AIR POLLUTION Chapter 3. Ambient Air Quality ... -

AIR POLLUTION Chapter 3. Ambient Air Quality ... -

3g/mm12108642Maximum permissibleconcentration in EUMaximum permissibleconcentration in GeorgiaCarbon monoxide is a product ofincomplete combustion. Its mainsource is exhaustions of motorvehicles (generated in the process ofincomplete combustion due toinsufficient temperature, or due tomalfunction of air supply system ofthe internal combustion engine). It isalso emitted from energy productionplants in particular those using, oiland coal combustion, and from themetallurgical industry. It suppressestransportation of oxygen by blood02005 2006 2007 2008 2009yearFigure 3.3 Mean annual concentration of carbon monoxide in Tbilisi

3/mgm0. permissible concentration inGeorgiaMaximum permissible concentration inEUNitrogen dioxide and monoxideare the products of fuelcombustion at a very hightemperature in abundance ofoxygen. The main sources aremotor vehicle exhaust, andemissions from power stationsand the burning of solid wasteAt high concentrations inambient air nitrogen dioxide canirritate the lower airways of therespiratory tract, especially thelungs.02005 2006 2007 2008 2009yearFigure 3.4 Annual concentration of nitrogen dioxide in towns of GeorgiaManganese dioxide is a highlytoxic substance, the main sourceof which is metallurgical industry.Manganese dioxide has an impacton the central nervous system.0.010.0080.0063g/mm0.0040.002Maximum permissibleconcentration in Georgia02005 2006 2007 2008 2009yearFigure 3.5 Manganese dioxide mean annual concentrations in Zestaphoni

present the Ferro-alloys plant is a significant source of manganese dust emissions leading toexceedence of ambient air quality standards in this as evidenced by the latest data from theEnvironmental Monitoring Observation Network.Energy sectorThe Energy sector (high capacity thermoelectric power stations) in Georgia comprises three bigplants working mainly on natural gas. These are: JSC ”Energy Invest”, Ltd, ”Mtkvari Energetika”,and JSC ”Tbilsresi”.Since the municipal power companies were dissolved in the 1990’s, the energy supply systems inbig towns and other settlements has virtually disappeared. People now use individual heatingsystems working mostly on gas and wood.Volatile organic compounds (VOC’s), carbon monoxide (CO) and solid particulates (dust) are themain pollutants from the energy sector. Changes in the emissions from this sector are by andlarge caused by changes in the fuel consumption patterns (coal, kerosene, mazut, natural andliquid gas, and etc.), where coal and mazut are considered dirtier fuels and natural and liquid gasconsidered as cleaner fuels.Motor transportThe transport sector is the main source of air pollution in Georgia. The main emissions from thesector include carbon monoxide (CO), carbon dioxide (CO 2 ), nitrogen oxides (NO x ), sulphurdioxide (SO 2 ), particulates and polyaromatic hydrocarbons (PAH’s)As such air quality is impacted more in areas where there are heavy traffic levels. The most acutesituation is observed in Tbilisi, where almost one third of the total transport fleet is based.The impact of transport is described in more detail in chapter 19. Some main issues are detailedbellow. Emissions from the transport sector are governed by a number of issues for example;• the average age of the national fleet, and the emissions standards set for vehicles• how vehicles are maintained, and checked to ensure they comply with emission standards,• fuel quality standards (e.g. sulphur content) and the overall composition of the fleet e.g.petrol vs diesel, gas etc• traffic management, i.e. whether traffic is free flowing or whether there is significantcongestion, and;• General use patterns, e.g. how many people use private transport versus public transport,etc.In Georgia the public transport system is not sufficiently developed and as a consequence asignificant proportion of the population uses private vehicles as the preferred mode of transport.As a result the number of private vehicles has grown rapidly over the past decade and has almostdoubled in the last five year period (see figure 3.8). Most of the cars purchased are second-handcars imported from aboard, and the average age of the car feet in Georgia is 10-15 years. Dieselengine cars are very popular (see the sharp increase in diesel fuel consumption on figure 3.7).Roadworthiness testing of vehicles is no longer in operation in Georgia and as result many cars onroads are in a bad technical condition. Periodic testing of exhaust gases has also beensuspended. Some low quality fuel available on market quickly damage the catalytic converters invehicle exhaust. Car owners tend to have the damaged catalytic converters removed and not

Figure 3.15 Annual emission of gases with potential to generate fine suspended particulates bysector.3. Main challengesResults obtained from the existing air quality monitoring programme show that the concentrationsof main pollutants in all four towns in which monitoring takes place are exceed permissiblestandards. The small number of monitoring locations in the existing network does not allow acomprehensive assessment of air quality even within the limits of these towns. To have the realpicture of air quality in the country the installation of at least one measuring point in urban areasfor each 100 thousands citizens is desirable (also taking into account the level of pollution). Inaddition the existing suite of pollutants, the monitoring programme should be expanded to includeparameters such as small particulate matter (PM 10 ) .Three new monitoring stations were installed in late 2009, two in Tbilisi and one in Rustavi.However additional coverage is required to provide more comprehensive monitoring in accordancewith international requirements and standards. Improvements in the monitoring network willprovide more detailed and reliable data which will allow the decision makers to better plan andimplement measures for air quality improvement.Despite the lack of monitoring data it is clear that the transport sector is the primary source of airpollution in Georgia. Emission of polluting substances from this sector is increasing year on yearand this trend is expected to continue. National standards for fuel quality and motor vehiclesemissions are lower than for those in EU legislation. Unfortunately the economic situation withinGeorgia does not allow for the immediate adoption of standards comparable to those within theEuropean Union. However it is essential that these standards be continuous improved over theshortest time frame possible in order to effect a reduction in emissions from this sector. This taskwill be made more difficult by the rapid increase in private car ownership underway in Georgia.Consideration should be given to reducing the age limit of second hand cars imported in toGeorgia. Roadworthiness testing and emissions testing for all vehicles should be resumed as amatter of urgency. All cars being imported into the country should be tested under this vehicletesting regime and must comply with these standards prior to registration.Improved traffic management systems aimed at reducing congestion within cities should also beinvestigated. The provision of an improved public transport network may also lead to a reduction ofvehicle numbers in the cities, and initiatives such as priority buss corridors and restrictions ofprivate vehicles in some city areas could be examined.Georgia could also look to the future and consider the use of electric powered vehicles. Thistechnology is now coming of age, and giving the abundance of electricity which can be generated

from natural resources within the country, Georgia may be well placed to reap the benefits of thisnew technology both as a means of public and private transport.The concentration of manganese dioxide in Zestaphoni significantly exceeds permissible levels. Aremediation programme is underway which will include the instillation of dust abatementequipment which will reduce the emissions from the plant and bring these levels back intocompliance.Bibliography• WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulphur dioxide. WHO/SDE/PHE/OEH/06.02.• EMEP/CORINAIR Emission Inventory Guidebook – 2007.• The IPCC Guidelines on National Greenhouse Gas Inventories.

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