utilizing nessi for analytical applications n.
Skip this Video
Loading SlideShow in 5 Seconds..
Utilizing NeSSI for Analytical Applications PowerPoint Presentation
Download Presentation
Utilizing NeSSI for Analytical Applications

Loading in 2 Seconds...

play fullscreen
1 / 34

Utilizing NeSSI for Analytical Applications - PowerPoint PPT Presentation

  • Uploaded on

Utilizing NeSSI for Analytical Applications. Brian Marquardt Dave Veltkamp. New Sampling Sensor Initiative ISA SP76 substrate protocol Component based gas and fluid handling systems Offer flexibility in design and implementation of complicated flow systems for process sampling and analysis

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Utilizing NeSSI for Analytical Applications' - overton

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
nessi modular sampling systems
New Sampling Sensor Initiative

ISA SP76 substrate protocol

Component based gas and fluid handling systems

Offer flexibility in design and implementation of complicated flow systems for process sampling and analysis

LEGOTM based approach to process sample handling

Allows for optimal positioning of analyzers in a process stream

NeSSI Modular Sampling Systems
what does nessi provide
What does NeSSI™ Provide
  • Simple “Lego®-like ” assembly (√)
    • Easy to re-configure
    • No special tools or skills required
    • overall lower cost of build – reduce time to configure/install by 75%
    • improved reliability
    • lower cost of ownership – reduce total cost by 40%
  • Standardized flow components (√)
    • “Mix-and-match” compatibility between vendors
    • Growing list of components
  • Standardized electrical and communication (+)
    • “Plug-and-play” integration of multiple devices
    • Simplified interface for programmatic I/O and control
  • Advanced analytics (+)
    • Micro-analyzers
    • Integrated analysis or “smart” systems
where does nessi fit in the lab
Where Does NeSSI™ Fit in the Lab
  • Instrument/Sensor Interfaces
    • Design standards make development simpler
      • Reduced toolset to be mastered
      • Reduced sample variability to account for
    • Calibration/validation built-in
      • Consistent physical environment for measurement
      • Stream switching and/or mixing allow generation of standards to match analytical requirements
  • Reaction monitoring
    • Microreactors and continuous flow reactors
    • Batch reactors (with fast loop)
  • Sample Preparation
    • Gas handling (mixing, generation, delivery)
    • Liquid handling (mixing, dilution, conditioning, etc.)
benefits of sampling systems to process analysis
Benefits of Sampling Systems to Process Analysis
  • Conditioning and manipulation of sample introduced to analyzer
  • Better control of sample physical parameters
    • Phase
    • Temperature
    • Velocity

Ability to implement sensors at points where measurement parameters are optimal

Flexibility for performing calibration online without removing sensor

Fast switching of streams for real-time measurement, calibration or validation

sensing technologies
Sensing Technologies
  • Gas Chromatography
    • Thermal Desorption (?)
  • Dielectric (√)
  • Spectroscopies
    • IR (?), NIR (+)
    • UV- Vis (+)
    • Raman (√)
    • Fluorescence (+)
  • Impedance (+)
  • Conductivity (√)
  • Refractive Index (√)
  • Vapochromic Sensors (+)
  • GLRS (+)
  • Particle Sizing
    • Light scattering (?)
  • Turbidity (+)
  • pH (√)
  • RGA (+)
  • Mass Spectrometry (√)
  • LC, SEC, IC (+)
  • Terrahertz (?)
natural gas property testing
Natural Gas Property Testing
  • Collaborative project with Brooks Instruments to test new Gas Property Instrument (GPI) for Gross Calorific Value and Wobbe Index of natural gas
    • Adaptation of thermal mass flow technology to measure physical parameters of gas
  • NeSSI™ system used to generate air/propane mixtures with known properties to simulate natural gas variations
gpi testing results
GPI Testing Results

Raw MFC (% Full Flow N2)

Gross Heating Correlation

Corrected (Vol %) Flow

Wobbe Index Correlation

gpi conclusions
GPI Conclusions
  • First real application of gas blending or mixing on NeSSI in our lab
    • Developed preliminary LabVIEW software control for MFCs and pressure transducers
    • Brooks has agreed to assist in calibrating our MFCs for multiple gases
  • GPI results looked fairly good over planned application range of natural gas properties
vapochromic probe design sensing system
Vapochromic Probe Design & Sensing System


Vapochromic Film

Probe Tip

Dual Fiber Probe

Excitation Fiber

Light Source

Blue LED


& Detector

Collection Fiber

example nessi sensor interface
Example NeSSI Sensor Interface
  • Sensor is a vapochromatic compound
    • Responds to different compounds by intensity and wavelength shifts in fluorescence signal
    • Optical detection using simple VIS spectrometer
      • LED excitation light source
      • Simple reflectance 2 fiber optical measurement
  • Use of BallProbe to provide single-sided optical interface
    • Vapochrome coated on ball surface
  • NeSSI™ system to control delivery and mixing of gas stream
vapochromic humidity sensor
Vapochromic Humidity Sensor

- Measurment time – 100 ms

- 3 reps per concentration

  • 2 PC calibration model
  • humidity range: 10 – 80%
  • Ohmic feedback control humidity generator used for reference stds.
oxygen gas sensor calibration
Oxygen Gas Sensor Calibration
  • 2 PC PLS model
  • range = 0-100%
vapochromic o 2 sensor vs electrochemical do probe

Response of Optical and DO Probes, Second Timed Exp.



