apart from the fact that a large tank involves considerable overhead costs and that it requires a large floor space, it also holds a larger quantity of product which runs the risk of being left standing in the buffer tank. Many products in the food industry are today highly specialised and are relatively expensive to produce, which is a further factor guiding the wish to employ as small buffer tanks as possible.
OBJECTS OF THE INVENTION
One object of the present invention is to create a method of regulating the level in a buffer tank which makes for the employment of a tank which is only half as large as those tanks which are normally employed as buffer tanks.
A further object of the present invention is that only the inflow into the tank and the level in the tank are measured. Yet a further object of the present invention is that the method be reliable and dependable such that the process quality is not jeopardised.
SOLUTION
These and other objects have been attained according to the present invention in that the method of the type described by way of introduction has been given the characterizing feature that the level norm values for the tank are disclosed such that the level norm value is high when the outflow F2 from the tank is slight and that the level norm value is low when the outflow F2 from the tank is large. Preferred embodiments of the present invention have further been given the characterizing features as set forth in the appended subclaims.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
One preferred embodiment of the method according to the present invention will now be described in greater detail hereinbelow with reference to the accompanying Drawing, in which:
Fig. 1 shows a flow diagram in which the method according to the present invention may be employed.
DESCRIPTION OF PREFERRED EMBODIMENT
The Drawing shows a process 1 which may be mixing process or the like where great accuracy is required in order to maintain a uniform product quality. From the process 1, a conduit 2 departs with the flow Fj, this flow being periodically measured using a conventional flowmeter 3. The flow Fi must be regulated such that it is altered relatively slowly so as not to disrupt the process 1.
The conduit 2 is connected to a buffer tank 4 in which the flow Fi constitutes the flow Fi into the tank 4. In the tank 4, the level L of the enclosed product is periodically measured with the aid of a conventional level gauge 5. The tank 4 is further connected to a conduit 6 for the outflow F2 out of the tank 4.
The conduit 6 leads the product on to further treatment, such as, for example, packing the product, which may be put into effect in one or more filling machines 7. Reference numeral 7 in Fig. 1 may also, for instance, symbolise a sterilizer. The process 1 is controlled with the aid of a PLC unit 8
(Programmable Logic Controller). The PLC unit 8 periodically reads off a signal 9 from the flowmeter 3. The measurement of the level in the tank 4 also gives an input signal 10 to the PLC unit 8, which this reads off periodically. From the PLC unit 8, one or more signals 11 are emitted to conventional control valves in the process 1 where, in turn, they act on and control the process 1.
In order to maintain a high product quality, the process 1 has an inherent inertia so that a signal for change of the flow of the process 1 may only be implemented such that the process is changed relatively slowly. Aftertreatment, which in Fig. 1 consists of one or more filling machines 7, may start and stop independently of one another almost instantaneously.
The buffer tank 4 thus constitutes the margin between, on the one hand, the process 1 which can only be regulated relatively slowly and, on the other hand, the filling machines 7 with considerably quicker stop and start capabilities. The flow Fi into the tank 4 may thus only be regulated slowly so as not to disrupt the process 1. The flow F2 out of the tank 4 may, on the other hand, vary rapidly. From the periodically measured values of the flow Fi and the level L, the flow F2 is calculated. All regulation of the flow Fi strives to attain the situation that the two flows Fi and F2 are to be equal. The level L of product in the tank 4 is employed to maintain a desired norm value of the level L. The norm values are calculated and are indicated such that, when the outflow F2 out of the tank 4 is slight the norm value is high, since the greatest change that can take place is that the outflow F2 increases and thereby the need for a large buffer volume before the inflow Fi has had time to increase. Conversely, the norm value is indicated such that it is low when the outflow F2 is high, since the greatest change that can take place in this situation is that the outflow F2 is reduced.
The level norm values should lie between 9-95% of the available volume of the tank 4. By the regulation volume constituting the greater part of the volume of the buffer tank, it is thus possible to dimension the buffer tank 4 to a volume which is roughly half of conventionally calculated buffer tanks 4.
The measurements of the inflow Fi and the level L of the tank take place periodically, 1-60 times per minute. A suitable periodicity could be 4 times per minute, which would most generally give a sufficient time to be able to regulate the inflow Fi into the tank 4 if the outflow F2 were suddenly to change.
The above-described method of regulating the level in a buffer tank 4 may also be employed for systems with a process 1 downstream which is sensitive to rapid flow changes which may occur upstream in the system. As will have been apparent from the foregoing description, the present invention realises a method of regulating the level of a buffer tank 4 which, while maintaining the quality of the process 1, may be put into effect rapidly and reliably. The method also allows the volume of the buffer tank 4 to be reduced to half of that required by conventional methods. The present invention should not be considered as restricted to that described above and shown on the Drawing, many modifications being conceivable without departing from the scope of the appended Claims.

