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US20020060020A1 - On-line deposition monitor - Google Patents

On-line deposition monitor Download PDF

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Publication number
US20020060020A1
US20020060020A1 US09/902,248 US90224801A US2002060020A1 US 20020060020 A1 US20020060020 A1 US 20020060020A1 US 90224801 A US90224801 A US 90224801A US 2002060020 A1 US2002060020 A1 US 2002060020A1
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US
United States
Prior art keywords
organic
internal reflectance
process water
reflectance element
infrared radiation
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.)
Abandoned
Application number
US09/902,248
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English (en)
Inventor
Richard Irwin
Geary Yee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hercules LLC
Original Assignee
Hercules LLC
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 Hercules LLC filed Critical Hercules LLC
Priority to US09/902,248 priority Critical patent/US20020060020A1/en
Priority to AU2001271988A priority patent/AU2001271988A1/en
Priority to PCT/US2001/021920 priority patent/WO2002004941A2/fr
Assigned to HERCULES INCORPORATED reassignment HERCULES INCORPORATED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: IRWIN, RICHARD M., YEE, GEARY G.
Publication of US20020060020A1 publication Critical patent/US20020060020A1/en
Abandoned legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N17/00—Investigating resistance of materials to the weather, to corrosion, or to light
    • G01N17/008—Monitoring fouling
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/55—Specular reflectivity
    • G01N21/552—Attenuated total reflection
    • 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
    • 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
    • G01N33/186—Water using one or more living organisms, e.g. a fish
    • G01N33/1866—Water using one or more living organisms, e.g. a fish using microorganisms
    • 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
    • G01N33/36—Textiles

