Portable IR/PID gas analyzer. ECOPROBE 5. RS DYNAMICS. A new dimension in detection of contaminant indicators. . Soil Contamination Survey. Gas from the pore space in soil and rock formations is known as soil vapour. .
A new dimension in detection of contaminant indicators
Gas from the pore space in soil and rock formations is known as soil vapour.
The composition of this phase, in particular the presence of organic compounds, reveals vital information about pollution of the subsurface contaminant.
Organic compounds constitute a group of contaminants which impact severely on groundwater resources.
The following types of contaminants are addressed:
1. Liquid organic materials including hydrocarbons (mainly petroleum products) and chlorinated hydrocarbons (industrial solvents, metal-cutting oils etc.)
2. Organic vapours from landfills and from gas leaks
Factors affecting in situ SV measurements:
1. Presence of Methane of nature origin: Methane occurs in different concentration everywhere in the soil environment, which confuses all total based in-situ measurements.
2. Type of contaminant: for the SVS to be applied successfully, the contaminant of interest must yield sufficient vapour phase. (Some compounds like transformer oils, PCB and certain phenols create very low vapour phase and require special sampling technique).
3. Zoning : differences in several physical properties of the compounds present in a complex contaminant (vapour pressure, solubility in water, mobility in the subsurface, resistance to degradation etc.) may contribute towards the heterogeneous character of a pollution plume.
4. Surface contamination:a pollutant occurring in the surface layer will seriously affect the distribution and concentration patterns of an underlying, deep source of contamination.
5. Age of a contaminant: All petroleum products experience some degree of natural biodegradation process in the subsurface environment. Lighter HC are more readily degraded than the heavier compounds. After a certain period of time the spectral composition of contaminants will dramatically change; moreover, some contaminants may become morphologized, that is: composed of non-toxic aromatic compounds which are out of the basic hydrocarbon spectrum.
6. Soil temperature: vapour density and vapour diffusion will increase with increasing temperature.
7. Soil moisture: the presence of moisture will reduce the effective porosity which will negatively affect the migration and the volume of SV available for investigation.
8. Soil permeability: may dramatically influence the measured value of concentration of the free SV phase.
Previous SVS methods
Previously used time-integrated SVS methods applied special absorbents into which the analyzed soil vapour was absorbed during a relatively long time-interval.
These methods did not meet natural conditions and yielded incorrect quantitative results.
Mix the identical quantity of liquid contaminant
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Poorly permeable soil clay
Permeable soil sand
Measurement of SV concentration in both samples shows the difference of up to 2 or 3 decimal orders.
RS DYNAMICS developed a special instrumentation -- Ecoprobe 5 -- which provides a solution for most of the above-mentioned complicated conditions and offers the true in-situ method for a reliable soil contamination survey.
Ecoprobe 5 eliminates sampling and sample transport problems to the lab, in this way offering fast, cost- effective and reliable location of contaminant sources and trajectories of the contaminant spread.
The air is sucked into the probe and continuously analyzed in the instrument
Ecoprobe 5 shows the course of measurement overview on the screen
Graphs of concentrations versus time
The identical quantity of contaminant is mixed into the samples
Portable and compact highly sensitive gas analyzer providing cost-effective and reliable in-situ results
Comprises two autonomous analyzers in one case
Combination of PID and four channel IR analyzers provides solution for a variety of contamination survey tasks.
Soil vapour survey was made by CSIR/ Petrocon (Council for Scientific and Industrial Research), South Africa
Soil vapour survey was made by CSIR /Petrocon (Council for Scientific and Industrial Research), South Africa
Soil vapour survey made by Prote, Poland
Optional stationary version of IR Ecoprobe 5 analyzer
Monitoring station over a large pressurized underground gas reservoir
Commercial use of GPS has proven invaluable in many fields. It can be used to track everything from migrating animal herds to the creep of the earth’s crust.
GPS consists of 24 satellites in predictable orbits around the earth. The system provides 24-hour positioning information.
Ecoprobe 5 is the first world-wide geophysical instrument to provide GPS positioning !!
GPS satellite orbital information is referenced to WGS 84. WGS 84 is an earth - fixed global reference frame using latitude and longitude coordinate system to locate points on the Earth’s surface.
The GPS system in Ecoprobe 5 can be used if a specific software is activated and if a special RS DYNAMICS GPS receiver is available.
Depending upon accuracy requirements, users may select from GPS systems with
Data are saved in an orderly manner
Result value measured by PID
detection limit 0.1 ppm upper limit 4000 ppm (output also in mg/ m)
detection limit 0.1 ppb(0.0001 ppm) upper limit 100 ppm (output also in µg/m)
HISENS mode is extremely sensitive (intended for precise measurement ). It is not recommended for the typical soil vapour survey since factors like moisture, presence of methane, under-pressure may influence the results.
Fast and cost effective identification of relative concentration cloud, contaminant sources, path and the range of contaminated area. Table of measured compounds by PID offers mixtures of most common contaminants (Diesel Fuel, Gasoline, Jet Fuel). Select the compound characterizing the contaminant to get most reliable data.
Ecoprobe 5 is calibrated for Isobuthylene (Isobuthylene represents the most suitable gas which is also used in laboratory gas chromatographs). Responses to other compounds are different. The instrument is, however, automaticaly calibrated for about 200 compounds. In spite of this fact Ecoprobe 5 is not a spectral sensitive analyzer.
Application of PID Analyzer plants
1. For measuring small values of contaminant concentration
2. For measuring wider spectrum of contaminant
3. For quantitative measurement
Provides selective detection of METHANE, Petroleum Hydrocarbons and Carbon Dioxide.
If hydrocarbons are present in the contaminant, consequent continuity between PID and IR outputs can be observed.
Application of IR Analyzer plants
Relative and fast in situ monitoring of contaminant
1. Values from all channels for a particular line
3. Course of measurement on one site
Contour map of subsurface contaminant location
THE END etc.