Optical @560nm

DO Probe





Sensor Optical Intensity (relative counts)

DO reference measurement (O2 %)











Elapsed Minutes

Optical response inverted and offset for comparison

Vapochromic O2 Sensor vs Electrochemical DO probe
vapochromic btex sensing
Vapochromic BTEX Sensing
  • Vapochromatic compound screening for benzene, toluene, ethylbenzene and m-xylene (BTEX) sensitivity and selectivity
    • Need to find the best available compounds for sensor array approach
    • Initial milestone: benzene detection
    • Establish sensitivity
      • (can we detect low enough levels?)
    • Characterize interferents
      • (can we distinguish mixtures?)
  • NeSSI™ system to control delivery and mixing of gas streams
nessi gas vapor system
NeSSI Gas/Vapor System

Single inlet line (N2)

Outlet lineto flow cell

Standard Ace Glass impingers

  • NeSSI substrate with 3 MFC’s
  • 2 bubblers for vapor generation
optical flow cell
Optical Flow Cell
  • Flow cell is a simple cross fitting
    • 6-around-1 fiber optic for source and collection
    • Delrin rod with sensing compound coated on end
  • Multiple crosses can be chained together for screening several compounds at once
  • Optical detection using simple VIS spectrometer, LED excitation light source
    • Simple reflectance optical measurement
vapochromic nessi sensor design
Vapochromic NeSSI Sensor Design
  • simple design
  • reversible response
  • low power
  • inexpensive
  • NeSSI compat.
  • fast response times
  • high quantum efficiency
  • long term sensor stability
  • sensitive to a variety of analytes
  • large number of available vapochromic compounds (selectivity)
experimental details
Experimental Details
  • Three gas streams mixed prior to outlet
    • MFC #1 pure N2 carrier (no bubbler)
    • MFC #2 run thru bubbler with benzene liquid
    • MFC #3 run thru empty bubbler (diluter)
  • MFC #1 and MFC #2 flow summed to 50% full flow (FF, 250 sccm)
    • As bubbler flow ↑ carrier flow ↓
  • MFC #3 held at either 50% FF or 5% FF
    • Additional level of dilution between runs
  • Spectra collected every 2 seconds
  • LabVIEW program automates setting flow rates on MFCs, sequence timing, and data logging
vapochromic response
Vapochromic Response

* MFC #3 run at 5% FF rather than 50% FF

vapochromic response1
Vapochromic Response
  • These are the 2 most sensitive compounds of the 6 looked at in this study
  • There is plenty of optical sensitivity to go to lower conc.
  • May need to implement “reset” techniques to zero response
vapochromic 4 response
Vapochromic #4 Response

Differential response!!??

screening conclusions
Screening Conclusions
  • Early results look good for benzene sensitivity
    • 2-3 candidates
    • Clearly need more dilution capability
  • Need to speed up the screening
    • Multiple simultaneous compounds
    • Switching/multiplexing NOT the answer
      • New multichannel spectrometers will improve screening
new gas sensor testing system
New Gas Sensor Testing System
  • More capability to generate analytical vapors, gas blending, and on-line dilution of vapor streams for method development work
  • Two systems (one at CPAC, the other at UM) will facilitate collaboration with Kent Mann
  • NSF Funding applied for (Aug. 06)
    • Bob Sherman, CIRCOR, committed to providing one system
fuel cell research

3 Voltmeters,1 Ammeter

Thermocouple and Humidity sensor

Thermocouple and Humidity sensors

H2 in

PEM Fuel Cell

Air in

Both Streams Purge to outside environment

Tank (might run system without a tank)


Or Pump

Fuel Cell Research
  • Goal: to study the water uptake properties of Nafion 112 by varying the relative humidity of the input gas streams to better understand membrane hydration and its effects on fuel cell performance.
    • Senior Project for ChemE undergrad student team
  • NeSSI™ System for gas flow and humidity sensing
fuel cell cont
Fuel Cell (cont.)
  • Simple NeSSI system design being built by Swagelok
  • Preliminary system calculations done by students
  • Vapochromic humidity sensors designed
  • Expect this activity begin this summer
fluid dynamics modeling
Fluid Dynamics Modeling
  • Project with Dr. Finlayson and undergrad student Daniel Yates, Chem. E.
    • Utilize NeSSI™ components as objects for computation fluid dynamics modeling
    • Availability of NeSSI™ systems and parts allows for experimental work to verify/test model results
  • Provides academic training and exposure to real-world hardware in a compact and rugged platform
    • Can start simple and add complexity by including more components
where are we now
Where are we now?
  • Development continues on control system
    • Data I/O, comm., and control hardware
    • Software for DAQ, automation and control
  • NeSSI microreactor system becoming reality
    • Parker Intraflow™ fluidic system delivered
    • IMM, Microglass, CPC mixers and reactor components here or coming soon
    • LC, Raman, dielectric, RI detection
  • Headspace and gas analysis systems
    • Horiba RGA analyzer running
    • Vapochromic sensors being designed and tested for NeSSI applications
    • GC interface to NeSSI under development with Infometrix (WTC Proposal submitted)