Definitions

  • the present invention relates to a method and apparatus using spectroscopic analysis for the on-line monitoring of biological and chemical deposition from paper process water. More particularly, the present invention relates to methods and apparatuses using attenuated total reflectance spectroscopy for qualitatively and quantitatively determining contaminants depositing from paper process water, as well as for determining the rates of deposition and growth of such contaminants.
  • biofilms bacterial films
  • slime protective exopolysaccharides
  • inorganic contaminants such as calcium carbonate (“fillers”) and organic contaminants often deposit on such surfaces.
  • these organic contaminants typically include pitch (e.g., resins from wood) and stickies (e.g., glues, adhesives, tape, and wax particles).
  • Such methods are limited to traditional analysis, such as microscopy, which are laborious, subjective, and do not reliably reveal the dynamics (e.g., effects of pH, system additives, consistency) of the variations in process water parameters as the sampling frequency cannot typically be greater than one sample per hour, whereas the actual time constants of the variations are a matter of a few minutes.
  • Sophisticated analyses to reveal deposit composition are limited to relatively thick deposits and are generally very difficult owing to alteration and aging of surface layers during handling.
  • Spectroscopic means have been used generally in analyzing biofilm growth or chemical contaminants dissolved or dispersed in fluid media.
  • D.E. Nivens, et al. “Continuous Nondestructive Monitoring of Microbial Biofilms: A Review of Analytical Techniques”, Journal of Industrial Microbiology, (1995) 15: 263-276 (“Nivens”); Tornberg, J. et al., “On-line Measurement Of Organic Substances In Paper Machine Wet End Water Using IR Spectroscopy”, Paper and Timber, (1993) 75, 4: 228-232 (“Tornberg”).
  • such techniques would appear to be unsuitable for use in on-line analysis of paper machine process water due to the unique characteristics of such process water.
  • Attenuated total reflection (ATR) spectroscopy a sampling technique used to examine aqueous environments near the surface of a special substratum called the internal reflection element (IRE), permits analysis of a base layer (approximately 1 micron) of biofilms and only provides an average picture of the chemistry transpiring over the entire area exposed to the aqueous environment.
  • ATR produces spectra containing vibrational information from all the molecules within the evanescent-wave region (region into which infrared radiation penetrates) resulting in data which is coincidental and convoluted. Further, determinations such as distinguishing dead biomass from living biomass from a single spectrum cannot be done.
  • IR spectroscopy is not suitable for use in analyzing paper machine process water.
  • germanium as an IRE is not acceptable in an ATR unit for use with paper machines processes as such this element corrodes in paper process waters.
  • the depth of penetration of the infrared radiation does not allow for meaningful analysis of the types of growths and deposits found in paper machine process whitewater, which are typically several centimeters in thickness.
  • the present invention involves the use of infrared spectroscopy, particularly ATR spectroscopy, wherein electromagnetic radiation is absorbed by atoms or molecules to qualitatively and quantitatively study biofilms and chemical contaminants (e.g., cellulose, carbonates, lignins, pitch, stickies) present in paper process water.
  • the interaction of the radiation with the atoms or molecules causes redirection of the radiation and/or transitions between the energy levels of the atoms or molecules.
  • Absorption occurs when a transition from a lower level to a higher level occurs with a transfer of energy from the radiation field to the atom or molecule.
  • atoms or molecules absorb radiation, the incoming energy excites a quantized structure to a higher energy level.
  • the type of excitation depends on the wavelength of the radiation. For example, in the present invention, vibrations are excited by infrared radiation.
  • an absorption spectrum is realized, which is the absorption of radiation as a function of wavelength.
  • the spectrum of an atom or molecule depends on its energy level structure, and absorption spectra are useful for identifying compounds.
  • each organic and inorganic contaminant has a characteristic absorption spectrum in which peaks due to different functional groups (e.g., hydroxyl) can be identified.
  • an absorption spectrum or absorption values at particular wavelengths are measured through the use of ATR spectrometry in which a beam of infrared light is transmitted through a crystal having the sample to be analyzed adsorbed thereto. Once the beam hits the surface of the sample it measures the active groups on or near the surface of the sample.
  • ATR spectroscopy which uses the total internal reflection technique, is typically used in the mid-infrared region of the visible spectrum where absorptions due to molecular vibrations permit the analysis of contaminants in the present invention at the interface of an IRE present in the ATR unit. While the absorptions at each light reflection with the IRE are small, the attenuation of the incident infrared radiation can be increased by multiple reflections along the length of the IRE. The incident radiation is of sufficient intensity so that the light emerging from the IRE crystal after multiple reflections can be measured with good precision.
  • the present invention involves the use of such an ATR technique to sense both the composition and rate of deposition of contaminant substances onto paper machine surfaces from aqueous process fluids.
  • Process water to be analyzed flows from paper machine process water source 102 into an input conduit 104 , as indicated by arrow 103 .
  • the process water then flows from input conduit 104 into fluid chamber 106 , in fluid communication therewith, where it then flows longitudinally. Over time, contaminants 114 which are present in the water will adsorb onto the upper surface of IRE 112 within fluid chamber 106 .
  • the water then exits the ATR flow cell 100 as indicated by arrow 107 through an output conduit 108 which is in fluid communication with input conduit 104 and fluid flow chamber 106 .
  • the process water After exiting ATR flow cell 100 , the process water then re-enters process water source 102 or is discarded.
  • the paper machine process water source which may be analyzed by the present invention may be any water source found in the papermaking industry, such as whitewater. Elements of ATR flow cell 100 of the present invention are selected such that they do not corrode under conditions associated with such process water.
  • the top portion of flow cell 100 forms a cover over the IRE crystal 112 and is made of clear plastic, which facilitates access to IRE 112 for cleaning.
  • An O-ring and screws are respectively used to seal and secure the cover to the flow cell 100 .
  • a flow channel is machined into the cover which is designed so that the complete volume of fluid flow chamber 106 is swept at nearly the same flow rate and fabricated such that sharp edges and burrs are minimized which may trap fines, paper fibers, and debris.
  • An infrared radiation source 110 from a broadband or discreet light source, provides radiation to an IRE 112 , as indicated by arrow 111 in FIG. 1.
  • the IRE may be any material that is suitable for use in the present invention so long as the material is non-corrosive under paper machine process water conditions and is non-reactive to components of paper process water streams.
  • An IRE suitable for use in the present invention must be capable of withstanding paper machine process water conditions (e.g., be insoluble in water), must be capable of reflecting internally, and must be transparent to the infrared radiation. The material must be transparent because the IR radiation must reach the detector 116 .
  • an IRE of zinc selenide crystal is suitable for use in the present invention while germanium is not.
  • an active area on the IRE which is relatively large, for example 3.8 cm 2 , has been found suitable for permitting the adsorption of contaminants from paper process streams thereon.
  • the IRE may be of any suitable crystalline geometry.
  • a standing wave of radiation penetrates out from IRE 112 into the process water, and the intensity of the radiation decays exponentially with its distance from the IRE 112 .
  • the decaying wave known as an evanescent wave, consists of the same frequencies as the reflected light, and may be absorbed by the contaminant molecules near the outer surface of the IRE.
  • the radiation is absorbed by a molecule of a contaminant when the energy of the radiation is equal to that required to promote the molecule to an excited vibrational state.
  • absorption occurs only at discrete frequencies when a molecule is exposed to a continuum of IR radiation and the amount of radiation absorbed is proportional to the number of molecules present. This frequency-dependent absorption results in a unique absorbence pattern (spectrum) that is defined by the structure of the molecule.
  • complex systems such as biofilms have a spectrum that is the sum of the spectral signature of each biomolecule in the sample.
  • the frequency or wavenumber at which a molecule absorbs radiation is mainly determined by specific groups of atoms (functional groups) within the molecule.
  • the individual wavenumber range at which a specific group of atoms absorbs radiation is referred to as the characteristic frequency.
  • Known characteristic frequencies allow the identification of IR absorbence bands which permit identification of differences in molecular structure of the contaminants and which permit the contaminants to be quantified as well.
  • the correlation of functional groups and wavelengths of absorption bands is known in the art (e.g., Infrared and Raman Spectroscopy, Grasselli, J. G., Brame, E. G., Ed., Marcel Dekker (1977); Siverstein, Bassler and Morrill, Spectrometric Identification of Organic Compounds ).
  • the attenuated light which is then measured in a conventional manner by a detector, such as a filter, interferometer, or array-based measuring device.
  • the detector is part of an optical spectrometer 116 for measuring wavelengths of light emitted from IRE 112 .
  • the radiation is monitored by spectrometer 116 at particular frequencies which are chosen to specifically correspond to the frequency values of known molecular absorptions present in the paper process water deposit contaminants of interest. For example, very strong absorbence signals from carbonate between 1600 and 1300 cm ⁇ 1 , commonly present in paper process waters, must be suppressed to allow observation of weaker signals from other components of interest at nearby frequencies.
  • Spectrometer 116 may be, for example, a Fourier transform-infrared (FTIR) spectrometer which uses an interferometer to measure all light frequencies simultaneously with the light signal modulated over time.
  • An FTIR is desirably used in the present invention because it offers increased analysis speed, improved signal to noise ratios, better wavenumber accuracy, and greater signal throughput at similar resolution, as compared to other known detectors.
  • Such instruments typically incorporating radiation beams can be switched with reflective optics and facilitate measurement of the spectra of deposits on IREs in different flow cells, exposed to different treatments, thereby permitting use of the present invention in experimental designs, such as to test the efficacy of various biocidal agents on the growth of biofilms in paper process water.
  • spectrometer 116 outputs spectral data corresponding to the absorption of light by molecules present in the contaminants to a signal processing algorithm 118 which is used for calculating and reporting changes in absorption over time.
  • the data obtained thereby are output to controllers 120 for regulation of chemical levels (e.g., biocidal levels) present in paper process water source 102 in order to effectively regulate the presence of contaminants in the paper process water.
  • chemical levels e.g., biocidal levels
  • the spectrometer 116 and signal processing algorithms 118 permit monitoring of both the compositions and rates of deposition of those compositions onto paper machine surfaces from aqueous process fluids.
  • the process outputs 120 which are generated can be used to control process parameters, and components resulting from organic and inorganic contaminant deposition can be differentiated and independently monitored.

