Modeling and simulation of an improved ammonia-based desulfurization process for Claus tail gas treatment

An improved ammonia-based desulfurization technology was proposed, in which the produced excess NH4HSO3 was concentrated by using the heat from the Claus tail gas and then SO2 was recovered by decomposing the concentrated NH4HSO3 in the Claus furnace. Furthermore, the process was modeled and simulated using the commercial software Aspen Plus. The characteristics of the ammonia-based desulfurization model were validated and compared with experimental results. Moreover, the water balance in the system was maintained, therefore, no extra water was required. Under the water balance condition, the SO2 removal performance in the system was predicted with various operating conditions. The model exhibited a reliable prediction of the desulfurization performance of the innovative process, which will be favorable for actual industrial application.