Though it may be possible to model any complex process mathematically, cold model experimental studies of the process/operation are considered to be essential and important. These studies are less difficult to perform than the actual processes, and they are useful in better understanding the complex processes and operations, foreseeing the problems that may crop up during the actual operation, and optimizing and designing the system. Experimental studies are carried out on a transparent semicircular cold model of a recirculating fluidized bed (RCFB) incinerator intended fur burning low-heat-content liquid waste. Information from the cold model experiments are used to design the incinerator by choosing suitable operational and design parameters.