WO1994010556A1 - Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters - Google Patents

Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters Download PDF

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Publication number
WO1994010556A1
WO1994010556A1 PCT/HU1993/000060 HU9300060W WO9410556A1 WO 1994010556 A1 WO1994010556 A1 WO 1994010556A1 HU 9300060 W HU9300060 W HU 9300060W WO 9410556 A1 WO9410556 A1 WO 9410556A1
Authority
WO
WIPO (PCT)
Prior art keywords
detecting head
capacitor plate
indicating
water
detecting
Prior art date
Application number
PCT/HU1993/000060
Other languages
French (fr)
Inventor
Ferenc Puhl
Zoltán PAPP
Ferenc Puhl, Jr.
Original Assignee
Ferenc Puhl
Papp Zoltan
Puhl Ferenc Jr
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 Ferenc Puhl, Papp Zoltan, Puhl Ferenc Jr filed Critical Ferenc Puhl
Priority to AU53441/94A priority Critical patent/AU5344194A/en
Publication of WO1994010556A1 publication Critical patent/WO1994010556A1/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/22—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
    • G01N27/221—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance by investigating the dielectric properties
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/18—Water
    • G01N33/1826—Water organic contamination in water
    • G01N33/1833—Oil in water
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/24—Earth materials
    • G01N33/241—Earth materials for hydrocarbon content

