STUDY ON CHARACTERISTICS OF MUNICIPAL SOLID WASTE IN VIETNAM FOR ENERGY APPLICATIONS

Abstract

Waste incineration technology for energy recovery is considered a potential method in waste treatment. However, the source of civil waste in Vietnam has a high organic content (60 - 70%) and low calorific value (4500 - 6000 kJ/kg), leading to low efficiency of heat utilization when burning waste directly. Therefore, the input waste fuel needs to be separated from moisture and organic and inorganic components before being supplied to the combustor. This paper studies the separation of moisture and organic and inorganic components of waste. The effects of inlet moisture and the composition of organic and inorganic waste fuel, before and after separation, on calorific value and heat utilization efficiency were evaluated. The results showed that when the organic components in the waste were reduced from 65.8% to 43.6%, the low calorific value of the waste increased by 1.44 times from 5432 kJ/kg to 7839 kJ/kg, compared to the original garbage sample. The low calorific value of the waste can reach nearly 10,000 kJ/kg when approximately 80% of the organic components are removed from the original waste sample. Meanwhile, the moisture content of the waste decreased by 11.2% and 43.3%, respectively, compared to the original sample, and the heat capacity increased by 1.93% and 5%, respectively. The temperature of the combustion chamber also increased to 60 - 70°C when the moisture content of the waste decreased by approximately 10%. Furthermore, the results showed that reducing the excess air coefficient from 1.8 to 1.5 at the same fuel moisture level of 30% increased the temperature of the combustion chamber to 120°C. The results obtained in this study will serve as a reference for the design and operation of combustors that use waste fuel for heat recovery and energy production in Vietnam.