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  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Pathology (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Ecology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Environmental Sciences (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
US09/902,248 2000-07-12 2001-07-10 On-line deposition monitor Abandoned US20020060020A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US09/902,248 US20020060020A1 (en) 2000-07-12 2001-07-10 On-line deposition monitor
AU2001271988A AU2001271988A1 (en) 2000-07-12 2001-07-10 On-line deposition monitor
PCT/US2001/021920 WO2002004941A2 (fr) 2000-07-12 2001-07-10 Surveillance en ligne de depot

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US21783600P 2000-07-12 2000-07-12
US09/902,248 US20020060020A1 (en) 2000-07-12 2001-07-10 On-line deposition monitor

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US10/015,458 Continuation-In-Part US20030112354A1 (en) 2000-06-27 2001-12-13 Wireless transmission of in-play camera views to hand held devices

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US10/620,098 Continuation-In-Part US7796162B2 (en) 2000-06-27 2003-07-14 Providing multiple synchronized camera views for broadcast from a live venue activity to remote viewers

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US (1) US20020060020A1 (fr)
AU (1) AU2001271988A1 (fr)
WO (1) WO2002004941A2 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003028772A1 (fr) * 2001-07-13 2003-04-10 Minntech Corporation Appareil et procede de surveillance de l'efficacite d'un processus d'elimination des films biologiques
US20100015714A1 (en) * 2004-12-04 2010-01-21 Selwayan Saini Measurement of soil pollution
EP3024975A4 (fr) * 2013-07-26 2017-02-08 Ecolab USA Inc. Procédé de surveillance de dépôt
CN112858210A (zh) * 2019-11-28 2021-05-28 安东帕有限责任公司 对用于ir光谱分析的光学表面的损伤的确定
US20220034789A1 (en) * 2018-10-30 2022-02-03 Specshell Aps Non-invasive continuous in line antifouling of atr-mir spectroscopic sensors
US11460400B2 (en) * 2020-07-07 2022-10-04 Sakura Finetek U.S.A., Inc. Use of IR spectroscopy to evaluate penetration of reagents into biological specimen