Definitions

  • the invention relates to an apparatus for detecting and indicating the presence of crude oil derivates contained in water, especially soil or ground waters.
  • the apparatus comprises a detecting head capable of distinguishing oil derivates from water, and a means for indicating the detected and measured signals of the detecting head.
  • the apparatus is readily applicable for detecting, indicating and continuously monitoring the presence, and if present, the thickness of layers of oil derivates in or on the surface of bodies of water.
  • Sensing and measuring the water level and the level of other liquids in the soil or in a tank is quite frequently an important technical task.
  • a more significant problem is however, to detect and identify what different kind of fluid, e.g. a film of some oil derivate is floating on the surface of a body of soil or ground water.
  • the increase of soil pollution is frequently detected and measured by testing the quality of the ground water, for which purpose complicated testing methods using wells or boreholes are applied.
  • a main object of the present invention is to provide an improved and novel apparatus by which, as a general approach, the increase of soil contamination can be detected and the more and more dominating need for its determination at regular intervalls can be met.
  • a more particular object of the present invention is to provide an apparatus, by which the presence and the layer thickness of crude oil derivates appearing in the soil can be rapidly and easily sensed, detected and measured at high level of accuracy.
  • the invention is based on and makes use of the recognition that the relative permittivity (er) of the air and that of fluids are different.
  • air and fluids can be well distinguished from one another by measuring said physical parameter.
  • another particular object of the present invention is to provide, in an apparatus for detecting and indicating the presence of crude oil derivates contained in water, especially soil or ground waters, a detecting head capable of electrically sensing and measuring the relative permittivity of air, oil and water.
  • the present invention provides a novel apparatus comprising a detecting head capable of distinguishing oil derivates from water by making use of the different values of their diffe ⁇ rent relative permittivity, and a means for indicating the detected and measured signals of said detecting head.
  • the apparatus according to the invention is readily applicable for rapid detecting, indicating and also for continuously monitoring the presence of oil derivates contained in water, especially soil or ground waters.
  • the detecting head essen ⁇ tially consists of a power supply cable that is introduced into a test head housing and connected via a power supply filter to an AC generator.
  • the AC generator is linked via a separating capacitor to at least one first capacitor plate.
  • the detecting head further comprises at least one second capacitor plate that is arranged in a distanced parallel relation to, preferably around the at least one first capa ⁇ citor plate, and is connected via a rectifier unit and a low-pass filter to an output signal cable leading to the preferably remotely located means for indicating the detec ⁇ ted and measured signals of the detecting head.
  • the detecting head is arranged at a lower end of a suspending cable that comprises, preferably as integral parts thereof, also the power supply cable and the output signal cable.
  • the detecting head further comprises a cover plate made of electrically insulating material.
  • the cover plate separates, positiones and carries, via spacers, the at least one first and second capacitor plates at their pre-deter ined locations with respect to each other and the detecting head housing.
  • the at least one first capacitor plate and the at least one second capacitor plate are arranged with respect to each other in a way that they form at least one pair of concentrically spaced cylindrical members.
  • said at least one pair of concentrically spaced cylindrical members forming the at least one first capacitor plate and the at least one second capacitor plate is arranged below a bottom part, particularly below the cover plate of the detecting head housing.
  • the detecting head of the apparatus comprises an appropriately designed capacitor which yields different capacity values when immersed in fluids of different relative permittivities.
  • one capa ⁇ citor plate of the capacitor When one capa ⁇ citor plate of the capacitor is supplied with an AC voltage, and the signal appearing on the other capacitor plate is rectified, the DC voltage obtained is characteristic of the kind of fluid that fills in the space between said capacitor plates.
  • the detecting head When the detecting head is connected to an indicator device known per se, the indicated signal will clearly show whether the the detecting head is immersed in air, oil or water. By lowering or raising the position of the detecting head, the exact position of the oil derivate or the water level and the thickness of the oil layer can be determined.
