SATURATION TIME ANALYSIS OF NITROGEN DIOXIDE DIFFUSION PROCESS ON PASSIVE SAMPLERS FOR AMBIENT AIR MONITORING

• Main Author: SERLINA (NIM: 25315016), YEGA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/31722
• Institution: Institut Teknologi Bandung

Passive sampler operates with the principle of diffusion of gas from the atmosphere through the sampler dimension until it reaches the absorbent media. The study was conducted to analyze changes in NO2 concentrations measured on passive badge samplers and passive tube samplers for a sampling duration of six to fourteen days. The difference in concentration in each variation of sampling duration is used to determine the passive sampler diffusivity so that the actual diffusivity coefficient (Dactual) is obtained. The measurement location is adjacent to the DKI-1 air quality monitoring station (AQMS) in the Bundaran HI area, DKI Jakarta. The measured NO2 concentration in the passive sampler was validated with NO2 concentration data from measurements of the DKI-1 AQMS. Validation using Chi Square analysis showed that the NO2 concentration measured on the passive sampler did not have a significant difference with NO2 concentration measured at the AQMS but from the comparison of concentration values, the measurement results using a passive sampler had a smaller concentration value compared with measurement results from AQMS. Linear regression analysis was used to model changes in NO2 concentration in the passive sampler to changes in sampling duration and meteorological factors (temperature, air humidity and wind speed). The temporal factor has an effect of 54.02% on the sampler badge and on the sampler tube is 79.22%. Meteorological factors have no significant effect and tend to have very little effect on measured concentrations The average Dtheoritical value is 0.158 cm2/second. Dactual passive sampler is calculated for each concentration difference (sampling duration interval) and compared with Dtheoritical obtained from the diffusion model equation which considers meteorological factors. The results of Chi Square analysis show that the diffusion equation Buzica et al. (2005) can predict diffusivity of sampler badges and tube samplers for NO2 measurements in Bundaran HI. Heal and Cape (1997) model shows that there is a measured change in concentration in the passive sampler which shows that there is an effect of the duration of exposure on the diffusion process on the passive sampler.