Stack emission sampling

Emission dust sampling options

The reference EN 13284-1 provide two different way about stack sampling, depending on emission conditions. The first option provide sampling with a standard probe  with inserted perpendicularly into the duct filter holder to the emission flow. This option is recommended for emissions not involving humidity and with low temperature. It allows using non-perpendicular filter holders to sampling flow, reminding to consider also as part of the sampling all the collected parts ahead of the filter.


In-Stack filter holder sampling
The probe has been designed and produced to follow as strictly as described in the reference EN13284-1 and EPA Method 17. The probe provide a positioning of filter holder into frontal mode to the chimney emission flow trough nozzle positioning. European normative specifies a reference method for calculating low concentrations dusts into gaseous flows channeled into minor concentrations compared to reference conditions 50 mg/. EPA 17 require a non moisture presence inside the duct. The norm has been validated particularly around 5 mg/ on an average sampling time of half an hour. Generally it can be applied to expulsed gas from stationary sources and upper concentrations. If gases contain unstable, reactive or semi-volatile substances, calculus depends on sampling conditions and filter treating.
IsoFlow201 Isokinetic Calculator, which had settled with actual parameters described in the normative, may obtain the measurements involving flow rate, differential pressure and temperature. International standards are available as dedicated single software application. All data referred to stack condition can be evaluated, stored in the memory and viewed for easy sampling set-up.


Stack dust sampling in compliant with EN-13284 and EPA 17


Com2-HE + IsoFlow

Stack dust sampling in compliant with EN-13284 and EPA 17


Com2-ISO / He-ISO

Stack dust sampling in compliant with EN-13284 and EPA 17

Sampling procedure
A known gas volume extracted by the main gaseous flow in representative points of sampling for a measured period, with a isokinetic checked flow rate and a measured volume. Dusts collected in the gas sample are divided by a pre-weighted plain filter, which later will be dried and weighted once again. Also upstream filter deposits of the sampling system are recollected and weighted. The increasing filter mass and upstream filter collected one, are due to collected dusts from the sampled gas, which consent to calculate dust concentration.  
The probe can been provided totally assembled and it concerns Pitot tube and K probe for temperature revelation. All the parts of the probe may be disassembled by the user and be used singularly. It is also available a kit for dust sampling with inserted filter holder inside the chimney dedicated to extremely narrow sections. For the correct positioning or calculus of isokinetic parameters, you have to refer to IsoFlow201/202 flow rate measurer.


Out-Stack  filter holder sampling with heated probe
The second option (EN-13284) provide using an isokinetic heated probe with filter holder, placed downstream and inserted in a heated box. The method may be used either with manual system either automatic system in compliant with requirements in ISO-9096 normative. Sampling with the manual system will be performed once finished the duct evaluation, with the corrected sizes to have a right test performance.  Speed measurements have to be performed using normalized Pitot tubes of kind L, as described into ISO 3966:77. Alternatively, they may be used also Pitot S, whether they have been calibrated like standardized Pitot tubes. Conduct pressure and temperature have to be measured to calculate effective volumetric mass of the gas, considering gas composition. When expressing dusts concentrations on dry base, and/or when the concentrations have to be expressed in relationship to reference oxygen, humidity measurement and/or oxygen have to be performed near the sampling floor.

Heated probe with external heated filter holder
The tube part between the nozzle and the filter (suction tube) has to be long enough to allow access in all sampling conduct points. The suction tube and the filter holder have to be controlled temperature, which provokes evaporation of possible water drops or avoid difficult filtering related to acid gases with high dew point. Generally filters with 50mm diameter, with an associated flow rate from 1 m3/h to 10 m3/h. Sampling time for each point is between 30 and 60 minutes. As regarding filtering membranes, it is recommended using membranes containing an organic binder because of the level of their impurities. Filtering membranes haven't performed particular interferences are the ones in quartz fiber or in glass fiber PTFE coated (maximum temperature of usage 280°C).
In alternative also glass fiber filters may be used, but sometimes they might perform any kind of interferences caused by compost reacting to the same glass fibers.
The manual sampling can be performed with every AirCube™ model in the series,  combining with IsoFlow 201 Pro isokinetic parameters calculator. The isokinetic automatic sampling is compliant with ISO-9096 and ISO-10780 standards and it will be performed with AirCube™ COM2 ISO and AirCube™ HE ISO models. Alternatively  AirCube™ Com 2 and HE samplers may be directly interfaced with IsoFlow 201 Pro measurer.


Stack dust sampling in compliant with EN-13284 and EPA 5


Com2-HE + IsoFlow


AUTOMATIC METHOD (EN-13284-1, EPA-5, ISO 9096)
Com2-ISO / He-ISO
Stack dust sampling in compliant with EN-13284 and EPA 5