Claims

WHAT IS CLAIMED IS:
1. A method of regulating the level in a buffer tank (4), said tank (4) being connected to conduits (2, 6) for inflow Fi and outflow F2, respectively, the method comprising periodic measurement and regulation of the inflow Fi into the tank (4) and periodic measurement of the product level L in the tank (4) and also indicated level norm values, characterized in that the level norm values for the tank (4) are indicated such that the norm value is high when the outflow F2 from the tank (4) is slight and the norm value is low when the outflow F2 from the tank (4) is great.
2. The method as claimed in Claim 1, characterized in that the norm values lie between 5 and 95 % of the volume of the tank (4).
3. The method as claimed in any of the preceding Claims, characterized in that the periodic measurements of the inflow Fi and the level L are made 1-60 times per minute.
PCT/SE1998/000337 1997-02-27 1998-02-25 A method of regulating the level in a buffer tank WO1998038556A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US09/380,152 US6311711B1 (en) 1997-02-27 1998-02-25 Method of regulating the level in a buffer tank
EP98908374A EP0965075B1 (en) 1997-02-27 1998-02-25 A method of regulating the level in a buffer tank
AU66419/98A AU6641998A (en) 1997-02-27 1998-02-25 A method of regulating the level in a buffer tank
DE69814598T DE69814598T2 (en) 1997-02-27 1998-02-25 METHOD FOR CONTROLLING THE LEVEL OF A BUFFER TANK
AT98908374T ATE240543T1 (en) 1997-02-27 1998-02-25 METHOD FOR CONTROLLING THE FILLING LEVEL OF A BUFFER TANK

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9700707A SE508884C2 (en) 1997-02-27 1997-02-27 Method to control the level in a buffer tank
SE9700707-4 1997-02-27

Publications (1)

Publication Number Publication Date
WO1998038556A1 true WO1998038556A1 (en) 1998-09-03

Family

ID=20405956

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1998/000337 WO1998038556A1 (en) 1997-02-27 1998-02-25 A method of regulating the level in a buffer tank

Country Status (9)

Country Link
US (1) US6311711B1 (en)
EP (1) EP0965075B1 (en)
AR (1) AR011900A1 (en)
AT (1) ATE240543T1 (en)
AU (1) AU6641998A (en)
CO (1) CO4770084A1 (en)
DE (1) DE69814598T2 (en)
SE (1) SE508884C2 (en)
WO (1) WO1998038556A1 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7569136B2 (en) 1997-06-24 2009-08-04 Ackerson Michael D Control system method and apparatus for two phase hydroprocessing
US7055611B2 (en) * 2002-01-31 2006-06-06 Weatherford / Lamb, Inc. Plug-dropping container for releasing a plug into a wellbore
US6672384B2 (en) 2002-01-31 2004-01-06 Weatherford/Lamb, Inc. Plug-dropping container for releasing a plug into a wellbore
US6715541B2 (en) 2002-02-21 2004-04-06 Weatherford/Lamb, Inc. Ball dropping assembly
US6776228B2 (en) 2002-02-21 2004-08-17 Weatherford/Lamb, Inc. Ball dropping assembly
TWI225975B (en) * 2003-05-15 2005-01-01 Au Optronics Corp A system for recycling the stripper solution
US9096804B2 (en) 2011-01-19 2015-08-04 P.D. Technology Development, Llc Process for hydroprocessing of non-petroleum feedstocks
DE102021100003A1 (en) * 2021-01-04 2022-07-07 Krones Aktiengesellschaft Process for buffering a sterilized liquid product and filling plant