  • the detecting head and the indicator device comprising the present invention is suitable for the high accuracy, automatic determination of the thickness and related depth of crude oil derivate (layers) floating on the surface of water in a well, a suitable borehole or a tank.
  • the apparatus of the invention can be used primarily in the area of environment protection activities (damage- taking, decontamination, checking and monitoring technologies) , especially in association with the CH pollution of soil and water.
  • Embodiments of the apparatus can be made suitable also for continuous and automatic monitoring and for providing an immediate alarm signal if any technical prob ⁇ lem (for example leakage) of a potential contamination source (e.g. a petrol tank) to be monitored occures.
  • a potential contamination source e.g. a petrol tank
  • Fig. 1 shows the longitudinal sectional view of a detecting head
  • a power supply cable 3 is introduced into a test head housing 1 and it is connected via a power supply filter 4 to an AC generator 5.
  • the AC generator 5 is linked via a separating capacitor 6 to a first capacitor plate 7.
  • the detecting head further comprises a second capacitor plate 8 which is arranged in a distanced parallel relation around the first capacitor plate 7.
  • the second capacitor plate 8 is connected via a rectifier unit 10 and a low-pass filter 11 to an output signal cable 13 which leads to a remotely located means, known per se, for indicating the detected and measured signals of the detecting head.
  • the detecting head is arranged at and mechanically connected to the lower end of a suspending cable 14.
  • the suspending cable 14 comprises as integral parts both the power supply cable 3 and the output signal cable 13.
  • the detecting head can be lowered and immersed into the fluid, especially soil or ground water to be detected and/or continuously monitored, by moving, especially lowering the suspending cable 14.
  • the detecting head comprises a cover plate 12 made of electrically insulating material.
  • the cover plate 12 separates and carries, via spacers 9, the first and second capacitor plates 7, 8 at their pre-determined locations with respect to each other and the detecting head housing 1.
  • the first capacitor plate 7 and the second capacitor plate 8 are arranged with respect to each other in a manner that they form a pair of concentrically spaced cylindrical members. It seems to be of importance to note that within the scope of the invention also more than one pairs of capacitor plates can be used.
  • such pairs of capacitor plates can be arranged by forming a sequence of capacitors located below the bottom part, particularly below the cover plate 12 of the detecting head housing 1.
  • a perforated protecting ring 2 is arranged around the one pair of first and second capacitor plates 7, 8.
  • the protecting ring 2 is secured to the housing 1 and protects the condenser plates 7,8 from mechanical damage while it allows as a result of its design, for the free flow of the fluid to be detected to the space between said capacitor plates 7,8.
  • the detecting head of the apparatus receives power required for operation via the smoothing power supply filter 4 and through the power supply cable 3 from a suitable outside source.
  • the signal of the preferably CMOS NOR gates high frequency AC generator 5 is fed through the DC voltage separating capacitor 6 to the first capacitor plate 7.
  • the AC voltage appearing at the second capacitor plate 8 depends on the dielectric characteristics of the fluid in which the capacitor plates 7,8 of the detecting head are immersed. This AC voltage is supplied to the rectifier unit 10.
  • the rectified signal is conveyed to any suitable remote indicator device (not shown) through the low-pass filter 11 that prevents the transmission of high frequencies, and via the output signal cable 13.
  • the output voltage detected and measured in air as dielectric fluid between the capacitor plates 7,8 can be considered as a reference signal, or it can be used for indicating breakdown or failure in the operation of the apparatus.
  • the output voltage will be about twice of that of the reference signal, and for water, the output voltage will reach its maximum value.
  • One of the most popular and advantageous fields of application for the apparatus according to the invention is the measuring the thickness of an oil film floating on the surface of a water body, preferably of a soil or ground water.
  • the lowering movement of the suspending cable 14. can be sensed and detected e.g. by a measuring disk known per se, which may be of the kind that emits a pulse for each millimeter.
  • the pulse counter is reset to zero.
  • the pulses are counted until the detecting head senses that the water surface is reached. At this stage, the counting of pulses is stopped, and the number of the pulses counted is indicated and stored until the next period of operation.
  • the detector may be used as a monitoring device located at a site of possible or an expected contamination.
  • a suitable alarm signal is produced when the indicating head of the apparatus senses that oil contamination appeared.