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1687608A4 (fr) * 2003-11-14 2013-01-09 Alere Switzerland Gmbh Dispositif de prelevement et d'analyse rapide d'echantillons et procedes d'utilisation
WO2007062575A1 (fr) 2005-11-30 2007-06-07 Inverness Medical Switzerland Gmbh Dispositif pour detecter la presence ou la quantite d'un analyte dans un echantillon fluidique, et methode associee
AU2007280929B2 (en) 2006-07-26 2012-03-22 Abbott Rapid Diagnostics International Unlimited Company Analysis device for biological sample
US20140046629A1 (en) * 2011-05-04 2014-02-13 Kaikai Wu Method and apparatus for monitoring deposition
CN105887551B (zh) * 2016-06-06 2019-03-01 瑞辰星生物技术（广州）有限公司 制浆造纸系统中胶粘物的捕获装置和方法
CN109518513A (zh) * 2018-11-13 2019-03-26 岳阳林纸股份有限公司 一种造纸脱墨浆胶粘物控制剂使用效果检测装置及方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4595833A (en) * 1983-09-20 1986-06-17 Sting Donald W Multiple internal reflection cell optical system for use in infrared spectrophotometry of liquid and fluidized samples
US4717827A (en) * 1986-02-20 1988-01-05 Automatik Machinery Corporation Apparatus for on-line spectrophotometric chemical analysis of material in moving process stream
US4743339A (en) * 1986-05-13 1988-05-10 Oskar Faix Method for controlling the digestion of pulp by IR spectroscopy
US4912332A (en) * 1988-06-03 1990-03-27 Research And Development Institute, Inc. At Montana State University Non-destructive methods for detecting organic deposits and removing them
US5282931A (en) * 1992-07-08 1994-02-01 Pulp And Paper Research Institute Of Canada Determination and control of effective alkali in kraft liquors by IR spectroscopy
US5766957A (en) * 1994-03-10 1998-06-16 Applied Research Systems Ars Holding, N.V. Spectrophotometric techniques
US6277330B1 (en) * 1996-09-30 2001-08-21 Aventis Research & Technologies Gmbh & Co K.G. Optical sensor for detecting chemical substances dissolved or dispersed in water

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2276003B (en) * 1993-03-09 1997-01-08 Spectra Tech Inc Method and apparatus for enhancing the usefulness of infrared transmitting materials
EP0714024B1 (fr) * 1994-11-25 2002-01-30 Kyoto Dai-ichi Kagaku Co., Ltd. Procédé et dispositif pour la détermination de peroxyde d'hydrogène

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4595833A (en) * 1983-09-20 1986-06-17 Sting Donald W Multiple internal reflection cell optical system for use in infrared spectrophotometry of liquid and fluidized samples
US4717827A (en) * 1986-02-20 1988-01-05 Automatik Machinery Corporation Apparatus for on-line spectrophotometric chemical analysis of material in moving process stream
US4743339A (en) * 1986-05-13 1988-05-10 Oskar Faix Method for controlling the digestion of pulp by IR spectroscopy
US4912332A (en) * 1988-06-03 1990-03-27 Research And Development Institute, Inc. At Montana State University Non-destructive methods for detecting organic deposits and removing them
US5282931A (en) * 1992-07-08 1994-02-01 Pulp And Paper Research Institute Of Canada Determination and control of effective alkali in kraft liquors by IR spectroscopy
US5766957A (en) * 1994-03-10 1998-06-16 Applied Research Systems Ars Holding, N.V. Spectrophotometric techniques
US6277330B1 (en) * 1996-09-30 2001-08-21 Aventis Research & Technologies Gmbh & Co K.G. Optical sensor for detecting chemical substances dissolved or dispersed in water

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003028772A1 (fr) * 2001-07-13 2003-04-10 Minntech Corporation Appareil et procede de surveillance de l'efficacite d'un processus d'elimination des films biologiques
US20100015714A1 (en) * 2004-12-04 2010-01-21 Selwayan Saini Measurement of soil pollution
EP3024975A4 (fr) * 2013-07-26 2017-02-08 Ecolab USA Inc. Procédé de surveillance de dépôt
US20220034789A1 (en) * 2018-10-30 2022-02-03 Specshell Aps Non-invasive continuous in line antifouling of atr-mir spectroscopic sensors
CN112858210A (zh) * 2019-11-28 2021-05-28 安东帕有限责任公司 对用于ir光谱分析的光学表面的损伤的确定
US11327009B2 (en) * 2019-11-28 2022-05-10 Anton Paar Gmbh Determination of an impairment of an optical surface for IR-spectroscopy
US11460400B2 (en) * 2020-07-07 2022-10-04 Sakura Finetek U.S.A., Inc. Use of IR spectroscopy to evaluate penetration of reagents into biological specimen

Also Published As

Publication number Publication date
WO2002004941A2 (fr) 2002-01-17
WO2002004941A3 (en) 2002-04-25
AU2001271988A1 (en) 2002-01-21

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