Environmental Sensing
description
Transcript of Environmental Sensing
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Environmental Sensing
• Smart Landfill: Landfill gas analysis
• Smart Dust: Toxic dust analysis
• SmartCoast: Nutrient monitoring
• Marine Sensor Systems
• Chemical Plume Monitoring
• Toxic Metals in Water
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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Smart Landfill
Breda Kiernan, Weimin Guo, Conor Slater
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Aims of the Project
•Sponsored by the Environmental Protection Agency, Ireland•Tasked with the development of an autonomous system for monitoring landfill gas emissions and landfill gas migration especially methane and carbon dioxide
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
CH4
CO2
VOCs
Landfill gas generation
Borehole well
Gas sample extracted
Analysed using IR gas sensor
Chemometric program analyses data and decides if concentrations are within threshold limits
If thresholds are exceeded, a message to sent to personnel onsite to investigate further
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Base-station location
Gas monitoring points
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Current status• Infrared gas sensors (CO2 and CH4)
calibrated over the range necessary (0-1.2%)
• Wireless comms approaches have been evaluated (GSM, Bluetooth…)
• GPS can be used to locate each sensor node and used to generate a dynamic model of the whole landfill site.
• Predictions using artificial neural networks of the gas concentrations when compared with the voltage output of the sensors is within 5 %. Therefore, the Smart Landfill system has merit as a warning system using threshold values to determine which concentrations are “normal” and “high” .
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Infrared sensor for CO2
Perkin Elmer GX FTIR instrument
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Future Work• Power: Currently 9V battery with 7000 mAh. In the future systems
will function through local power scavenging (solar, wind…)
• Data retrieval: Inter-sensor distances will be typically 100-500m; ideally suited for variety of low power wireless communications approaches
• Field trials for system deployment on target for late September/early October
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Smart Plant
• Sponsored by EPA
• Monitoring of odorants at waste transfer stations.
• In the first instance, ammonia and hydrogen sulfide are being monitored.
• Used as a warning system for build up of chemicals beyond the olfactory threshold.
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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EPA Project: “Autonomous sensors for environmental monitoring- detection of
heavy metals in dust”
Tanja Radu, Conor Slater, Daniel Kim
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Elements of the strategy therefore include:
• Simple sampling and sample processing - ideally on the solid material directly, without reagents
• Ability to detect a range of targets using a single approach
• Sufficient selectivity, sensitivity, LOD
• Relatively low power - sufficient to be operated from local power sources
• Compatible with digital communications
“How can we remotely monitor a range of toxic metals in dust blow-off in real time?”
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Lead in soil
Lead (mg/kg)
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NOTE: Median concentration of lead in Irish soil is 26 mg/kg !!
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Gortmore
Silvermines
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Arsenic in soil
Arsenic (mg/kg)
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NOTE: Median concentration of arsenic in Irish soil is 12 mg/kg
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Dust blow occurrence - a real threat
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Portable XRF- our method of choice
• Light, hand held instrument (0.8 kg)
• Ideal for field analysis
• Simultaneous analysis of up to 25 elements (Pb, Cd, Sb, Cu, As, Hg, Ag, Zn, Se…)
• Simple point and shoot operation
• Real time analysis of solid sample - no lengthy sample preparation
• Remote operation capability
• Non destructive method- sample preservation
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Excellent preliminary results- Pb analysis
Trial of XRF in DCU:
- for soil samples - excellent agreement with AAS
- For simulated dust samples- excellent correlation of XRF reading and calculated values
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
How to automate XRF?
MICRO CHIP GSM SYSTEMXRF ANALYSISPUMP/SAMPLING
Input info: TemperaturePressureWindHumidity…
EXAMPLE:If T>20 oC, dryand wind = SEthen start sampling
High flow pumpBattery operatedRemote control
A unique sampling system has been developed by the ASG!
Wireless communication
Sending reading to Internet or mobile phone
Remotely controlled NITON 700 XRF instrument
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Sampler
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
The vision for the future
• “Smart” instrument – taking samples only when dust blow is likely to occur
• Autonomous analytical measurement
• Remote control monitoring
• Low-power, environment friendly monitoring
• Real time monitoring
• Web-based air pollution monitoring systemUsing this approach we will deliver a remote, real time, system which, for the first time, will provide unambiguous data about the levels of these toxic metals associated with specific blow-off events
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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SmartCoast:Autonomous Phosphate Sensor
John Cleary, Conor Slater
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Autonomous Phosphate Sensor• Component of “SmartCoast” project, which aims to
develop a smart water quality monitoring system, to aid compliance with increased monitoring requirements under the Water Framework Directive.