Abstract

In an apparatus comprising a detecting head capable of distinguishing oil derivates from water and means for indicating the detected and measured signals of said detecting head, a power supply cable (3) is introduced into a test head housing (1) and connected via a power supply filter (4) to an AC generator (5). The AC generator (5) is linked via a separating capacitor (6) to at least one first capacitor plate (7). The detecting head further comprises at least one second capacitor plate (8) that is arranged in a distanced parallel relation to the at least one first capacitor plate (7). The at least one second capacitor plate (8) is connected via a rectifier unit (10) and a low-pass filter (11) to an output signal cable (13) leading to the preferably remotely located means for indicating the detected and measured signals of the detecting head.

Description

Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters
TECHNICAL FIELD
The invention relates to an apparatus for detecting and indicating the presence of crude oil derivates contained in water, especially soil or ground waters. The apparatus comprises a detecting head capable of distinguishing oil derivates from water, and a means for indicating the detected and measured signals of the detecting head. The apparatus is readily applicable for detecting, indicating and continuously monitoring the presence, and if present, the thickness of layers of oil derivates in or on the surface of bodies of water.
BACKGROUND ART
Sensing and measuring the water level and the level of other liquids in the soil or in a tank is quite frequently an important technical task. A more significant problem is however, to detect and identify what different kind of fluid, e.g. a film of some oil derivate is floating on the surface of a body of soil or ground water. The increase of soil pollution is frequently detected and measured by testing the quality of the ground water, for which purpose complicated testing methods using wells or boreholes are applied.
Known equipments for detecting and testing the quality of environmental waters, especially that of sewage water, are not suitable for the rapid sensing and continuous monitoring of the presence, position and volume of oil derivates appearing in or on the surface of bodies of water, particularly of soil or ground water.
DISCLOSURE OF INVENTION
A main object of the present invention is to provide an improved and novel apparatus by which, as a general approach, the increase of soil contamination can be detected and the more and more dominating need for its determination at regular intervalls can be met. A more particular object of the present invention is to provide an apparatus, by which the presence and the layer thickness of crude oil derivates appearing in the soil can be rapidly and easily sensed, detected and measured at high level of accuracy.
The invention is based on and makes use of the recognition that the relative permittivity (er) of the air and that of fluids are different. Thus, air and fluids can be well distinguished from one another by measuring said physical parameter. The relative permittivity of air is er = 1, that of crude oil which does not include dipoles, is between values of er - 2-3, while alcohol, glycerine and water that include a dipole, show values of relative permittivity that are within a range of er = 20-80. As a consequence, another particular object of the present invention is to provide, in an apparatus for detecting and indicating the presence of crude oil derivates contained in water, especially soil or ground waters, a detecting head capable of electrically sensing and measuring the relative permittivity of air, oil and water.
Based on the above and other recognitions, the present invention provides a novel apparatus comprising a detecting head capable of distinguishing oil derivates from water by making use of the different values of their diffe¬ rent relative permittivity, and a means for indicating the detected and measured signals of said detecting head. The apparatus according to the invention is readily applicable for rapid detecting, indicating and also for continuously monitoring the presence of oil derivates contained in water, especially soil or ground waters. The detecting head essen¬ tially consists of a power supply cable that is introduced into a test head housing and connected via a power supply filter to an AC generator. The AC generator is linked via a separating capacitor to at least one first capacitor plate. The detecting head further comprises at least one second capacitor plate that is arranged in a distanced parallel relation to, preferably around the at least one first capa¬ citor plate, and is connected via a rectifier unit and a low-pass filter to an output signal cable leading to the preferably remotely located means for indicating the detec¬ ted and measured signals of the detecting head.
In preferred embodiments of the invention the detecting head is arranged at a lower end of a suspending cable that comprises, preferably as integral parts thereof, also the power supply cable and the output signal cable. By this provision, the detecting head can be lowered and immersed into the fluid, especially ground water to be detected and/or continuously monitored.
In other preferred embodiments, the detecting head further comprises a cover plate made of electrically insulating material. The cover plate separates, positiones and carries, via spacers, the at least one first and second capacitor plates at their pre-deter ined locations with respect to each other and the detecting head housing.
In further preferred embodiments of the invention 94/10556
the at least one first capacitor plate and the at least one second capacitor plate are arranged with respect to each other in a way that they form at least one pair of concentrically spaced cylindrical members.
Finally, in still further preferred embodiments of the present invention said at least one pair of concentrically spaced cylindrical members forming the at least one first capacitor plate and the at least one second capacitor plate is arranged below a bottom part, particularly below the cover plate of the detecting head housing.
