In these days, the emission of nitrogen oxides and nitrogen dioxide into the air has become one of the most concerned issues. The aim of this study is therefore to determine the effect of industrial activities and vehicles on the concentration level of nitrogen oxides and nitrogen dioxide in a selected area, as well as the influence of temperature and relative humidity on the trend of pollutant concentration. Aeroqual AQM 60 station was used to monitor and record required data such as concentration of nitrogen oxides and nitrogen dioxide, ambient temperature and relative humidity.
The influence of temperature and relative humidity on the concentration of both pollutants was very significant, and this shows that weather conditions play an important role in the fluctuation of pollutants. Therefore, this study is very important to investigate the correlation and influence of meteorological parameters, operational activities and traffic volume to the concentration of nitrogen oxides and nitrogen dioxide.
INTRODUCTION
Problem Statement
One of the most dangerous air pollutants is nitrogen dioxide (NO2), which is generated by highly reactive gases known as nitrogen oxides or nitrogen oxides (NOx). The concentration of nitrogen dioxide will vary from place to place as the meteorological elements change over time. Breathing air with a high concentration of nitrogen dioxide can contribute to respiratory problems, such as lowering immunity against lung infections, wheezing, coughing, colds, flu and bronchitis.
The tendency to form acid rain will be significant in areas with high concentrations of nitrogen oxides and nitrogen dioxide. This research will thus investigate the influence of meteorological parameters, industrial activities and traffic volume on the concentration of nitrogen oxides and nitrogen dioxide in the Tronoh area.
Objectives
Scope of Study
LITERATURE REVIEW
Effects of Meteorological Conditions
Critical Review
METHODOLOGY
- Study Area
- Data Collection
- Data Analysis
- Gantt Chart
To ensure that the goal is achieved, several phases have been built, starting with the collection of information about the Tronoh area, followed by air pollution monitoring using the Aeroqual 60 Station, and finally the analysis of the concentration of nitrogen oxides and nitrogen dioxide in relation to traffic volume and industrial activities and meteorological parameters. The air pollution monitoring was carried out at three different locations in the Tronoh area and focuses on emissions from industries and vehicles. All collected data were analyzed using time series model analysis so that the trend of nitrogen oxides and nitrogen dioxide with respect to meteorological parameters and traffic volume can be observed at uniform intervals.
Monitoring of air pollution was carried out at three different points in the city of Tronoh, where the occurrence of air pollution is reported. The air pollution monitoring location was chosen to cover the entire area affected by the pollutants. An Aeroqual AQM 60 station was set up and installed at a selected point location for 12 hours to record the concentration of nitrogen oxides and nitrogen dioxide as well as ambient temperature and relative humidity.
In this study, all data collection and sampling was performed using an Aeroqual AQM 60 station. The station was set up and installed at three different locations within the study area to record concentrations of nitrogen oxides, nitrogen dioxide, temperature and relative humidity. Air pollution was sampled on 1 weekday and 1 weekend day for each location.
The number of vehicles was recorded manually at one monitoring site to correlate the effect of the traffic with the concentration of nitrogen oxides and nitrogen dioxide. In this way, the relationship between the traffic volume and meteorological parameters in relation to the concentration of nitrogen oxides and nitrogen dioxide can be analyzed more accurately and precisely. As previously mentioned, this study will focus on two air pollutants, which are nitrogen oxides and nitrogen dioxide.
RESULT AND DISCUSSION
Monitoring Point 1
The air monitoring station was placed near the main road to detect the occurrence of nitrogen dioxide and nitrogen oxides. Ambient temperature and relative humidity were also recorded by the Aeroqual AQM 60 Station and presented using time series analysis to see the effect of both meteorological parameters on the concentration of nitrogen dioxide and nitrogen oxides. The concentration of nitrogen dioxide and nitrogen oxides is presented on a peak hour basis, because these hours show the highest traffic volume and emit the highest amount of pollutants.
These situations, where the differences in traffic flow during weekdays and weekends are significant, create a significant difference in the amount of nitrogen dioxide and nitrogen oxides released into the ambient air. The concentration of nitrogen oxides during the weekday is much higher compared to the concentration of nitrogen oxides during the weekend due to heavy traffic volume and movement of people during the weekday. There is a small amount of nitrogen dioxide over the weekend due to rain, which prevents it from converting to ground-level ozone and nitric oxide, as rain prevents the direct sunlight reaction.
