Towards Biomass Gasification Enhanced by Structured Iron-Based Catalysts

The main drawback for the development of biomass gasification technology is tar conversion. Among the various methods for tar abatement, the use of catalysts has been proposed in the literature. Most of the works reported in the literature on catalytic systems for biomass tar conversion refers to catalysts in the form of powder; however, deactivation occurs by fast clogging with particulates deriving from biomass gasification. The integration of catalytic filter element for particle and tar removal directly integrated into the freeboard of the reactor is a new concept recently proposed and patented. In this context, this paper evaluates the possibility to integrate a structured iron-based catalytic monolith in the freeboard of a fluidized bed gasifier to enhance biomass gasification. The effectiveness of using a monolith for gas conditioning has been preliminarily verified. The limited effect on the gas production and composition seems to be related to the limited range of operating conditions explored in this work rather than to the low activity of the iron-based catalyst. Further studies to optimize the performance and to assess the possible deactivation of the catalyst due to coke deposition must be carried out.

The Denitration and Dedusting Behavior of Catalytic Filter and Its Industrial Application in Glass Kilns

The development of efficient materials and processes is a long-term goal for the integrated flue gas purification in industry. In this study, a large-size V-based catalytic filter (L3000 mm × Φ150 mm) was prepared by loading the catalyst emulsion into a blank filter, which demonstrated excellent performance for simultaneously removing NOx, SOx and dust. The laboratory investigation found that the small catalytic particles, high catalyst loading and low face velocity could improve the DeNOx efficiency, and above 80% NO conversion could be achieved in the temperature range of 250–400 °C on the condition of <300 nm catalytic particle size, >7.41 wt % catalyst loading and <1.00 Nm/min face velocity. The negative effect of SO2/H2O was only observed below 300 °C, and the dust had little negative effects on DeNOx efficiency except for the increase of pressure drop. Moreover, a 90-day industrial test of 2380 catalytic filters over 100,000 Nm3/h of flue gas (0.50 Nm/min) from a glass kiln demonstrated that the removal efficiency of both NOx and SOx could be maintained above 95% with great stability at 320–350 °C, and 99% dust could be removed with a pressure drop of less than 1.40 KPa. The results reported herein indicate the promising application prospect of large-size V-based catalytic filters for integrated flue gas purification in industry.