As clearly follows from the above presentation, the detecting head of the apparatus according to the present invention comprises an appropriately designed capacitor which yields different capacity values when immersed in fluids of different relative permittivities. When one capa¬ citor plate of the capacitor is supplied with an AC voltage, and the signal appearing on the other capacitor plate is rectified, the DC voltage obtained is characteristic of the kind of fluid that fills in the space between said capacitor plates. When the detecting head is connected to an indicator device known per se, the indicated signal will clearly show whether the the detecting head is immersed in air, oil or water. By lowering or raising the position of the detecting head, the exact position of the oil derivate or the water level and the thickness of the oil layer can be determined.
Consequently the detecting head and the indicator device comprising the present invention is suitable for the high accuracy, automatic determination of the thickness and related depth of crude oil derivate (layers) floating on the surface of water in a well, a suitable borehole or a tank.
The apparatus of the invention can be used primarily in the area of environment protection activities (damage- taking, decontamination, checking and monitoring technologies) , especially in association with the CH pollution of soil and water. 1
Embodiments of the apparatus can be made suitable also for continuous and automatic monitoring and for providing an immediate alarm signal if any technical prob¬ lem (for example leakage) of a potential contamination source (e.g. a petrol tank) to be monitored occures.
BRIEF DESCRIPTION OF THE DRAWING
Hereinafter, the invention will be described on a preferred embodiment shown, by way of example only, in the attached single drawing figure wherein
Fig. 1 shows the longitudinal sectional view of a detecting head
DETAILED. DESCRIPTION OF A PREFERRED EMBODIMENT
As shown in Fig. 1 of the attached drawing, a power supply cable 3 is introduced into a test head housing 1 and it is connected via a power supply filter 4 to an AC generator 5. The AC generator 5 is linked via a separating capacitor 6 to a first capacitor plate 7. The detecting head further comprises a second capacitor plate 8 which is arranged in a distanced parallel relation around the first capacitor plate 7. The second capacitor plate 8 is connected via a rectifier unit 10 and a low-pass filter 11 to an output signal cable 13 which leads to a remotely located means, known per se, for indicating the detected and measured signals of the detecting head. The detecting head is arranged at and mechanically connected to the lower end of a suspending cable 14. The suspending cable 14 comprises as integral parts both the power supply cable 3 and the output signal cable 13. The detecting head can be lowered and immersed into the fluid, especially soil or ground water to be detected and/or continuously monitored, by moving, especially lowering the suspending cable 14. The detecting head comprises a cover plate 12 made of electrically insulating material. The cover plate 12 separates and carries, via spacers 9, the first and second capacitor plates 7, 8 at their pre-determined locations with respect to each other and the detecting head housing 1. In this preferred embodiment of the invention, the first capacitor plate 7 and the second capacitor plate 8 are arranged with respect to each other in a manner that they form a pair of concentrically spaced cylindrical members. It seems to be of importance to note that within the scope of the invention also more than one pairs of capacitor plates can be used. In certain preferred embodiments of the invention such pairs of capacitor plates can be arranged by forming a sequence of capacitors located below the bottom part, particularly below the cover plate 12 of the detecting head housing 1. In the embodiment shown in Fig.l by way of example only, a perforated protecting ring 2 is arranged around the one pair of first and second capacitor plates 7, 8. The protecting ring 2 is secured to the housing 1 and protects the condenser plates 7,8 from mechanical damage while it allows as a result of its design, for the free flow of the fluid to be detected to the space between said capacitor plates 7,8. When in operation, the detecting head of the apparatus according to the present invention receives power required for operation via the smoothing power supply filter 4 and through the power supply cable 3 from a suitable outside source.
The signal of the preferably CMOS NOR gates high frequency AC generator 5 is fed through the DC voltage separating capacitor 6 to the first capacitor plate 7. The AC voltage appearing at the second capacitor plate 8 depends on the dielectric characteristics of the fluid in which the capacitor plates 7,8 of the detecting head are immersed. This AC voltage is supplied to the rectifier unit 10. The rectified signal is conveyed to any suitable remote indicator device (not shown) through the low-pass filter 11 that prevents the transmission of high frequencies, and via the output signal cable 13.
The output voltage detected and measured in air as dielectric fluid between the capacitor plates 7,8 can be considered as a reference signal, or it can be used for indicating breakdown or failure in the operation of the apparatus. For oil as dielectric fluid, the output voltage will be about twice of that of the reference signal, and for water, the output voltage will reach its maximum value.
PREFERRED FIELDS OF APPLICATION
One of the most popular and advantageous fields of application for the apparatus according to the invention is the measuring the thickness of an oil film floating on the surface of a water body, preferably of a soil or ground water. The lowering movement of the suspending cable 14. can be sensed and detected e.g. by a measuring disk known per se, which may be of the kind that emits a pulse for each millimeter. When reaching the upper surface boundary of the oil layer or film is sensed by the detecting head, the pulse counter is reset to zero. When continuing with lowering the suspending cable, the pulses are counted until the detecting head senses that the water surface is reached. At this stage, the counting of pulses is stopped, and the number of the pulses counted is indicated and stored until the next period of operation.
In another application the detector may be used as a monitoring device located at a site of possible or an expected contamination. In such applications, a suitable alarm signal is produced when the indicating head of the apparatus senses that oil contamination appeared. LIST OF REFERENCE SIGNS
1 housing
2 protecting ring
3 power supply cable
4 power supply filter
5 AC generator
6 separating capacitor
7 capacitor plate
8 capacitor plate
9 spacer
10 rectifier unit
11 low-pass filter
12 cover plate
13 output signal cable
14 suspending cable

