33 replies to this topic

[ankur2061]

Narnia,

As provided in post # 1 for guaranteed air pollutant emissions from boiler use these values for dispersion analysis and considering different stack heights with the maximum permissible ground level concentrations of your company or country for chemical and industrial establishments and not for the city of "Luxembourg".

Regards,
Ankur.

Edited by ankur2061, 05 January 2012 - 04:38 AM.

[kkala]

As provided in post # 1 for guaranteed air pollutant emissions from boiler, use these values for dispersion analysis and considering different stack heights with the maximum permissible ground level concentrations of your company or country for chemical and industrial establishments and not for the city of "Luxembourg". Regards, Ankur.

-Allowable ground level concentrations (supposed for ~1 hour average) are not clearly known, and these glcs are asked for. We should try to give clear values (or references) of these allowable glcs around the world, so that an idea of the permissible range for each pollutant can be formed. Then allowable glcs for the specific plant can be established by its personnel; and documented, when permit is submitted to authorities. That is how I understand the procedure, as well as the query of post No 19 by Narmia.
- Posts 20 and 23 indicate that allowable glc=200 μg/m3 for NO2 (hourly average) concerns Luxembourg state (2586 km2) including " the Canton of Esch-sur-Alzette (30 % of the population), which is highly industrialised".
Post No 18 indicates that glc=200 μg/m3 concerns NOx (hourly average, measured as NO2) for Greece. Difference (if any) of reported glc=200 μg/m3 between Greece and Luxembourg is not understood, but a limit of glc = 200 μg/m3 for NOx (hourly average) seems possible for the plant in reference. Supplementary relevant data on NOx glcs will give a better picture. Besides the "Luxembourg attachment" does not provide allowable glcs for SO2 and particulates (hourly average), which should be found.
Hopefully help will be to this direction, target is to trace allowable glcs for SO2, NOx, particulates.
Of course local legislation may pose additional restrictions on stack height (post No 5).

[ankur2061]

Narnia,

Please clarify whether your boiler is located in "Luxembourg" city or in Greece? If yes, then follow the ground level concentrations as proposed numerous times in the earlier posts. If not, then find out the regulations of your country or company regarding ground level concentrations of air pollutants so that hopefully and maybe my hope is misplaced, this endless and meaningless discussion about ground level concentrations in "Luxembourg" and "Greece" can end.

If you are located in the Unted States or if the United States "National Ambient Air Quality Standartds" (NAAQS) are acceptable to your company or the local regulatory authorities of your country / area then refer the link below:

http://www.epa.gov/air/criteria.html

Regards,
Ankur.

Edited by ankur2061, 05 January 2012 - 01:20 PM.

[kkala]

Actually the "Luxembourg" info represents the European Union limits of glcs, as http://whqlibdoc.wh..._06.02_eng.pdf confirms (found just now), extending the data for other pollutants too. The disadvantage for the dispersion model is that only NO2 is given as hourly average. Conversion of glc (average of t1) to glc (average of t2) looks possible, yet Nonhebel's book on air pollution control (~1974) did not present this matter clearly (as I remember).
Bypassing improper comments in previous posts, EPA's standards on air quality could help the specific case in a similar way as the glcs by EU. However check is needed, e.g. the case of allowable NO2 glc below.
According to EPA this is 100 ppb (hourly average), which means 100E-9*46 kg/kmol air = 100*46/22.4 mg/ Nm3 air = 205 mg/Nm3 = 205000 μg/Nm3, versus 200 μg/m3 (hourly average) per EU. EPA does not mention glcs, but it must be so. Is there an arithmetic mistake in the conversion realized? If EPA's figure were 1000 times less, the two values would be practically identical.
Similarly EPA accepts 54 ppb (yearly average), that is 54*E-9*46/22.4 kg/Nm3 = 111000 μg/Nm3, versus 40 μg/m3 (yearly average) per EU. This may not concern dispersion model though.
So comments on the above differences are welcomed. More data on glcs would be also useful.

Edited by kkala, 06 January 2012 - 02:20 AM.

[kkala]

...EPA's standards on air quality could help the specific case in a similar way as the glcs by EU. However check is needed, e.g. the case of allowable NO2 glc below.
According to EPA this is 100 ppb (hourly average), which means 100E-9*46 kg/kmol air = 100*46/22.4 mg/ Nm3 air = 205 mg/Nm3 = 205000 μg/Nm3, versus 200 μg/m3 (hourly average) per EU. EPA does not mention glcs, but it must be so. Is there an arithmetic mistake in the conversion realized? If EPA's figure were 1000 times less, the two values would be practically identical.
Similarly EPA accepts 54 ppb (yearly average), that is 54*E-9*46/22.4 kg/Nm3 = 111000 μg/Nm3, versus 40 μg/m3 (yearly average) per EU. This may not concern dispersion model though.
So comments on the above differences are welcomed. More data on glcs would be also useful.

There is an arithmetic error in above conversions. 1E-9 kg equals 1 μg, not 1 mg. See also http://www.cheresour...mgm3-to-ppm-v/ . Sorry for the mistake, assuming air at 25 oC correct conversion is as follows, concerning NO2.
100 ppb =100E-9*46 kg/kmol air = 100*46/24.45 μg /m3 = 188 μg/m3 (hourly average).
54 ppb = 54*E-9*46/24.45 kg/Nm3 = 102 μg/m3 (yearly average).
Corresponding allowable glcs of EU are 200 μg/m3 and 40 μg/m3 respectively.

[kkala]

G. Ulrich and P. Vasudevan, "Chemical Engineering, Process Design and Economics, a practical guide, 2nd ed, Process Publishing, 2005, p.529, Table 11.3, present ambient air standards as follows.
NO2 100 μg/m3
O3 48 μg/m3
Particles 60 μg/m3
Particles (<10 mm μm) 20 μg/m3
Particles (<2.5 mm μm) 12 μg/m3
SO2 100 μg/m3
SO3 1 μg/m3
Average (sampling) time has not been found, as if it had not been specified.
Conversions to ppmv (written on the table for some gases) were based on air at 1 Atm and 20 oC.
Other points are also of interest (e.g. relation between 40 hr weekly concentration and maximum acceptable glc, even though time is not defined).

Edited by kkala, 07 January 2012 - 11:20 AM.

[kkala]

Attached "glc.xls" contains information on allowable ground level concentrations, collected from work place now that vacations have ended and people returned. Apart from their values, they give an idea of the complexity of such regulations.
Besides they attenuate the noise created by invoking "Luxenbourg", "Greece", "chemical and industrial establishments". Air in reported glcs is considered at 293 oK (~20 oK) and 1 Atm a, specified by the law.

Attached Files

•  glcs.xls   24.5KB   66 downloads

Edited by kkala, 10 January 2012 - 06:29 PM.

[dineshh]

Hi Thanks for such a informative discussion. Can someone provide Calculatiions for Steel Stack for Boilers Height is done as per CPCB Norms, Thickness, dia etc as per IS 6533. If possible by excel sheet

[ramsingh_mech]

Hi ,

Just use my Simple 4 data value submission XL File..

Thanks