In short, it can be said that the concentration of nitrogen dioxide and nitrogen oxides depends on the volume of traffic, because when the volume of traffic increases, the concentration of pollutants increases as much as the amount of pollutants emitted into the ambient air. Based on graph 4.2.2.2, the concentration of nitrogen oxides somewhat follows the trend of relative humidity starting from 08:30 AM to 18:00 PM and decreases when the relative humidity decreases. However, there are no occurrences of nitrogen dioxide throughout the period as it had been converted to ground-level ozone and nitrous oxide due to reaction with direct sunlight.
From both graphs it can be said that the concentration of nitrogen oxides is fluctuating throughout the period and slightly follows the relative humidity trend from 11:30 to 18:00. The appearance of nitrogen dioxide during the weekend is due to less direct response from the sun during this period. This indicates that the weekend's weather is wet and creates a less direct response to sunlight, which prevents the conversion of nitrogen dioxide to ozone and nitrous oxide.
Monitoring Point 2
Based on the two graphs, we can say that the manufacturing industry did not contribute to the emissions of nitrogen oxides and nitrogen dioxide during the period of operation of the industry, because the concentration of both pollutants is very low and may be the result of emissions from passing vehicles. near the air control station. The highest concentration of nitrogen dioxide was 0.0065 ppm at 06:00 in the morning, when it began to fluctuate and steadily decrease until it reached its lowest point at 15:00 at 0.001 ppm. The concentration of nitrogen dioxide did not show any correlation with the operating hours of the industry, with the concentration presumably reaching its highest value during the operating hours.
The ambient relative humidity shows an inverse correlation with the temperature as shown in graph 4.3.1.2, as the ratio of water vapor in the air starts to decrease as the temperature increases. From graph 4.3.1.2, when the relative humidity decreases, the concentration of nitrogen oxides decreases and vice versa. This indicates that the variation in nitrogen oxide concentration was caused by temperature and relative humidity.
However, there was very little occurrence of nitrogen dioxide because only a small portion of nitrogen oxide was converted into nitrogen dioxide when it reacts with oxygen. Some of the nitrogen dioxide can be converted to ground-level ozone and recycled to become nitrogen oxides when it reacts with direct sunlight. The concentration of nitrogen oxides shows a slight fluctuation in the morning period due to the residential activities near the sky.
From both graphs, it can be seen that the trend of ambient temperature and relative humidity seems to have the same trend during the weekdays, except for sudden changes at 15:30 to 16:30 due to rainfall. When it rains, the ambient temperature will decrease as the amount of water vapor in the air increases, and as a result, the relative humidity will also increase. The concentration trend of nitrogen oxides tends to follow the trend of relative humidity due to the dependence of water vapor to carry the pollutant parcel with it.
Monitoring Point 3
Based on graph 4.4.1.1, the concentration of nitrogen oxides is low in the morning with an average concentration of 0.003 ppm. In addition, the drastic increase in the concentration of nitrogen oxides occurs due to the sudden increase in the amount of trucks and lorries entering the delivery industry. The relative humidity trend is inversely correlated with the ambient temperature, as shown in graph 4.4.1.2.
Based on Graph 4.4.1.3 and 4.4.1.4, the concentration of nitrogen oxides during weekend is much lower compared to the concentration during weekday. There is no correlation between the emissions from the industry and the concentration of nitrogen oxides because the industry does not operate during the weekend. The concentration of nitrogen dioxide is negligible because it has either been converted to ground-level ozone or recycled to nitrogen oxides when it reacts with direct sunlight.
The relative humidity trend is inversely correlated with the ambient temperature as shown in graph 4.4.1.4. The concentration trend of nitrogen oxides somewhat follows the trend of relative humidity due to the dependence of water vapor to carry the pollutant parcel with it. With the completion of this study, the trends of nitrogen oxides (NOx) and nitrogen dioxide (NO2) can be determined in the Tronoh area, where the maximum concentration of nitrogen oxides is 0.0333 ppm while for nitrogen dioxide it is 0.0035 ppm.
Next, the relationship between the concentration of nitrogen oxides and nitrogen dioxide with the industrial activities and traffic volume can be clearly seen and analyzed. From the analysis, the biggest contributor to the concentration of nitrogen oxides in Tronoh is from vehicle emissions, including cars, motorbikes, buses, trucks and lorries. For industrial activities, all selected manufacturing industries in Tronoh do not contribute to the direct emission of nitrogen oxides and nitrogen dioxide.
The occurrence of nitrogen dioxide is very small and below 0.16 ppm, as stated by the Malaysian Ambient Air Quality Standard, because it was converted to ground-level ozone and recycled back to nitrogen oxides when it reacts with sunlight. direct sun. Both meteorological parameters, which are temperature and relative humidity, affect the concentration of nitrogen oxides.