Claims

1. In an apparatus comprising a detecting head capable of distinguishing oil derivates from water and a means for indicating the detected and measured signals of said detecting head, said apparatus being applicable for detecting, indicating and continuously monitoring the presence of oil derivates contained in water, especially soil or ground waters, the detecting head is characterized in a power supply cable (3) being introduced into a test head housing (1) and connected via a power supply filter (4) to an AC generator (5) , said AC generator (5) being linked via a separating capacitor (6) to at least one first capacitor plate (7) , said detecting head further comprising at least one second capacitor plate (8) arranged in a distanced parallel relation to, preferably around said at least one first capacitor plate (7) , and said at least one second capacitor plate (8) being connected via a rectifier unit (10) and a low-pass filter (11) to an output signal cable (13) leading to said preferably remotely located means for indicating the detected and measured signals of said detecting head.
2. An apparatus as claimed in Claim 1, characterized in said detecting head being arranged at and mechanically connected to the lower end of a suspending cable (14) , said suspending cable (14) comprising, preferably as integral parts thereof, said power supply cable (3) and also said output signal cable (13) , so that said detecting head can be lowered and immersed into the fluid, especially soil or ground water to be detected and/or continuously monitored, by means of said suspending cable (14).
3. An apparatus as claimed in Claim 1 or 2 , characterized in said detecting head further comprising a cover plate (12) made of electrically insulating material, said cover plate (12) separating, positioning and carrying, via spacers (9) , said at least one first and second capaci¬ tor plates (7, 8) at their pre-determined locations with respect to each other and said detecting head housing (1) .
4. An apparatus as claimed in Claim 1 or 2 , characterized in that said at least one first capacitor plate (7) and said at least one second capacitor plate (8) are arranged with respect to each other in a manner that they form at least one pair of concentrically spaced cylind¬ rical members.
5. An apparatus as claimed in Claim 4, characterized in that said at least one pair of concentrically spaced cylindrical members forming said at least one first capacitor plate (7) and said at least one second capacitor plate (8) is arranged below a bottom part, particularly below the cover plate (12) of the housing (1) of said detecting head
PCT/HU1993/000060 1992-10-29 1993-10-21 Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters WO1994010556A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU53441/94A AU5344194A (en) 1992-10-29 1993-10-21 Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
HUP9203392 1992-10-29
HU9203392A HUT67732A (en) 1992-10-29 1992-10-29 Detector for disgriminating derivatives of petroleum and water

Publications (1)

Publication Number Publication Date
WO1994010556A1 true WO1994010556A1 (en) 1994-05-11

Family

ID=10982484

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/HU1993/000060 WO1994010556A1 (en) 1992-10-29 1993-10-21 Apparatus for detecting and indicating the presence of oil derivates contained in water, especially soil or ground waters

Country Status (3)

Country Link
AU (1) AU5344194A (en)
HU (1) HUT67732A (en)
WO (1) WO1994010556A1 (en)

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
SOVIET INVENTIONS ILLUSTRATED, Section E1: Electrical, week 8507, issued 27 March 1985, Derwent Publications Ltd., London S03; & SU,A,1 103 137 (SEVAST EQUIPT INST). *
SOVIET INVENTIONS ILLUSTRATED, Section E1: Electrical, week 8648, issued 14 January 1987, Derwent Publications Ltd., London S03; & SU,A,1 226 251 (SEVAST INSTR. INSZ). *

Also Published As

Publication number Publication date
HUT67732A (en) 1995-04-28
AU5344194A (en) 1994-05-24
HU9203392D0 (en) 1993-03-01

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