Faculty of air transport engineering the department of «air navigation systems»


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1.3.2. Airport air quality.
Interest in airport air pollution began to increase in the early 1970s, when commercial transportation using turboprop aircraft became more active. Chemical air pollution at airports is represented by such aviation emissions as carbon oxides (CO, CO2), nitrogen oxides (NOx), sulfur oxides (SOx), hydrocarbons (HC) and suspended particles formed as a result of engine operation and the combustion of aviation fuel (Figure 6).
Figure 6. Estimated long-term prospects for reducing aviation noise by 2030 [5]

Aircraft category

Long-term goals, db

 Regional jet aircraft
40 t (nominal)
50 t (maximum)

21.5±4
17±4



Short-range/medium-range twin-engine aircraft
Turbofan:
78 t (rated)
98 t (max)



30±4
26.5±4

Twin-engine trunk-route aircraft
230 t (nominal)
290 t (max)



28±4
24.5±4

Four-engine mainline aircraft
440 t (nominal)
550 t (max)



27±4
20.5±4

Sources of emissions associated with aviation can spread and lead to deterioration of air quality in nearby localities. These emissions pose a potential risk to public health and the environment, as they can cause an increase in the concentration of ground-level ozone and lead to acid rain. National and international air quality monitoring programs constantly require authorized aviation and government organizations to monitor air quality near airports. Special attention is also paid to the environmental impact of aviation related to water quality, waste management, energy consumption, and the impact on the local environment near airports (especially the prevention of fuel leaks).


Over the past few decades, significant progress has been made in reducing emissions due to the increased environmental friendliness of aviation fuels (partial replacement of kerosene with liquefied natural gas or biofuels) and technical improvements in aircraft engines (increasing their traction efficiency, implying a reduction in fuel consumption). However, this progress may be offset in the future by an increase in air transport activity.
To assess the air quality at the airport, as early as 2007, a "Guidance material on aviation emission charges related to local air quality" was developed, which implied the introduction of duties levied by the state, specifically designed and applied to prevent or reduce the environmental impact on local air quality caused by the operation of civil aircraft. The methodology for assessing the emissions of aircraft engines was set out in the Document 9889 "Guide to air quality in airports" [6], which was developed later. It formulated methods for estimating the emissions of aircraft engines at the airport, based on the consideration of three parameters. The first parameter is the time in minutes that the aircraft actually spends on setting one of the take-off and landing cycle modes: when the engine is running at low gas, during landing, during climb and take-off. The second parameter is the emission index EI (mass of the substance released during the combustion of a unit of mass of fuel) and the third is the fuel consumption. In [3] it is stipulated that for the purpose of certification of aircraft engines, the following types of emissions are normalized: smoke, unburned hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx).
The ICAO Engine Emission Data Bank (EEDB - ICAO Engine Emission Bank) contains information on the EI values for certified engines (in grams of pollutant per kilogram of fuel for NOx, CO and HC), as well as on the consumption of special fuels (in kilograms per second) for different operating modes of different types of engines. In addition, the number of smokiness - is indicated here, a dimensionless parameter calculated on a 10-point scale and characterizing the smoke emission as the" opacity " of the exhaust jet. The emission indicators for the PW4074D engine, which is equipped with, for example, A330 airbuses, are presented in Figure 2.
Figure 7. Emission indicators for the PW4074D engine from the ICAO emission data bank [7]

Operating mode

Engine power

Time

Fuel consumption

Fuel emission index

Smoke quantity

%

min

kg / s

HC

CO

Nox

Takeoff

100

0,7

3,042

0,02

0,3

42,46

4,22

Climb

85

2,2

2,471

0,02

0,35

32,71

2,36

Decrease

30

4

0,869

0,04

0,96

11,35

0,65

Small gas

7

26

0,305

3,12

26,34

3,8

0,33

Fuel (kg) and emissions (g) of TLC

1138

1502

12885

20269

-




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