Determination of environmental impact and energy recovery from municipal solid wastes in the Northwest of Iran

Unsuitable management of municipal solid waste (MSW) is one of the main factors in environmental degradation, particularly in developing countries. This study aimed to analyze the quantitative and qualitative properties of MSW for energy recovery in the city of Mahabad, located in the West Azerbaijan Province, Iran.

Sampling from MSW was taken during the four seasons in 2014. Quality and quantity analyses included chemical composition, moisture percentage, dry weight, ash percentage, and heat value, which were performed in the lab as per the American Society for Testing and Materials Method D 5231-92. The experience modeling was used to extract chemical composition and heat value.

The results showed that MSW was composed of 75% food waste, 12% ash, and 61% moisture. In the MSW organic fraction (C28.7H43.6O15.3N1S0,065), carbon/nitrogen and heat values were found at 28.7 and 2.1 × 104 Kj Kg-1, respectively. Also, in the MSW biodegradable organic fraction (C23.7H37.7O14.69N1S0.069), heat value and produced methane were calculated to be 10077 Kj Kg-1 and 207 liters (148 g), respectively. Any carbon dioxide added to the atmosphere will hang around for a long time, between 200 and 200 ton day-1, which contributes to trapping heat and warming the atmosphere.

This study shows energy recovery from MSW is a good option, due to the high heat value. However, it is not an eco-friendly method as it will produce more greenhouse and poison gases and needs control systems.