• Phosphate is a key limiting nutrient in freshwater ecosystems.
• Eutrophication: A major water quality problem in Ireland and many other
countries Elevated nutrient levels lead to excessive
growth of algae and aquatic plants Oxygen depletion fish kills Algal blooms toxicity in water bodies
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Objective and Requirements
• Develop an autonomous, remotely controlled phosphate sensor capable of monitoring PO4
3- at appropriate levels at remote locations over long deployments
• Requirements: Sensitive Stable chemistry Communicate wirelessly Low power Robust & portable Low cost & low maintenance requirements
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Principle of Operation• Yellow method for phosphate detection
Forms vanadomolybdophosphoric acid (yellow)
Absorption proportional to phosphate conc. Advantages
Excellent reagent stability Fast reaction time (minutes)
• Microfluidic technology Minimizes reagent consumption, storage
requirements and pumping power• UV-LED and photodiode
Low powered, inexpensive & sensitive optical detection
Talanta vol. 71, no. 3, pp. 1180–1185 , Feb. 2007.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Field Trial• First generation sensor was trialled at Osberstown WWTP
• 3-week trial with validation using existing online monitor
• Good correlation achieved
IEEE Sensors Journal (Accepted Aug. 2007)
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Current Status• Mark II sensor designed to build
on the successes and address the limitations of the original.
• Improvements Lower power, more flexible fluid
handling system. More sensitive optical detection system. More reliable and lower powered
communications using GSM modem in SMS mode.
2 point calibration protocol. Solar panel for energy harvesting
during long deployments. Improved ruggedisation.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Current Status• Preliminary experiments
show improvement inlimit of detection LOD ~60 ppb vs. ~300
ppb with original system
• Scale-up 5 units of Mark II Sensor have been fabricated Currently undergoing laboratory assessment Field trials to be carried out in coming months
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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Marine Institute Desk Study:
Jer Hayes
Instrumentation interface, communications and data management architecture issues for marine sensor systems, including sea-floor observatories
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Background
•This desk study project aims to:
-To identify key niche areas of innovation in the areas of sensor systems (especially seabed observation) and identify and assess Irish technical and industry capabilities in the technologies involved
- To provide solutions to the emerging interface between sensor systems development and operational requirements under the Water Framework Directive
- To provide solutions for linking the data acquisition platforms currently in use and planned.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
SmartBay
• The component technologies of SmartBay will include:
- a fibre-optic cable from shore to an underwater hub- a variety of instrument nodes and sensor packages a calibration site/facility- multi-beam digital map and geotechnical survey of the area
- deployment of a moored buoy, and possibly drifting buoys- navigation and telemetry
infrastructure.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Current Status
• Generated three reports –
Current sensory systems and returned data structures used across the MI
Establishing protocols for linking data acquisitions platforms with the MI data warehouse
The connection of buoys, submarine monitoring stations, coastal and on-shore monitoring systems
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Interoperability
Marine
Land
Prior to deployment the puck is loaded with the information that is necessary to fully use the instrument when it is plugged into an sea-floor observatory
backbone.
Wireless sensor networks – can link data acquisition platforms MI Newport
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MAC MOTE
MAC MOTE
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NCSR DO (Serial Output)
MI Rain Gauge
PSOC + WQ101 Temp sensor
Drive by data Collection
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Current Status
• Adaptive sensing / ambient conditions
Phosphate system
WebInterface
Phosphate Instrument
www.nra.ie
ww.met.ie
Monitoring program
GSM
Serial Server Database
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Additional information• Also worked on - Water purification process monitoring
using wireless sensor networks:
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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Monitoring Chemical Plumes in an Environmental Chamber with a Wireless
Chemical Sensor Network
Stephen Beirne
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Opposing LED chemical sensor integrated with modified Mica2Dot wireless sensing platform
Modified Mica2Dot Mote
• Modified to include a power source suitable for laboratory sampling rates.
• Opposing LEDs sensor coated in BPB reagent – Sensitive to increase in acidity
• Real-time monitoring. Sensor sampled at a frequency of 0.5 Hz. One sample value per data packet
• Data Acquisition via Visual Basic interface
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Sensor mounting and protecting sub-assembly of Wireless chemical sensor node enclosure
Sensor Hood
Opposing LEDs Chemical Sensor
Sensor Mounting Sleeve and Hood connection point
¼” BSP threaded fitting drilled through
Ø 9mm
Limiting Collar
Semi-transparent view of wireless chemical sensor node enclosure assembly
Sensor mounting sub-assembly
Cylindrical casing
Mica2Dot Mote, Radio antenna, 2 x AA battery power supply & On/Off header switch
Casing End Cap
Wireless Chemical Sensor Assembly
• Sensor covered by hood to reduce ambient light.
