Emissions inventory of air pollution

Knowledge of the types and rates of emission has been fundamental to any study of community air pollution. There have been several ways in which source information can be extremely used. It can be of help in designing the air sampling and air analysis programmes, and interpreting the resulting quality data. From the research standpoint, detailed emission data have been necessary for constructing mathematical models of the atmosphere for purposes of predicting future concentrations of specific pollutants. The establishment of emission standards and planning and zoning regulations has been greatly enhanced by6 the availability of current and predicted source information. It must be stressed that, while knowledge of emission sources has been fundamental to an understanding of the nature, causes and effects of air pollution in a community, air pollution sources information per se gets definitely limited in it6s value. In other words, data on quantities of a pollutant emitted in one area have been not necessarily directly relatable to the situation in another area. The systematic collection and collation of detailed information concerning the air pollution emission in given area have been referred to as an emission inventory. To be of greatest use, such an inventory should have as much information as possible on the types of sources as well as their contributions in terms of the composition and rates of discharge of the individual pollutants. The choice of units of expression in and emission inventory has been immaterial as long as the system has been consistent, realistic, and can be correlated with the particular air pollution condition or effect in question. Emissions have been commonly reported in terms of weight of pollutant per unit of time. While the inventory is able to cover the entire region under study, attention must be paid also to sources and emissions which are not within the area, but which may contribute significantly to the air quality in the study area. While principal effort is directed at man-made source, the contribution of relevant natural sources must also be taken into count.

A convenient classification of source types has been as follows:

1.      Fuel-burning for heat and power production: It includes the operating of heating equipment utilizing coal, oil, gas and wood for power production, space heating, and hot water. Included in this category have been the following sources:

• Utilities: These have been the large steam-electric generating plants, both public and private.

• Residences: These include single and multiple dwellings such as private homes, duplexes, and apartment houses.

• Industrial establishment: This category includes:

• Commercial, establishments like store, hotels, clubs etc.

• Processing, including laundries, dry cleaners, garbage, and service stations.

2.      Incineration: This category represents: 

•   Municipal incinerators 
•   Industrial and commercial incinerators
• Residential-type incinerators 
• Apartment house incinerators
• Open refuse-burning

3.      Transportation: This category includes: 

• Motor vehicles, powered by internal combustion or diesel engines.
• Trucks or buses 
•  Railroad engines 
• Ships 
• Aircraft

4.      Industrial and commercial: This class incorporates the various technological operations and processes such as: 

• Manufacturing (metallurgical plants, chemical plants, refineries, etc) 
• Agricultural operations (spraying, dusting and field burning) 
• Commercial activities (dry cleaning, spray painting, printing) 
• Miscellaneous (sewage treatment, construction, demolition).