Expert assessment on flue height
Conducted emissions of gaseous or dust-bound pollutants are produced during numerous industrial and commercial processes, as well as with domestic heating. A large part of emissions are generated by combustion processes.
As a precaution against harmful environmental effects, a set of minimum requirements for the discharge of exhaust gases have been stipulated, compliance with which needs to be verified. These minimum requirements also include the chimney height as an essential parameter. The basis of the assessment is always an undisturbed removal of the exhaust gases with the free air flow as well as sufficient dilution of the exhaust gases, which must be ensured regardless of the specific application.
The methodological approach for identifying and evaluating the discharge conditions of conducted emissions depends in general on the size, characteristics, and surroundings of the facility. There are clear distinctions under the Federal Pollution Control Act (BImSchG) between facilities subject to licensing as well as smaller plants, and plants that emit odorous substances.
The concrete minimum requirements for the discharge of waste gases are formulated in the Technical Instructions on Air Quality Control (TA Luft 2021) for plants requiring a permit, in the 1st BImSchV for small plants, and in Annex 7 of TA Luft 2021 for plants emitting odor-intensive substances. These requirements are supplemented by various VDI guidelines and instructions of the Regional Working Group on Pollution Control (Länderarbeitsgemeinschaft Immissionsschutz (LAI)).
The emitted substances, emission mass flow rates, flow rates, stack diameter, and the exhaust temperatures, in particular, are considered relevant emission parameters for stack height assessments. Environmental factors such as the height of surrounding buildings and the orographically structured terrain surrounding the facility have a significant influence on the required dispersion height in addition to the influence parameters of the emission source itself. Additional requirements also arise for emission sources that emit odorous substances.
Despite extensive regulations for the evaluation of dispersion conditions of stack gases, in practice there are always situations that are not, or only partially covered by the existing regulations. Take advantage of our extensive experience from working on a variety of projects in this domain for determining the required dispersion height for your emmissions sources and let us advise you the on the ideal solution for your specific case.