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3599666A (en) * 1969-04-08 1971-08-17 Ilford Ltd Measuring device
DE2907900A1 (en) * 1979-03-01 1980-09-11 Rudolf Geisler Regulator to control liquid level - has resistive probe coupled to regulator to allow tank discharge to be controlled
US4522228A (en) * 1984-06-12 1985-06-11 Campau Daniel N Fluidic level control system
EP0394869A2 (en) * 1989-04-26 1990-10-31 WindmÀ¶ller & Hölscher Method for controlling the level of a mixture consisting of at least two components of fluid material in a container with an outlet

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6026837A (en) * 1997-05-14 2000-02-22 Taiwan Semiconductor Manufacturing Company, Ltd. Automated chemical drain system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3599666A (en) * 1969-04-08 1971-08-17 Ilford Ltd Measuring device
DE2907900A1 (en) * 1979-03-01 1980-09-11 Rudolf Geisler Regulator to control liquid level - has resistive probe coupled to regulator to allow tank discharge to be controlled
US4522228A (en) * 1984-06-12 1985-06-11 Campau Daniel N Fluidic level control system
EP0394869A2 (en) * 1989-04-26 1990-10-31 WindmÀ¶ller & Hölscher Method for controlling the level of a mixture consisting of at least two components of fluid material in a container with an outlet

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Vol. 14, No. 272, (P-1060); & JP,A,02 079 108 (NORITZ CORP) 19 March 1990. *
PATENT ABSTRACTS OF JAPAN, Vol. 8, No. 58, (P-261); & JP,A,58 207 114 (YOKOGAWA DENKI SEISAKUSHO K.K.) 2 December 1983. *

Also Published As

Publication number Publication date
AR011900A1 (en) 2000-09-13
CO4770084A1 (en) 1999-04-30
ATE240543T1 (en) 2003-05-15
SE9700707D0 (en) 1997-02-27
DE69814598D1 (en) 2003-06-18
US6311711B1 (en) 2001-11-06
EP0965075A1 (en) 1999-12-22
SE9700707L (en) 1998-08-28
EP0965075B1 (en) 2003-05-14
DE69814598T2 (en) 2004-04-29
SE508884C2 (en) 1998-11-16
AU6641998A (en) 1998-09-18

Similar Documents

Publication Publication Date Title
US6311711B1 (en) Method of regulating the level in a buffer tank
US6598617B2 (en) Cascaded variable bias feedforward and feedback flow and level control system
CA2036622A1 (en) Method and apparatus for beverage blending and proportioning
US5096120A (en) Process and apparatus to guide a spray material to a plurality of spraying statins
CN1202616A (en) Fluid flow rate measuring and controlling device and method
FI59494C (en) FOERFARANDE OCH ANORDNING FOER PROCESSREGLERING
ES2180334T3 (en) REGULATION DEVICE FOR THE REGULATION OF A JOURNEY WITH VARIOUS COVERED VARIABLES OF REGULATION.
JP4256684B2 (en) Gas supply method
KR19990087058A (en) A method of supplying gas to the chamber and a method of controlling the content of a given component in the chamber atmosphere
CA2469641A1 (en) Feed opening adjustment of segments for continuous casting systems
US3981767A (en) Apparatus and method for controlling the stock flow to a paper machine headbox
KR950702879A (en) Arrangement designed to be a part of an equipment for cleaning different objects in a food processing plant
CN114879482B (en) Double-valve switching control method and device for heating power station, control equipment and storage medium
EP0187484A1 (en) Method and apparatus for controlling temperature of a liquid
US4257438A (en) Bulk catalyst proportioner
SU613299A1 (en) Device for regulating fluid flow parameters
EP0129287B1 (en) Control system
EP0775339A1 (en) Current-to-pressure transducer with selectable, adjustable input filter
US20030105536A1 (en) Open and closed loop flow control system and method
JPH0772934A (en) In-line mixing controller
SU429850A1 (en) AUTOMATIC ADJUSTMENT SPOSES FILING SUSPENSION TO AUGER CENTER.FUG
KR960702634A (en) REGULATING DEVICE
JPS63214599A (en) Control device for liquefied natural gas gasifying facility
SU666519A1 (en) Device for regulating loose material rate-of-flow
SU1232682A1 (en) Method of automatic control for process of sterilizing multiple-component nutrient medium

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH GM GW HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1998908374

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 09380152

Country of ref document: US

WWP Wipo information: published in national office

Ref document number: 1998908374

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1998537573

Format of ref document f/p: F

WWG Wipo information: grant in national office

Ref document number: 1998908374

Country of ref document: EP