EFFECT OF NEARLY ONE HUNDRED PERCENT OF MUNICIPAL SOLID WASTE RECYCLING IN NAJAFABAD CITY ON IMPROVING OF ITS AIR QUALITY

Introduction: Now, 100% of solid waste in Najafabad is recycled. The main aim of this study is to evaluate the effect of 100% solid waste recycling on emissions of CO2, CH4 and more than 40 non-methane organic compounds from landfill to the atmosphere. Materials and methods: To achieve this aim, it is assumed that if 100% solid waste recycling were not carried out in Najafabad, and if this city had a landfill with enough capacity to accept its solid waste for 20 years, a significant amount of the mentioned gases would have been emitted into the atmosphere. With this assumption, all necessary information about the amount of solid waste production in Najafabad was collected and the amount of gases released into the atmosphere was calculated by LandGEM software. Results: The results show that for landfilling of Najafabad solid waste over 20 years, a landfill with capacity of 2.3 million m3 is needed. Total generated CO2 and CH4 from this imaginary landfill during 20 years of fictional landfill operation are 107206 and 39074 tons, respectively. In addition, considerable amounts of CH4 and CO2 emission would continue for an estimated 120 years after landfill closure year. Calculations show that in 2015 alone, 93.79 tons of hazardous non-methane organic compounds could have been emitted into the atmosphere, most of them toxic and carcinogenic. Conclusions: Today's 100% solid waste recycling in Najafabad has completely avoided these emissions. Consequently, it is recommended that nearly 100% solid waste recycling must become the final goal in all Iranian recycling organizations, to decrease landfill costs and to realize a healthier environment.