Air quality in Karachi, Pakistan appears to be deteriorating in the world due to rapid increase in population, economic growth and subsequent increase in urbanization and energy demand. This study Re-is about the cumulative effects of anthropogenic activities on air chemistry of the study area atmosphere with ground base concentration measurements of gaseous air pollutants (SO2, NO2, CO, CO2 and O3), particulates (PM10 and TSP), Methane, Lead and Noise with temperature and seasonal influences on Karachi city. The primary goal of this study was to define spatial and temporal distribution of air pollutants with ArcGIS, seasonal behavior of airborne contaminants, convert the five major pollutants termed as criteria pollutants into Air Quality Index (AQI) and their temperature association for future prospects. The maximum average values of four seasons concentrations of air pollutants were found SO2=64.5 ug/m3 (GR), NO2=55.5 ug/m3 (FB), CO= 8.00 mg/m3 (CC), CO2=645 ug/m3 (NZ), O3=56.7 ug/m3 (ST), PM10=225 μg/m3 (CC), TSP=402 ug/m3 (CC), Methane=1.65 m/gm3 (CC), Lead=5.1 ug/m3 (ST), and Noise=85 dB (GR). The minimum four seasons average concentration values with monitoring location as {SO2=48.2 ug/m3 (FB), NO2=44.6 ug/m3 (NZ), CO=4.1 mg/m3 (BC), CO2=601 ug/m3 (JH), O3=42.4 ug/m3 (GR), PM10=150 ug/m3 (BC), TSP=226 ug/m3 (JH), Methane=0.68 mg/m3 (BC), Lead=32 ug/m3 (GZ), and Noise=81 dB (BC). The spatial-temporal analysis of air quality revealed that the pollutants in the summer are higher in industrial and high-density traffic junctions. In this study, temperature and air quality are significantly associated, while rainfall and relatively high humidity days are negatively correlated. High temperature months have highest air pollution values, whereas the washout impact of precipitation and relative humidity have the lowest levels. The analysis of air quality index parameters demonstrated a high coherence among NO2, CO and O3 with variation in

Pakistan has experienced a protracted electricity shortage for the past few years. However, despite Pakistan’s abundant coal deposits, modern coal combustion technology is still required to reduce emissions. Pakistan is struggling to utilize its energy resources and currently experiencing an electrical shortage of more than 8000 MW. The research study models the combustion performance in a fluidized bed riser using ANSYS FLUENT software to understand the combustion behavior of low-rank Thar coal. A simple circulating fluidized bed (CFB) combustion riser was modeled for computational fluid dynamics (CFD) to study the hydrodynamics of gas-solid flow in a circulating fluidized bed riser to reduce emissions and operating costs. Three different types of risers/combustors geometries were used center flow, counter flow, and parallel flow. The CFD model for the solids segment with a k-e turbulence model and the viscosity of static particles in the gas segment both showed excellent mixing performance. According to the FLUENT data, the riser/combustor maximum temperature is around 1400 K or 1130 o C at the primary burning sector in the bed center. According to velocity contours, the greatest velocity in the center-oriented riser/combustor peaks at 3.3 m/s. The CO and CO2 both mass fraction counters show maximum concentration in the center geometry, whereas lower CO concentration is found in parallel geometry. The lowest level of NOx is established in the parallel geometry at around 15 ppm, whereas the counter contours establish the maximum level of NOx at about 31 ppm. Circulating Fluidized Bed Combustor is found to be the most advantageous and effective technology for producing power from Thar lignite coal and reducing emissions.