• Node housed in an enclosure to protect electronics from corrosive acetic acid. Also allows for attachment to the Environmental Sensing Chamber.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Sensor Reproducibility
Smoothed Response Data of Wireless Chemical Sensor Node Exposed to Three Consecutive Plumes of Acetic Acid Laden air
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• Exposed to acidic vapour by means of a bubbler unit. Bubbler contents 2:1 ratio of Water and Conc. Acetic acid.
• Response to stimulus is clearly distinguishable.
• Sensor shows excellent reproducibility.
• Not a “Single Shot” device – Can be used to monitor consecutive events
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Sensitive to Plume Flow Rate
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• Sensor exposed to acidic plumes at varying flow rates.
• Higher flow rate induces higher concentration level at node location, as shown by collected data
• Data displayed as % Deviation from initial baseline value – Multiple nodes will not have a common baseline
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Wireless Chemical Sensor Network Arrangement
• Developed node allows for a network of similar nodes to be deployed to monitor a chemical plume event.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Plume Tracking using a low-cost Wireless Chemical Sensor Network
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• Sensor network exposed to acidic plume for a period of 200 s (approx).
• Dense acetic-acid constrained by river channel walls
• Data allows the tracking of plume development through the chamber.
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Reactive Wireless Chemical Sensor
Actuator Network (WCSAN)
• Have displayed the ability to track a chemical plume in real-time using a low cost chemical sensor network.
• What should we do with the data? …. Use collaborative sensor information.
• Event classification - 2 or more sensors display a significant change in response.
• Data acquisition software allows output control.
• Respond to this event in real-time by sending a control signal from the interface to activate an electro-mechanical purge system.
• Results in a real-time reactive Wireless Chemical Sensor Actuator Network (WCSAN)
This material is based upon work supported by Science Foundation Ireland under Grant No. 03/IN3/1361
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
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Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare
(MASTRA)
Aleksandar Radu
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Aim of the project•To develop miniaturised all-solid-state ion sensors with low detection limit based on materials science and ion selective electrodes (ISEs) technology.
Plan•To construct sensors based on novel conducting polymers coupled with novel ion-selective membranes able to achieve trace-level ion detection and stable sensor performance.
•To miniaturize created potentiometric device
•To apply the sensing device for determination of toxic heavy metals and other ions of
importance to human health and welfare.
Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare (MASTRA)
CLARITY
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare (MASTRA)
Current status •Understanding factors that lead to lowering of the detection limit in classical potentiometric sensors
Potential response of Cs+-selective ISE.
A) classically prepared ISE.
B) ISE with optimised inner solution.
C) Response obtained for electrode B under higher stirring rate of the sample (reducing aqueous diffusion layer thickness).
D) Response obtained by increasing of the amount of PVC in the membrane cocktail (reduced ion diffusion) and decreasing of the amount of ionic sites.
Radu, Aleksandar; Peper, Shane; Bakker, Eric; Diamond, Dermot: Electroanalysis, 2007, 19 (2-3), 144-154
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare (MASTRA)
Current status cont’d•Development of solid-state potentiometric sensors with low detection limit
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Response of Pb-selective, solid-contact ISEs in 10-3 M nitric acid.
McGraw, Christina; Radu, Tanja; Radu, Aleksandar; Diamond, Dermot: Electroanalysis, submited
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UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare (MASTRA)
Current status cont’d•Application of developed soil-contact potentiometric sensor in soil analysis
y = 1.1083x - 0.1771
R2 = 0.959
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Comparison of Pb2+ concentrations in soil samples digested in 1 × 10-3 M nitric acid obtained by AAS and ISEs.
Radu, Tanja; Radu, Aleksandar; Diamond, Dermot: Proceeding of SPIE Europe, Remote Sensing, Florence, 2007, accepted
CLARITY
UNIVERSITY COLLEGE DUBLIN DUBLIN CITY UNIVERSITY
Miniaturized all-solid-state sensors for trace analysis of substances relevant to health and welfare (MASTRA)
Future directions•Miniaturization of developed solid-state ISEs (lot of experience and expertise in the group, i.e. miniature, microfluidic-based chip in optical analysis (see picture on the right))
•Integration of miniaturized solid-state ISEs with miniaturized solid-state reference electrode (developed by Abo Academi, Finland) (lot of experience and expertise in the group, i.e. field deployable devices (see picture on the right))
•Application in environmental analysis