1. The impact of the transportation sector on the air quality in the agriculture-oriented District of Devoll, Albania
Dr. Edlira F. MULLA
Department of Chemistry
Faculty of Mathematical Engineering & Physical Engineering
Polytechnic University of Tirana – ALBANIA
Keywords: Air pollution, Devoll district, PM emissions, Vehicle fleet.
INTRODUCTION
Devolli District is agriculture-oriented therefore the air is perceived by its inhabitants to be cleaner compared to other larger cities in Albania. The number of vehicles with DV license plate has known a tremendous increase in the last two decades, with the private cars dominating the vehicle fleet. The vehicle pressure is noticeably felt on the national highway especially when emigrants return to Albania 2-3 times a year, entering the District by driving via Kapshtica border point.
Bilisht is a small city, yet driving a car within the city and from / to the villages around is becoming a new way of living, thus posing problems such as: people’s safety in the streets, very limited parking places and a rapid increase in the number of fuel stations. Not much is known about the real air quality because there has never been installed an air monitoring station there. About 60 % of vehicles are inspected annually whereas the 40 % of them circulates in the streets unispected. The majority of cars runs on Diesel.
The aim of this research was to evaluate the vehicle fleet composition for Devolli District, to define the trend of the progress of vehicle numbers in the last decade and to distinguish the most significant contributor to the air pollutant emissions. Smoke measurements of the vehicles’ emissions were carried out and results were compared with the opacity limits.
RESULTS
The description of the Target group of cars studied, research findings and testing results are summarized in Figures 4- below:
Table 2: Description of the target group of 105 Diesel cars studied and the summary of results of measurements of the
Coefficient of Opacity K (m-1) for each category.
Cars’ registration in Devolli District:
Total number of cars studied:
Average age of cars at the moment of purchase
Average age of cars at the moment of testing
Coefficient of opacity
Average value of
K (m-1)
Number of cars exceeding the norm of K / no. of cars of that category, based on production year.
Before 1988
K> 4.0
Between
K > 3.5
After 1998
K >2.5
Municipality 33
14.2
19.4
3.3
6 / 16
2 / 14
3 / 3
Communes 72
16.02
21.25
3.48
18 / 42
8 / 27
Private cars 93
15.8
20.93
3.642
22 / 53
10 / 34
6 / 6
Taxi cars 12
12.67
18.75
1.882
2 / 5
0 / 7
0 /0
METHODOLOGY
The PM concentration in the exhaust gases was measured from the light weakening after it passes through the mixture of exhaust gases in the tailpipe, by using the Lambert – Beer equation [6, 7]. Coefficient of opacity K (m-1) summons the concentration of PM inside the exhaust gases from the diesel combustion in the engine as well as the dimensions and the nature of these particulates.
I / Io = e – K L = e – a · c · L , where K = a·c
a is the concentration of the particulate matter,
c indicates the dimensions and the nature of particulates,
Io is the light intensity when there is no smoke [PM] at all in the exhaust gases,
I is the light intensity when there is smoke [PM] in the exhaust gases,
L is the length of the tube where the measurement of the light intensity is taking place (in meters).
The absorption Coefficient, K (m-1), and not the real PM concentration in the exhaust gases was measured with this equipment. The higher the K values, the higher the PM concentration in the exhaust gases of cars. The allowed norms of opacity are given in Table 1 below:
DISCUSSIONS
The majority of the cars in Devolli District run on Diesel. Along the highway Korça – Kapshtica there are various and many fuel stations. It can be said that the fuel quality available to the Municipality cars and to the Commune cars is basically the same. Driver’s preferences are the ones that determine exactly which type of fuel they choose to purchase on daily basis.
As it can be seen from Table 2 and Figures 4-9 above, the Diesel cars registered in Communes of Devolli District are a little older and pollute slightly more than the Diesel cars registered in the Municipality of Bilisht, as it can be reasoned by the average value of the Coefficient of opacity K (m-1).
A very sharp contrast is noticed between the private passenger cars and the taxi cars in Devolli District:
Private passenger cars are much older and pollute much more than the taxi cars, as it can be reasoned by the average value of the Coefficient of opacity K (m-1). One possible reason is that taxi cars in general run on better quality Diesel and also they are much better taken care of compared to private cars. One more reason is that Taxi cars undergo the obligatory check up test twice a year, compared to the private cars which undergo this test only once a year.
Even relatively new cars, which run on bad quality Diesel and which do not undergo regular check up and service, can pollute just as much and even more than the old cars.
Gasoline cars are a very small component of the whole traffic fleet. The ones that were analyzed under this research initiative showed that the key in having low CO and HC emissions is maintaining the catalytic converter in optimal working conditions by using unleaded gasoline [Euro 5] on daily basis.
Table 1: The allowed norms for the pollutants (opacity) that are released with the exhaust gases from the Diesel vehicles No
Year of Production
Type of Fuel
Diesel Engine
Absorption Coefficient
K (m-1) 1.
Before 1988
Diesel
Natural induction
With turbocompression
4.0
4.5 2.
3.5 3.
After 1998
2.5
RECOMMENDATIONS
Based on the main findings of this research, it is recommended that these steps be undertaken:
Installing a traffic numbering system on city’s entrance points in order to know the exact number of cars that run on the highway which passes in the middle of Bilisht City and make traffic management plans in the future.
Enabling pilot measurements of air pollutants, such as PM (particulate matter), on the roundabout and the entrance point in the city, will give a clearer picture of the situation.
Awareness raising projects with inhabitants and emigrants regarding environmentally friendly behavior [driving less inside the city, which is small and easy to walk around] will result on a healthier lifestyle for them.
REFERENCES
1. General Directory of Services to the Road Transport. Tirana, Albania. March 2011.
2. Fletore Zyrtare e Republikës së Shqipërisë. Nr Pg
3. Fifield F. W. And Kealey D (1983) – Principles and practice of Analytical Chemistry. 2nd edition. International Textbook Company Limited. London Pgs. 278, 310.
4. Kihara Nobutaka (2001) - PM measurement. Opacimeter MEXA-130S. Readout. (2001) Vol. No 23; Pgs