An Investigation on Co-Combustion Behaviors of Hydrothermally Treated Municipal Solid Waste With Coal Using a Drop Tube Reactor

This work aims at demonstrating the feasibility of replacing Indonesian coal (INC) with hydrothermally treated municipal solid waste (MSWH) in co-combustion with high ash Indian coal (IC). Combustion behaviors of MSWH, INC and their blends with IC were tested in a laboratory-scale drop tube reactor (DTR). The combustion efficiency and emissions such as CO, NO for a series of tests performed under a range of temperatures and air conditions were evaluated and the main results derived from this study can be concluded as the followings: the combustion efficiency of IC is increased by blending both MSWH and INC and CO emission is reduced in the meanwhile with the temperature rising. With regards to NO emission, the blending of MSWH leads to the increase of NO emission whereas the blending of INC results in either the increase or decrease of NO emission compared with IC only combustion depending on the temperature. The combustion behaviors of IC-MSWH blend are comparable to that of the IC-INC blend indicating it is possible for MSWH to become a good substitute for INC in the co-combustion with IC. The CO emission falls while the NO emission rises with the increase of the excess air in the case of IC-MSWH blend at 900 °C and the highest combustion efficiency is obtained at the excess air of 1.9. The existence of moisture in the co-combustion system of IC-MSWH blend can slightly improve the combustion efficiency, reduce CO emission and increase NO emission. The results of this work are expected to be a good instruction for the application of MSWH for co-combustion with coal.